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Home My WebLink AboutPart 1.pdfDESIGN CRITERIA September 2015 Updated: October 2015 CITY OF MAPLE RIDGE DESIGN AND CONSTRUCTION DOCUMENTS PART 1 DESIGN CRITERIA MANUAL THIS PAGE INTENTIONALLY LEFT BLANK City of Maple Ridge Design Criteria Manual September 2015 Contents 1 TABLE OF CONTENTS Page SECTION G – GENERAL........................................................................................ .......................................1 G1 INTRODUCTION ............................................................................................................................1 G2 SURVEY INFORMATION................................................................................................................2 G3 DRAWING SUBMISSION.......................................... .....................................................................2 G3.1 Cover sheet................................................................................................................ ..............3 G3.2 Key Plan...................................................................................................................................3 G3.3 Storm Water Management and Lot grading Plan ..................................................................4 G3.4 Road and Water ......................................................................................... ..............................5 G3.5 Storm and Sanitary Sewers .....................................................................................................6 G3.6 Road Cross-Sections......... .......................................................................................................6 G3.7 Ornamental Street Lighting Plan.......................................................... ...................................6 G3.8 Street Tree and Boulevard Planting Plan ...............................................................................7 G3.9 Construction Details........... ......................................................................................................7 G3.10 Notes for Construction................................................................... ......................................7 G3.11 Seal and Signature...............................................................................................................7 G3.12 Other Requirements.............................................................................................................7 G3.13 First Submission............................................... ....................................................................8 G3.14 Submission Revisions....................................................................................................... ...8 G3.15 Final Submission..................................................................................................................9 G4 CONSTRUCTION COST ESTIMATE .......................... .....................................................................9 G5 RECORD DRAWING SUBMISSION ...............................................................................................9 G6 SEISMIC DESIGN STANDARDS................................................................................................. 11 SECTION R – ROAD ..................................................... ............................................................................. 13 R1 INTRODUCTION ...................................................................................................... ................... 13 R2 CLASSIFICATIONS ..................................................................................................................... 13 R3 GRADES........................... ......................................................................................................... 14 R4 CROSS-SLOPES .......................................................................... ............................................... 14 R5 HORIZONTAL AND VERTICAL CURVES ..................................................................................... 14 R6 CURB RETURNS ........................................................................................................................ 15 R7 CUL-DE-SACS.................................................... ........................................................................ 15 R8 TEMPORARY TURNAROUNDS................................................................................................... 16 R9 INTERSECTIONS....................................................................................................................... 16 R10 CROSS SECTION CONSIDERATIONS ....................... ................................................................. 16 R11 ROAD BASE, PAVEMENT DESIGN AND PATCHING .................................................................. 17 R12 SPECIAL DESIGNS..................................................................................................................... 18 R13 DRIVEWAYS ............................................ ................................................................................... 18 R13.1 Residential Access to Arterial and Collector roads ....................................................... .. 18 R13.2 Number of Driveways........................................................................................................ 18 R13.3 Driveway Location and Width .......................... ................................................................. 19 R13.4 Driveway Grades ............................................................................................................ ... 19 R13.5 Driveway Letdown and Curb Return ................................................................................ 19 R14 EMERGENCY ACCESSES .............................................. ............................................................ 19 R15 BOULEVARDS ........................................................................................................................ .... 20 R16 SIGNAGE................................................................................................................................... 20 R17 CURBS, SIDEWALKS AND WALKWAYS .................................................................................... 20 R17.1 Curbs and Gutters....................................................................................... ...................... 20 R17.2 Wheelchair Ramps............................................................................................................ 21 City of Maple Ridge Design Criteria Manual Contents 2 September 2015 R17.3 Sidewalks................................................................................................................... ....... 21 R17.4 Walkways ........................................................................................................................... 22 R17.5 Handrails .............................. ............................................................................................. 22 R18 BIKEWAYS AND EQUESTRIAN TRAILS.................................................................... .................. 22 R19 PAVEMENT MARKING AND STREET SIGNS ............................................................................. 22 SECTION D – DRAINAGE ..................................... ...................................................................................... 25 D1 INTRODUCTION ............................................................................................. ............................ 25 D2 STORMWATER MANAGEMENT PRINCIPLES............................................................................ 25 D2.1 Responsibility ................................ ........................................................................................ 25 D2.2 Tier A ............................................................................................... ...................................... 26 D2.3 Tier B..................................................................................................................................... 26 D2.4 Tier C ..................................................................................................................................... 26 D2.5 Stormwater Management Plan ........................................................................................... 27 D3 DESIGN FREQUENCIES.................................................................................. ........................... 28 D4 RUNOFF ANALYSIS.................................................................................................................... 28 D5 RATIONAL METHOD .................................................................................................................. 29 D5.1 Runoff Coefficients ....................................................... ........................................................ 29 D5.2 Soil Adjustment Factor.......................................................................................................... 29 D5.3 Catchment Area..................................................................................................................... 30 D5.4 Time of Concentration ............................ .............................................................................. 30 D5.5 Rainfall Intensity.............................................................................................. ...................... 31 D6 RUNOFF HYDROGRAPH METHOD ............................................................................................ 35 D6.1 Selection of Modeling Program ............................................................................................ 35 D6.2 Design Rainfall ................................................................................. ..................................... 35 D6.3 Watershed Data .................................................................................................................... 36 D6.4 Presentation of Modeling Results........................................................................................ 37 D7 STORMWATER STORAGE FACILITIES ......................................... .............................................. 37 D7.1 Release Rates ....................................................................................................................... 37 D7.2 Design Volume (Small Catchments) .................................................................................... 38 D7.3 Design Volume (Large Catchments) ............................... ..................................................... 42 D7.4 Outlet Control ........................................................................................................................ 42 D7.5 Emergency Overflow ............................................................................................................. 42 D7.6 Operation and Maintenance Requirements............... ......................................................... 43 D7.7 Safety Barrier and Signage................................................................................................... 43 D7.8 Detention (Dry) Storage ........................................................................................................ 43 D7.9 Retention (Wet) Storage ............................. .......................................................................... 44 D7.10 On-Site Detention Storage.......................................................................................... ...... 44 D8 STORM SEWERS AND APPURTENANCES ................................................................................ 45 D8.1 Sizing of Storm Sewers ........................................... .............................................................. 45 D8.2 Minimum/Maximum Velocity ............................................................................................... 46 D8.3 Minimum Depth of Cover...................................................................................................... 46 D8.4 Pipe Joints ............................................. ................................................................................ 46 D8.5 Curvilinear Sewers ........................................................................................... ..................... 47 D8.6 Sewer Location...................................................................................................................... 47 D8.7 Utility Separations ................................................................................................................. 47 D8.8 Manholes – Standard Requirements............................................ ....................................... 47 D8.9 Manholes – Hydraulic Losses .............................................................................................. 48 D8.10 Catch Basins...................................................................................................................... 52 D8.11 Lawn Basins .................................................... .................................................................. 52 D8.12 Temporary Clean-Outs ...................................................................................................... 52 City of Maple Ridge Design Criteria Manual Contents 3 September 2015 D8.13 Service Connections ........................................................................................................ . 53 D8.14 French Drains .................................................................................................................... 53 D8.15 Rock Pits....................................... .................................................................................... 54 D9 MAJOR FLOW ROUTING AND FLOOD CONTROL...................................................................... 54 D9.1 Major Flow Routing ............................................................................................................... 54 D9.2 Roadway Surface Drainage .......................... ........................................................................ 54 D9.3 Ditches............................................................................................................... ................... 57 D9.4 Watercourses ........................................................................................................................ 57 D9.5 Culverts and Bridges......................................................................................................... 57 D9.6 Inlet and Outlet Structures ................................................. .................................................. 58 D9.7 Site and Lot Grading ............................................................................................................. 58 D9.8 Minimum Building Elevations (MBE).................................................................................... 59 D9.9 Roof Drainage................................................... .................................................................... 60 D9.10 Swales................................................................................................................... ............ 60 D9.11 Siltation Controls............................................................................................................... 60 D9.12 Oil and Grit Separators ..................................................................................................... 60 D9.13 Oil/Water Separators................................................................... ..................................... 61 D10 ACCEPTED PRODUCTS .................................................................................................................. 61 SECTION S -SANITARY SEWER ................................................................................................................ 63 S1 SYSTEM CAPACITY ............................................. ....................................................................... 63 S2 METHODOLOGY OF ANALYSIS.................................................................................................. 63 S2.1 Existing Sanitary Sewer Systems ......................................................................................... 63 S3 NEW SANITARY SEWER SYSTEMS ................................... ........................................................ 63 S3.1 Average Daily Flow (Dry Weather) ........................................................................................ 64 S3.2 Peak Dry Weather Flow (PDWF) ........................................................................................... 64 S3.3 Infiltration Rate ........................................... .......................................................................... 64 S4 PIPE FLOW FORMULAS.................................................................................................... ......... 65 S5 MANHOLES............................................................................................................................... 65 S6 HYDRAULIC LOSSES ACROSS MANHOLES.............................................................................. 65 S7 TEMPORARY CLEAN-OUTS..................................................................................... ................... 66 S8 MINIMUM PIPE DIAMETER ....................................................................................................... 66 S9 VELOCITIES............................... ................................................................................................ 66 S10 MINIMUM GRADE.................................................................................. .................................... 66 S11 MINIMUM DEPTH OF COVER.................................................................................................... 67 S12 CURVILINEAR SEWERS ............................................................................................................. 67 S13 SEWER LOCATION/CORRIDORS ................................................. ............................................. 67 S14 UTILITY SEPARATIONS .............................................................................................................. 67 S15 SERVICE CONNECTIONS........................................................................................................... 68 S16 SANITARY PUMP STATIONS................................... ................................................................... 68 S17 FORCE MAINS ................................................................................................................ ........... 71 S18 AERIAL BRIDGES AND INVERTED SIPHONS ............................................................................ 72 S19 ACCEPTED PRODUCTS........................................... ................................................................... 72 SECTION W -WATER ............................................................................................................... ................. 73 W1 WATER DISTRIBUTION SYSTEM ............................................................................................... 73 W1.1 Community Water Supply ...................... ........................................................................... 73 W1.2 Private Wells...................................................................................................... ................ 73 W2 DOMESTIC DEMANDS............................................................................................................... 73 W2.1 Residential Demands..................... ................................................................................... 73 W2.2 Industrial, Commercial and Institutional Demands........................................................... ..... 74 W2.3 Hydraulic Calculations.............................................................................................................. 74 City of Maple Ridge Design Criteria Manual Contents 4 September 2015 W3 FIRE FLOW DEMANDS ............................................................................................................. . 74 W3.1 Properties Not Protected by Sprinklers ................................................................................... 74 W3.3 Properties Protected by Sprinklers ....................... ................................................................... 75 W4 WATER PRESSURES ............................................................................................................. .... 75 W5 HYDRAULIC NETWORKS ........................................................................................................... 75 W6 PIPE MATERIAL ......................................... ................................................................................ 76 W7 CORROSITIVTY INVESTIGATION...................................................................................... .......... 76 W8 DEPTH OF COVER...................................................................................................................... 76 W9 WATERMAIN GRADES .......................... ..................................................................................... 77 W10 CLEARANCE WITH SEWER PIPES................................................................................ ............. 77 W11 VALVES ..................................................................................................................................... 77 W12 HYDRANTS...................... .......................................................................................................... 78 W13 AIR VALVES........................................................................... .................................................... 78 W14 BLOW-OFFS ............................................................................................................................... 78 W15 THRUST BLOCKING AND JOINT RESTRAINTS.......................................................................... 79 W16 CHAMBERS................................................................. .............................................................. 79 W17 SERVICE CONNECTIONS........................................................................................................... 79 W18 WATER METERS........................................................................................................................ 80 W19 WATER SYSTEM LOCATION/CORRIDORS ................... ............................................................. 80 W20 PRVS, PRESSURE ZONES AND PUMPS ................................................................................... 80 W21 CHECK VALVES ......................................................................................................................... 80 W22 TEST POINTS AND CHLORINATION .................... ...................................................................... 81 W23 ACCEPTED PRODUCTS........................................................................................................ ...... 81 SECTION LT – STREET LIGHTING AND TRAFFIC CONTROL..................................................................... 83 LT1 GENERAL ........................................................ .......................................................................... 83 LT2 ILLUMINANCE AND CONFIGURATION ...................................................................................... 83 LT3 LUMINAIRES AND POLES ......................................................................................................... 84 LT4 UNDERGROUND DUCTS ....................................... .................................................................... 84 LT5 CIRCUIT SIZE .............................................................................................................. ............... 84 LT6 INTERCONNECTION CONDUIT .................................................................................................. 85 LT7 DECORATIVE STREET LIGHTING.................... ........................................................................... 85 LT8 TRAFFIC CONTROL .................................................................................................... ................ 85 LT8.1 General .............................................................................................................................. 85 LT8.2 Signal Timing ..................................................................................................................... 86 LT8.3 Design Components...................................................... .................................................... 86 SECTION TP – STREET TREE AND BOULEVARD PLANTING .................................................................... 87 TP1 GENERAL .................................................................................................................................. 87 TP2 PLANTING REQUIREMENTS....................................... ............................................................... 87 TP3 PLANT SPACINGS.................................................................................................................. .... 87 TP4 MINIMUM TREE PLANTING CLEARANCES ............................................................................... 87 TP5 SPECIES SELECTION.................................................. ............................................................... 88 City of Maple Ridge Design Criteria Manual September 2015 Page 1 SECTION G – GENERAL All design and construction details for city infrastructure services shall be in accordance with the Design and Construction Documents (Design Criteria Manual, Supplementary General Conditions, Supplementary Specifications and Supplementary Standard Detail Drawings), and with the most recent Master Municipal Construction Documents Volume II (MMCD), as adopted by the City, all referred to in the Subdivision and Development Servicing Bylaw. Much of the City’s infrastructure has been designed using engineering standards that were applicable at the time of construction. The most current Design and Construction Documents (as amended from time to time) are to be used when designing all new infrastructure and assessing the adequacy of existing infrastructure. Should the existing infrastructure not meet the current criteria, the Design Engineer will be responsible to provide justification of the non-conformance. This nonconformance must be submitted for review and acceptance by both the Design Engineer and the City. Acceptance by the City does not relieve the Design Engineer of liability associated with the design of infrastructure. G1 INTRODUCTION The purpose of this section is to outline the minimum standards and requirements of the City for the design and record drawing submissions for engineering works. Quality design and record drawings are expected. When municipal works are to be constructed, the Proponent, Design Engineer or Consultant shall arrange a predesign meeting to ensure they possess the current City standards, specifications and policies. The review of any design or record drawing must be completed to the City Drawing Standards. Incomplete or substandard submissions may be returned to the Developer or Design Engineer without comment on the drawings and with a short letter of explanation. A subsequent re-submission that remains incomplete or substandard may result in a request to meet with the Proponent, Design Engineer or Consultant, and the Manager of Infrastructure Development or Municipal Engineer. For full resubmissions, the City at the discretion of the Municipal Engineer, may require additional review fees. Please contact the Engineering Department for clarification or any questions. All submissions shall comply with all applicable requirements of the following City of Maple Ridge bylaws and their applicable schedules: (a) The current “Subdivision and Development Servicing Bylaw” (b) The current “Zoning Bylaw” City of Maple Ridge Design Criteria Manual SECTION G -GENERAL September 2015 Page 2 G2 SURVEY INFORMATION All surveys shall be conducted in a manner so as not to create a nuisance to traffic or the public and in accordance with the “Traffic Control Manual for Work on Roadways” and WorkSafeBC policies. The permission of the registered owner(s) is required prior to entering private property. All elevations shall be from the Geodetic Datum (NAD83 CSRS). Information regarding the location and elevation of benchmarks or monuments may be obtained from the Engineering Department. Originating benchmarks and survey monuments in the immediate area shall be noted on all plans as well as those to be established in the work. Copies of legible field notes shall be made available to the City upon request. Centrelines (or offset lines) are to be marked and referenced in the field and all chainages shall be keyed to the legal posting (may not apply if by GPS). All existing items such as monuments, manholes, catchbasins, fire hydrants, poles, existing dwellings, transit stops, fences, trees, hedges, and unusual ground shall be noted as required. Where applicable, cross-sections shall be required. The sections shall include centreline, edge of pavement or gutter line, edge of shoulder, ditch invert, top of ditch, property line, driveway letdowns and an existing ground inside property line. In urban areas the chainage shall be as given by the Engineering Department or if acceptable, as established by previous engineering designs. Generally, chainage shall increase from left to right and from bottom to top on a drawing. North shall be at the top or right side of a drawing. G3 DRAWING SUBMISSION All drawings shall be prepared in accordance with the following requirements and all other applicable requirements of this Schedule:  All Civil drawings shall be signed and sealed by a Professional Engineer registered in British Columbia.  Street tree and boulevard planting plan shall be signed and sealed by a Landscape Architect registered by the British Columbia Association of Landscape Architects.  Show Geodetic data (benchmark) and vertical datum on all drawings containing survey elevations.  The City project number must be noted in the lower right-hand corner (AutoCAD digital standard drawing sheets, City logo and standard drafting sample drawings are available from the Engineering Department upon request). City of Maple Ridge Design Criteria Manual SECTION G -GENERAL September 2015 Page 3  Clearly identify the works in sufficient detail. For projects that are contained to a single sheet and approved by the City, road cross-sections may be drawn by hand, provided they are of good quality and clarity.  All new works are to be drafted in bold lines.  Notes pertaining to the construction of a service are to be shown on that service drawing.  Design baseline is to be referenced to legal lot lines and illustrated on each sheet. Chainages are to be shown on profile in even 10m intervals. Points on profile should line up with identical points on plan below. If design baseline curves, at least one point on profile must line up with identical point on plan below.  Offsets are to be shown to both sides of the road allowance or to one side with the road allowance width annotated. Offsets are required for all mains, conduits, manholes, headwalls, hydrants, horizontal bends, gate valves not flanged to tee, blow-offs, street lights, and horizontal pipe deflections. Offsets must be shown from property lines.  Plans shall show the legal layout of roads and properties, including lot and house numbers, and lot frontage distances. Show lot numbers with a plot height of 3.5mm and a pen width of 0.35mm. Show existing house numbers with a plot height of 2.5mm and a pen width of 0.25mm. Show lot frontage dimensions (to the nearest 0.001m) with a plot height of 1.8mm and a pen width of 0.25mm. Do not show interior property distances. Also, show all registered statutory rights-of-way. A copy of a digital legal cadastral map is available from the Engineering Department upon request. A complete set of engineering design drawings shall include, in the following sequence: G3.1 Cover sheet Noting the Proponent, Design Engineer or Consultant's name, address, telephone number and fax number, the City file number, the legal description of the lands involved, a site plan at a 1:5000 scale, and an index. The site plan shall note all proposed roads and the proposed subdivision layout. The cover sheet may be utilized to show the drainage catchment area. A copy of the drainage catchment area map must also be attached to the drainage calculations. G3.2 Key Plan The Key Plan shall be at a 1:500 scale and shall note all proposed services, including street lighting and all non-standard connection offsets. If more than one sheet is required, note the westerly or southerly portion first and identify as Key Plan “A” with additional plans noting “B” and “C”, etc. The development site is to be outlined with a bold line. City of Maple Ridge Design Criteria Manual SECTION G -GENERAL September 2015 Page 4 If a profile drawing is not required for a utility, then the service connection depths and inverts are to be noted on the Key Plan. G3.3 Storm Water Management and Lot grading Plan The Lot Grading Plan shall be at 1:500 scale and identified as per the key plan system if more than one sheet is required. The following information must be included: a) pre-development and post-development topography at maximum 1m intervals with legal mapping, This topography shall extend a minimum 30m outside the development site b) all existing (un-circled) and proposed (circled) lot corner elevations c) all elevations along property line where changes in slope will occur d) the proposed building envelope with the Minimum Building Elevation (MBE), elevation of lower floors and yard at corner of building e) the slope of the lot (directional arrow), noting the minimum grade on the lots and lot dimensions f) the minor (1:10 or 1:25 year) storm sewer system with the flows noted per section and the accumulated flows from all upstream sections. Provision must be made for upstream development potential where applicable g) the major (1:100 year) storm sewer system with the flows noted per section and the accumulated flows from all upstream sections. Where the hydraulic grade line of the major flow is within the storm sewer or below the ground surface, a note identifying its location shall be marked on the drawings. Overland or surface flows shall be identified with a wide directional arrow. Provision must be made for upstream development potential where applicable h) no surface drainage shall be proposed to flow off-site over adjacent lands unless off-site works are proposed and in compliance with municipal standards. Attempts should be made to “meet” existing elevations along the development boundary i) fill over 0.45m is to be shaded, with fill over 1m highlighted j) retaining walls that will be needed, including extent of walls and elevations of top and bottom of walls The Storm Water Management Plan shall be at 1:2500 scale and identified as per the key plan system if more than one sheet is required. The following information must be included: City of Maple Ridge Design Criteria Manual SECTION G -GENERAL September 2015 Page 5 a) points along the subdivision project boundaries that receive run-off from offsite drainage areas b) pre-development and post-development drainage network (pipes, culverts, inlets, manholes, swales, open channels, etc.) and catchments tributary to each pipe or culvert inlet, as well as the following information in tabular format on the drawings:  length, size and slope of each pipe  tributary area and run-off coefficients  calculated minor and major flow rates and capacities of each reach  where the hydraulic grade line of the major flow is within the storm sewer or below the ground surface, a note identifying its location shall be marked on the drawings  overland or surface flows shall be identified with a wide directional arrow  inlet and total area for off-site areas tributary to a storm sewer or culvert c) existing and future land use classification d) pre-and post-development run-off control measures e) provision must be made for upstream development potential where applicable and where required for "latecomer" service, all excess or extended services in bold f) a legend noting all items proposed in the Storm Water Management Plan g) all catch basins and lawn basins are to be shown with surface flow arrows h) storm connections to be shown on plan i) include either in a separate report or on the drawings all storm water calculations j) applicable general notes should also be included G3.4 Road and Water Plan and profile drawings shall show all grades, inverts, curbs, catch basins, radii, valves, hydrants, bends, ground profiles at property lines, centreline of existing road, elevations at curb returns and at quarter points, wheelchair letdowns, bus stops, trees, fences, retaining walls, etc. The scale shall be 1:500 for plans, and 1:500 horizontal and 1:50 vertical for profile. The full pipe shall be shown for the watermain on the profile. All crossover points with sewers shall be noted and where the watermain is below any sewer, or is less than 0.5m above any sewer. On the plan, a list of the watermain fittings is to be “boxed in” for each location and tied to chainages. On the profile, the fittings are to be shown and the chainages indicated. City of Maple Ridge Design Criteria Manual SECTION G -GENERAL September 2015 Page 6 Catch basins are also to be shown with the chainage and grate elevations. All curb returns and cul-de-sac data to be shown with gutter line profiles. Design elevations are to be shown at every 10m intervals on straight vertical alignments and 5m intervals on curved vertical alignment. Any gutter elevations with different than 2.5% standard cross-fall are to be noted on the profile at each station and on the crosssection drawings. G3.5 Storm and Sanitary Sewers Plan and profile drawings shall show grades, inverts, manholes, catch basins, etc. The scale shall be 1:500 for Plan, and 1:500 horizontal and 1:50 vertical for profile. Symbols to denote the service connection elevation at the property line shall be shown on the profile plan, as well as the minor and major system hydraulic grade lines. The full pipe shall be shown on the profile. All storm mains (plan and profile), manholes (in profile), and lot connections to be shown with a continuous line. All sanitary mains (plan and profile), manholes (in profile), and lot connections to be shown with a long dashed line. All manhole rim elevations are to be noted. If mains are larger than 450mm diameter, manhole size is required on profile beside manhole rim elevations. All manhole numbers shall be marked up by City staff on the ‘First Design Submission’. All lot service connections to have individual dimensions from nearest property line (no typicals accepted). Flow arrows are to be shown on all storm and sanitary pipes on plans. All manhole numbers shall contain the service abbreviation (‘S’ or ‘D’), the basin area prefix and unique manhole numbers within each area. G3.6 Road Cross-Sections Road cross-sections shall be scaled at 1:250 horizontal and 1:25 vertical and shall note the proposed elevations of the road centreline. Cross-sections are required at 20m intervals on flat and gentle terrain and at 10m intervals on steep and rough terrain. In addition to typical spacing cross-sections at all driveway crossings, crosswalks, and intersections shall be shown. Additional sections may be required or requested where excessive cuts or fills are involved. Each sheet shall have a typical road section showing details of road structures, side and back slopes, surface treatment, cross-falls and dimensions. G3.7 Ornamental Street Lighting Plan Ornamental Street Lighting Plan shall be a 1:500 plan of the proposed street lighting, signed and sealed by a Professional Engineer. The plan shall include Illuminating Engineering Society (IES) calculations and general notes with reference to the City of Maple Ridge Design and Construction Documents and MMCD Platinum Edition Volume II and the City approved make and luminaire model. Street light pole heights, luminaire type, and wattage are required. Pole colour is also required on street light plan. City of Maple Ridge Design Criteria Manual SECTION G -GENERAL September 2015 Page 7 G3.8 Street Tree and Boulevard Planting Plan Street Tree and Boulevard Planting Plan shall be a 1:500 plan of the proposed street tree and boulevard treatment designed, signed and sealed by a Landscape Architect. The plan shall show: a) the location of the plant material with respect to curb, sidewalk, underground utilities, overhead utilities, driveway location, mailbox locations, and street lights b) planting detail as per City of Maple Ridge Design and Construction Documents and MMCD Platinum Edition Volume II pertaining to street tree and boulevard plantings c) plant list showing quantity, botanical name, common name and size of proposed trees d) surface treatment of proposed boulevard strip e) notation on drawing that “Final location and species selection shall be to the satisfaction of the Environmental Technician or Parks Department Manager” f) standard notes as required by the Landscape Technician or Parks Manager G3.9 Construction Details Construction details shall show all proposals for construction which are not covered or specifically detailed in the City of Maple Ridge Design and Construction Documents or MMCD Platinum Edition Volume II. Where City or MMCD standards apply the Standard Detail Drawing or Supplementary Standard Detail Drawing number may be quoted. It is not always necessary to include details for which there is a Standard Detail Drawing or a Supplementary Standard Detail Drawing. G3.10 Notes for Construction General notes for construction shall be on each specific works construction drawing or separate notes drawing. G3.11 Seal and Signature The Design Engineer’s original seal and signature shall be placed on all sheets of all design submissions except for the street tree and boulevard planting plan which shall be signed and sealed by a registered Landscape Architect. Failure to do so will result in the plans being returned without comment. G3.12 Other Requirements Notwithstanding the previously detailed requirements, the following additional information is to be noted in design submissions. City of Maple Ridge Design Criteria Manual SECTION G -GENERAL September 2015 Page 8 a) the size, grade, inverts, and type of material on profile sections b) the locations, offsets, curvatures, size and identification of the mains noted on the plan sections c) the clearance between mains at all cross-over points d) all existing structures, including houses, sheds, fences, wells, septic tanks and fields, shall be shown on the appropriate drawings, with a notation indicating their fate (i.e. to be removed, filled, etc.) e) in rural subdivisions with an open ditch drainage system, note the lengthened size of future driveway culverts and depth of cover required to conform to the design f) survey monument locations and indicate which ones are to be relocated or re-established G3.13 First Submission The first complete design submission shall consist of: a) one complete PDF version, files should be kept to a maximum of 9MB if necessary use appropriate separation of sections b) two complete sets of drawings c) two additional storm water management plans d) geotechnical report to verify road structure design (soils reports are required on all new road construction design), The report is to include a test for corrosiveness when installing utilities e) geotechnical report to verify conditions for the design of rainwater management facilities f) all applicable utility and rainwater management calculations for municipal services including water, sanitary, storm water management and lighting g) a complete construction estimate G3.14 Submission Revisions Subsequent design submissions requiring changes to the previous submission shall consist of: a) one complete PDF version, files should be kept to a maximum of 9MB if necessary use appropriate separation of sections City of Maple Ridge Design Criteria Manual SECTION G -GENERAL September 2015 Page 9 b) two complete sets of drawings c) a revised construction estimate d) all submissions subsequent to first submission shall have any changes made by the Design Engineer, which are in addition to “Red Line” comments noted by the City, highlighted with yellow e) the Design Engineer must address items “Red Lined”. Failure to do so will result in submissions being returned G3.15 Final Submission The final submission for City distribution shall consist of: a) one complete PDF version, files should be kept to a maximum of 9MB if necessary use appropriate separation of sections b) three complete sets of drawings c) two additional storm water management plans d) one additional set of the water system design plus a key plan e) final construction digital drawings in AutoCAD format f) a sealed construction estimate G4 CONSTRUCTION COST ESTIMATE The Engineering Department may provide a detailed format for the breakdown of the construction cost estimate. These items and costs may be reviewed and amended where necessary. G5 RECORD DRAWING SUBMISSION The following procedures shall be followed in the submission of Record Drawings: a) The Developer or Design Engineer shall submit one complete set of paper prints, except for the road cross-section sheets. This submission shall include the lot grading plan for the City’s review. b) One marked-up set of Record Drawing paper prints will be returned to the Developer or Design Engineer for revision. If there are minor changes, the electronic record drawing file may be revised. If amendments are numerous, it is likely that the Developer or Design Engineer will be requested to resubmit one set of revised paper prints for a second review. The City record number will have been noted on each drawing for identification of the electronic record drawing. City of Maple Ridge Design Criteria Manual SECTION G -GENERAL September 2015 Page 10 c) Record drawings shall be presented as follows: Detailed plan profile drawings for water, sanitary, storm and roadworks. Elevations, inverts and offsets to show the works as constructed. The profile drawings for the utilities shall state the pipe material and classification used. (i) Where required in the design submission, the stormwater management plan, including lot grading and rainwater management features shall be provided. The plan shall note the elevations at all lot corner pins, lawn basin and catch basin rims and swale inverts. Grades between lot corners and control points shall be uniform unless indicated otherwise on the plan (to a tolerance of +/-150mm). In no case shall the lot grade be less than the minimum. (ii) Street light drawings shall indicate make, model and type of luminaire unit and locations of service bases and photocells, and underground conduit locations. (iii) Plans of details for which there is no City standard (pump stations etc.). (iv) All details such as typical sections shall be shown on the drawings to which they apply. (v) In all cases notes with instructions to the Contractor are to be removed or amended to indicate the results of construction. Previously existing works that have been deleted as a result of construction, or reconstructed in accordance with design shall be removed or amended to show works as constructed. It is intended that the Record Drawings shall show the works as they have been constructed in order to provide accurate and detailed information when adding to, or maintaining, the works shown on the plans. (vi) The Record Drawings shall be submitted as shown in the standard drawings. Sample digital drawings which are available from the Engineering Department upon request. (vii) Street trees and boulevard plantings shall indicate location, names and sizes. d) When the City is satisfied with the Record Drawings submission. the Developer or Design Engineer will be requested to submit the following: (i) one complete PDF version, files should be kept to a maximum of 9MB. If necessary use appropriate separation of sections; (ii) AutoCAD.dwg files in the current version used by the City:  use the 4 digit City record number as the file name  each record drawing to be a separate file  no external references to be used  model space only  to minimize the electronic file size (avoid using solid shade or dense hatch patterns etc.)  use only standard AutoCAD text, fonts and shape files  color of entities by layer only  all blocks built on Layer 0 with color by layer  manhole numbers as prefixed by the City City of Maple Ridge Design Criteria Manual SECTION G -GENERAL September 2015 Page 11  the revision column to indicate ‘record information’ complete with date One set of quality paper prints with the following certification: “I certify this drawing represents the works and services as designed, installed, and inspected.” The signature and seal shall be by the engineer who personally performed or personally supervised the required inspections. Record Drawings must be submitted to the City within one (1) month of issuance of the Certificate of Completion. In addition to the 10% maintenance security, 10% of the construction cost or $5,000, whichever is greater, will be applied for Record Drawings. The Record Drawing security will be withheld by the City until satisfactory Record Drawings are complete. Any securities held for the submission of Record Drawings will be in addition to the required maintenance securities. G6 SEISMIC DESIGN STANDARDS There are specific areas in the Maple Ridge that are vulnerable to seismic events where seismic design standards may be required for underground piping systems. When identified by a geotechnical report the Design Engineer shall contact the City to determine the applicable seismic design standards for underground utilities for the particular project. City of Maple Ridge Design Criteria Manual SECTION G -GENERAL September 2015 Page 12 THIS PAGE INTENTIONALLY LEFT BLANK City of Maple Ridge Design Criteria Manual September 2015 Page 13 SECTION R – ROAD R1 INTRODUCTION All roads in the city shall be designed in accordance with the recommended practice as outlined in the latest edition of the “Manual of Geometric Design Guide for Canadian Roads” as published and amended from time to time by the Transportation Association of Canadian (TAC) or as stated elsewhere in this manual or as accepted by the Municipal Engineer. R2 CLASSIFICATIONS The City will advise the Developer of the classification of each road within or adjacent to any particular development, generally in accordance with the Subdivision and Development Servicing Bylaw and identified in the Strategic Transportation Plan. The design of these roads shall be in accordance with the applicable standard drawing for each road classification. Road classifications are generally in accordance with the TAC design classification system as follows:Arterial -An arterial road is a highway with the primary function of carrying through traffic from one area to another with as little interference as possible from adjacent land uses. An arterial road may provide direct access to property as a secondary function when alternate access is not available. Collector -A collector road is a highway with the primary function of distributing traffic between arterial, other collector and local roads within an area. Collector roads front civic, industrial, commercial or multifamily properties, provide on street parking and direct access to properties. Local -A local road is a highway with the primary function of providing direct access to properties. Local roads normally connect to other local roads or to collector roads. The above classifications are further divided into urban and rural classifications. Road classifications also include the following: Lane -A lane (also called public lane or alley) is a roadway with the primary function of providing land access, typically at the rear of abutting properties. Lanes are not intended to carry through traffic. For properties fronting collector or arterial roads, rear lanes can eliminate the need for front driveways. Walkway and Bikeway -Walkways and bikeways are paths which follow routes independent from motor vehicle roadways, sidewalks and bike lanes. Bicycle Facilities -Include Off-Street Pathways, Neighbourhood Bikeways, Painted Bicycle Lanes and Shoulder Bikeways as defined in the City of Maple Ridge Strategic Transportation Plan. City of Maple Ridge Design Criteria Manual SECTION R -ROAD September 2015 Page 14 R3 GRADES The maximum longitudinal grades generally shall be as follows: a) local residential roads: rural 12% urban 12% b) cul-de-sac 12% c) collectors, industrial and commercial roads 10% d) arterial roads 8% Fire platforms are required where road grades exceed 8% for more than 100 metres:  without hydrant coverage (20m long; 7m clear width; maximum grade 2.5%)  with hydrant coverage (15m long; 6m clear width; maximum grade 5%)  a cross street or intersection would be considered adequate as a fire platform so long as both streets would have a minimum carriage width of 7.0m Where topographical constraints restrict the attaining of the minimum or maximum grade, the Municipal Engineer may consider variations to the above limits. Consideration may be given to increased road widths, parking restrictions and accessibility issues for roads that exceed the accepted grades. Where sidewalks are required, refer to sidewalk section. R4 CROSS-SLOPES Standard cross-slopes on streets shall be 2.5%, from the crown to the toe of the gutter and with one-way cross falls, subject to the acceptance of the Municipal Engineer. Maximum 4% cross-slopes are permitted in exceptional circumstances including road widening and road rehabilitation. R5 HORIZONTAL AND VERTICAL CURVES Horizontal curves shall be governed by the design speed of the as follows:  Urban locals 50km/h  Urban collectors 55km/h  Urban arterials 66km/h  Rural locals 55km/h  Rural collectors 55km/h  Rural arterials 66km/h Urban arterial and all rural roads with vertical curves shall be designed for an additional 10km/h above the horizontal curve design speeds as shown above. City of Maple Ridge Design Criteria Manual SECTION R -ROAD September 2015 Page 15 The criteria contained in the TAC “Manual of Geometric Design Guide for Canadian Roads” concerning horizontal and vertical curves shall be followed. Maximum allowable super-elevation for urban arterial, rural collector and arterial roads shall be 4%. No super-elevation is required for any local roads and urban collector roads. R6 CURB RETURNS Suggested curb return radii shall be as follows: 90 degree Intersection with Local Collector Arterial Locals 7m 9m Design Industrial Locals 9m 9m Design Collectors 9m 9m Design Arterial Design Design Design All intersections will require a turning template check using the appropriate design vehicles, roadway configuration and classifications. Curb return radii for arterial intersections require specific designs taking into account projected volumes, turning movements, truck traffic, transit and emergency services, whether turning lanes are provided, etc. The Municipal Engineer may require variations to protect pedestrians and to preclude instances where awkward geometry may otherwise result in vehicles turning into the path of other oncoming vehicles. Corner truncations shall be required at all street corners to maintain a minimum 4m distance from curb face to property line. R7 CUL-DE-SACS The maximum road length for a cul-de-sac, as measured from the edge of the intersecting through road to the centre of the cul-de-sac bulb is 200m. Design of cul-de-sacs shall follow the applicable standard drawing. The following minimum radii shall apply: Road Pavement Radius (m) ROW Radius (m) Rural 11 14 Residential 11 14 Multi-Family Residential 11 14 Commercial 14 17 Industrial 15 18.5 City of Maple Ridge Design Criteria Manual SECTION R -ROAD September 2015 Page 16 The design of cul-de-sacs is not limited to the above and the designer may propose alternatives provided that good engineering practice is followed. Alternative designs are subject to review by the Municipal Engineer. R8 TEMPORARY TURNAROUNDS Temporary turnarounds shall be designed for roadways longer than 100m which are to be extended in the future. Temporary turnarounds shall be of a hammerhead design and not impact private property or driveway access as shown in the applicable standard drawing. R9 INTERSECTIONS Particular attention shall be given to the design of all intersections. The designer should employ good engineering practice as set out by TAC in assessing the following concerns:  approach grades and grade transitions  crossing sight distance  design speeds  intersection cross-slopes  curb returns  intersection alignment  curb bulges Specifically, grades of major and minor roads at intersections shall be adjusted where topographic or other conditions dictate the use of maximum or near maximum permissible grades. Such adjustments are essential to provide reasonable stopping opportunities during extreme roadway icing conditions. R10 CROSS SECTION CONSIDERATIONS The basic design road width and thickness shall be determined by: a) road classification b) applicable standard drawing c) results of soils tests and analysis of Benkleman Beam tests, or by the CBR asphalt pavement design method (See also Section on Road Base and Pavement Design) Maximum side slope in earth fills or cuts shall be 1.5H:1V. Lesser grade slopes shall be used where unstable soil conditions are encountered. If cut or fill slopes extend beyond the road allowance, a right-of-way sufficient to support the slope plus 2m shall be registered in favour of the City. In developed urban areas, wherever the side slopes beginning at a point 600mm from the back of the sidewalk create a depth of vertical cut or fill at the existing property line in excess of 600mm at 2H:1V slope, a concrete retaining wall shall be constructed unless otherwise City of Maple Ridge Design Criteria Manual SECTION R -ROAD September 2015 Page 17 permitted by the Municipal Engineer. Retaining walls, if required, shall be designed by a Professional Engineer adequately drained, contain a vehicle and pedestrian access to each property, and be equipped with railings. Retaining walls shall be located on the land which is being supported. Where applicable, the design shall ensure that the road cross-sections are designed to accommodate the major flood path routing. R11 ROAD BASE, PAVEMENT DESIGN AND PATCHING The structural design of the road pavement shall be adequate for an expected road life of 20 years under the expected traffic conditions for the class of road. Existing Road Upgrading Road construction and asphalt overlay design shall be based on the analysis of the results of the Benkleman Beam tests and test holes carried out on the existing road which is to be upgraded, or by the California Bearing Ration (CBR) asphalt pavement design method. New Road Construction The design of new roads shall be based on the results of the analysis of materials from test holes dug on the proposed road site at representative intervals, or by the CBR asphalt pavement design method. Trench Patches The extent of surface repair for all longitudinal service trenches will include the full lane width on arterial and collector roads or to road centerline for local road classifications. Multiple service trenches closer than 8m apart must be completed as a single patch. Test holes and samples shall be undertaken by a qualified soils test company and all reports shall be signed and sealed by a qualified Geotechnical Engineer. Where the Benkleman Beam design method is used, the Maximum Seasonally Adjusted Design Deflections (mean plus two standard deviations) shall be as follows: Classification Min Sub-base mm Min Base mm Min Asphalt Max Seasonally Adjusted Design Deflections (mm) Base mm Surface mm Base Pavement Urban Arterial 500 100 50 50 1.20 1.00 ~ 0.70 Urban Collector 300 100 40 40 1.90 1.40 ~ 1.10 Urban Local 300 100 40 40 2.50 1.70 ~ 1.40 Urban Ltd Local 300 100 40 40 2.50 1.70 ~ 1.40 Lane 200 100 40 40 3.00 1.70 ~ 1.40 Rural Arterial and Collector 300 100 40 40 1.50 1.20 ~ 090 Rural Local 300 100 40 40 3.30 1.70 ~1.40 Rural Ltd Local 300 100 40 40 3.30 1.70 ~ 1.40 Industrial Local and Collector 300 100 50 50 1.10 1.00 ~ 0.70 City of Maple Ridge Design Criteria Manual SECTION R -ROAD September 2015 Page 18 Note 1: Recommended sub-base and base thickness are minimum requirements only. Site conditions may dictate greater thickness of granular material to achieve design rebound. Note 2: Where rebound readings are greater than the design reading for the base course, the subgrade should be investigated for potential weakened areas. Note 3: The standard pavement material is hot mixed, machine laid, asphaltic concrete. Note 4: When the base and surface courses are required, the surface course is to be withheld until building construction is complete or the maintenance period has expired. R12 SPECIAL DESIGNS Whenever compressible soils are present or when maximum probable spring rebound values greater than 12mm, or CBR values less than 2% are identified, standard design procedures for flexible and rigid pavements cannot be applied. A special design, usually involving special treatment of the ground, is indicated and the special design proposed shall be supported by detailed soils testing and evaluation by a Professional Engineer. R13 DRIVEWAYS R13.1 Residential Access to Arterial and Collector roads Residential driveway access to an arterial road is not permitted. Wherever physically possible, alternate access shall be dedicated to preclude residential driveways accessing directly onto arterial roads. Residential driveway access to town center collector roads from properties with an area less than 370m2 is not permitted, alternate access shall be dedicated to preclude residential driveways accessing directly onto collector roads. R13.2 Number of Driveways One primary driveway is permitted per property. A secondary driveway requires approval by the Municipal Engineer and may be permitted to access land with a physical barrier such as conservation area or steep slope, upon demonstrated need to support the intended land use, or for emergency response. Where a lot abuts roads of different classifications, the primary driveway shall be located to access the road of the lower classification and secondary access from the same or higher classification. Driveway crossings from the road pavement to the property line shall conform to the applicable standard drawing. City of Maple Ridge Design Criteria Manual SECTION R -ROAD September 2015 Page 19 R13.3 Driveway Location and Width a) Single family urban development’s driveways shall have a minimum width of 4m and a maximum width of 6m and in no case exceed 50% of the frontage width. Driveways on corner lots shall be no closer than 7.5m from the lot corner nearest the intersection. All urban residential driveways with barrier curbs will require letdowns to City standards. b) Commercial, industrial, institutional, comprehensive and multifamily development driveways shall have a minimum width of 6m to a maximum of 9m. For access with center islands the access in shall have a minimum width of 6m and access out shall have a minimum of 4m. Driveways on corner lots shall be located no closer than 15m from the property line of the adjoining road. Where a corner lot adjoins a road of different classification, the principal driveway shall be constructed so as to access the road of the lower classification and emergency access to the higher classification, except for service stations where access may be provided from both adjoining roads. R13.4 Driveway Grades Driveway access grades shall be designed to permit the appropriate vehicular access for the zone, without “bottoming-out” or “hanging-up”. From edge of pavement to property line, the driveway shall follow proper boulevard slope to drain towards the road. For the first 10m on private property, the maximum grade shall be limited to 10% if accessing a collector, or if a commercial or industrial zone. R13.5 Driveway Letdown and Curb Return At the discretion of the Municipal Engineer, access to large parking areas, commercial, industrial and multifamily developments may be by curb returns rather than a driveway letdown. The Municipal Engineer may require deceleration and acceleration lanes for access off major roads for safety reasons and to minimize disruption to traffic flows. Design of such access shall follow the recommendations of the current Ministry of Transportation and Highways, Highway Engineering Branch “Design Manual” and TAC “Geometric Design Guide for Canadian Roads”. R14 EMERGENCY ACCESSES In consultation with the Fire Department, the Municipal Engineer may require the installation of emergency accesses in urban developments in accordance with the applicable standard drawings. Such emergency access must be able to support a wheel axle load of 9.1 tonnes. Curb letdown shall be provided when an emergency access meets a road, which has a barrier curb. City of Maple Ridge Design Criteria Manual SECTION R -ROAD September 2015 Page 20 Rural emergency accesses or temporary emergency accesses in urban developments will require a special design. The travel surface may be of asphalt and fencing may not be required. However, vehicular restriction devices must be designed for each end, as required. Where there is reasonable expectation that a rural development will be urbanized in the near future, an urban standard emergency access will be required. R15 BOULEVARDS Street trees and boulevard plantings are to be of a species and spacing acceptable to the Environmental Technician or Parks Manager. Planting shall be in accordance with the applicable standard drawing pertaining to street tree and boulevard plantings. Installation of 350mm topsoil, turf and street trees in boulevards may be required by the Municipal Engineer prior to completion of house construction at the request of the Landscape Technician or Parks Manager where it appears that the boulevard treatment will not be upgraded in the near future. R16 SIGNAGE Unless the City directs otherwise, all traffic signage will be installed by the City at the Developer’s expense. Any pavement markings required will be the responsibility of the Developer and must be provided within a reasonable amount of time after paving. The Municipal Engineer may require the Developer to engage an engineering consultant to provide traffic signage and pavement marking drawings to the City. R17 CURBS, SIDEWALKS AND WALKWAYS R17.1 Curbs and Gutters All full urban roads shall be complete with concrete curbs and gutters on both sides of the road. Concrete curbs and gutters shall conform to the style identified in the applicable standard drawing for each road designation. All collector and arterial status roads shall be constructed with barrier curbs. All local roads shall be constructed with rollover curbs, except when adjacent to a separated sidewalk, identified as a 100 year surface drainage route, or on steep slopes, in which case barrier curbs shall be required. Where, barrier curbs are required on local roads transitions to rollover curbs shall be done through a minimum distance of 1.5m and all private driveways shall be incorporated with letdowns. Concrete banding or flow through curb sections shall be used for provision of Low Impact Development (LID) applications such as bio-swales or rain gardens. City of Maple Ridge Design Criteria Manual SECTION R -ROAD September 2015 Page 21 R17.2 Wheelchair Ramps Wheelchair ramps are required at all intersections and where deemed appropriate by the Municipal Engineer. The design for wheelchair ramps shall be in accordance with the applicable standard drawing. A side inlet catchbasin must be located to intercept road drainage in advance of the wheelchair ramp. This may influence road grade designs or cross slopes. All curb returns with sidewalk against curb shall be at least 2.0m wide at wheelchair ramp. Tactile warning strips are to be designed as shown in the applicable standard drawing. The Universal Design Guidelines for Outdoor Spaces prepared for the City of Maple Ridge and Pitt Meadows provides information and guidelines to accommodate all citizens. R17.3 Sidewalks Sidewalk requirements are stipulated by road classifications, and shall be designed as per the applicable standard drawing. a) If only one sidewalk or one row of street lights is required, they shall be placed at the side opposite to the power and telephone corridor. b) For cul-de-sacs, a sidewalk will be required on one side of the access road to the bulb portion to the first property line within the bulb. Where a walkway is proposed off the bulb portion, the sidewalk is to be extended around and connected to that facility. Where cul-de-sac is less than 100m long, it does not require sidewalk. c) All urban through roads, and all roads in commercial zones, shall require sidewalks on both sides. The clear width of sidewalk shall be 1.5m as shown in the applicable standard drawing. In exceptional circumstances a clear width of 1.2m is allowed around permanent features, subject to the approval of the Municipal Engineer. d) The requirements of two sidewalks on a single family residential local road may be relaxed by the Municipal Engineer if the road is not a pedestrian link to a trail, park or school and is not a continuation of a two sidewalk road. e) Two sidewalks are required on industrial roads unless approved by the Municipal Engineer. f) Sidewalks shall be continuous around curb returns and for a minimum of 1.5m after the curb return into roads not requiring sidewalks. g) The grade of the sidewalks shall be consistent with the grade of the road and crossfall shall be 2% sloping from the property line towards the curb. City of Maple Ridge Design Criteria Manual SECTION R -ROAD September 2015 Page 22 h) Crossfall may be permitted to vary up to +/-4% relative to the adjacent curb top to suit property elevations. Where the sidewalk grade slopes toward the property line, adequate drainage to the City’s storm drainage system shall be provided. i) Sidewalks that exceed 12% must consider accessibility options. j) Obstructions in the sidewalk should be avoided where possible. Sidewalk deflections are preferred for separated sidewalks and should be constructed to minimize sharp transitions. Alternatively flares can be used but must provide 1.2m clearance for the full panel length behind the obstruction (minimum 2.5m) and transitions should be 2:1 (minimum 2m). R17.4 Walkways Walkways shall be constructed in accordance with the applicable standard drawing. Walkway pavement width shall be 3m and walkway right of way width shall be 3m. Urban walkways shall be asphalt with chain link fencing on both sides and bicycle baffles or emergency access gates at both ends. Pathways that exceed 12% must consider accessibility options. R17.5 Handrails Handrails shall be constructed in accordance with the applicable standard drawing. Handrails shall be required for sidewalks and walkways where grades are in excess of 8% or where steps are provided or where grade separation exceeds 0.6m. Handrails may also be required along the top of major storm sewer outfalls, along walkways and sidewalks where steep or excessive side-slopes may be encountered, or in any location as deemed necessary by the Municipal Engineer where, in his opinion, the safety of pedestrian traffic or the protection of the public so requires. R18 BIKEWAYS AND EQUESTRIAN TRAILS Bikeways shall be designed in accordance with the latest edition of the “Geometric Design Guide for Canadian Roads” as published by Transportation Association of Canada. Equestrian trails shall be consistent with Schedule “F” of the City Official Community Plan (OCP) and the guidelines identified by the Equestrian Trail Council and Manager of Parks. R19 PAVEMENT MARKING AND STREET SIGNS Pavement markings and street signs shall be designed in accordance with the Transportation Association of Canada (TAC) guidelines. City of Maple Ridge Design Criteria Manual SECTION R -ROAD September 2015 Page 23 Where approved by the City bicycle facilities shall incorporate, green zones where high conflict zones occur between vehicles and bike facilities and red curbs at grade transitions between bike facilities. City of Maple Ridge Design Criteria Manual SECTION R -ROAD September 2015 Page 24 THIS PAGE INTENTIALLY LEFT BLANK City of Maple Ridge Design Criteria Manual September 2015 Page 25 SECTION D – DRAINAGE D1 INTRODUCTION The goal of the drainage design criteria is to standardize the procedures for designing drainage facilities in the City of Maple Ridge to reduce the potential risks to health, safety and property damage; minimize impacts on the natural environment; and provide a social and economic benefit to the community. To achieve the overall drainage goals, designs shall comply with current City bylaws, senior government guidelines and other conditions identified in other available documentation including Integrated Stormwater Management Plans, geotechnical or groundwater investigations. Stormwater management shall respect the form and character of the surrounding land and work towards mimicking natural drainage conditions while integrating protected natural drainage features including conservation land, watercourses, wetlands, ponds, channels and any necessary infrastructure including the minor and major storm facilities to address three tier stormwater management and water quality issues. D2 STORMWATER MANAGEMENT PRINCIPLES D2.1 Responsibility Drainage systems shall consider the analysis for the control of all rainfall events in consideration of the entire watershed and three tier principals. The design of the drainage system shall incorporate techniques to capture small events (Tier A), control runoff from larger events (Tier B) and provide adequate level of flood protection (Tier C). Additional criteria may be established through senior environmental agencies and applicable City bylaws when interfacing with watercourses, including but not limited to:  Watercourse setbacks, conservation and compensation areas.  Bank protection and stabilization to control erosion and downstream sedimentation.  Stormwater management facilities should consider recreational, environmental and aesthetic benefits as well as flow control and water quality.  All filling or soil removal activities in or around watercourses must be undertaken in accordance with City bylaws and senior government regulations.  Watercourse crossings shall consider flood protection and the preservation of existing fish passage in streams when determining the type, sizing, location and installation plans. All aspects must be approved by the City and comply with senior government agencies.  Sources of pollution shall be limited from all drainage systems with consideration to temperature, organic matter, toxic matter and sediment.  Base flows shall be sustained in watercourse to protect fish habitat. City of Maple Ridge Design Criteria Manual SECTION D -DRAINAGE September 2015 Page 26 The capacity of an existing municipal drainage system shall be reviewed to determine that it is adequate to receive the proposed design flows. Existing facilities which are undersized or inadequate to accept additional drainage must be upgraded at the Developer’s expense to accommodate the appropriate flows. A Stormwater Management Plan shall be submitted for all developments identifying the three-tier concepts; treatment for water quality, additional criteria, capacity upgrades and recommend a stormwater concept that is economically and environmentally justifiable for the development. Detailed designs shall be submitted following acceptance of the stormwater plan and include the operation and maintenance responsibility for stormwater drainage facilities. Designers shall contact the Engineering Department to obtain any existing information that may be of assistance to them. D2.2 Tier A Tier A events are small rainfall events that are less than half the size of the Mean Annual Rainfall (MAR) and represent approximately 90% of the annual rainfall. Capturing these small events from rooftops and paved surfaces at the source is the key to reducing runoff. This captured rainfall should be infiltrated, evapotranspired or re-used at the source. D2.3 Tier B Tier B events are larger rainfall events that exceed Tier A up to and including MAR, these events represent approximately 10% of the annual rainfall and result in the majority of the peak flows in downstream watercourses. Source control facilities shall store the runoff from impervious surfaces resulting from the large rainfall events and release it at a controlled rate of a 1:2 year forested flow to manage the rapid response of runoff from impervious surfaces. Source control facilities include detention/retention ponds, exfiltration trenches, dry wells, bio-swales, rain gardens and other acceptable methods suitable for reducing the rate of runoff and removing contaminants prior to release into the downstream drainage system. D2.4 Tier C Tier C events are extreme storm events that exceed Tier B rainfall events and may or may not occur in any given year. Tier C is separated into the minor and major system and must provide adequate conveyance for runoff from extreme storms without causing property damage or impacts to public safety. The minor system comprises all drainage facilities that detain and convey up to the 1:10 year event. The runoff from the minor storm is referred to as the minor flow and shall be detained and released at the 1:2 year predevelopment rate unless approved by the City. Conveyance systems shall accommodate the 1:10 year post development City of Maple Ridge Design Criteria Manual SECTION D -DRAINAGE September 2015 Page 27 flow. Minor system can include storm sewers, culverts, channels detention ponds/tanks, exfiltration trenches, dry wells, bio-swales, rain gardens and other acceptable methods suitable for reducing the rate of runoff. The major system comprises all drainage routes that are designed to accommodate runoff from the 1:100 year event and shall be contained within a public right of way or natural drainage channels capable of accepting the design flow. Where directed by the City the 1:100 shall be detained to a 1:10 year pre-development rate for upland areas. Roadways, overland flow paths, channels and watercourses shall be designed to ensure that the maximum hydraulic grade line is below the lowest existing or proposed minimum building elevation of any adjacent buildings. Surcharging at the inlet under the major flow is acceptable provided the headwater profile does not rise above the minimum building elevation. Major drainage routes shall be designed with adequate erosion and flood protection where surcharging is proposed. In the event that surface flow is not feasible or that the inlet facility is likely to be blocked or restricted, consideration shall be given to the sizing of the storm sewer system to accommodate the major flow. Developments that discharge to natural watercourses may be required to define the 1:200 year hydraulic grade line for pre-development and post-development conditions in the area to be developed and along affected watercourses downstream of the development. D2.5 Stormwater Management Plan Stormwater Management Plans identifying the drainage requirements and concepts shall be prepared for all development applications. The City may exclude building permits for single or two family urban dwellings or developments applications with a total impervious site area less than 500m2 including all structure footprints, parking or landscaping features. All plans shall include the following information:  identify the catchment boundaries and conditions (including size, existing and future land use, imperviousness, surface and subsurface conditions) that originate in or drain through development site  available developable land and proposed lot grading  location of and the development impacts to existing major infrastructure and environmentally sensitive areas  3-tier development drainage conditions  identify any necessary infiltration investigation  requirements for flood control and acceptable extents of flooding  downstream system capacity, erosion and bank stability issues  constraints imposed through regulations  operation and maintenance plan  erosion and sediment control plan City of Maple Ridge Design Criteria Manual SECTION D -DRAINAGE September 2015 Page 28 The type of hydrologic analysis or modeling required to support the concept shall be preapproved by the City and determined by the complexity of the watershed and development under consideration. All stormwater calculations or modeling results will be submitted in support of the rezoning, subdivision or development permits. Where Stormwater Management Plans require works or facilities to control stormwater discharge detailed plans, specifications and an Operation and Maintenance Plan sealed by a Professional Engineer will be required. Each facility will be designed in accordance with most current “Metro Vancouver Source Control Guidelines”. D3 DESIGN FREQUENCIES The following storm return frequencies shall be used for the design of the drainage system: Storm water management Plan Tier A: 50% of MAR* Tier B: 50% of MAR* to MAR* Tier C: Exceed MAR* Conveyance Minor Systems: 1 in 10 years Major Systems: 1 in 100 years *Mean Annual Rainfall (MAR) is considered as the 2 year 24 hour return event. Under special circumstances, drainage facilities in major watercourses may be required to accommodate flows with return frequencies greater than 1 in 100 years. The Designer should confirm the required return frequency with the Municipal Engineer. D4 RUNOFF ANALYSIS Conveyance systems shall be designed to accommodate the post-development flows based upon the ultimate OCP land use. Storage shall use the pre-development flows based upon naturalized land use. All calculations pertinent to the design of the drainage system shall be signed and sealed by the Design Engineer and submitted to the City. The Rational Method shall only be used to compute peak runoffs for developments where the total tributary area is 10 hectares or less. For developments where the total tributary area is greater than 10 hectares the Runoff Hydrograph Method shall be used. For the simulation of large watersheds or complex drainage systems, including those involving multiple detention facilities or infiltration systems, the Municipal Engineer may require the use of extended duration and sequential storms or continuous rainfall data. The owner’s engineer shall obtain the appropriate rainfall data for the analysis. City of Maple Ridge Design Criteria Manual SECTION D -DRAINAGE September 2015 Page 29 D5 RATIONAL METHOD The Rational Method calculates the peak flow using the formula: Q = RAIN Where R = runoff coefficient x soil adjustment factor (SAF) A = drainage area in ha I = rainfall intensity in mm/h N = 0.00278 D5.1 Runoff Coefficients The following runoff coefficients shall be used for the Rational Formula: Land Use Percent Impervious 5/10 Yr Runoff Coefficient 100 Yr Runoff Coefficient Suburban Residential * 20 0.25 -0.35 0.40 Low Density Residential 40 0.30 -0.50 0.55 Medium Density Residential 65 0.40 -0.60 0.65 High Density Residential 78 0.60 -0.75 0.80 Commercial 90 0.70 -0.80 0.85 Industrial 90 0.50 -0.80 0.85 Institutional (i.e. Schools) 80 0.65 -0.75 0.80 Parks/Grasslands 20 0.10 -0.25 0.30 Cultivated Fields 30 0.10 -0.30 0.40 Woodlands/Forested 5 0.05 -0.10 0.30 *Average lot 0.5 ha or greater D5.2 Soil Adjustment Factor A soil adjustment factor (SAF) shall be applied to the runoff coefficient to reflect the local ground conditions. Surface Type SAF Sandy soil with flat slope (up to 5%) 0.9 Sandy soil with steep slope (over 5%) 1.0 Clayey soil with flat slope (up to 5%) 1.0 Clayey soil with steep slope (over 5%) 1.1 The runoff coefficients and soil adjustment factors listed above are for general application. The Designer shall verify that the coefficient is appropriate for the design area. The Municipal Engineer will be the final authority on the coefficient to be utilized. City of Maple Ridge Design Criteria Manual SECTION D -DRAINAGE September 2015 Page 30 D5.3 Catchment Area The tributary area used for the design of the storm drainage shall be consistent with the actual contours of the land and assumed future development boundaries. Although minor changes in the catchment boundaries may be necessary for the development, the total development tributary area should not deviate from the total natural drainage area and assumed future development boundaries as directed by the Municipal Engineer. Some catchment areas will be tributary to more than one storm sewer, and in the absence of definite development proposals for tributary lands, all sewers shall be designed to accommodate the drainage. While contour maps provided by the City are reasonably indicative of the actual conditions, designers are cautioned not to interpret them to be exact and correct. The Designer is responsible for obtaining true and accurate surface elevations for the analysis. D5.4 Time of Concentration The time of concentration is the time required for water to flow from the most remote part of the catchment area under consideration to the design node. For both urban and rural areas, the time of concentration consists of the following formula: Tc = Ti + Tt Where Tc = time of concentration (minutes) Ti = inlet or overland flow time (minutes) Tt = travel time in sewers, ditches, channels or watercourses (minutes) Inlet or Overland Flow Time (Ti) a) Overland Sheet Flow Time in Undeveloped Basins The maximum overland sheet flow distance for undeveloped basins is 300m, but shall be reduced to 250m for basins less than 20 hectares. The minimum overland flow time shall not be less than 15 minutes. b) Typical inlet times for urban areas are as follows: 4000 m2 Lot 15-30 minutes 2000 m2 Lot 15-20 minutes 700 m2 Lot 10-15 minutes Single Family Lot 10 minutes Multi-Family Lot 8 minutes Commercial/Industrial /Institutional 5 minutes c) The inlet time in rural areas shall be calculated using the Airport Method: 3.26 (1.1-C) L0.5 Ti = S0.33 City of Maple Ridge Design Criteria Manual SECTION D -DRAINAGE September 2015 Page 31 Where Ti = inlet time (minutes) C = runoff coefficient L = travel distance (m), maximum length = 300m S = slope of travel path (%) Travel Time (Tt) The travel time in sewers, ditches, channels or watercourses can be estimated using the following formula: Ct L n Where Tt = 12 s0.5 Tt = travel time (minutes) Ct = flow travel coefficient (0.5) L = length of flow (m) n = roughness coefficient 0.050 natural channels 0.030 excavated ditches or packed clay 0.013 asphalt or concrete lined channels 0.013 concrete or PVC pipe s = slope in m/m The above equation provides an approximate travel time, which shall be corrected with the actual time of flow calculated from the hydraulic properties of the selected pipe/channel. A composite value for Tt shall be calculated in cases where the type of flow along the longest path varies or the slope changes. D5.5 Rainfall Intensity Rainfall data from the Metro Vancouver rain station at Golden Ears Elementary School shall be used for rational method calculation in the City of Maple Ridge. Rainfall Intensity-Duration-Frequency (IDF) data for the station is provided on the following pages. The rainfall intensity (I) for the Rational Formula shall be determined from the rainfall IDF curves based on the calculated time of concentration for a given catchment. For catchments above elevation of 150m, as shown in “Kerr Wood Leidal Rainfall Boundaries” below, a multiplication factor of 1.4 shall be applied to the IDF rainfall intensities to account for variation of rainfall with elevation in the City. City of Maple Ridge Design Criteria Manual SECTION D -DRAINAGE September 2015 Page 32 GREATER VANCOUVER SEWERAGE AND DRAINAGE DISTRICT DM62 Golden Ears Elementary School RAINFALL INTENSITY -DURATION FREQUENCY VALUES (ALL DURATION) COMPUTED FROM THE INTERPOLATION EQUATION -INTENSITIES (mm/hr) DURATION RETURN PERIOD 2 year 5 year 10 year 25 year 50 year 100 year 5 min 47.66 68.37 82.05 99.31 112.10 124.79 15 min 27.98 40.13 48.16 58.28 65.78 73.22 30 min 19.99 28.68 34.41 41.63 46.99 52.30 1 h 14.29 20.49 24.58 29.74 33.57 37.36 2 h 10.21 14.64 17.56 21.25 23.98 26.69 6 h 5.99 8.59 10.31 12.47 14.07 15.66 12 h 4.28 6.14 7.37 8.91 10.05 11.19 24 h 3.06 4.39 5.26 6.36 7.18 7.99 48 h 2.19 3.14 3.76 4.55 5.13 5.71 72 h 1.80 2.58 3.09 3.73 4.21 4.69 City of Maple Ridge Design Criteria Manual SECTION D -DRAINAGE September 2015 Page 33 RAINFALL IDF CURVE – ALL DURATION-DM62 GOLDEN EARS ELEMENTARY City of Maple Ridge Design Criteria Manual SECTION D -DRAINAGE September 2015 Page 34 City of Maple Ridge Design Criteria Manual SECTION D -DRAINAGE September 2015 Page 35 D6 RUNOFF HYDROGRAPH METHOD D6.1 Selection of Modeling Program For basins larger than 10 hectares, hydrologic programs shall be used for runoff analyses. Standard runoff simulations shall be modelled with the OTTHYMO.89 program. The EPA-Stormwater Management Model (SWMM), the Illinois Urban Drainage Area Simulator (ILLUDAS) and other hydrologic programs may be considered if their uses are deemed necessary and approved by the Municipal Engineer. D6.2 Design Rainfall Rainfall Intensity Reduction for Areal Effects Percentage reductions in average rainfall intensities which have recurrence intervals of 2 to 100 years and durations of ½ to 24 hours are proportional to the size of the basin but their use shall be limited to basins equal to or larger than 26 km2 (6,425 acres) only. Elevation Multiplication factors for IDF Curves and Design Storms For watersheds above elevation of 150m, as shown in Section 5.5 a factor of 1.4 shall be applied to the IDF Rainfall Intensities and design storm incremental rainfall depths to account for variation of rainfall intensities due to elevation. Section D5.5 provides the intensity-duration-frequency curve from the Metro Vancouver rainfall station at Golden Ears Elementary School that shall be used for rational method calculations at the City of Maple Ridge. Design Hyetograph Design storms that reflect historic conditions within the City of Maple Ridge will be used for Hydrograph Method computations. IDF data from three Metro Vancouver rain gauges, Maple Ridge Reservoir, Katzie Pump Station and Golden Ears Elementary School, and one AES rain gauge, Haney UBC Research Forest (Haney UBC RF ADMIN), were used to develop design storm hyetographs. As shown in D5.5, each of the four gauges is assigned to a specific catchment area within the City to account for variation in rainfall distribution throughout the City. Design storm hyetographs for areas covered by the Maple Ridge Reservoir, Haney UBC Research Forest, Katzie Pump Station and Golden Ears Elementary School as delineated in D5.5 for durations of 30 minute, 1 hour, 2 hour, 6 hour, 12 hour and 24 hour are available from the City in digital form. Longer duration rainstorms which are typical for the Lower Mainland last about three to five days. These events are critical for the effective functioning of stormwater storage facilities. For example, in March of 2007, two events were recorded at the Maple Ridge Reservoir rain station with a total rainfall depth of 144mm and 147mm, and had return frequencies of approximately 2 to 5-year. These rainfall events are summarized below. These events shall be used for demonstrating storage facilities design performance during such events. City of Maple Ridge Design Criteria Manual SECTION D -DRAINAGE September 2015 Page 36 Three Day Storm Events (Un-factored for Elevation) Storm Event Return Period Total Rainfall (mm) March 8, 2007 15:00 to March 11, 2007 18:00 2-year to 5-year 144 March 21, 2007 22:00 to March 24, 2007 22:00 2-year to 5-year 147 Long duration wet-weather periods of up to one month containing 5 to 100 year level storms are critical to the adequate functioning of storage facilities. All proposed stormwater control facilities must be tested at the design stage to confirm their safe operation for these critical wet weather periods. Using the historical hourly rainfall data for the Maple Ridge Reservoir rain station, appropriate critical periods have been selected and are tabulated below. The related hourly data for long duration performance analysis is available from the City in digital form. Maple Ridge Selected 30-Day Rainfall Totals (Un-factored for Elevation) Storm Event Return Period Total Rainfall (mm) September 4, 1996 Up to a 100-Year (including 5, 10, 25, and 50-year) 189 October 15, 2003 Up to a 50-Year (including 5, 10, and 25-year) 382 September 16, 2004 Up to 25-Year (including 5,and 10-year) 123 D6.3 Watershed Data Watershed data includes catchment areas, percent of imperviousness, lengths of flow, surface slopes, soil types (CN value), etc. The tributary area used for the design of the storm drainage system shall be consistent with the actual contours of the land and expected development boundaries. Although minor changes in the catchment boundaries may be necessary for development, the total developed tributary area should not deviate from the total natural drainage area and expected development boundaries. While contour maps available from the City are reasonably indicative of the actual conditions, designers are cautioned not to interpret them to be exact and correct. The Designer is responsible for obtaining true and accurate surface elevations for the analysis. The imperviousness of common land uses are tabulated in D5.1 and D5.2. For design purposes, the drainage model shall be based on the post-development conditions using the most current planning information. Conservative parameters shall be selected if calibration data is not available. City of Maple Ridge Design Criteria Manual SECTION D -DRAINAGE September 2015 Page 37 For assessment of existing systems, the drainage model may be based on the existing conditions if no future land use changes are anticipated. Some parameters may be adjusted in order to calibrate the drainage model. D6.4 Presentation of Modeling Results The Designer will be required to submit a drainage report including the following:  name and version of modeling program  design storms and default parameters  schematic diagram of the model  drainage map showing the catchment and sub-catchment boundaries, slopes, land uses, soil conditions, etc.  input and output printouts and computer files D7 STORMWATER STORAGE FACILITIES Storage facilities shall be designed according to requirements of either the Master Drainage Plan or Integrated Watershed Master Plan if available, in consideration of the minor and major systems. The construction of a community storage facility servicing a large catchment area is preferred over small ponds servicing localized areas. The common storage facilities are: Detention (Dry) Storage  Retention (Wet) Storage  On-site Storage The Designer shall consider the site and downstream conditions and consult the Engineering Department to determine the most suitable type of storage facility. D7.1 Release Rates Peak flow and runoff volume shall be controlled for both major and minor storms to protect downstream properties, infrastructure, natural streams and other resources. Controls to prevent erosive flows in watercourses shall recognize both peak flow rates and the duration of peak flows. The objective is to limit both the magnitude and the duration of post-development peak flows up to the 1:100 design storms to that of the pre-development peak flows as far as possible. In the absence of detailed review of downstream watersheds, specific requirements or other measures developed in watershed studies and/or agreements with other jurisdictions approved by Council, the following additional criteria shall be used:  For mitigation of environmental concerns limit the post-development peak rate of runoff from the development site from the two-year design storm to 50 percent of the natural peak runoff flow from the two year design storm.  Downstream detrimental impacts shall not be increased, or the provisions for downstream improvements must be provided. City of Maple Ridge Design Criteria Manual SECTION D -DRAINAGE September 2015 Page 38  Increases in peak storm flows and volumes to major watercourses, drainage systems and receiving waters shall be minimized. Consideration shall be given to fish bearing streams, streams or drainage systems presently at capacity. Limits on major flood routes will be required up to the 1:100-year storm;  Groundwater infiltration is to be encouraged only where the watershed studies or City policy determine that this practice is appropriate. Allowance shall not be made for infiltration in hydraulic design of the major route. D7.2 Design Volume (Small Catchments) For small catchments (10 ha or less), the design storage volume is to be calculated using the Modified Rational Method Analysis. The Modified Rational Method Analysis creates a number of symmetrical triangular and trapezoidal hydrographs for storms of different durations using the rational formula Q=RAIN where I is the average rainfall intensity for the specified storm duration (Tr). The peak discharge coincides with the time of concentration (Tc) from the most distant point of the basin. The time of the rising limb and the time of the falling limb of each hydrograph are both equal to Tc. The area below the triangular or trapezoidal hydrograph is the volume runoff. After the maximum release rate (i.e. pre-development flow) is selected, an outflow hydrograph is determined to compute the storage volume. For simple outlet controls, the outflow hydrograph can be approximated by assuming that it will increase linearly and reach the maximum release rate where it intersects the receding limb of the inflow hydrograph where the storm duration is equaled to the time of concentration of the basin (see Figure D5). The release rate is assumed to remain at the maximum rate thereafter. For more complex outlet controls, a reservoir routing procedure as documented in standard engineering manuals is required. The required storage is represented by the area between the inflow hydrograph and the outflow hydrograph (Figure D5). The storage volume (m3) can be calculated by: 1 1 Storage Volume = Tr ( Qp2-Qrel ) + 0.5 Tc Qrel 2 ( ) Qp2 Qp1 Where Tr = duration of specified storm (seconds) Tc = time of concentration (seconds) Qp1 = peak flow for storm duration Tr = Tc (m3/s) Qp2 = peak flow for specified storm duration (m3/s) Qrel = maximum release rate (m3/s) Storms with durations greater than the normal time of concentration (Tr > Tc) will result in peak flow rates less than storms where Tr = Tc but may produce more runoff volume. Therefore several storms with varying durations must be City of Maple Ridge Design Criteria Manual SECTION D -DRAINAGE September 2015 Page 39 analyzed to determine the critical design volume. Figure D6 shows an illustrative example of a storage volume calculation using the Modified Rational Method. City of Maple Ridge Design Criteria Manual SECTION D -DRAINAGE September 2015 Page 40 City of Maple Ridge Design Criteria Manual SECTION D -DRAINAGE September 2015 Page 41 City of Maple Ridge Design Criteria Manual SECTION D -DRAINAGE September 2015 Page 42 D7.3 Design Volume (Large Catchments) For large catchment areas over 10 ha in size, storage requirement shall be computed by the OTTHYMO-89 program. Once the allowable release rate is established, the designer shall run the model for storms of various durations and selected the critical storage requirement. D7.4 Outlet Control The outlet control for storage facilities may be designed using the standard orifice and weir equations: Orifice Equation: Q = C A (2 g h)0.5 Where Q = release rate (m3/s) C = orifice coefficient (0.62 for sharp or square edge) A = area of orifice (m2) g = gravitational acceleration (9.81m/s2) h = net head on orifice (m) Weir Equation: Q = C L H 1.5 Where Q = release rate (m3/s) C = weir coefficient (from published references) L = effective length of weir crest (m) H = net head on weir crest (m) Large storage facilities shall include provisions for discharging water above the design release rate. The rapid drawdown of the facility may be necessary for emergency purposes or to restore the available storage to accommodate subsequent storm events. The provisions to accommodate higher discharges will involve oversizing the fixed openings and sewers connected to control structure. Adjustable mechanisms such as slide gates or removable orifice plates can be used to regulate the design release rates. The extent of the oversizing will depend on the capacity of the downstream drainage system. The design of inlet/outlet structures shall consider flow energy dissipation and erosion control. Safety grates are required over all inlet/outlet openings equal to or larger than 525mm in diameter. Locks for access hatches are required to prevent unauthorized entrance to the structure. D7.5 Emergency Overflow An emergency overflow spillway with capacity to convey the 1:100-year flow and larger is required for all storage facilities. The spillway surface shall be finished with erosion resistant materials such as concrete, turf stone or other approved equal. The maximum spillway slope is 4 (horizontal) to 1 (vertical). The design of the spillway City of Maple Ridge Design Criteria Manual SECTION D -DRAINAGE September 2015 Page 43 and/or overflow shall consider the possibility of blockages in the outlet structure and the consequences of extreme storm events. D7.6 Operation and Maintenance Requirements A minimum 3m wide all-weather vehicle access shall be constructed from a public road right-of-way to the control outlet and other works requiring maintenance. The maximum grade of the access is 15%. The surface shall be finished with asphalt, gravel, concrete, or turf stones suitable for maintenance traffic as required by the City. A sediment sump accessible to maintenance equipment shall be provided near the pond inlet. For large detention facilities (over 2,000m3 of storage); the Designer shall submit six copies of the operation and maintenance manual at the time when the facility is completed and transferred to the City. The manual shall include:  Record Drawings of the completed facility.  brief description of the facility operation including design flows, design depths and schematic diagrams of the inlet and outlet structures, connections, controls, valves, bypass, overflows, etc.  list of manufacturer’s operation, service and repair instructions and part lists.  volume-stage discharge relationships of all control structures.  general maintenance requirements and emergency procedures.  copies of approval from senior government agencies (if applicable).  approved planting plan and long term maintenance tasks. D7.7 Safety Barrier and Signage Storage facilities shall have proper warning signage and chain link fence all around. D7.8 Detention (Dry) Storage One of the most common forms of runoff control is detention (dry) storage. A detention pond is normally “dry” and only retains water during severe storm events. A control outlet permits the low flow to discharge downstream but limits the higher flows exiting into the downstream system. The excess runoff is temporarily stored in the detention pond and gradually release back into the drainage system. A detention pond can be constructed on-line or off-line from the drainage path, depending on the site conditions and the environmental constraints. The design standards are as follows: maximum depth of storage (up to 1:10 Year) 1.5m maximum depth of storage (over 1:10 Year) 2.5m minimum bottom slope 0.7% maximum pond side slopes 4(H):1(V) preferred side slope 7(H):1(V) City of Maple Ridge Design Criteria Manual SECTION D -DRAINAGE September 2015 Page 44 The berm of the pond shall be constructed of stable impermeable material such as clay, compacted glacial till or an impermeable geo-membrane with permeability coefficient in the order of 1 x 10-8m/s. A landscaping plan detailing the reinstatement of grass cover or other approved surface finish is required for all dry detention ponds. D7.9 Retention (Wet) Storage Retention storage provides temporary detention of severe storm runoff while holding runoff from the frequent rain events in a pool of water throughout the year. A control outlet regulates the amount of flow released into the downstream system. During a storm event, the retained water is partially or completely replaced with stormwater. The design criteria is as follows: minimum land requirement (% of total catchment area) 0.5% to 2% recommended minimum length to width ratio 2:1 minimum pond depth (normal water level) 1.0m maximum pond depth (high water lever) 3.0m maximum side slopes from pond bottom to low water level 4(H):1(V) maximum side slopes from low water to high water level 7(H):1(V) maximum side slope above high water level 4(H):1(V) minimum freeboard above high water level 0.5m A retention pond requires a continuous base flow to maintain the permanent pool. A complete water budget analysis under post-development conditions is required to ensure that the base flow will exceed evaporation and seepage losses. Considerations shall be given for the circulation of water while narrow and/or dead bay areas are to be avoided. Provisions for draining the lake completely by gravity should be included if possible. Otherwise, provisions for a mobile pumping unit shall be included. A forebay shall be provided at the pond inlet for sedimentation control. The pond berm shall be constructed of stable impermeable material such as clay, compacted glacial till or impermeable geo-membrane with permeability coefficient in the order of 1 x 10-8 m/s. A landscaping plan detailing the reinstatement of grass cover or other approved surface finishes on the side slopes and the surrounding berm is required. Special plant species may be required for environmental enhancement. D7.10 On-Site Detention Storage On-site detention may consist of a number of methods such as parking lot storage, exfiltration trenches/drywells, rock pits, etc. Some common on-site storage methods are outlined below: Parking Lot Storage  requires detailed lot grading design to ensure proper drainage City of Maple Ridge Design Criteria Manual SECTION D -DRAINAGE September 2015 Page 45  ponding shall be located in the remotest areas of the parking lot or along grass medians  maximum ponding depth is 100mm for 1:2 year storm, 150mm for 1:5 year storm and 300mm for 1:100 year storm  emergency overflows are required for events exceeding the design frequency  release rate shall be regulated by a standard flow control manhole Exfiltration Trenches and Drywells  only permitted where the native soils demonstrate high permeability and groundwater table is well below the invert of the trench (geotechnical investigation required)  capacity of the system shall be determined from site-specific data  a positive drainage outlet is required  the 1:10 year hydraulic grade line shall be below all service connections at the property lines  the 1:100 year hydraulic grade line shall be at least 0.35 m below adjacent MBE’s  sediment traps are required at or before inlet to trenches  drywell (perforated) manholes shall be used in place of standard manholes  shall be located in greenways, parks and open spaces wherever possible  emergency overflows are required for storm events exceeding the design frequency  release rate shall be regulated by a standard flow control chamber Other Storage Systems Due to a variety of site-specific characteristics, it is not possible to list all the unique or typical storage alternatives. Designers shall review all proposals for onsite detention systems with the Engineering Department prior to detailed design. On-site detention for a single detached family lot and roof top storage are not permitted. D8 STORM SEWERS AND APPURTENANCES D8.1 Sizing of Storm Sewers The required storm sewer capacity shall be calculated using the Manning Formula under free flow (non-surcharged) condition. The Manning formula is: A R0.667 S0.5 Q = n Where Q = flow capacity (m3/s) A = cross sectional area (m2) R = hydraulic radius (m) City of Maple Ridge Design Criteria Manual SECTION D -DRAINAGE September 2015 Page 46 S = slope of hydraulic grade line (m/m) n = roughness coefficient 0.011 for PVC pipe 0.013 for asbestos cement, clay and concrete pipe 0.024 for corrugated metal pipe (CMP) 0.020 for paved invert CMP NOTE: Asbestos cement pipes, clay pipes and corrugated pipes are not acceptable for new storm sewers. Downsizing of storm sewers will not be accepted for sizes 600mm diameter or less. A maximum downsizing of two pipe sizes for storm sewers larger than 600mm diameter will be considered. The minimum size of storm sewers shall be 250mm diameter. For the purpose of reference in this section, large diameter sewer refers to sizes 675mm or larger, and small diameter sewer refers to sizes 600mm and smaller. D8.2 Minimum/Maximum Velocity The minimum velocity for pipes flowing full or half full shall be 0.75m/s. There is no limit on the maximum velocity. However, if the design velocity exceeds 3.00m/s and/or supercritical flow occurs, provisions for structural stability and durability of the pipe shall be included. Anchor blocks are required where the pipe grade is steeper than 15%. Where drainage discharge enters a natural watercourse, senior government agencies generally require adequate rip rap protection and limits the maximum velocity to 1 m/s. D8.3 Minimum Depth of Cover The minimum depth of cover shall be 1.0m and sufficient to allow gravity connections from 0.6m below the existing or proposed basement elevation and potentially a 2% grade to the crown of the pipe for vacant lands. For pipe sizes larger than 600mm or for cover less than that specified above, an engineering design for cover will be required. The depth of storm sewers shall be adequate to service all adjacent developments as well as all existing properties within practical limits. The invert of storm sewers at the upstream end must be of sufficient depth to service all of the tributary lands. In common trench installations, the sanitary service connections shall be permitted to cross over top of the storm sewer. D8.4 Pipe Joints All storm sewer systems shall be designed for open joint except where the pipe is designed to act under head or to be a through pipe or prevent bedding migration. City of Maple Ridge Design Criteria Manual SECTION D -DRAINAGE September 2015 Page 47 D8.5 Curvilinear Sewers Where curvilinear sewers are proposed, the minimum radius should not be less than 60m and only where the maximum joint deflection is one half of the pipe manufacturers’ recommendations. Minimum grades shall be 59 percent greater than calculations for straight sections. Video inspections are required for curvilinear sewers as directed by the Municipal Engineer. D8.6 Sewer Location Storm sewers shall be designed within the road right-of-way using the offsets as shown on the applicable road cross-section standard drawing. Sewers and manholes should be offset from the vehicular wheel paths wherever possible to minimize the roughness of travel. Where the storm sewer is required to cross private lands, the right-of-way shall have a minimum width of 3m. Where both storm and sanitary sewers are located within a single right-of-way, the minimum width shall be 4.5m. For pipes that exceed 3.0m additional width will be required. When a storm sewer and other appurtenances (i.e. manholes, gate chambers, etc.) are located within a right-of-way, the Developer may, for maintenance purposes, be required to provide vehicular access from an existing municipal road. The maintenance access shall be constructed to City standards adequate to support the maintenance vehicles for which the access is intended. Where an access is required, the access is to be located entirely on one lot. D8.7 Utility Separations Refer to Section W – Water, W10 Clearance With Sewer Pipes for clearance with watermains. For clearances with other utilities such as Fortis BC, Telus, BC Hydro, cable, etc., consult the respective authorities. D8.8 Manholes – Standard Requirements Manholes are required at:  every planned or existing intersecting sewer  all changes in pipe size  every 120m for pipes less than 900mm diameter  every 200m for pipes 900mm diameter and larger  all changes in direction that exceeds ½ of the maximum joint deflection recommended by the pipe manufacturer  downstream end of curvilinear sewers City of Maple Ridge Design Criteria Manual SECTION D -DRAINAGE September 2015 Page 48 Common design requirements are: a) The crown of pipes entering a manhole shall be set at or above the crown of the outlet pipe and the springline of the downstream pipe shall not be higher than that of the upstream pipe in any case. b) Outside drop connections shall be provided wherever the drop exceeds 0.60m and avoid drops between 0.25 ~ 0.60m. For incoming pipes 600mm and larger in diameter, special drop design will be required. c) Sudden and extreme changes in direction for large sewers should be avoided. d) For sewers 675mm and larger with 90 degree directional change, the ratio of the radius of bend (measured to the pipe centreline) to the pipe inside diameter should be greater than 2. Otherwise, the maximum bend deflection at one point shall be 45 degree (i.e. use two 45 degree bends to turn 90 degrees). e) 90 degree bends in sewers 675mm and larger shall not be located inside a junction with other sewer connections. Separate manholes are required. f) To minimize the head loss in sewers 675mm and larger, high incoming flows from the opposite direction should not impinge in the same manhole structure. Separate manholes are to be used. g) Manhole anchorage may be required for 90 degree bends with large flows or high velocity flows. h) Capped stubs shall be provided with the grade, size and location suitable for future extension. D8.9 Manholes – Hydraulic Losses Invert drops across manholes are required to compensate for the hydraulic (energy) losses due to changes in flow directions. The required drop in invert levels is the hydraulic loss across the manhole. For junctions involving large diameter sewers or high velocity flows, detailed engineering analyses may be required. For small diameter sewers (600mm or smaller) and low velocity flows, the following equation can be used to calculate the head loss: V2 HL = k 2g Where HL = head loss (m) k = head loss coefficient (see next 2-pages) V = outlet flow velocity (m/s) g = gravitational acceleration (9.81m/s2) City of Maple Ridge Design Criteria Manual SECTION D -DRAINAGE September 2015 Page 49 The minimum drops are:  straight run no drop required  deflections up to 45 degree 30mm drop  deflection 45 degree to 90 degree 60mm drop City of Maple Ridge Design Criteria Manual SECTION D -DRAINAGE September 2015 Page 50 City of Maple Ridge Design Criteria Manual SECTION D -DRAINAGE September 2015 Page 51 City of Maple Ridge Design Criteria Manual SECTION D -DRAINAGE September 2015 Page 52 D8.10 Catch Basins Catch basins shall be provided at regular intervals along roadways, at upstream end of radius at intersections and at low points (sags). Low points are not to be located within curb returns at intersections and shall provide side-inlet catch basins along barrier curbs or double catch basin along rollover curbs. The Designer must ensure sufficient inlet capacity is available to collect the entire minor flow into the underground pipe system. The maximum spacing shall be established to permit each catch basin to drain an area of 500m2 on road grades up to 4% and 350m2 on steeper grades. If the major flow is to be conveyed in the pipe system, additional catch basins may be required. The spacing of catch basins shall be based on hydraulic requirements. The capacity of a single catch basin can be calculated by the orifice equation: Q = 0.67 C A (2 g h ) 0.5 Where Q = inlet capacity (m3/s) 0.67 = clogging factor C = orifice coefficient (0.8) A = open area (0.068m2 for Dobney B-23 grate) g = gravitational acceleration (9.81m/s2) h = depth of ponding (m) The minimum size for catch basin leads is 200mm for single catch basins and sideinlet catch basins. Catch basin leads should be taken directly into manholes if feasible. The minimum grade for leads is 1.0%. The maximum length is 20m. D8.11 Lawn Basins Lawn basins shall be provided as per the requirements listed in the D2.5 Stormwater Management Plan. Lawn basin leads shall have a minimum size of 150mm and a minimum slope of 1%. D8.12 Temporary Clean-Outs Temporary clean-outs may be provided at terminal sections of a main provided that all the following conditions are met:  future extension of the main is proposed or anticipated  the length of sewer to the downstream manhole does not exceed 45m  the depth of the pipe does not exceed 2m at the terminal point NOTE: Clean-outs can not be considered permanent structures. City of Maple Ridge Design Criteria Manual SECTION D -DRAINAGE September 2015 Page 53 D8.13 Service Connections Service connections shall be installed to provide a “gravity-flow” connection to all buildings fronting the main, except where the land can drain to an acceptable alternate existing system. The design requirements are: a) The minimum diameters are 150mm for residential and 200mm for industrial/commercial. Pipe shall be PVC type PSM DR 28 with a minimum stiffness of 65Kpa and manufactured to ASTM D3034 and certified by CSA B182.2. b) The minimum slope from the main to the property line shall be 2% for 150mm and 1.5% for 200mm. All other sizes shall be based on minimum velocity of 0.75 m/s. c) The connection shall be located at the lower (downstream) portion of a larger lot or land parcel. In urban developments, connections shall be as noted on the applicable standard drawing. The curb face directly above the service shall be marked with a “ST” d) The service connection at the property line shall be above the hydraulic grade line of the minor flow. e) Each connection shall only service one single lot, but upon demonstrated need and approval from the Municipal Engineer, more than one service may be granted. f) When the design proposes to infill an existing ditch, all existing service connections are to be connected to the proposed main. g) A manhole shall be required on all service connections where the size of the connection is greater than 200mm in diameter, unless the connection is more than two pipe sizes smaller than the main to which it is joining. A service connection exceeding 20m in length will be treated as a regular main. h) Inspection chambers are required on residential connections unless the service is less than 2.5m long and connects to a manhole. i) Unless otherwise authorized by the City, foundation perimeter drains shall be connected by gravity to the storm sewer system, provided that the elevation of the basement floor is at least 600mm above the elevation of the building service connection at property line or 150mm above the major hydraulic gradeline at that point, whichever is higher. D8.14 French Drains The use of French drains shall only be permitted where the topography and soil conditions are proven adequate to the acceptance of the Municipal Engineer. A soils report will be required to support the design. City of Maple Ridge Design Criteria Manual SECTION D -DRAINAGE September 2015 Page 54 D8.15 Rock Pits The practice of using rock pits for drainage is discouraged and will only be permitted at the discretion of the Municipal Engineer. Rock pits for drainage will only be considered in certain areas of the city where it can be demonstrated that the subsoil conditions will provide a percolation rate equal to, or in excess of, twice the minor runoff flows. A soils report will be required to confirm the suitability of the soils. This does not preclude the requirement for minor flood path routing and all designs shall incorporate a positive outlet for rainfall intensities in excess of the minor system design. D9 MAJOR FLOW ROUTING AND FLOOD CONTROL D9.1 Major Flow Routing Unless the storm sewer system is oversized to accommodate the major flow (i.e. 1:100-year return frequency storm), provision for surface flow is required wherever the overland flow in excess of 0.05m3/s is anticipated. Major flow routing is generally accommodated along roadways, swales and watercourses. These designated flow paths shall be protected by restrictive covenants or right-of-ways and clearly identified in the stormwater management plan. The quantity of flow to be conveyed by the surface flow path is the total major flow less the capacity of the minor system. The design of the major flow routing shall ensure to the satisfaction of the Municipal Engineer that no endangering of public safety or substantial property damages will occur under the major flow conditions. D9.2 Roadway Surface Drainage Roadways with barrier curbs and gutters can be designed as wide shallow channels to convey major surface flow. The required freeboard between the water elevation at maximum ponding/flow and the lowest minimum building elevation of the adjacent buildings is specified in D9.8. The maximum depths of flow shall not exceed 150mm above the gutter line. Flow velocity greater than 2.5m/s must be approved by the Municipal Engineer. Refer to Table D10 for calculating the flow capacities for various road grades. The Design Engineer shall consider the impact of surface routing on the major flow hydraulic grade line (HGL) of adjacent lateral roads. Existing lateral roads designed with the major HGL below surface may preclude using surface flow routing on the road under design. Routing of major surface flow on roads with rollover curbs is discouraged. The Design Engineer shall submit calculations to verify that the surface flow is maintained within the road right-of-way, leaving a 3.5m lane with no flooding, and the water elevation at maximum ponding/flow is at least 0.6m below the lowest Minimum Building Elevations (MBE) of adjacent buildings. City of Maple Ridge Design Criteria Manual SECTION D -DRAINAGE September 2015 Page 55 The design of intersections shall ensure that the surface flow can continue along the designated path crossing over lateral streets. Similar considerations are required if a change of surface flow direction is required at an intersection. City of Maple Ridge Design Criteria Manual SECTION D -DRAINAGE September 2015 Page 56 City of Maple Ridge Design Criteria Manual SECTION D -DRAINAGE September 2015 Page 57 D9.3 Ditches Ditches are not acceptable for permanent servicing of land development projects within the urban area. They may be considered only for special interim uses. Ditches adjacent to roadways shall conform to the following criteria: a) maximum depth 1.0m b) minimum bottom width 0.5m c) maximum side slope 1.5(H):1(V) d) minimum grade 0.5% e) maximum velocity (Unlined ditch) 1.0m/s Where soil conditions are suitable or where erosion protection is provided, higher velocities may be permitted. If grades are excessive, erosion control structures or ditch enclosure may be required. The minimum right-of-way width for a ditch shall be 5m where the ditch crosses private property. The ditch shall be offset in the right-of-way to permit a 3m wide access for maintenance vehicles. Additional rights-of-way may be required to facilitate the ditch construction and access. The top of the ditch adjacent to the property line shall be a minimum 0.5m away from that property line. D9.4 Watercourses Natural watercourses are integral components of the major drainage system and the ecological system. If the process of development or drainage design involves instream works, the Designer shall refer to the "Land Development Guidelines for the Protection of Aquatic Habitat" by Department of Fisheries and Oceans Canada and BC Ministry of Water Land and Air Protection. All proposals for works affecting natural watercourses must be forwarded (by the Designer) to the applicable Federal and Provincial Government agencies for review. D9.5 Culverts and Bridges Culverts located in natural watercourses or culverts crossing all roads shall be designed to convey the major flow or greater. The Designer shall determine whether the culvert will operate under inlet or outlet control at design conditions. Concrete culverts are preferred for general uses. Corrugated steel culverts may be considered under special circumstances when their use can be justified. The minimum diameter of culverts is 450mm (300mm for driveway culverts). The average water velocity in culverts should not exceed:  1.2m/s for lengths up to 24.4m  0.9m/s for lengths over 24.4m City of Maple Ridge Design Criteria Manual SECTION D -DRAINAGE September 2015 Page 58  for culverts longer than 61m within a fishery stream, special conditions from DFO and MOWL and AP will apply The minimum depth of cover for culvert is 0.3m, subject to the correct pipe loading criteria. Inlet and outlet structures are required for all culverts designed for the major flow. Considerations for the installation of energy dissipation and erosion control shall be included in the design. Driveway culverts that form part of the minor system shall have capacity for the runoff from the 1:25-year storm for urban areas and 1:10 or 1:5-year storm for rural areas with the design headwater not to exceed the top of the culvert. All new driveway culverts shall be sized to ensure that there is no adverse impact on adjacent properties under the 1:100-year runoff conditions. Culverts and channels under bridges for arterial and collector roads are to be designed to clear the 1 to 200-year flood level plus 0.6m freeboard. D9.6 Inlet and Outlet Structures Pipes larger than 1200mm in diameter and non-circular culverts require specially designed inlet and outlet structures, and by Municipal Engineer’s approval, pre-cast, pre-fabricated or cast-in-place inlet and outlet structures can be used for pipes up to 1200mm in diameter. Concrete block headwalls as shown on the applicable standard drawing may be used for culverts up to 750mm diameter without design. Outlets having discharge velocities in excess of 1m/s require rip rap protection and/or energy dissipating structures for erosion control. Grills are required at the inlets and outlets of all pipe over 450mm in diameter, which exceed 30m in length (except large culverts in major watercourses). Trash racks are required at the inlet of the pipes utilizing the grills. Grills may also be required on smaller diameter storm sewers at the discretion of the Municipal Engineer. D9.7 Site and Lot Grading Developments shall incorporate site and lot grading techniques. Unless otherwise noted, rural developments with lots 0.405 ha and over will not require Stormwater Management Plans outlining the site and lot grading. The following criteria shall be used: a) Each lot must be graded to drain into a municipal drainage system or a natural drainage path independent of adjacent lots and minimum lot grades shall be 1%. b) Areas around buildings (or proposed building sites) shall be graded away from the (proposed) foundations to prevent flooding. City of Maple Ridge Design Criteria Manual SECTION D -DRAINAGE September 2015 Page 59 c) For lots lower than adjacent roadways, acceptable storm water management techniques must be incorporated to direct the runoff to an existing or proposed drainage system. Proper flood proofing is required at the low points of roadways. d) Existing or proposed buildings must be sited above the hydraulic grade line of the major system. The Designer shall note any existing minimum building elevations (MBE). e) Individual lots will not be permitted to direct storm runoff into any natural watercourse, park or green belt areas. Only sheet flow may be permitted. f) A lawn basin or drain to be placed at the end of every Developer’s swale. g) A builder’s swale in the front yard does not require a lawn basin to be installed prior to discharging onto the roadway. When deposit or removal of soil is required in order to comply with the lot grading plan, the Developer is exempted from the requirements of the Soil Removal/Deposit Bylaw. NOTE: The Developer is advised that lot grading is considered an “essential service” and is required prior to the issuance of building permits. To facilitate building permit issuance, and to provide the builders with accurate site information, the submission and acceptance of the lot grading Record Drawings is required. D9.8 Minimum Building Elevations (MBE) The MBE is defined as the elevation of 0.1m above the lowest floor slab in a building or the underside of the floor joists where the lowest floor is constructed over a crawlspace. Crawlspace is a space between a floor and the underlying ground having a maximum height of 1.2m to the underside of the joints and not used for the storage of goods or equipment damageable by floodwater. The MBE shall be established at least 0.6m above the service connection invert at property line and 0.35m above the 100-year in the uplands and 200-year in the lowlands hydraulic grade line elevation. In areas where the Designer can prove that the 1:100-year runoff is confined within the roadway and isolated from the adjacent properties (i.e. no flow via driveway letdowns or storm connections into adjacent properties), the freeboard between the MBEs and the 1:100-year hydraulic grade line may be reduced to 0.2m. Accepted MBEs may not be revised without referral to the Municipal Engineer. Unless otherwise required, rural and agricultural developments do not require MBEs for the proposed lots/parcels. City of Maple Ridge Design Criteria Manual SECTION D -DRAINAGE September 2015 Page 60 A gravity connection to the municipal storm drainage system may be made only where the habitable portion of a dwelling is above the major system hydraulic grade line. D9.9 Roof Drainage Roof drainage is to be discharged into the municipal drainage system, with the size of the proposed or existing storm sewer being designed for, or can be shown to accommodate the anticipated flows. Where a municipal drainage system is not available a dry well may be used in accordance the BC Building Code and municipal regulations. D9.10 Swales Swales shall be a maximum 150mm deep and all swales are to be lined with turf on a minimum 100mm of topsoil. Swales shall have a minimum 1% grade. D9.11 Siltation Controls Designers are required to demonstrate how work will be undertaken and completed so as to prevent the release of silt, raw concrete, concrete leachate and other deleterious substances into any ditch, storm sewer, watercourse or ravine. Construction materials, excavation wastes, overburden soils, or other deleterious substances shall be disposed of or placed in such a manner as to prevent their entry into any watercourse, ravine, storm sewer system, or restrictive covenant area. Designers must provide a Sediment Control Plan as noted in the current Maple Ridge Watercourse Protection Bylaw. The Designer shall refer to the "Land Development Guidelines for the Protection of Aquatic Habitat" by Department of fisheries and the Ministry of Environment, Lands and Parks and the Watercourse Protection Bylaw. Details of the proposed controls are to be included in the design drawings and shall be the first constructed part of the works. All siltation control devices shall be situated to provide ready access for cleaning and maintenance. Proposed siltation control structures must be maintained throughout the course of construction and to the end of the maintenance period (final acceptance) or until 90% of the lots have been built on, whichever occurs later. Changes in the design of the structure will be required if the proposed structure is found to be inadequate. D9.12 Oil and Grit Separators  Required for sites with parking for 50 or more vehicles.  May be swirl concentrator or equivalent, including proprietary systems such as Stormceptor and Vortechs.  Design details to be provided by supplier of proprietary system or by Designer of equivalent.  Generally located on-site. City of Maple Ridge Design Criteria Manual SECTION D -DRAINAGE September 2015 Page 61 D9.13 Oil/Water Separators  Required for gas stations, vehicle service areas and storage areas for highway vehicles and construction equipment.  Coalescing plate separator required.  Design details in accordance with current technologies as outlined in Urban Runoff Quality Control Guidelines for British Columbia, and related documents. D10 ACCEPTED PRODUCTS Inspection Chambers Le-Ron Plastics 100 x 200 7A 4-WOD or equivalent chamber 150 x 200 70A6W/OP Green 200-70A LID 086 lid Green 200-73A 08-H5 collar Terminal City Cast iron cover 250 diameter stamped with appropriate utility identification, complete with locking bolts (required in driveway only) City of Maple Ridge Design Criteria Manual SECTION D -DRAINAGE September 2015 Page 62 THIS PAGE INTENTIALLY LEFT BLANK City of Maple Ridge Design Criteria Manual September 2015 Page 63 SECTION S -SANITARY SEWER S1 SYSTEM CAPACITY The Designer shall discuss downstream system capacity requirements with the Municipal Engineer. If required, adequacy of the existing system, downstream of the proposed catchment area, shall be done using the analytical methods given in the following sections. S2 METHODOLOGY OF ANALYSIS S2.1 Existing Sanitary Sewer Systems For analysis of existing sanitary sewer systems, hydraulic calculations shall be made using peak flow rates determined using parameters, criteria and formulas given below, assuming steady state hydraulic flow conditions. The hydraulic analysis of the existing system shall be based on: Available Pipe Capacity of: Qpipe capacity = 0.7 x Qfull capacity Every legal lot within the subject catchment area shall be assumed to have developed to the maximum potential of its current zoning or OCP designation regardless of whether the legal lot has an existing service connection or the amount of sewer flow it is currently discharging. The analysis of the sanitary sewer system shall be determined from the most upstream point in the subject catchment area to the point downstream where the total contributing population, including the proposed development, is at least ten times greater than the proposed contributing population. Where the theoretical calculated peak sewage flows exceed the existing Qpipe capacity, the Consulting Engineer will submit a report outlining proposed upgrading requirements to the existing sanitary sewer system for review by the Municipal Engineer. The additional inflow and infiltration component of the sewage flows in the existing system shall be the actual flow determined in the catchment area. S3 NEW SANITARY SEWER SYSTEMS Sanitary sewers shall be designed using the Peak Wet Weather Flow (PWWF). The PWWF is the sum of the Peak Dry Weather Flow (PDWF) and infiltration flow. City of Maple Ridge Design Criteria Manual SECTION S-SANITARY SEWER September 2015 Page 64 S3.1 Average Daily Flow (Dry Weather) Average dry weather flows (ADWF) for residential and non-residential areas should be based on specific data related to the development or zoning. In the absence of such data, use the following residential per capita flow and equivalent population factors: Residential 300 L/day/capita Single Family 2.8 persons/dwelling unit Multi Family 2.8 persons/dwelling unit Land Use Equivalent Population/Hectare (gross) Commercial: 120 people/ha Institutional: 200 people/ha Industrial: 200 people/ha If reliable information indicates that non-residential flows will be greater than the above rates, the higher flows shall be used in the design analysis. For identified commercial and institutional facilities, the average annual daily demands shown in the MMCD Design Criteria Manual may be used as a guide, subject to City approval. S3.2 Peak Dry Weather Flow (PDWF) The Peak Dry Weather Flow shall be calculated by the following formula: q P PF Q = 86,400 Where Q = Peak Dry Weather Flow (l/s) q = Average Daily Flow (Dry Weather) (l/day/capita) P = Population PF = MMCD Peaking Factor: PF = 6.75 P -0.11 For calculating the peak factor, non-residential areas shall be converted from hectares to capita using an equivalent population of 90 persons per ha. S3.3 Infiltration Rate An infiltration rate of 0.13 l/s/ha shall be added to the PDWF to determine the PWWF. City of Maple Ridge Design Criteria Manual SECTION S-SANITARY SEWER September 2015 Page 65 S4 PIPE FLOW FORMULAS Gravity Sewers: Manning’s formula shall be used to size gravity sanitary sewers. Refer to section on sizing of storm sewers for the relevant formula and roughness coefficients. Gravity sewer shall be sized such that the Peak Wet Weather Flow depth will not exceed 75% of the full depth of the pipe. Force mains: Hazen-Williams formula shall be used: C D2.63 S0.54 Q = 278,780 Where Q = rate of flow in l/s D = internal pipe diameter in mm (minimum 100mm) S = slope of hydraulic grade line in m/m C = friction coefficient = 100 S5 MANHOLES Manholes shall be required at:  all changes in grade  all changes in direction  all changes in pipe sizes  all intersecting sewers  all terminal sections  downstream end of curvilinear sewers Manholes shall be placed where future extensions are anticipated and shall be spaced no greater than 120m apart. Sanitary manhole rim elevations in off road areas shall be designed to be: a) above the adjacent storm manhole rim elevation b) above the surrounding ground so that infiltration from ponding will not occur S6 HYDRAULIC LOSSES ACROSS MANHOLES The following criteria shall be used: a) The springline of the downstream pipe shall not be higher than that of the upstream pipe. City of Maple Ridge Design Criteria Manual SECTION S-SANITARY SEWER September 2015 Page 66 b) Minimum drop in invert levels across manholes: (i) Straight run no drop required (ii) Deflections up to 45 degree 30mm drop (iii) Deflections 45 degree to 90 degree 60mm drop c) Manhole drops shall be provided as follows: Invert Difference Use Up to 0.25m Inside ramp 0.60–0.90m Outside ramp Over 0.90m Outside drop The applicable standard drawing details apply to manhole drops on pipes less than 600mm, incoming pipes 600mm and larger in diameter require special drop design. S7 TEMPORARY CLEAN-OUTS Temporary clean-outs may be provided at terminal sections of a main provided that: a) future extension of the main is proposed or anticipated b) the length of sewer to the downstream manhole does not exceed 45m c) the depth of the pipe does not exceed 2m at the terminal point Note: Clean-outs shall not be considered a permanent structure. S8 MINIMUM PIPE DIAMETER The minimum size of pipe shall be 200mm diameter, and no reduction in pipe size shall be made for pipes downstream, irrespective of grade provided on the pipe, unless specifically approved, in writing, by the Municipal Engineer. S9 VELOCITIES The minimum velocity flowing full or half full shall be 0.75m/s and 1.0m/s for inverted siphons. There is no maximum velocity. However, consideration must be given to scour problems where flow exceed 2.5m/s, and anchoring should be incorporated where the grades of the sewer are 15% or greater. S10 MINIMUM GRADE The grade of any sewer is governed by the minimum velocity required. However, the last section of a main that will not be extended in the future shall have a minimum grade of 1% where there are 8 or less service connections. City of Maple Ridge Design Criteria Manual SECTION S-SANITARY SEWER September 2015 Page 67 S11 MINIMUM DEPTH OF COVER The minimum cover over any main shall be 1m and traveled portion of roadway shall be 1.5m. The depth of the sewer must be sufficient to provide gravity flow service connections to both sides of the roadway and must allow for future extensions to properly service all of the upstream tributary lands for ultimate development. Where it is not feasible to service by gravity connection to front yard, a rear yard sewer may be required. S12 CURVILINEAR SEWERS Where permitted, horizontal curves will require a constant offset and shall be uniform throughout the curve. The radius of the curve shall not be less than 60m. The design velocity must exceed 0.91m/s. The minimum grade shall be 1% and each joint is to be located by survey. Refer to section on manholes for manhole location requirements. All curvilinear sewers shall be video tested as directed by the Municipal Engineer at the Developer’s expense to ensure proper grade and alignment. S13 SEWER LOCATION/CORRIDORS Sanitary sewers shall be located within the road right-of-way as noted in the applicable standard drawings for road cross-sections. When the sewer is required to cross private lands, the right-of-way shall be a minimum of 3m wide. Where both storm and sanitary sewers are in one right-of-way, the width shall be a minimum of 4.6m wide. When a sewer, manhole, valve chamber, or other appurtenances are located within a right-ofway, the Developer may, for maintenance purposes, be required to provide vehicular access from an existing municipal road. The maintenance access shall be constructed to the City’s standards adequate to support the maintenance vehicles for which the access is intended. Where an access is required, the access is to be located entirely on one lot. S14 UTILITY SEPARATIONS Refer to Section W – Water, W10 Clearance With Sewer Pipes for clearance with watermains. For clearances with other utilities such as Fortis BC, Telus, BC Hydro, cable, etc., consult the respective authorities. City of Maple Ridge Design Criteria Manual SECTION S-SANITARY SEWER September 2015 Page 68 S15 SERVICE CONNECTIONS a) Service connections shall be provided to each lot fronting the main and the face of curb marked with an “S” directly above the service. All services shall enter the main at a point just above the springline. b) Each connection shall only service one single lot. c) Connections to new mains shall be made using wye fittings. Connections to existing mains shall be made using saddles. d) The standard size for service connections shall be 100mm. e) The minimum grade of service connections from the main to the property line shall be 2% for 100mm and 1.5% for 150mm. All other sizes shall be based on minimum velocity of 0.75m/s. f) The minimum depth of a service at the property line shall be 1.0m and the maximum depth of a service at the property line shall be 2.0m unless otherwise accepted by the Municipal Engineer. g) Service connections may not be permitted into manholes. h) Inspection chambers (IC) are required for all residential connections and on flood plains and special areas, optional back flow prevention flap to be installed at upstream of IC. i) Sampling chambers are required for all industrial and light industrial connections. Sampling chambers will be required for commercial connections at the discretion of the Municipal Engineer. j) A manhole shall be required on all service connections where the size of the connection is greater than 200mm in diameter, unless the connection is more than two pipe sizes smaller than the main to which it is joining. Service connection exceeding 20m in length will be treated as a regular main. k) Direct connections to a Greater Vancouver Sewerage and Drainage District’s (GVS&DD, a branch of the Metro Vancouver) trunk or interceptor sewers may be permitted by the GVS&DD, at their sole discretion. When so permitted, connections shall comply with the criteria and details stipulated by the GVS&DD. The Engineer’s conditions of approval of the service connections and/or decision shall be final and shall override any lesser stipulations of Metro Vancouver. S16 SANITARY PUMP STATIONS If at all possible, the use of sanitary pump stations is to be discouraged. Any proposed use of pump stations must receive prior approval from the Municipal Engineer. City of Maple Ridge Design Criteria Manual SECTION S-SANITARY SEWER September 2015 Page 69 All sanitary pump stations must be located within a right-of-way outside the road dedication and away from creeks. The size, capacity and type of these stations will be dependent upon the development and catchment area involved. Generally, the following criteria shall be considered in the design of submersible duplex pump systems: a) All sanitary pump stations shall be designed with at least two pumps capable of handling the maximum flow conditions with one pump out. b) Each pump must be:  capable of passing solids up to 75mm in size using non-clog N-impeller  guide bars shall be hot-dipped galvanized steel  easily removed for maintenance  operate on a 208/600 volt electrical source (pump motors over 5 HP are to be 600 volt 3 phase type)  able to operate alternately and independently of each other c) Motor cables, power cables, etc. shall be continuous from within the pump station to within the kiosk. In no instance shall a cable be spliced. Only one cable is allowed in one conduit and all cables shall be properly secured. d) Separate level regulators are required as follows  pumps off  lead pump start  lag pump start  high level alarm (dry contact in pump control for telemetry) In addition to the above noted alarms, the pump control shall contain dry contacts for the telemetry of Pump No. 1 and No. 2 fail, and Pump No. 1 and No. 2 run time and pump running indicator. e) Level controls shall be ultrasonic detector (Milltronics Multi Ranger or acceptable alternative) and one float switch for high level. f) All auxiliary equipment and control panels shall be mounted in a suitable kiosk adjacent to the station. The kiosk shall be located not less than 1.2m and not more than 3m from the station lid. g) The control kiosk shall be designed to contain all control and watertight, and telemetry equipment on the front panel and all power equipment on the rear panel. The concrete base for the kiosk shall be a minimum of 75mm above finished grade. h) The kiosk shall contain a separate compartment for:  pump control City of Maple Ridge Design Criteria Manual SECTION S-SANITARY SEWER September 2015 Page 70  service entrances  fan and duct  isolated cable junction chamber to be vented with 150mm diameter pipe to the atmosphere. i) Check valves shall be all ball valves. j) The entrances to all stations must be provided with a suitable lock. The cover may be either aluminum or steel. The entrance should be 200mm above ground level where feasible but, in no case, more than 300mm above the ground and out of flood plains. k) Access into the stations shall be by an aluminum ladder. The location of the ladder shall not interfere with the removal and installation of the pumps, etc. The ladder shall be designed to extend and lock at least 1m above the station entrance. A platform is to be provided above the high water level float to permit wet well access wherever the total depth from ground level to wet well floor exceeds 2.4m, shall meet WorkSafe BC Regulations Including Confined Space Entry Practices. l) All wiring shall be explosion-proof, Class 1, Division 2, and electrical design and installation is subject to the acceptance of the Provincial Safety Inspector. Metal stations shall be protected by at least two 15 kg packaged magnesium anodes. m) Each station shall provide a minimum of 2 hours storage at peak wet weather flow or alternatively an automatic generator for standby power in case of power failures or P.S. > 30 l/s, all as directed by the Municipal Engineer. Provision for a telemetry system must be included for connection into the City’s telemetry system. n) All equipment must be CSA approved and have at least a one year guarantee for parts and labour. The supplier shall provide the City with three sets of operating and maintenance manuals complete with pump curves, detail drawings for meter and valves, and information sheets. All pumps must be factory-tested prior to installation and results to be provided. o) A 40mm water connection for cleaning purposes must be provided to the site complete with a backflow preventer within 10m. p) The roof and cover of the pump station should be designed to withstand an H2O loading unless adequate protection is provided. q) The control panel must incorporate with a Grouse Hinds male receptacle type and labeled (ex: APQ 1046–100 A–3wire–4pole), and a transfer switch for a standby power source. underground electrical wiring is required. r) The area around the station and all associated equipment or building shall be asphalted and not exceed 3% cross fall. The size of the area to be determined by the requirements for maintenance and a minimum of 1.5m clearance around structures. Access and turn-around shall be provided for maintenance truck. City of Maple Ridge Design Criteria Manual SECTION S-SANITARY SEWER September 2015 Page 71 s) The interior surfaces of all steel and fiberglass stations shall receive at least two coats of two components white epoxy enamel. t) The wet well bottom shall be corrosion resistant and benched to direct all solids into the pump suction. u) The pump control panel must incorporate the following indicator lamps: Condition Colour Reset Pump on 1 for each pump Green Pump fail 1 for each pump Red Manual Pump motor overload 1 for each pump Red Manual Motor winding high temperature 1 for each pump Red Manual Moisture sensor 1 for each pump Red Manual Power failure Red Manual High wet well level Red Manual All indicator lamps must be “push to test” type. v) An hour meter must be built into the panel for each pump and labeled. w) An ammeter must be provided for each pump, switchable to each phase for 3 phase systems. x) A complete set of spare circuit cards are to be provided where modular card-type pump controllers are used. S17 FORCE MAINS In conjunction with sanitary pumping facilities, the following criteria shall be noted in the design of force main systems. Velocity At the lowest pump delivery rate anticipated to occur at least once per day, a cleansing velocity of at least 0.9m/s should be maintained. Maximum velocity should not exceed 3.5m/s. Air Relief Valve An automatic air relief valve shall be placed at high points in the force main to prevent air locking. Termination Force mains should enter the gravity sewer system at a point not more than 50mm above the flow line of the receiving manhole. Manhole benching shall be a minimum of 200mm higher than the crown of the force main. The flow shall be discharged straight into the outflow pipe with no bends in the manhole. If this is not possible, an additional discharge manhole shall be constructed which flows by gravity to the receiving system. City of Maple Ridge Design Criteria Manual SECTION S-SANITARY SEWER September 2015 Page 72 Size The minimum size for force mains shall be 100mm diameter and utilizing roughness coefficient value of 100. Materials The material selected for force mains shall meet the Municipal standards and shall adapt to local conditions, such as character of industrial wastes, soil characteristics, exceptionally heavy external loadings, abrasion and similar problems. All force mains shall be designed to prevent damage from superimposed loads, or from water hammer or column separation phenomena. S18 AERIAL BRIDGES AND INVERTED SIPHONS Design of exposed bridge-type crossings for sanitary sewer or inverted siphons must be reviewed with the Municipal Engineer prior to design. The Design Engineer shall obtain written approval-in-principle, from the Municipal Engineer, for the proposed facility and, prior to proceeding with the design, obtain appropriate criteria and guidelines for the design. S19 ACCEPTED PRODUCTS Inspection Chambers Le-Ron Plastics100 x 200 7A 4-WOD or equivalent chamber 150 x 200 70A6W/OP Red 200-70A LID 086 lid Red 200-73A 08-H5 collar Terminal City Cast iron cover 250 diameter stamped with appropriate utility identification, complete with locking bolts (required in driveway only) City of Maple Ridge Design Criteria Manual September 2015 Page 73 SECTION W -WATER W1 WATER DISTRIBUTION SYSTEM W1.1 Community Water Supply Watermain design shall conform to the requirements of the Provincial Ministry of Health (MOH) and this Schedule. The system shall be designed to provide future peak domestic requirements and also shall provide adequate flows for fire protection. The required flow shall be the sum of the maximum daily domestic flow plus the required fire flow. W1.2 Private Wells Under the jurisdiction of MOH (604 476-7000) and the City of Maple Ridge Building Bylaw. City requires private wells to be drilled and not influenced by surface water. W2 DOMESTIC DEMANDS In the absence of reliable water consumption records or specific data related to the development or zoning of residential, industrial, commercial and institutional land, the following demand methodologies will apply. W2.1 Residential Demands Design populations used in calculating water demand shall be computed in accordance with the City's population predictions or with the planned development in the area to be served, whichever is greater. For lots smaller than 0.3 ha the “Per Capita Demand Method” will be used. For lots larger than 0.3 ha the “Per Capita Demand Method” or the “Population Plus Irrigation Area Method” will be used, whichever is greater Per Capita Demand Method Average Day Demand 600 litres/capita/day Max Day Demand 1200 litres/capita/day Peak Hour Demand 1800 litres/capita/day Population Plus Irrigation Area Method Average Day Demand 600 litres/capita/day Max Day Demand = Winter Base Demand + Irrigation Demand Winter Base Demand 350 litres/capita/day Irrigation Demand (max 0.3ha) 25,920 litres/ha/day Peak Hour Demand 2 times Max Day Demand City of Maple Ridge Design Criteria Manual SECTION W -WATER September 2015 Page 74 W2.2 Industrial, Commercial and Institutional Demands Design populations used in calculating water demand shall be computed using the following equivalent populations, design area will be based upon the gross site area: Industrial 90 capita/ha Commercial 50 capita/ha Institutional 90 capita/ha Average daily domestic flow 600 litres/capita/day Max Day Demand 1200 litres/capita/day Peak Hour Demand 1800 litres/capita/day For commercial and institutional facilities identified in figure 2.1 of the MMCD Design Guideline Manual the “Typical Demand” may be used as a guide, subject to City approval. W2.3 Hydraulic Calculations Hydraulic design calculations shall be based on the Hazen-Williams formula: CD2.63 S0.54 Q = ____________ 278,780 Where Q = rate of flow in 1/s C = toughness coefficient (minimum 110) D = internal pipe diameter in mm S = slope of hydraulic grade line in m/m W3 FIRE FLOW DEMANDS The requirements of this section are based on the publication "Water Supply for Public Fire Protection -A Guide to Recommended Practice 1991" published by Fire Underwriters Survey. Fire services to be designed by an engineer. W3.1 Properties Not Protected by Sprinklers The following are minimum fire flows for different types of developments where the development or adjacent developments are not protected by automatic fire sprinklers: Developments Required Fire Flow Single Family Residential 60 l/s Apartments, Townhouses 120 l/s Commercial 150 l/s Institutional 150 l/s Industrial 225 l/s City of Maple Ridge Design Criteria Manual SECTION W -WATER September 2015 Page 75 W3.3 Properties Protected by Sprinklers Where each existing and future building on a lot is or will be constructed with an automatic fire sprinkler system protecting the entire building, the minimum fire flow provided to that lot may be reduced to the greater of: a) the minimum fire flow calculated in accordance with the National Fire Protection Association Guide (13D) allowing for automatic fire sprinklers, or b) the minimum flow required to support the automatic fire sprinkler systems and all other water requirements for fire fighting purposes on the lot. Where a watermain is extended, each lot along the extension must be serviced in accordance with W3.1 or W3.2 based on the type of development permitted by the current zoning on each lot. Watermain extensions shall be sized in accordance with City requirements for its hydraulic network. W4 WATER PRESSURES Maximum allowable pressure 900 kPa Minimum pressure at Peak Hour Demand 300 kPa Minimum pressure anywhere in system 150 kPa during design Fire Flow and Max Day Demand All service connections shall be individually protected by pressure reducing valves in the dwelling. W5 HYDRAULIC NETWORKS Designs shall accommodate the ultimate development projections using either the Max Day Demand plus Fire Flow or the Peak Hour Demand, whichever has the greater effect on pressure and flow. Depending on the complexity and extent of the proposed distribution system, the City may require a hydraulic analysis design showing minimum flows and pressures. Pipe segments shall not be designed to have velocities exceeding 1.0m/s or head loss exceeding 1m per 100m of length under Max Day or Peak Hour design conditions, whichever is greater. The maximum desirable length of any permanent non-interconnected watermain shall be 85m any main exceeding 85m in length, shall be looped, except with the approval of the Municipal Engineer. The maximum length of a temporary non-interconnected watermain, in City of Maple Ridge Design Criteria Manual SECTION W -WATER September 2015 Page 76 the residential zones, shall be 150m. A temporary non-interconnected watermain is one that is reasonably expected to exist for a period of less than five years. In residential areas, watermains servicing fire hydrants shall be 200mm diameter or larger. Watermains 150mm in diameter may be permitted for domestic service on dead end roads where no further extension is planned with one hydrant only and blow-off. Watermains 100mm in diameter may be permitted for mains that do not service fire hydrants and are less than 80m. Wherever practical, watermains shall be looped. Dead-end mains should not be promoted. In commercial/industrial/institutional areas, the minimum watermain size shall be 250mm diameter. W6 PIPE MATERIAL All main pipes to be Ductile Iron pressure class 350 for size 100mm through 300mm, pressure class 250 for 350 -500mm and pressure class 200 for 600mm or bigger, and Tyton Joint AWWA C151 and C111(Cement Mortar Lined to AWWA C104). W7 CORROSITIVTY INVESTIGATION A geotechnical investigation for soil corrosiveness is to be carried out in accordance with the 10 point AWWA C105 evaluation for all proposed ductile iron or steel pipes. If the soils are expected to be corrosive, then measures shall be taken in the design and construction of the pipeline to prevent the corrosion pipeline and appurtenances. Corrosion protection measures must be approved by the Engineer. W8 DEPTH OF COVER The minimum cover over any watermain shall be 1.0m with 0.3m cover over valve stems. Valves larger than 400mm may be installed sideways with a 90 degree stem adapter. Maximum cover 1.4m unless justified. Where it is impractical to provide the minimum cover required, precast concrete slabs shall be used to protect the watermain against excessive loadings. The Design Engineer shall submit a design to show that the precast concrete slab is adequate for its intended purposes. Such slab shall be provided with lifting hooks for subsequent access to the watermain. All major road crossings shall be installed with carrier pipes. No concrete encasing shall be allowed. City of Maple Ridge Design Criteria Manual SECTION W -WATER September 2015 Page 77 W9 WATERMAIN GRADES The minimum grade for a main shall be 0.1%. The maximum grade shall be 8.0% unless provisions are made to anchor the pipe to the bottom of the trench with concrete poured in place as per the applicable standard drawings. W10 CLEARANCE WITH SEWER PIPES All cross over points with sanitary or storm sewers shall be indicated on the drawings. Where the watermain has less than 0.5m vertical clearance from any sewer pipes or ditch, a next higher class of pipe shall be used and a full pipe length shall be centered across the cross over point. The end joints of this pipe shall be wrapped with a petroleum tape product or poly wrapped in accordance with the following standards: ANSI/AWWA C214 (factory applied) ANSI/AWWA C209 (field applied) ANSI/AWWA C217 (petroleum tape) All materials used are to have zero health hazards The minimum horizontal clearance between a watermain and a sanitary or storm sewer shall be 3m. Where it is impractical to provide this minimum clearance, all affected joints shall be similarly protected.  minimum 1.0m clearance from any obstruction  not be built in curb line or future curb line W11 VALVES In general gate valves shall be located as follows: a) east side of tee and south if south of Dewdney Trunk Road and north if north of Dewdney Trunk Road, b) in a cluster at the pipe intersections, the minimum requirement shall be: (i)3 valves at "X" intersection (ii) 2 valves at "T" intersection to enable specific sections of mains to be isolated. c) Valves shall be provided in all legs of "X" or "T" intersections in industrial areas. d) Spacing of valves in industrial areas shall isolate no more than 1 hydrant or 2 service connections. e) Valves shall not be spaced more than 200m apart for single family residential areas or 150m apart for commercial areas. All other zones shall require special designs. City of Maple Ridge Design Criteria Manual SECTION W -WATER September 2015 Page 78 f) Not more than 1 hydrant is to be isolated per valve. g) Gate valves adjacent to tees or bends shall be flanged connections Valves shall be the same diameter as the main up to 300mm diameter. For mains larger than 300mm in diameter, valves shall be no more than one diameter size smaller. For mains larger than 450mm in diameter, valves shall be no more than two diameter sizes smaller. All direct bury mainline valves shall be gate valves. Butterfly valves shall only be used in special circumstances where approved by the Municipal Engineer and where gate valves are not practical. Valves larger than 500mm shall be provided with bypass valves. W12 HYDRANTS Require minimum 1.0m clearance from all obstructions and property lines with a clear line of site to the road carriageway. Fire hydrants shall be located in general at street intersections and at a maximum spacing of 180m in residential areas with no house further than 90m from a hydrant. In high density residential, commercial, and industrial areas, hydrants shall be located at a maximum of 150m or as approved by the Municipal Engineer. In mid-block locations, fire hydrants shall be located at the property lines. It shall be the Designer’s responsibility to ensure the design and proposed locations of the fire hydrants will not conflict with existing or proposed street lights, power poles, driveways, kiosks and other structures. W13 AIR VALVES Combination air valves shall be installed at the summit of all mains of 300mm diameter and larger except where the difference in grade between the summit and valley is less than 600mm. Combination air valves shall be sized as follows: Watermain Size Valve Size Up to 600mm 50mm Larger mains Special design Refer to the applicable standard drawing for air valve detail. All air valves shall be installed off the traveled portion of the road in a suitable chamber. W14 BLOW-OFFS Blow-offs are required at the ends of all watermains and at system low points. Refer to applicable standard drawing for details. Blow-offs for watermains larger than 200mm shall City of Maple Ridge Design Criteria Manual SECTION W -WATER September 2015 Page 79 require special design to have adequate flushing velocity. A minimum 100mm gate valve is required for blow-offs. Considerations will be made for discharging into ditches and streams so water can be treated prior to its release into environments. All tie-ins to be done by City forces. W15 THRUST BLOCKING AND JOINT RESTRAINTS Concrete thrust blocking shall be provided at valves, bends, tees, reducers, plugs, caps, and blow-offs as shown on the applicable standard drawing. Designer must design thrust blocks with due regard for pipeline pressure transients and expected test pressures. Thrust block calculations and soil bearing pressures shall be included in the first submission. Thrust block sizes shall be indicated on the design drawings. Joint restraining devices may be used with the approval of the Municipal Engineer in cases where conventional thrust blocking is not feasible, or to augment conventional thrust blocking where the possibility of disturbance exists. Design plans shall identify the type of restraining device to be used and clearly show the minimum required restrained pipe length. The Municipal Engineer may limit the size and number of taps permitted on a restrained length of pipe. W16 CHAMBERS Chambers or manholes containing valves, blow-offs, meters, or other appurtenances shall not be connected directly to any sanitary sewer. Such chambers or manholes shall be drained to the ground surface where they are not subjected to flooding by surface water, or to absorption pits, subject to adequate soils conditions. Chambers shall be capable of withstanding all possible thrust forces (e.g. fully closed valve thrust force) unless these thrust forces are restrained by features outside of the chamber. W17 SERVICE CONNECTIONS Minimum 38mm diameter copper tubing Type K annealed to ASTM B88M service connections shall be required for all lots. These connections shall typically be located at the centreline of the lot. A corporation stop shall be installed for each connection with 50mm diameter in size or smaller and all connections with 75mm and larger pipes required a check valve at the property line. The National Building Code stipulates the conditions for mandatory fire sprinkler systems for certain buildings. Where required, a Professional Engineer with experience in sprinkler system design shall size each water service connection to accommodate the anticipated fire City of Maple Ridge Design Criteria Manual SECTION W -WATER September 2015 Page 80 sprinkler installations. Designs are to conform to the National Fire Protection Association standards. W18 WATER METERS Water meters are required for all multi-family residential, commercial, industrial and agricultural developments or single family with in-ground swimming pools or in-ground sprinkling systems as per the Maple Ridge Water Service Bylaw. All water meter related installations must conform to all applicable specifications and designs contained in the most recent Engineering Department Water Meter Material Specifications and Design Guidelines available from the Engineering Department. W19 WATER SYSTEM LOCATION/CORRIDORS Watermains shall be located within the road right-of-way as noted in the applicable standard drawing for road cross-sections unless otherwise approved by the Municipal Engineer. When the watermain is required to cross private lands, the right-of-way shall be a minimum of 3m wide. When a watermain, manholes, valve chambers, or other appurtenances are located within the right-of-way, the Developer may, for maintenance purposes, be required to provide vehicular access from an existing municipal road. The maintenance access shall be constructed 3.0m wide complete with turn around and gate with lock and be adequate to support the maintenance vehicles for which the access is intended. Where an access is required, the access is to be located entirely on one lot. W20 PRVS, PRESSURE ZONES AND PUMPS These items shall be designed by an engineer in conjunction with City of Maple Ridge Engineering Department and will require water network modeling as directed by the Municipal Engineer. Design shall identify all necessary settings and include an operation and maintenance manual. W21 CHECK VALVES Where a check valve is required on a main line, it shall be designed with equal diameter bypass with a gate valve, riser and operator extension. Check valves shall be located off the main traveled portion of roadways, and with adequate access and working space. City of Maple Ridge Design Criteria Manual SECTION W -WATER September 2015 Page 81 W22 TEST POINTS AND CHLORINATION For the purpose of pressure testing, bacteriological and chlorination residual testing of all mains, a minimum of one test point shall be installed beside a line valve on each section of a main, between two valves. These test points shall consist of a 20mm corporation stop with a female outlet threaded for iron pipe. The corporation stop installed for an air valve may be used as a test point or as a bleed point. Locations of the test points shall be optimized to ensure thorough chlorination of a newly installed watermain. W23 ACCEPTED PRODUCTS Pipe-Mainline Ductile iron: C151 Tyton joint, mortar lined Pressure Class 350 or better. Exterior polyethylene encasement C105 where required Pipe-Service Copper tubing Type K annealed to ASTM B88M Fittings Terminal City ACS C153 ductile iron All fittings to include tie lugs and to be mortar lined Gate Valves Terminal City, Clow AWWA C509, or Mueller resilient seated c/w 150mm PVC cap drilled to fit under square on valve shaft, or approved equivalent gate valves conforming to AWWA C500. Note: Gate valves adjacent to tees or bends to be flanged connections. Fire Hydrants Terminal City C71P, Canada Valve Century, or Clow M93 Brigadier (Shut off: compression type only) Body: Marine Enamel Signal Red (General Paint code 16208) Caps: Marine Enamel White (General Paint code 16110) Pump Nozzle: “quick connect” STORZ type Saddles Robar 2706, Jones J969, Smith-Blair 317, Mueller DR2S or approved equivalent Corporation Stops Mueller, McDonald, Jones, Cambridge Brass “Q Style” – compression type only, with positive conductivity – must be ball style Meter Setters Mueller, Cambridge Brass, McDonald Brass, Jones or Ford Meter Box Co. “Q Style” ball types c/w handles, compression both ends, 20mm meter spacer, duel check valve. 15” high c/w extended outlet Service Boxes 300mm ductile iron or AE concrete approved base c/w 2 Terminal City ACS or TR ductile extensions and ductile iron cover marked as MR meter City of Maple Ridge Design Criteria Manual SECTION W -WATER September 2015 Page 82 Repair Couplings Ductile iron – Robar, Viking Johnson or Smith-Blair Stainless Steel – Robar, Mueller 520, or Canada Pipeline couplings epoxy or nylon coated stainless steel Concrete Meter Boxes Valve – MR Type – terminal City ACS or TR only Meters 50mm and under – AE Concrete approved base c/w Terminal City ACS or TR ductile iron extensions and cover Meters 75mm and over – Water Manhole Chamber Blow-offs (Temporary or Permanent) 4” only, and must be Kupferle model 7600 Air Valves Crispin, Valmatic, APCO – air valves must be combination air and vacuum Nuts and Bolts Stainless Steel Tie Rods Cadmium plated City of Maple Ridge Design Criteria Manual September 2015 Page 83 SECTION LT – STREET LIGHTING AND TRAFFIC CONTROL LT1 GENERAL A Professional Engineer with street lighting design experience shall prepare design of street lighting systems in compliance with MMCD, Illuminating Engineering Society (IES) and the City of Maple Ridge Design and Construction Documents. A copy of lighting calculations shall be submitted. The drawing is to note brief design data for each road. LT2 ILLUMINANCE AND CONFIGURATION Street lighting design shall conform to the following criteria and calculations shall meet the MMCD Roadway Lighting Figure: a) MMCD References to “Major Road” shall be substituted for “Arterial Road” classification. b) Intersection lighting shall be adjusted as per MMCD c) Rural lighting will be provided at identified hazards, intersections, bus stops, cross walks, other public facilities, and at other locations as directed by the Municipal Engineer. Where street lighting is being provided in rural developments, luminaires and poles shall meet City standards unless BC Hydro lighting is approved. d) Institutional and public facilities (e.g. schools, recreational facilities, libraries, etc.) shall be classified as High Pedestrian Conflict Areas e) For projects which are specific in providing night-time lighting for walkways and bikeways, the luminance shall be in compliance with the recommended levels in MMCD f) Lighting design shall follow recommended practices provided in “Guide for the Design of Roadway Lighting” published by the Transport Association of Canada. g) Mounting height on poles are to be as follows:  Davit Arterial 9.0m  Davit Collector 9.0m  Davit Local 7.5m  Post Top Local 6.0m h) Wherever possible street light pole offsets shall not be located within the sidewalk and located in favour of intersections, property corners and pedestrian walkways. i) Luminaires shall be 100W or 150W high pressure sodium unless approved by the Municipal Engineer. j) All electrical power shall be rated for 120 volts unless connecting to an existing system having a non-standard power rating. City of Maple Ridge Design Criteria Manual SECTION LT – STREET LIGHTING AND TRAFFIC CONTROL September 2015 Page 84 k) Street lights shall have full-cutoff optic (flat glass) lenses. l) The make and model of the luminaire upon which the illumination levels were calculated shall be specified on the drawings. m) Street lights shall be provided for walkways tunnels and lanes as and when directed by the Municipal Engineer. LT3 LUMINAIRES AND POLES All street lights shall have cobra type luminaires mounted on davit poles. Post top luminaires may be permitted in lanes or walkways. Luminaires and poles for special development areas or streetscape themes shall conform to the type and style approved by the Municipal Engineer. Where special street lights are installed, the Developer shall supply to the City one additional spare luminaire and pole for every ten units installed. Street light poles shall be located in favour of intersections, property corners and pedestrian walkways. LT4 UNDERGROUND DUCTS Underground wiring for street lighting shall be designed in accordance with the Canadian Electrical Code (Part 1) and all bulletins as issued by the BC Electrical Safety Branch, the Provincial Electrical Inspection amendments and any City codes or bylaws and other authorities having jurisdiction. The standard offset for the location of the underground street lighting ducts in road right-ofway shall conform to the applicable road classification standard drawing. The minimum depth for the underground ducts shall be 0.6m in boulevards and 0.9m below the finished grade of the roadway and shall be identified by yellow electrical hazard tape. It is the designer’s responsibility to ensure that the supply service to the street lighting system receives connection permit from BC Hydro, a copy of which shall be forwarded to the City. LT5 CIRCUIT SIZE Service bases shall service a maximum of 25 lights. Roads having staggered lighting shall have separate circuits on either side of the road. City of Maple Ridge Design Criteria Manual SECTION LT – STREET LIGHTING AND TRAFFIC CONTROL September 2015 Page 85 LT6 INTERCONNECTION CONDUIT 1-75 mm RPVC traffic signal interconnection conduit design shall be provided in conjunction with street lighting designs on arterial and collector classified roadways. The conduit shall be common trenched with the street lighting system conduit. Type 66 concrete pull boxes will be required at maximum 100m intervals. The conduits shall have a 6mm nylon pull string installed and capped ends. The Designer shall coordinate the design with the Traffic Technician to ensure the conduit system will be integral from intersection to intersection. LT7 DECORATIVE STREET LIGHTING The City has unique designated areas in which decorative street lighting is utilized to enhance the streetscape. Areas such as the Town Centre and the downtown core area and others have decorative lighting specific to these neighbourhoods. The City shall provide the Developer or Designer with generic details of the decorative lighting requirements and a list of approved suppliers for use in producing design drawings. The Developer or Designer will be required to submit the following as part of the decorative lighting design:  shop drawings of the street light poles proposed complete with pole design criteria, sealed by a Professional Engineer registered in BC  detailed information and specifications of the luminaires proposed  detailed information on pole accessories (banner arms, receptacles, baskets etc.)  8 ½ x 11 AutoCAD drawings detailing assembled pole and luminaire units  full size design drawings detailing the complete site installation LT8 TRAFFIC CONTROL LT8.1 General Traffic control devices, installed during and following the construction of a road, should support public safety, protect property, provide public convenience, and manage traffic flow. The Designer, when designing works for a new road or altering the function or physical characteristics of an existing road, should adhere to the requirements of Design Criteria Manual, Section R -Road, and the “Manual of Geometric Design Standards for Canadian Roads” TAC 1999. Traffic control devices must be accepted by the Municipal Engineer. City of Maple Ridge Design Criteria Manual SECTION LT – STREET LIGHTING AND TRAFFIC CONTROL September 2015 Page 86 LT8.2 Signal Timing Timing shall comply with the City of Maple Ridge Signal Timing Standard Practices Review February 15, 2005. LT8.3 Design Components The City of Maple Ridge Design and Construction Documents shall be used in conjunction with the BC Motor Vehicle Act Regulation, Division (23) Traffic Control Devices and the BC Motor Vehicle Act RSBC 1996, Chapter 318. It is assumed that the reader has a sound knowledge of traffic signal design. Refer to Part B, Traffic Signals, of the most current edition of the Manual of Uniform Traffic Control Devices for Canada (MUTCD) for information on traffic signal concepts and terminology. City of Maple Ridge Design Criteria Manual September 2015 Page 87 SECTION TP – STREET TREE AND BOULEVARD PLANTING TP1 GENERAL Design of street tree and boulevard planting shall be prepared by a Landscape Architect, registered with the British Columbia Society of Landscape Architects or a Landscape Designer. TP2 PLANTING REQUIREMENTS Street trees shall be of a species and spacing to be acceptable to the Environmental Technician. Boulevard plantings will be required in all boulevards where the boulevard is physically separated from the adjacent development by a continuous landscape screen or solid fence. TP3 PLANT SPACINGS Street trees shall be spaced from 10m to 15m apart depending on the species used in the design. Boulevard plantings shall be designed to fill in as a mass planting within 3 years of installation. A maximum spacing at installation shall be 1m on centre for No. 2 pot evergreen shrubs and 500mm on centre for 10cm pot evergreen ground covers. TP4 MINIMUM TREE PLANTING CLEARANCES Street trees in different road categories shall be planted at offsets shown in the standard drawings. In addition, street trees shall have a minimum distance from the following: (exemptions may be permitted if the site design does not allow these distances, and the Environment Technician approves) Lamp standards 6.0m Steel/wooden poles 3.0m Driveways 2.0m Catch Basins 2.0m Manholes, valve boxes, services 1.2m Storm 1.5m Sanitary 2.0m Water 1.5m Hydrants 2.0m Corners in line with 7.5m sight triangle Utility planting strip area (area between sidewalk and curb): Curb face 0.75 – 1.25m Edge of sidewalk 0.70 – 2.65m City of Maple Ridge Design Criteria Manual SECTION TP – STREET TREE AND BOULEVARD PLANTING September 2015 Page 88 Boulevard planting area (area between combined curb/sidewalk and property line): Curb face 0.75m Consideration should be given in locating trees within boulevard to avoid obstructing traffic signs. TP5 SPECIES SELECTION Street tree and boulevard planting design shall blend with existing plantings. Changes, if necessary should occur at intersections. Tree species selection shall be made from the list of street trees available from the Environmental Technician. Substitutions to this list will be considered when proposed by the Landscape Architect or Landscape Designer. Where trees are planted within 5.0m of overhead conductors they shall have a maximum mature height of 6.0m or less.