Urban Stormwater Management


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You have selected this document because your project involves Urban Stormwater Management activities in or about a stream. Urban stormwater management objectives include maintenance of watercourse health, habitat and aquatic life as well as opportunities for human uses of water by mitigating the effects of urban development. To achieve these objectives activities should include maintenance of natural hydrologic cycles, prevention of increased risk of flooding and erosion and protection of water quality. Urban stormwater management activities include:
  • storm sewer outfall construction or maintenance; and/or,
  • drainage tile outlets installation or cleaning.
When planning your project, develop designs and select locations to minimize potential impacts to fish and fish habitat. If your works are outside the scope of this Guidebook then a MOE Approval application must be completed and DFO contacted to determine if a review and/or Authorization under the Fisheries Act is appropriate.

How to proceed with your Urban Stormwater Management Project

The following steps will help guide you through the provincial and federal Notification, Approval and/or Authorization process for Urban Stormwater Management works:

Does your project involve Urban Stormwater Management in or about a stream?
Proceed to Introduction to reselect project appropriate activity
or
Contact your local MOE and/or DFO representative for assistance.
Have you considered all applicable Legislation, Regulations and Policies?
Proceed to Introduction for further details on Legislation, Regulations, Policies, Avoidance of HADD under the Fisheries Act and applicable Region Operational Statement(s)
Proceed to BMP Section of this document and apply relevant BMPs and Conditions to help your project adhere to the required Standards and Conditions.
Proceed to BMP Section of this document and apply relevant BMPs and Conditions to help your project adhere to the required Standards and Conditions.
Proceed to BMP Section of this document and apply relevant BMPs and Conditions to help your project adhere to the required Standards and Conditions.
Submit MOE Notification
No DFO Notification Required
No DFO or MOE Notification Required

Best Management Practices

The following Best Management Practices (BMPs) are methods, that if followed, will help ensure your project minimizes potential impacts to fish and fish habitat and will provide a standard level of protection to the aquatic and terrestrial environment potentially affected by your project.

It is the responsibility of the proponent/developer to ensure that they are in compliance with all applicable legislation. There are three (3) types of BMPs you should consider:

  1. General BMPs and Standard Project Considerations applicable to any project;
  2. Urban Stormwater Management specific BMPs (below); and,
  3. Supportive information applicable to project design, implementation and Urban Stormwater Management techniques.

General Project BMPs and Standard Project Considerations

Please proceed to the General BMPs and Standard Project Considerations section to review considerations applicable to your project.

Urban Stormwater Management Specific BMPs

To achieve the required Standards and objectives that your activity must meet, apply the following BMPs as applicable to your works. To reduce impacts on fish and wildlife habitats and populations, your Urban Stormwater Management activities must consider:

A. Storm Sewer Outfall Construction

Design

USM01 ensure General BMPs and Standard Project Considerations have been consulted and appropriately applied prior to commencement of work;
USM02 ensure construction activities adhere to Regional Timing Windows to prevent disruption of fish and wildlife habitat;
USM03 conduct a hydraulic analysis using a Qualified Professional prior to outfall construction to ensure that discharge velocities to watercourses does not produce scour and damage to fish habitat;
USM04 conduct a feasibility evaluation, using a Qualified Professional, of the channel downstream of a storm sewer outfall if the discharge velocity is expected to exceed 1 m/s;
USM05 ensure the discharge velocity from an apron or erosion control medium to a watercourse does not exceed the flow rate suitable to maintain stream morphology;
USM06 include appropriate water energy dissipation structures in construction design to aid in erosion control (see Section iii: Supportive Information for further information);
USM07 design outfall structures to minimize direct and indirect impacts to other properties or services;
USM08 design the outfall structure to minimize any thermal impacts by using shading vegetation and avoiding excessive rip rap (see Section iii: Supportive Information for further information) and concrete;
USM09 design storm sewer outfalls greater than 60 cm in diameter with a protected, free swinging, weighted grate to limit human and wildlife access and allow debris materials to be discharged;
USM10 design protective gratings to break away under extreme hydraulic loads in the case of blockage;
USM11 ensure an erosion and sediment control plan is developed by a Qualified Professional and implemented prior to site preparation and construction;
USM12 design and locate works in areas that enable access for maintenance activities and minimize impacts to riparian and watercourse areas;

Operational

USM13 minimize impacts to the existing riparian vegetation and/or alterations to the channel and active floodplain and associated fish and wildlife habitats when constructing or maintaining outfalls;
USM14 ensure construction works are undertaken and completed in such a manner as to prevent Harmful Alteration, Disruption or Destruction (HADD) to fish habitat through the release of sediment-laden water in any ditch, watercourse or storm sewer;
USM15 minimize erosion and discharge flow impacts to the channel by directing the discharge to a maximum 45 degree angle to downstream flow;
USM16 do not disturb stream banks that can expose underlying soils, cause silt to enter the stream or result in loss of fish habitat;
USM17 compact any fill below the outlet to the density of the surrounding undisturbed material;
USM18 ensure material removal does not lead to stream channel instability or increase the risk of Harmful Alteration, Disruption or Destruction (HADD) of fish habitat or sedimentation into the watercourse;
USM19 prevent erosion of outlets by reinforcing/armouring them with rip rap or other appropriate measures (see Section iii: Supportive Information for further information). If utilizing reinforcement/armouring measures consider the following:
  • place large, durable, clean, suitably graded and sized angular rocks (rip rap) into the eroding area at the outlets only;
  • carefully unload rocks and key into place (if placing rocks along the embankment) above the high water mark (HWM);
  • implement appropriate erosion and sediment control measures and maintain their functionality;
  • do not obtain rocks from below the high water mark (HWM) of any water body;
  • install rip rap at a similar slope as the stream bank to maintain a uniform stream bank slope and natural stream alignment;
  • use acid-free rocks; and,
  • ensure rip rap does not constrict the channel width or flow.

Post Works Mitigation

USM20 grade, stabilize and revegetate all disturbed areas upon completion of work to prevent surface erosion and siltation to the stream;
USM21 remove temporary erosion and sediment control measures within 30 days of final site stabilization;

B. Storm Sewer Outfall Maintenance

Design

USM22 ensure General BMPs and Standard Project Considerations have been consulted and appropriately applied prior to commencement of work;
USM23 ensure maintenance activities adhere to Regional Timing Windows to prevent disruption of fish and wildlife habitat;

Operational

USM24 inspect rip rap outlet structures after heavy rain (greater than 7.6 mm/hour) to observe signs of erosion or structural damage and repair immediately to prevent further problems;
USM25 add rip rap as needed to maintain the intended outfall function (see Section iii: Supportive Information for further information on rip rap installation);
USM26 immediately conduct all repairs involving structural damage or erosion to the outlet or rip rap structure to prevent further damage and maintain function;
USM27 ensure maintenance works are undertaken and completed in such a manner as to prevent Harmful Alteration, Disruption or Destruction (HADD) to fish habitat through the release of sediment-laden water in any ditch, watercourse or storm sewer;

Post Works Mitigation

USM28 ensure storm sewer outfalls are routinely inspected (at least twice a year) in the spring, fall and after severe storms to ensure they remain free-flowing and unclogged;
USM29 drainage outlets must be kept clean and free of debris;

C. Drainage Tile Outlet Installation

Design

USM30 ensure General BMPs and Standard Project Considerations have been consulted and appropriately applied prior to commencement of work;
USM31 design tile drainage outlets to not impede normal drain flow by angling to a maximum 45 degree angle to downstream flow;
USM32 design tile drainage outlets at least 0.3 m (1.0 ft) above the normal water level of the stream;
USM33 ensure an erosion and sediment control plan is developed by a Qualified Professional and implemented prior to site preparation and construction;
USM34 ensure drain material used is resistant to degradation by ultraviolet light and conforms to industry standards;
USM35 utilize an anti-seepage collar in areas of unstable soil to prevent bank washout and Harmful Alteration, Disruption or Destruction (HADD) to fish habitat;

Operational

USM36 utilize non-perforated sections of pipe under riparian areas to decrease the need for maintenance due to root obstruction;
USM37 keep the number of tile drainage outlets to a minimum by combining drainage lines into one main collector line;
USM38 utilize flush mounted outlet pipes to reduce bankslope damage resulting from ice and floating debris;
USM39 prevent erosion by extending the tile drain at least 0.15 m (0.5 ft) into the outlet pipe and ensuring the joint between the pipes are properly sealed (see Section iii: Supportive Information: Tile Drainage Outlets);
USM40 do not disturb stream banks that can expose underlying soils, cause silt to enter the stream or result in loss or damage to fish habitat;
USM41 compact any fill below the outlet to the density of the surrounding undisturbed material;
USM42 ensure material removal does not lead to stream channel instability, increase the risk of sedimentation to the watercourse;
USM43 prevent eroding outlets by reinforcement/armouring them with rip rap or other appropriate measures (see Section iii: Supportive Information for further information). If utilizing reinforcement/armouring measures consider the following:
  • place large, durable, clean, suitably graded and sized angular rocks (rip rap) into the eroding area at the outlet only;
  • carefully unload rocks and key into place (if placing rocks along the embankment);
  • implement appropriate erosion and sediment control measures and maintain their functionality;
  • do not obtain rocks from below the high water mark (HWM) of any water body;
  • install rip rap at a similar slope as the stream bank to maintain a uniform stream bank slope and natural stream alignment;
  • use acid-free rocks; and,
  • ensure rip rap does not constrict the channel width or flow.
USM44 ensure tile drainage outlets are routinely inspected (at least twice a year) in the spring, fall and after severe storms to ensure they remain free-flowing and unclogged;

Post Work Mitigation

USM45 mark all drain outlet locations with a highly visible indicator;
USM46 the drainage outlet must be kept clean and free of debris;
USM47 remove temporary erosion and sediment control measures within 30 days of final site stabilization;
USM48 remove trapped sediment to a stabilized site landward of the watercourse;
USM49 monitor water quality of the outlet water as per the B.C. Ministry of Agriculture and Food Drainage Factsheet (see Section iii: Supportive Information: Maintenance and Checking of Performance of Subsurface Drainage Systems, Inspection of Subsurface Drains section) as unusually coloured water may indicate drainage failure;
USM50 grade, stabilize and revegetate all disturbed areas upon completion of work to prevent surface erosion and siltation to the stream;

D. Drainage Tile Outlet Cleaning

Operational

USM51 install a sediment trap downstream of the outlet to collect potentially deleterious water and prevent Harmful Alteration, Disruption or Destruction (HADD) of fish habitat; and,
USM52 removed debris and sediment material from the outlet landward of the watercourse so it will not enter the stream and cause Harmful Alteration, Disruption or Destruction (HADD).

Supportive Information

The following sources provide you with additional planning, design, implementation and review advice for a variety of project-specific activities. Please follow the appropriate links to obtain further information on your project specific activity.

General Considerations

Pacific Region Operational Statements Develop with Care: Environmental Guidelines for Urban and Rural Land Development in British Columbia, B.C. Ministry of Environment (PDF 842KB) Best Management Practices Guide for Stormwater, GVRD Land Development Guidelines for the Protection of Aquatic Life, DFO Pacific Region (PDF 2.79MB)

Urban Stormwater Management Additional Information

A Guidebook for British Columbia: Stormwater Planning (Chapter Six), B.C. Ministry of Environment (PDF 968KB) Aggregate Operators Best Management Practices Handbook (Chapter 7), B.C. Ministry of Energy Mines and Petroleum Resources Conveyance and End of Pipe Measures for Stormwater Control, Federation of Canadian Municipalities (PDF 3.68MB) Design Criteria Manual, City of Surrey Engineering Department (PDF 6.73MB) Energy Dissipator BMP #17, Erosion and Sediment Control, Alberta Infrastructure and Transportation (PDF 508KB) Stormwater Best Management Practices (BMPs) for Selected Industrial Sectors in the Lower Fraser Basin, Fraser River Action Plan (2.38MB) Stormwater Management Policy and Design Manual, City of Coquitlam (PDF 2.85MB)

Rip Rap Design & Techniques

Rip Rap as Bank Stabilization Above High Water Level, B.C. Ministry of Transportation (PDF 399KB) Rip Rap Design and Construction Guide, B.C. Ministry of Environment (PDF 10MB)

Tile Drainage Additional Information

Agency Contact Requirements for Constructed Ditch Maintenance, Constructed Ditch Factsheet No. 3, Drainage Management Series, B.C. Ministry of Agriculture and Lands (PDF 278KB) Constructed Ditch Maintenance, Constructed Ditch Factsheet No. 5, Drainage Management Series, B.C. Ministry of Agriculture and Lands (PDF 312KB) Drainage Management Guide, B.C. Ministry of Agriculture and Lands (PDF 926KB) Farm Tile Drains and Tree Roots, Ontario Ministry of Agriculture, Food and Rural Affairs Tile Drainage Outlets, Ontario Ministry of Agriculture, Food and Rural Affairs Iron Ochre Problems in Agricultural Drains, Drainage Factsheet, B.C. Ministry of Agriculture and Lands (PDF 355KB) Suitability of Using "End of Pipe" Systems to Treat Farm Tile Drainage Water, University of Guelph (PDF 35KB) Tile Drainage, Manitoba Agriculture, Food and Rural Initiatives Tile Drainage-Questions and Answers, Ridgetown College, University of Guelph (PDF 33.4KB)
Where to start?

If you are unfamiliar with Instream Works, please use the interactive Introductory flowchart to help guide you through the process.

Glossary

Important words, denoted by blue underlined text are defined in the glossary.

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More information...

See the Supportive Information section at the end of this document for links to other websites and documents.