GUIDANCE DOCUMENT: City of Chilliwack Policy and Design Criteria Manual for Surface Water Management (released 2002)
Note to Reader:
The City of Chilliwack’s Policy and Design Criteria Manual for Surface Water Management, released in 2002, serves two purposes:
- provide a comprehensive framework that will guide the development of individual Master Drainage Plans over a multi-year period
- provide land developers with specific direction in undertaking the stormwater component of sustainable urban design.
The driver for the Manual was large-scale land development planned for the City’s Eastern Hillsides. The Manual content has been, and continues to be, tested and refined on the basis of Chilliwack-specific case study applications.
Surface Water Management in Chilliwack
The City of Chillwack’s Manual was developed through an inter-departmental and inter-agency process that also included community participation.
“Through this process, the group developed a common understanding regarding core concepts. This resulted in consensus on the vision and the direction of the Manual, particularly with respect to the framework that the Manual provides for future rainwater-related action in the City of Chilliwack. The Manual replaced the drainage section of the Subdivision and Development Control Bylaw,” stated Dipak Basu, Land Development Engineer, in 2002.
“The process went on for two years. The realtors, developers, engineers and surveyors were all invited to participate and make their comments known.
“We showed the benefits of maintaining the water table, the watercourse, the habitat and allowing the fish to survive and flourish. By the time the document was finalized, the developers were quite knowledgeable about it and were willing to give it a try to see how the system worked.
“The Front End of the Manual summarizes key information that City staff, elected officials and land developers need in order to understand and implement the City of Chilliwack’s approach to stormwater management.”
To Learn More:
“The Manual was developed as a case study application of Stormwater Planning: A Guidebook for British Columbia, a collaborative effort of an inter-governmental partnership that was initiated by local government,” added Kim Stephens, project manager and principal author of the Guidebook. He was also project manager for the Chilliwack Manual. Today, he is the Executive Director, Partnership for Water Sustainability in BC.
“Through interaction with the Chilliwack community during its development, the Manual also provided a feedback loop for the Guidebook process. The Manual incorporated the content of the Bylaw that it replaced, and is designed to manage both flood risk and environmental risk,” emphasized Dipak Basu.
Stormwater Planning: A Guidebook for British Columbia
In 2002, the provincial government released Stormwater Planning: A Guidebook for British Columbia. This established a new direction for urban hydrology and drainage engineering. Introduction of the Water Balance Methodology enabled the setting of performance targets for rainfall capture, runoff control and groundwater recharge:
If we manage the runoff volume, and if we mimic the natural flow pattern in streams, then we can… prevent increased stream erosion, prevent increased risk of flooding, and protect aquatic habitat.
The Guidebook introduced the Integrated Strategy for managing the complete spectrum of rainfall events (see image below). The Integrated Strategy expanded the scope and responsibility of drainage practice to include stream health.
TO LEARN MORE:
To read an article written by Geoff Gilliard in Spring 2003, and published in Input Magazine by the Real Estate Institute of BC, download A recipe for stormwater management – The Stormwater Planning Guidebook helps make land develolpment compatible with stream protection