Delta, British Columbia is located in the Fraser River delta on the shores of the Pacific Ocean, just south of the City of Vancouver. Delta comprises mostly agricultural land, with typical ground elevations near sea level. Levees protect the area from potential floods from the Fraser River and tidal surges from the Pacific Ocean.
Of the 13,500 hectares (ha) watershed, 6,300 ha is active agricultural land, 3,500 ha is the environmentally sensitive Burns Bog, and the rest is a mix of urban and industrial developments and transportation corridors.
The objectives of this hydraulic analysis include:
- Support the design and implementation of an SFPR drainage system that provides only beneficial impacts to the existing Corporation of Delta drainage and irrigation system
- Enhance the irrigation system by a four‐fold increase in supply capacity, allowing only high‐quality (low‐salinity) water to enter the system
- Improve water retention and management for Burns Bog
In Drainage mode, the primary measurement of the system’s hydraulic performance is the maximum water surface elevation during critical storm events. The performance objective is to
achieve lower maximum water surface elevations anywhere in the impacted watershed (upstream or downstream of the SFPR project) than would occur during the same storm events in the existing system.
For Irrigation mode, the objectives are to: 1) deliver increased demand to anywhere in the system within a predefined range of water surface elevations, and 2) ensure that flooding will not occur during summer storm events when the channel system is filled with irrigation water. The objectives for Burns Bog are to: 1) limit winter flood elevations to prevent external flow into the Bog, and 2) optimize water retention during the transitional period (late winter to early summer) to maximize wetting of the Bog during the dry summer period.