Waste water treatment plant (WWTP) Ditch and Culvert Improvements


PLDD regarded existing ditch; installed bioretention swale to provide treatment for flows from parking area, and installed a footbridge.

The ditch from Oak Bay Road on the north side of the PLA property that carries drainage from Oak Raod, Swansonville Road and the Rainier to Oak Bay Greenbelt had inadequate conveyance capacity. This project obtained an easement to install and maintain a new ditch with increased capacity to convey the drainage to the point of connection with the stormwater outfall to Ludlow Cove that starts at the Wastewater Treatment Plant. The ditch was lined with rock to prevent erosion and subsequent sediment deposition into Ludlow Bay.

Culvert near the Waste Water Treatment Plant after construction
flow during Jan 2016 storm; looking west of bridge
flow during Jan 2016 storm; looking east of bridge