CANSnet Project Preview: NL21-0067 – Windsor Lake Water Treatment Plant Building Extension

Project Highlights:

Owner: City of St. John’s

Location: St John’s, NL

CANSnet ID: NL21-0067

Pipeline Connection:  PL21-0055NL

Closing Date: April 7, 2021 at 12:30 p.m. AST

About the Project:

The City of St. John’s is planning to expand its current wastewater treatment facility to include secondary processes. The facility currently serves residents in St. John’s, Mount Pearl and Paradise.

The Windsor Lake Wafer Treatment Facility currently treats raw water collected from the Broad Cove River and Windsor Lake watersheds. The Little Powers Pond Pump Station pumps raw water from the Broad Cove River watershed and transfers it directly into the Windsor Lake watershed. The raw water to be treated is then taken from Windsor Lake and is pumped up to the Main Treatment Building via the Low Lift Pump Station. The treatment process consists of alkalinity enhancement with hydrated lime and carbon dioxide, screening, membrane microfiltration, primary disinfection using ultraviolet light and secondary disinfection with chlorine.

The rated capacity of Windsor Lake is 70,000 cubic metres per day in the summer and 53,500 cubic metres per day in the winter. The difference in capacity over the seasons is due to the viscosity changes in water as it gets colder. Learn more about the facility here.