Water Services

Windsor Lake Water Treatment Facility (WTF)
Bay Bulls Big Pond Water Treatment Facility (WTF)
Petty Harbour Long Pond Water Treatment Facility
Water Distribution
Water Monitoring

The City of St. John’s is committed to bringing the highest quality of water service to all of its residents and visitors. From this page, you can find information on all aspects of our water programs, testing and delivery. 

The City of St. John’s is supplied its drinking water from the Broad Cove River and Windsor Lake, Bay Bulls Big Pond and Petty Harbour Long Pond.

Windsor Lake Water Treatment Facility
The Windsor Lake Wafer Treatment Facility 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.

Treated water from Windsor Lake is either pumped or gravity-fed to homes or businesses in the east end and downtown areas of St. John’s.

Fluoride is not added to City of St. John’s drinking water.

Bay Bulls Big Pond Water Treatment Facility
The Bay Bulls Big Pond (BBBP) Water Treatment Facility collects raw water from the Bay Bulls Big Pond watershed and pumps it to the Main Treatment Building via the Low Lift Pump Station. The treatment process consists of screening, ozone disinfection, filtration through a rapid gravity dual media filter, pH adjustment using hydrated lime, and chloramine disinfection using ammonia and chlorine. The system includes a Dissolved Air Flotation (DAF) Pretreatment Facility with alkalinity enhancement. 

The rated capacity of Bay Bulls Big Pond is 85,000 cubic metres per day.

Fluoride is not added to the Regional Water System’s drinking water.

Petty Harbour Long Pond Water Treatment Facility
Petty Harbour Long Pond Water Treatment Facility is the City's newest water treatment plant. Construction was completed in 2015.The treatment process consists of screening, filtration and disinfection through a a rapid gravity dual media filter, pH adjustment using hydrated lime, and chloramine disinfection using ammonia and chlorine.The system includes a Dissolved Air Flotation (DAF) Pretreatment Facility with alkalinity enhancement. 

The rated capacity of Petty Harbour Long Pond is 14,500 cubic meters per day.

Fluoride is not added to City of St. John’s drinking water.

Water Distribution
The City of St. John’s owns, operates and maintains a vast distribution infrastructure that consists of approximately 460 km of water mains, 3,070 hydrants, 8,955 valves and other related system infrastructure.

Water Monitoring
Each water treatment facility has its own Water Quality Laboratory staffed by qualified lab technologists, who work closely with the system operators to monitor the quality of water throughout the treatment process and the distribution system. Samples are collected routinely from each of the treatment facilities and throughout the distribution system, and are then analyzed for microbial, chemical and physical parameters to ensure the safety and integrity of the drinking water system.