Photo by Linda HeronPhoto Credit

Heywood Generating Station, Twelve Mile Creek

Heywood Generating Station (7.2 MW) – St. Catharines: Twelve Mile Creek

Hydro Redevelopment – Expansion – HESOP

The Heywood Generating Station is a two-unit hydroelectric station located on Twelve Mile Creek in St. Catharines. Cofferdam and excavation work for the power house started in 1987. Major construction was complete by October 1988 and the station started producing electrical power in March 1989. The station was constructed in between the existing spill structure and the existing masonry wall of Lock 1 from the Third Welland Canal. The station has an installed capacity of 5.75 MW at a head of 3.4 metres.

Heywood is located downstream of OPG’s Decew Falls GS #1 and #2. The OPG stations typically pass 7,600 to 8,100 CFS of water into 12 Mile Creek. OPG have first rights to water and adjust flow at their discretion. Martindale Pond, located at the end of 12 Mile Creek, is the head pond for the Heywood. The forebay includes a channel from Martindale Pond to Heywood. The watercourse providing flow through Heywood originates in Lake Erie and flows into Lake Ontario.

A concrete Bullnose separates water flow in the forebay between the spill structure to the east and the power house to the west. The spill structure beside the power house is equipped with four gates for spilling water. Steel trash racks prevent large debris and ice from passing through the turbines.

Heywood is connected to the Horizon Utilities 15kV circuits 40M10 and 40M25. The station is typically connected to the 40M10 circuit.

Location: St. Catharines
River System: Twelve Mile Creek
Nameplate Capacity: 5.75 MW
OPA Contracted Capacity: 7.2 MW
Operator: St. Catharines Hydro Generation Inc.
Technology: Hydroelectric
Turbines: Two open-pit propeller turbines
Originally Built: 1987
Coordinate: 43°11’56.32″N, 79°15’57.02″W