Duffin Creek Water Pollution Control Plant
The Regional Municipalities of York and Durham jointly own the Duffin Creek Water Pollution Control Plant (WPCP), located on the shore of Lake Ontario in the City of Pickering, Ontario. This facility, which receives and treats 90 per cent of the wastewater generated by York Region, as well as wastewater from Pickering and Ajax in Durham Region, is a critical component of the York Durham Sewage System (YDSS). The YDSS was first constructed by the Province of Ontario in the late 1970s and early 1980s. The idea for this centralized sewage treatment system dates  back to 1965 when the province decided that no additional sewage treatment facilities would be built on the Don and Rouge Rivers and Duffins Creek. The YDSS converges at the Duffin Creek WPCP and discharges clear, treated wastewater to Lake Ontario. The Duffin Creek WPCP has undergone significant expansion and performance upgrades over the past several years to meet growth needs in both Regions. In 2006, to meet the identified future needs and the requirements to accommodate approved growth, York and Durham Regions completed a Schedule C Municipal Class EA following Ontario Environmental Assessment Act requirements to expand plant capacity  to 630 million litres per day (ML/d). Projections indicated that an expansion was required to accommodate expected growth in York Region to 2035. Referred to as the Stage 3 Expansion, this project increases wastewater treatment capacity at the WPCP from its previous capacity of 420 ML/d to 630 ML/d (annual daily average flow) At approximately 9:30 AM local time on 21 January 2014, an explosion occurred and thick black smoke could be seen rising from the building. All employees have been accounted for and no fatalities were reported.