Is a Pickering address in a regulated flood area, and whose map says so?

The Toronto and Region Conservation Authority's jurisdiction takes in the Duffins Creek, Petticoat Creek, Carruthers Creek and Rouge River watersheds, among others, and its own table puts 95% of Pickering's population inside it. Its Regulated Area Search takes an address or postal code; it says not every regulated area is mapped and a feature doesn't have to be mapped to be regulated, and it links a Flood Plain Map Viewer. TRCA says that under the Building Code Act its permit is needed before the municipality issues a building permit for work in its regulated area, so its permit doesn't replace the City's.

The Central Lake Ontario Conservation Authority names the City of Pickering among its municipal partners; its watershed runs from the Ajax and Pickering boundaries east to Clarington and north to the crest of the Oak Ridges Moraine. Its regulation area mapping, endorsed by its board in November 2025, shows valleylands, wetlands, watercourses and areas subject to flooding and erosion, and it says additional dwelling units, new or enlarged structures, fill and grading near a stream or wetland may need its permit. A regulated-area result governs permits for work near water; it is not a forecast that a home will flood, and a home outside the mapped area can still take water through a basement. Under the Conservation Authorities Act as amended in 2026, the Toronto and Region authority and the Central Lake Ontario authority are to join the Central Lake Ontario Regional Conservation Authority on 1 February 2027 or a later date set by regulation.

• TRCA Regulated Area Search: the address search for the Toronto and Region Conservation Authority's regulated area, with a link to its Flood Plain Map Viewer
• About TRCA: jurisdiction: the authority's watersheds and the share of each municipality's population inside them
• TRCA: apply for a permit: the authority's permits, needed before a municipal building permit in its regulated area
• About CLOCA: the Central Lake Ontario authority's watershed and municipal partners
• CLOCA regulation area mapping: the authority's regulated area mapping, endorsed November 2025
• CLOCA inquiries and permits: what may need the authority's permit, and how to ask staff
• Bill 97, Plan to Protect Ontario Act (Budget Measures), 2026: Schedule 3 amends the Conservation Authorities Act; the transition date is 1 February 2027 or a later date set by regulation
• Regional conservation authority boundaries (ERO 025-1257): the Province's decision of 10 March 2026 on which authority joins which of the nine regional authorities
• Ontario Regulation 41/24: Prohibited Activities, Exemptions and Permits, the regulation behind every conservation authority's regulated area

Conservation-authority regulated-area and flood plain checks are not currently included in our reports, so for a Pickering home the authorities' own maps are the place to look. The full report's water and flooding group does cover past floods seen by satellite, nearby creeks, rivers and ponds, and mapped wetlands for any Pickering address.

What we cover, city by city See the sample report