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

Two conservation authorities share Aurora. The Lake Simcoe Region Conservation Authority's planning page lists the Town of Aurora in its jurisdiction, and its lookup shows whether a property is regulated, with staff to answer by phone or email; it says regulated land may contain hazards such as flood-prone or erosion-prone land, watercourses, shorelines and wetlands, and that because watershed boundaries don't follow municipal boundaries some towns are regulated by two authorities. The Toronto and Region Conservation Authority's own table puts 4% of Aurora's population inside its jurisdiction, and its Regulated Area Search takes an address or postal code; it says not all regulated areas may be mapped.

Both authorities issue permits under Ontario Regulation 41/24 for work such as building, site grading or placing fill in a regulated area. Neither permit replaces the Town's: the Lake Simcoe authority says the municipality may require its own permit, and the Toronto and Region authority says a municipality cannot legally issue a building permit until its permit or clearance has been obtained. A regulated-area result governs permits for work near water, such as additions, decks and grading; 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 Lake Simcoe Region authority is to join the Lake Huron Regional Conservation Authority, and the Toronto and Region authority the Central Lake Ontario Regional Conservation Authority, on 1 February 2027 or a later date set by regulation.

• LSRCA: planning: the Lake Simcoe Region authority's municipalities and its permits under Ontario Regulation 41/24
• LSRCA: for realtors: the authority's property lookup and its note on watershed boundaries
• LSRCA: do I need a permit: the authority's permits, and its note that the municipality may require one
• About TRCA: jurisdiction: the authority's watersheds and the share of each municipality's population inside them
• TRCA Regulated Area Search: the address search for the Toronto and Region Conservation Authority's regulated area
• TRCA: building a new home: the authority's permit and the municipality's building permit
• 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 Aurora 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 Aurora address.

What we cover, city by city See the sample report