Is a London address in a regulated flood area, and whose map says so?
The Upper Thames River Conservation Authority's regulated area maps, and the Kettle Creek Conservation Authority's map, under Ontario Regulation 41/24.
Sources checked October 28, 2026
Conservation authorities in 2027
Upper Thames River authorityjoinsWestern Lake Erie Regional Conservation Authority
Kettle Creek authorityjoinsEastern Lake Erie Regional Conservation Authority
On 1 February 2027 or a later date set by regulation, under the Conservation Authorities Act as amended in 2026.
- The recordFlood plain and regulated area
- Where to read itUTRCA regulated area maps; UTRCA regulated areas: frequently asked questions and 7 more
- In the full reportWith the address's other records
What the record shows
The Upper Thames River Conservation Authority regulates development in or near natural hazards under the Conservation Authorities Act and Ontario Regulation 41/24, and publishes its regulated area maps online at maps.thamesriver.on.ca. Its regulatory flood is the observed 1937 flood on the Thames, estimated at a 1:250-year flood, and the regulated area takes in flood plains, river and stream valleys, watercourses, and wetlands with 30 metres around them. On October 6, 2026 its board approved map updates for the South Thames study area, down to London's eastern limits, and the Delaware study area, from London's western limits, to be added to the online map within 30 days. Homeowners, buyers and the lawyers or agents acting for them can ask the authority for a formal property inquiry, for a fee.
The City of London is also a member municipality of the Kettle Creek Conservation Authority, whose own map shows its regulated areas and notes that a property may cross the boundary of two authorities. A regulated-area result governs permits for building, filling and work near water; it is not a forecast that a home will flood. Under the Conservation Authorities Act as amended in 2026, the Upper Thames River authority is to join the Western Lake Erie Regional Conservation Authority, and the Kettle Creek authority the Eastern Lake Erie Regional Conservation Authority, on 1 February 2027 or a later date set by regulation.
Where to read it yourself
- UTRCA regulated area maps: the Upper Thames River Conservation Authority's maps, layers and October 2026 updates
- UTRCA regulated areas: frequently asked questions: what is regulated, the 1937 flood standard and property inquiries
- KCCA Map Your Property: the Kettle Creek Conservation Authority's regulated area map
- KCCA governance: lists the City of London among the authority's member municipalities
- Western Lake Erie Regional Conservation Authority: the authority's page on the merger planned for 1 February 2027
- KCCA conservation authority amalgamation: the Kettle Creek authority's page on the merger
- 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
What OfferDue covers in London
Conservation-authority regulated-area and flood plain checks are not currently included in our reports, so for a London home the authority's own maps is 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 London address.
Public-record information, not legal, financial, insurance or inspection advice. Records change and can be incomplete, and this page describes the records, not any particular home. What we cover, city by city.