Floodplain mapping

Last updated on September 1, 2023

Floodplain maps identify areas that experience periodic flooding from nearby rivers, lakes, streams and the sea and provide information on the spatial distribution of flood construction levels.

Floodplain maps show the location of the normal channel of a water course, surrounding features or developments, ground elevation contours, flood levels and floodplain limits—the elevation and horizontal extent of the high water marks of a 200-year flood.

Floodplain maps

Floodplain maps show areas of B.C. that are highly susceptible to flooding. Flooding may still occur outside of these floodplain areas.

Coastal floodplain maps

Coastal floodplain mapping identifies coastal flood hazards, such as sea level rise, and provides guidance for land use planning.

Emergency planning floodplain maps

Floodplain maps of the extent of the Fraser River floodplain are available for the purposes of flood emergency planning.

Use and limitations of floodplain maps

A floodplain map delineates the area that can be expected to flood, on average, once every 200 years. This is called the 200-year flood. A 200-year flood can occur at any time in any given year, exceed the indicated flood level, and portions of the floodplain can flood more frequently.

Floodplain maps show minimum elevations for floodproofing. Minimum floodproofing requirements can then be incorporated into building bylaws, subdivision approvals, and local government planning and regulations.

Professional assistance and detailed engineering analysis may be required to address any of the above considerations.

Flood levels indicated on the maps are the minimum recommended elevations for floodproofing requirements.

Sea level rise

Information on a range of tools that can be used as part of a sea level rise adaptation strategy: