Category Archives: Floodplain Mapping

Updated Floodplain Maps

The RDKB is in the process of updating the floodplain maps. This project is grant funded; as of April 2023 four areas have been updated. Inundation maps (mapping of various flood levels including modelled climate change impacts) has also been mapped and provided in a following post for your information.

As part of this project, the RDKB had a ArcGIS StoryMap produced talking about Flood and Flood Risk in the Boundary Region. Click on the StoryMap Link

The RDKB Floodplain Bylaw will continue to use the old maps until a new Floodplain Bylaw has been adopted and identifies these new maps. Until then, these maps are for your information only. Information about updated the floodplain bylaw can be found at the RDKB Planning page: Floodplain-Bylaw-Update. The reports associated with each map are available for download from the link located above each map. Please go to the page Inundation Maps for additional information on estimated water levels at different return periods.

West Kettle River (Carmi to Beaverdell) download report here

Kettle River (Rock Creek to Midway) download report here

Kettle River (Rural Grand Forks) download report here

Christina Lake, Christina Creek and Kettle River (to US border) download report here

Inundation Maps

Inundation Maps were produced for all areas where floodplain maps were recently updated. Inundation maps show the anticipated water level at different flood return periods with the water volume including the increase we anticipate from impacts tied to climate change. The return periods are: 10 year, 20 year, 50 year, 100 year, 200 year and 500 year. These maps differ from the floodplain maps as the additional 0.6m of freeboard is not shown on these maps. Please direct any questions to the Planning Department ([email protected]) or Watershed Planner ([email protected]).

A download link is provided beside each map. These maps are very large, so many take a long time to download if you are using a slow internet connection. If you are having issues with the download, feel free to contact [email protected] and ask for the information specific to the area you are interested in.

Inundation Events (legend) associated with the maps

Inundation Maps are available for the following areas (the images shown are an example of that area).

  1. West Kettle River (Carmi to Beaverdell): Download link
Click the “download link” above to download the 4 maps associated with this region.

2. Kettle River (Rock Creek to Midway): Download Link

Click the “download link” above to download the 6 maps associated with this region.

3. Kettle River (Carson (US Border) to Cascade Falls): Download Link

Click the “download link” above to download the 7 maps associated with this region.

4. Christina Lake, Christina Creek and Kettle River (to US border): Download Link

Click the “download link” above to download the 8 maps associated with this region.

Area D: Rural GF (2)

The RDKB is in the process of updating the Boundary Region floodplain maps. The floodplain maps for the Kettle River south and west of the City of Grand Forks (2 map sheets) are now ready for public input. We will be holding the public engagement session on:

  • When: Monday, March 6, 2023
  • Where: Meeting room (upstairs) at the Grand Forks Curling Club
  • 7230 21 Street, Grand Forks
  • Time: 4:00-5:00pm: Open house (draft map viewing)
  • 5:00-6:30pm: Presentations
  • 6:30-7:00pm: Questions
Purple represents a draft look at the flood fringe (~200-year flood level), yellow dots represent houses.

To register to attend online please click here or contact [email protected] for a link to the Zoom registration page. To watch a video of the first rural Grand Forks information session, please go to: https://kettleriver.ca/2022/08/rural-gf-study/

Please send any questions to the [email protected]

Unrated Alluvial Fans

In the process of updating the RDKB floodplain maps, fluvial geo-hazards (such as alluvial fans) were also mapped. Four of the mapped alluvial fans were classified (moderate hazard, high hazard and very high hazard); with the remaining alluvial fans left unrated.

The location of the unrated alluvial fans identified through the recent RDKB floodplain mapping project are shown below. If you have any questions, please reach out to [email protected].

Legend:

  • Pink polygon: unrated Alluvial Fans
  • Yellow dots: Houses based on the RDKB address layer

Area E (West Boundary)

West Kettle River: Carmi to Beaverdell

Kettle River: Rock Creek to Midway

Area D (Rural Grand Forks)

Kettle River: Carson to Cascade Falls (outside City limits)

Area C (Christina Lake)

Christina Lake

Christina Creek

Area C: Floodplain Maps

Recording from the November 22nd meeting. For a comment or input to be included in the official mapping review, it must be submitted by Tuesday November 29th. Comments can be emailed to [email protected]

DRAFT Area C floodplain and alluvial fan maps can be downloaded from the two links below:

The draft maps have been removed from the website, as they are now being processed into their final version. Our hope is to have the final version available to the public by summer 2023.

The Public Engagement meeting was held at the Christina Lake Community Hall (90 Park Road, Christina Lake), on Tuesday, November 22, 2022. Meeting layout was:

  • 4:00-5:00 Open House
  • 5:00-7:00 Presentations: Northwest Hydraulic Consultants (Engineers) and RDKB staff: Donna Dean (Planning and Development), Freya Phillips (Senior Energy Specialist) and Mark Stevens (Emergency Management)
  • 7:00-8:00pm Additional time for questions

This was both an in-person and online meeting. The online option was through Zoom (recording shown above).

The current (1991) floodplain mapping extent (200yr) for Area C

Floodplain maps are expected to be updated every 10-20 years, or after any major event. Following the high water event in 2018, the RDKB has been aware that they needed to update the floodplain mapping throughout the Boundary Region. In 2020 a flood and geohazard assessment was completed by Ebbwater (report available at https://rdkb.com/Environment/Watershed-Planning) which identified priority areas for assessments. In 2021, the RDKB received approximately $800,000 to start updating the Boundary flood and geohazard maps. As the cost for these flood and geohazard mapping is covered through grants, not all of the Boundary was able to be covered this year. The areas prioritized included:

  • Area C: Christina Lake, Christina Creek and Kettle River
  • Area D: Kettle River (east of the municipality of Grand Forks)
  • Area D: Kettle River (south and west of municipality of Grand Forks)
  • Area E: West Kettle River: Carmi to Beaverdell
  • Area E: Kettle River: Rock Creek to Midway

Mapping still needing to be completed include:

  • Area D: Granby River (north of Municipality of Grand Forks)
  • Area E: Kettle River: Rock Creek to Fiva Road
  • Area E: West Kettle River: mouth with the Kettle River past Rhone

For permitting and bylaw requirements, the floodplain maps to be referred too are the ones identified in the RDKB Floodplain Bylaws. These new maps are only to be used for permitting purposes after the RDKB Floodplain Bylaw has been updated, endorsed by the RDKB Board and updated on the RDKB website.

The draft Area C maps will be available for download on Tuesday November 22 until Tuesday November 29, 2022.