This post is the second in a series that describes the state of flood hazard mapping in British Columbia. If this piques your interest you can also check out:
Last month, we reported that in general, the floodplain maps that are relied upon to minimize the impact of flooding in the province are quite simply old. This month, we expand on this a little, by providing a map. We have used the simple methodology described previously to catalogue map information, but have now attached the data to a GIS shape layer (thanks to the lovely QGIS).
The map below shows the location and age of provincially designated flood maps in BC, where the oldest maps are shown as a dark red and the younger (this is most definitely a relative term) maps are yellow.
One of the first things that strikes me about the image is that the coverage makes sense; we have a lot of maps in the southern half of the province, and fewer in the north. We also have a lot more people in the southern half of the province. (Check out this post for more information on populations in the floodplains). Of course, the big gap in mapping coverage is the Lower Fraser Valley – again a story for another day. But in the meantime, the good news is that no one region is worse off than another. This creates an opportunity for each regional district or municipality to chip away at the problem rather than facing an urgent need to update all their maps at once.
The Ebbwater BC Flood Map Project
We’ve just started our gap analysis and thought project on flood maps in BC and have a whole host of other analyses that we want to complete. We’d love to hear from you if you have a good idea on how to use or present the data, we’d also love to hear from you if you know of or have a map that’s not in our database – we’ve started our project using the Province of BC dataset, but know there are other maps (newer and better ones!) out there and would like to include them. You can contact us by email: BCFloodMapProject@ebbwater.ca or feel free to call or drop by our office.