1

I am currently working on an assignment where I need to model flood risk areas. Firstly I was asked to identify potential flood risk zones based on the following criteria:

  1. identify areas that I would consider to have steep slopes. I think I have completed this task. I used the Slope tool here.

  2. Identify a 20 year flood zone and base this on an estimated distance from rivers. Then repeat the task for a 100 year flood return. A guide value would be not to go beyond 2 kilometers for the 100 year and less for the 20 year. I have no idea how to even start this. I have googled different things have come up with extensions that can be used but we never went over any such extensions in the college practicals.

Improve this question
1

1 Answer 1

Reset to default
1

I would typically not base a flood zone on distance from the river, but instead on elevation (a very steep hill right next to a river is very low flood risk, for example). However, if you don't have elevation data, I guess distance can be a reasonable estimate.

Measuring distance from a river can be accomplished with the Buffer tool. Create a buffer of the size you think valid for a 20 year flood distance, and for a 100 year flood distance. (What that distance might be, I'd hesitate to even guess!)

Improve this answer
2
  • Thank you, I never even thought of the buffer tool. I really appreciate your help here :)
    – user43548
    Commented Jan 3, 2015 at 18:32
  • Hope it gives you the results you need! :)
    – Erica
    Commented Jan 3, 2015 at 19:46

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.