Awesome Free Culvert Baffle Design Calculator

February 3, 2026

Hi everyone,

Baffles have proven a very effective way for providing fish passage in culverts.

We’ve been hard at work over the past few months developing an interactive culvert baffle design calculator.

We know culvert design can be a tricky subject to get your head around, and we were worried it could be putting some people off. Having seen a groundswell of culverts being designed to improve fish passage, we saw the need for a more standardised approach while still taking into account individual site characteristics.

We’re excited to announce a new resource for fish passage practitioners – the Culvert Baffle Design Tool, created by the Fish Passage Action Team and kindly hosted by ATS Environmental.
­ Click here to try it now – it’s free! ­ This free online tool takes the guesswork out of baffle design for new & exisitng culverts. Enter your culvert characteristics and the tool will automatically generate:

  • A set of schematic drawings showing the baffle configuration
  • A list of materials required, including baffle sizes, types, and fixings for installation

Any feedback would be most helpful.

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