Comparing Baffle Types in Round Culvert

Hi everyone, 

We hope you are staying safe and well. 

As shared a short while back, we have started using Computation Fluid Dynamics (CFD) to solidify what we already knew about culvert/weir baffles and their fish passage improvement features.

CFD is a powerful engineering tool used to simulate the action of fluids in a structure at a resolution not normally visible to the human eye.

It is well known that fish prefer deep water, complex flows and lower velocity, so it is exciting to see just how much of an impact different types of baffles have on the flow dynamics.

The independent CFD simulation was able to demonstrate the depth, and changes to velocity, with and without baffles installed.

The baffles included in this study were, Type 1 Spoiler Baffles, Type 3 Spoiler Baffles and Flexi-Baffles.

Below is a link to a Glide-show and we hope you find it as interesting as we did!

Contact the Fish Passage Action Team if you want to know more, and perhaps run a simulation on a structure that you are planning to remediate.

CFD Fish Passage Simulation (adobe.com)

Lessons Learnt 8

The NZ Dept Conservation Fish Passage Advisory Group website has a number of Lessons Learnt describing different fish passage remediation projects.

Tim Olley spent over a year researching and putting together this comprehensive report highlighting the effectiveness of flexible baffles in a long, steep culvert.

We are planning to make a PowerPoint and/or video of this report at some point.

Enjoy.

Click here to view Lessons Learnt 8

Fish Passage

Chuck Lobdell and the team at Johnson Creek Watershed OR have recently installed some flexible baffles in the culvert under Highway 26.
The aim is to improve fish passage in all flow particularly for spawning salmon.
The baffles are offset to provide a low-flow swim channel and also extend up the wall of the culvert to assist during higher flows.