Wildlife Friendly Culverts

Sketch of a circular fish friendly culvert and wildlife barrier. The second sketch has an arched fish/wildlife friendly culvert.




Windlife accessing habitat can be increased greatly with little added cost. Methods listed below will do this. Culverts have been installed for hundreds of years that have removed habitat for 35 to 40 different wildlife species. There is a solution for this concern but only a few States in the US are incorporating the solution. Three main reasons many States do not install wildlife friendly culverts and resolutions.

1.      Arched wildlife friendly culverts are very costly.

         Studies show a 4' circular culvert installation is about $5,000.00 and an replacement arched wildlife friendly cost is $50,000.00

2.      Replacement arched culverts may allow too much flow with house flooding downstream

3.      Huge culverts that allow large animal crossing of roads are very costly

Resolutions:Sketch SK-1 has a design where a standard circular culvert can be converted to a wildlife friendly culvert for the same cost except concrete footing and support will need to be added. This culvert should perform just as good as an arched culvert removing most of the added cost of item 1. Because replacement circular culverts have the same area as old culverts seems like the new culvert flow resistance will not be more than the old culvert and there should not be much concern of adding flooding conditions downstream removing most of the concern for item 2. A high percentage of biomass of areas is composed mostly of small animals and installing wildlife friendly culverts only for these animals will minimize cost in item 3. This is only an idea and a review by design and engineering would need to be performed to determine if this is true.


Example link to circular pipe culverts with two halves. 

Armtec Nestable Corrugated Steel Pipe 




Webster definition of Biomass: ...1 : the amount of living matter (as in a unit area or volume of habitat)2 : plant materials and animal waste used especially as a source of fuel...








For detailed information on wildlife friendly culverts please visit the below link. Also for actual pictures of barrier culverts and wildlife friendly culverts please view links.

Wildlife friendly culverts  




 ..Smaller animals give the greatest impact for the biomass of an area. Being in the lower food chain they feed all larger animals. Fish friendly culverts impact small animals and weak swimmers with weak swimmers drastically reduced over hundreds of years of barrier culverts and fish friendly culverts. Presently, I believe, the Nation is missing a large percentage of biomass to feed animals in the food chain but new wildlife friendly culverts for smaller animals would only stop future decimation of the food chain biomass...

Please contact your elected representatives listed below and share your thoughts for the need of wildlife friendly culverts. Note: This is not only a Louisiana concern and only a few States have Wildlife Friendly Culvert design. All States need to publish this design. I believe contacting your Federal Representatives would help make a National committment to Wildlife Friendly Culverts.

LouisianaRepresentative;Natural Resources and Environment, Chairman, Gordon E. Dove

United States:Representative;Committee On Natural Resources