The link between beaver and water quality
When you hear of new development going in next door, usually you think of a new house, or maybe an apartment building? When you live next door to a park, it might surprise you that new houses go up all the time - houses for wildlife that is! Some of the most interesting houses are built by beavers.
Beavers don't know the difference between a nice ornamental crape myrtle in your yard and a Virginia pine standing on park land - and that is often a source of disagreement as to how valuable beaver houses really are. However, U.S.G.S. ecologist Dan Kroes, just completed a three-year study studying exactly that - how valuable are beaver to Fairfax County streams?
His results may surprise you. Dams and lodges (as beaver houses are technically called) are important to water quality. Dams are able to trap sediment (as much as 2 feet) that would otherwise go downstream. Sediment in the water is what makes streams look cloudy or murky. Not only are sediment filled streams unpleasant to look at, they don't allow in sunlight for the aquatic food webs.
Beaver dams and lodges also slow down the speed of water traveling downstream. This is very important in minimizing the erosion of the stream banks that can undercut the bank and fell trees. Slowing down streams has the added benefit of improving our drinking water, increasing the amount of stream life and decreasing the amount of flooding.
Photos by Dan Kroes
© FAIRFAX COUNTY PARK AUTHORITY
Contact Us: General (Office of Public Affairs) | Technical (Web Administrator) | Directed Inquiries (County Agencies)
Phone: County Main Number - 703-FAIRFAX (703-324-7329), TTY 711 | County Phone Listing