Beavers help improve water quality.

Beaver dams:
A natural pollution solution

Beaver dams improve water quality by using physical, chemical, and biological methods in two lines of defense.¹ Initially, pollutants are removed as water entering the pond slows down and again as water is filtered through the dam.² As rainwater flows across the landscape it can pick up a variety of pollutants from urban, industrial, and agricultural sources. Pollutants accumulate in streams where they threaten the health of ecosystems and humans. For instance, the residue left on roads by car tires is responsible for a toxic chemical capable of killing coho salmon.³ Although many human-engineered facilities exist to improve water quality⁴, promoting nature-based solutions can save time, energy, and money while preserving the function and beauty of natural landscapes.⁵

Scientific Citations

1 - Pollock, M. M., Beechie, T. J., Wheaton, J. M., Jordan, C. E., Bouwes, N., Weber, N., ... & Volk, C. (2014). Using Beaver Dams to Restore Incised Stream Ecosystems. BioScience, 64(4), 279-290. https://doi.org/10.1093/biosci/biu036

2 - Rosell, F., Bozser, O., Collen, P., & Parker, H. (2005). Ecological impact of beavers Castor fiber and Castor canadensis and their ability to modify ecosystems. Mammal Review, 35(3‐4), 248-276. https://doi.org/10.1111/j.1365-2907.2005.00067.x

3 - Katherine T. Peter, Zhenyu Tian, Christopher Wu, Peter Lin, Sarah White, Bowen Du, Jenifer K. McIntyre, Nathaniel L. Scholz, and Edward P. Kolodziej. Using High-Resolution Mass Spectrometry to Identify Organic Contaminants Linked to Urban Stormwater Mortality Syndrome in Coho Salmon. Environmental Science & Technology 2018 52 (18), 10317-10327. https://doi.org/10.1021/acs.est.8b03287

4 - Hood, G. A., & Bayley, S. E. (2008). Beaver (Castor canadensis) mitigate the effects of climate on the area of open water in boreal wetlands in western Canada. Biological Conservation, 141(2), 556-567. https://doi.org/10.1016/j.biocon.2007.12.003

5 - Pollock, M. M., & Naiman, R. J. (1998). Hydrologic and geomorphic effects of beaver dams and their influence on fishes. In Ecological Engineering (pp. 139-160). Springer, Dordrecht.