Brian Conklin

Degree Name

Master of Science (MS)

Semester of Degree Completion


Thesis Director

Eric K. Bollinger


Dam construction by beavers creates wetlands which have the potential to improve water quality, especially in areas near urban centers. However, beaver dams may also cause flooding problems which can result in the removal of the beaver(s) and the destruction of their dam. A further understanding of how beaver-created wetlands affect water quality will provide additional data which can be utilized in beaver management decisions.

In this study, 41 chemical parameters were examined from water taken above and below beaver-created wetlands that existed in DuPage County, Illinois between May and September 1991. This study was designed to examine the effects that these urban populations of beaver have on the water quality of the associated streams and rivers. Results of this study suggest a significant reduction in dissolved sulphate, solids, calcium, magnesium, barium, boron, sodium, chloride, bromide, fluoride, strontium, and nitrate. Increases in arsenic and manganese in water flowing out of beaver-created wetlands were also observed.