Effect of beaver dams on hyporheos patterns.

Abstract

Temperature profiles were taken for the hyporheos of a northern Michigan river around two beaver dams. Measurements were made using a 200 cm long stainless steel temperature probe, for 100 cm into the substrata. Measurements were taking during the summer with the dam in place, and again after removal of the dam. The beaver dams were active, and created a pool by the large dam that had a maximum depth of 146 cm. This pool created a drawdown of stream water, which lowered the discharge of groundwater further downstream. Upwelling of cooler water was visible downstream of the beaver dams, and recovery of the groundwater to the water-sediment interface occurred after the removal of the dams. Velocity of the hyporheos water was measured using mini-piezometers. The results obtained provide an understanding of the water patterns, and has the potential of being used to understand the hydrology around a dam.