Drainage work under way at Garrison Dam

RIVERDALE – A portion of the Garrison Dam has been undergoing construction this summer to replace a drainage system.

Project manager Todd Lindquist with the Corps in Riverdale said the drainage system on the west abutment of the dam is being replaced because the system in place was losing effectiveness. Earthen dams have some natural seepage,and drainage systems are installed to manage that water.

The project has included drilling a series of wells and pumping water down those wells to create a dry area for installing the drain pipe. The dewatering is necessary due to the reservoir’s pool elevation, which affects groundwater. The reservoir is at its normal operating level, Lindquist said.

The work is expected to be completed this year.