Fifth Avenue Lowhead Dam Removal on Olentangy River

The City of Columbus wants to remove a lowhead dam under 5th Avenue on the Olentangy River and the U.S. Army Corps of Engineers is recommending removing the dam to improve water quality. Back in 2002, the City of Columbus asked the Corps to study removal or modification of the 5th Avenue Dam under its authority to improve an aquatic ecosystem. Aside from the hazard to boaters, lowhead dams cause sediment to build up and can reduce the oxygen level in the water. Removing the dam would open the river to boaters from Dodridge Street to Downtown.

The 5th Avenue dam was built decades ago to provide water for an Ohio State University power plant. The decision to remove the dam is up to Columbus city officials. The city would provide 35% the $1.8 million cost of removing the dam; the rest of the money would come from federal monies earmarked for water quality improvement.

The Corps is now in the process of conducting tests on the sediments and materials that would be disturbed by the removal. Those results should be reported in late spring. Plans for the project would take about six months to complete, and barring any complications, removal would begin in late spring 2009. It is estimated that the project would take 6 months to complete.

The City of Columbus says the benefits of removing the dam on the Olentangy are outweighed by the cost. Lowhead dams are dangerous because anyone who falls in can become stuck and drown in the circular roil at the base of the dam. A draft report from the Corps dated December 2007 found dam removal would restore the river’s natural flow and habitat conditions and the Corps concluded water quality would improve between the dam and Dodridge Street to the north.

The Corps committed funds for the project based on that draft report, and city staff was preparing to take the initial steps toward the design phase of the project, when federal monies were cut.

At the time of this publication, the Corps states that there is a possibility of add-on funding for this project. Of $29 million earmarked for water quality projects in the 2008 federal budget, $9 million has not yet been allocated. Sixty-one projects are vying for those remaining funds.

There are no plans to remove the five other lowhead dams on the Olentangy because they cover sanitary sewer lines, which a 2005 study deemed too expensive to move.