The Gorge Dam is one of the largest remaining unresolved water quality problems for the Cuyahoga River. In addition to restoring water quality, removing the dam and the sediment behind it will restore the original grandeur of the Gorge, creating a vibrant future for the river, its watershed and its people. That future will provide clean water, natural beauty, recreational opportunities and economic development for all to enjoy.
Dams have significant water quality implications. In addition to being a physical barrier to fish passage, dams negatively affect the dissolved oxygen, flow and temperature of the river. They also reduce habitat, trap and concentrate sediments and toxins and alter the food web. On the Cuyahoga River, dams have been shown to adversely impact aquatic life. They alter the natural river aquatic communities, which are restored after the dam is removed.
Before the dam can be deconstructed, nearly one million cubic yards of sediment must be removed from behind it. The sediment has been collecting for 100 years and contains pollutants consistent with the area’s industrial past.
A mechanical dredge system consisting of a clamshell bucket, crane and a scow barge will troll the reservoir, slowly removing sediment scoop by scoop. This work will likely be completed over two construction seasons. Each full scow barge will then be unloaded at the staging area, where it will be screened to remove any large debris.
The still-wet sediment will then be pumped through a temporary pipeline under the Front Street Bridge and then alongside Highbridge Trail. It will continue under the High-Level Bridge at North Main Street to the Chuckery Area of Cascade Valley Metro Park, about two miles from the dam.
The Chuckery Area is historically a dumping site and will be utilized as the permanent disposal area for the contaminated sediment. To make room to store the sediment and concrete mixture, trees must be removed from a portion of the Chuckery Area.
The sediment is mixed with concrete in the pipeline to form a more solid material that can be contoured before it is fully stabilized. This is an innovative and safe approach that has been used at sites across the country. The disposal area is designed to ensure permanent stabilization of the sediment mounds, minimize impacts to buried utilities, and appropriately manage stormwater.
After final grading is complete, the sediment mounds will be capped with soil and the area will be planted with a native mix of trees and vegetation, and contoured to look as natural as possible. The final conditions will result in a biodiverse habitat that will complement the natural beauty of the Cascade Valley Metro Park.