Bioengineering Bank Stabilization

Fernald stabilized a stretch of eroding banks along Paddys Run Stream  (6690D-99).

During construction of the Fernald site and waste storage areas in the early 1950s, alterations to site drainage patterns and straightening the Paddys Run Stream channel resulted in extensive stream bank erosion. In some places, Paddys Run banks were cut as deep as 50 feet into glacial overburden.  This reduced the stream’s floodplain and riparian buffer, which in turn compounded the effects of erosion downstream and threatened a sediment basin at Fernald’s Southern Waste Units. 

To stabilize the eroding banks, Fernald completed a bioengineering project in 1998 at the Southern Waste Units.  Bioengineering is a technical discipline that merges engineering concepts with biological knowledge to design solutions to erosion and land stability problems.  Based on a design by John Munro Ecological Services, Inc., and Parsons Infrastructure and Technology Inc., Fernald workers regraded the eroded slopes to restore the gently sloping floodplain, and placed coir (coconut fiber) logs at the toe of the banks to provide stability. They then placed coir fabric along the length of the regraded bank, seeded the soil under the matting with a native prairie grass mixture, and inserted willow cuttings through the coir fabric into the ground to stake the fabric in place. 

These bioengineering techniques allow the stream banks to accommodate its intermittent high flow without eroding the banks.  As the coir fabric decomposes, the native plants continue to grow and spread to offer natural bank stabilization.

For More Information
Contact Sue Walpole, S. M. Stoller, at 513-648-4026, e-mail: Sue.Walpole@lm.doe.gov .