Dam Seals in North America
or The Little Dutch Boy of Large Concrete Dams
CGLLC has been involved with installing in-situ dam seals with Structural Preservation Systems, Inc. Hanover, MD, for 20 years. Work has been performed for Tennessee Valley Authority, New Brunswick Power, Canada; US Army Corps of Engineers; and Bureau of Reclamation.
These seals are installed for two primary reasons:
1. Retrofit a dam for failed waterstops as is the case at Folsom Dam (Bureau of Reclamation), CA; Harry S. Truman Dam (USACE), MO; Apalachia Dam (TVA), TN; Big Bend, SD; and Bagnell Dam, MO.
2. For new expansion joints in dams experiencing alkali-aggregate reaction expansion problems. In these situations (TVA and Mactaquac) slots are cut into the dam to relieve internal pressure and seals are installed to control water infiltration. This work has been performed at numerous TVA dams (Hiawassee, Chickamauga, Fontana;) and at Mactaquac Dam (NB Power), Canada.
The latest project, over the past two years, were the replacement of 5 failed waterstops (by a different contractor) and two new installations of seals at USACE Big Bend Dam, Ft. Thompson, SD
Largest diameter seal installed is 14 inch at Mactaquac Generating Station, Fredericton, NB
Longest seal is in Folsom Dam at 198 feet deep
This technical paper was presented at the 2001 Canadian Dam Association Conference:
Before and After Video: Click on the picture
No endorsement by TVA is intended or implied hereby
Click on the photos to enlarge: