Duke Energy Carolinas LLC said it plans to build a new powerhouse to replace 18-MW Bridgewater powerhouse as part of a seismic remediation project planned for Linville Dam in North Carolina and South Carolina.
Remediation of Linville Dam requires removal of Bridgewater powerhouse and construction of a 26.4-MW replacement powerhouse before dam remediation can begin. Linville is one of three large earth dams in the Bridgewater development of the 814-MW Catawba-Wateree hydroelectric project (No. 2232).
Remediation calls for a compacted earthfill stability berm to be constructed on the downstream portion of the 160-foot-tall, 1,325-foot-long embankment dam. The new powerhouse would be built outside the footprint of the dam remediation project, about 200 feet downstream of the existing powerhouse at the toe of the dam.
Duke announced the signing of a relicensing agreement for the Catawba-Wateree project in August 2006. (HNN 8/17/06) Modifications to allow the flow releases to meet relicensing requirements were discussed over a three-year period among participants in the relicensing process.
Duke settled on building a new powerhouse after considering whether to replace the existing 18-MW powerhouse with a new powerhouse or to install a valve system as a means of releasing flows from the reservoir.
Duke’s request to replace the powerhouse is pending before the Federal Energy Regulatory Commission. If the new powerhouse proves infeasible, Duke would implement the system of large valves at the same location as an alternative means of releasing flows.