Based on months of study, Upper Peninsula Power Co. has concluded it must amend its Federal Energy Regulatory Commission license for the 11.2-MW Dead River hydroelectric project to make rebuilding the failed Silver Lake Dam feasible.
The Dead River project (No. 10855) has two powerhouses located below the Silver Lake storage basin, whose dam failed in May 2003. FERC found a fuse plug foundation and emergency spillway channel were inadequate and had eroded more than expected.
UPPCO, a subsidiary of WPS Resources Corp., originally anticipated making a decision in May on whether to rebuild the dam. However it announced in September that the number of issues to be resolved made that target date unrealistic.
UPPCO first looked at rebuilding Silver Lake under the current license, scheduled to expire in 2042, but it said that choice is not economical because it requires constructing an additional dike and increasing spillway length. The utility then began reviewing options including a lower operating reservoir level and different-sized spillways, looking for a plan that would make rebuilding Silver Lake more economical than abandoning it. All the options would require a license amendment, UPPCO said.
“The process is becoming increasingly more complicated,” UPPCO General Manager Keith Moyle said. ï¿½We’re balancing the needs of multiple stakeholders, and those needs occasionally conflict with each other. From a fiscal perspective, the company needs to balance the cost of rebuilding with the benefits it would provide. We also need to balance environmental concerns, such as minimum water levels, with recreational interests.ï¿½
From months of analyzing different approaches, the utility concluded it must amend its FERC license and Clean Water Act Section 401 water quality certification from the Michigan Department of Environmental Quality to make the project feasible. Moyle said the license amendment application would address operating issues that would help increase efficiencies of the project.
To make rebuilding economically feasible, UPPCO said resource agencies must come to agreement with the utility on the proposed amendment, which UPPCO is in the process of finalizing.
The resource agencies include the Michigan departments of
Natural Resources and Environmental Quality, and the U.S. Fish and Wildlife Service, as well as the Keweenaw Bay Indian Community. If everything falls into place, UPPCO said it would like to begin construction in 2007 and finish in 2008.
“We remain optimistic that we will rebuild, but it’s a big decision,” Moyle said. “To meet the needs of all the stakeholders — our customers, shareholders, resource agencies, and the community — we have to find a way to keep the Dead River generation system economical for UPPCO with the least impact on the environment and recreational use.”