The Federal Energy Regulatory Commission’s Office of Energy Projects on Jan. 16 issued an environmental assessment report on PayneBridge LLC’s application for an original license to construct and operate the 4-MW Williams Dam Water Power Project.
The project would be located on the East Fork White River in Lawrence County, Ind., near the town of Williams, at an existing dam owned and operated by the Indiana Department of Natural Resources.
In December 2012, PayneBridge, a subsidiary of Boston-based hydro developer Free Flow Power, filed an application for an original license with the commission for this project. The existing Williams Dam and powerhouse were constructed in 1910 by the Bedford Power Co. The facility was owned and operated by a series of utilities until it was decommissioned in the 1950s.
Williams Dam consists of a 21.3-foot-high by 294-foot-long hollow (Ambursen type) concrete dam with a full length uncontrolled spillway at a permanent crest elevation of 472.2 feet North American Vertical Datum of 1988 (NAVD 88). The dam impounds the East Fork White River to form a 553-acre impoundment with a storage capacity of 5,720 acre-feet.
Integral with the dam is an abandoned 107-foot-long by 52‑foot‑wide concrete powerhouse substructure that contains an unknown amount of what is considered to be inoperable generating equipment. The intake gates at the powerhouse are no longer operable and bulkheads have been bolted to the intake divide walls to maintain the reservoir level in the impoundment. Currently, the majority of the inflow at Williams Dam passes uncontrolled over the Williams Dam spillway. Leakage around and through the existing bulkhead gates causes a small, unknown quantity of water to pass through the powerhouse.
This new project would use existing features, including the powerhouse substructure, which would be utilized in its basic existing form. The project would include four vertical Kaplan turbines that would be coupled to a 1-MW generator unit for a total installed capacity of 4 MW. Power from the generators would be conveyed via a new underground 4.16-kV feeder line to a new 40- by 40-foot substation that would be located west of the proposed project. A new 265-foot-long, three-phase 12.5 kV, overhead transmission line would also be constructed from the project substation to local utility power lines.
The project would operate in an instantaneous run-of-river mode, whereby outflow from the project reservoir would equal inflow, and the water surface elevation of the impoundment would be maintained at the existing normal pool elevation (crest of the dam spillway) or above. The estimated average annual generation would be 17,849 megawatt-hours (MWh).