Fort Halifax - FERC #2552. Fort Halifax is a 1.5 MW project owned and operated by Central Maine Power Co. (CMP) located in Kennebec County on the Sebasticook River, 1,400 ft. upstream of the confluence with the Kennebec River. The dam and powerhouse are located in the Town of Winslow and the impoundment extends 5.2 miles upstream into the Town of Benton. The impoundment has a surface area of approximately 417 acres at full pond level. The project consists of a concrete Ambursen dam with a maximum height of 29 ft. and powerhouse which houses two generating units rated at 750 KW each. The water quality classification for the Ft. Halifax Dam impoundment and tailrace areas is Class C. CMP is currently proposing to enhance water quality by monitoring dissolved oxygen, and flushing when a level of 5 ppm is reached. The applicant's proposal involves no alteration of existing energy capacity but initiates and sustains several measures for protecting and enhancing environmental resources including:
• Providing a minimum flow release from the project of 150 cfs or inflow, whichever is less, for a period of April through November annually, in order to provide a zone of passage for migrating anadromous fish;
• Limiting normal impoundment fluctuations during daily cycling operations to a maximum of 2.5 feet from full pond (to elevation 49.0 feet MSL), in order to protect fish and wildlife resources in the impoundment;
• Installing permanent downstream and upstream fish passage facilities at the project by December 31, 1993 and May 1, 1999, respectively, in accordance with the Agreement between the State of Maine and the Kennebec Hydro Developers Group (KHDG), in order to restore anadromous fish to the river above the dam;
• Maintaining and improving as necessary existing recreational facilities (a carry-in boat access site on the project impoundment and a downstream fishing access trail) and providing new recreational facilities (a trailored boat launching facility serving the project impoundment and a marked canoe portage trail around the project dam) in order to protect and enhance public recreational access to and use of project waters.
During second stage consultation with the State agencies, points of disagreement between CMP and the agencies were identified. One unresolved area involves minimum flows. Based on the results of the IF&W study, IF&W would prefer a minimum flow release of 400 cfs to provide optimal habitat for both life stages of brown trout, the species of concern for that agency's management program. IF&W concurs with the DMR and the USFWS recommendation for operation of the project in a run of river mode during upstream anadromous migration period (May 1 - June 30). The 400 cfs minimum flow release would apply for the rest of the year when the project was operated in a peaking mode.
DMR recommends adoption of a slightly lower minimum flow of 350 cfs, instantaneous minimum flow or inflow, whichever is less, from mid-July through October.