Harrington Park, New Jersey (March 23, 2015) – On March 18, 2015, the Low Impact Hydropower Institute (LIHI) received a complete application from Mascoma Hydro Corporation for the Low Impact Certification of the Glen Hydro Project, FERC P-8405, located on the Mascoma River in the town of West Lebanon, Grafton County, New Hampshire.

Project Name Glen Hydro
Owner Mascoma Hydro Corporation
State New Hampshire
Location Located on the Mascoma River, river mile 1.4, in the town of West Lebanon, Grafton County, NH.
Installed Capacity 1.485 MW
Average Annual Generation 6.0 GWh
Facility Type Run-of-river
FERC No. 8405

The Glen Hydro Project consists of: (a) a 175-foot-long, 14-foot-high concrete gravity dam equipped with 3 foot high pneumatic flashboards; (b) a concrete intake structure with trashracks and rake cleaning unit; (c) a 7-acre reservoir with a normal water surface elevation of 413.2 feet National Geodetic Vertical Datum (NGVD) and storage capacity of 60 acre-feet; (d) a 3,100-foot-long, 8-foot diameter buried steel penstock; (e) a powerhouse with three turbine generating units with a combined installed capacity of 1,485 kW; (f) a 300-foot-long 13.2 kV underground transmission line; (g) a 0.48/13.2 kV, 2,000 kVA stepup transformer; and (k) appurtenant facilities. A community park, located about 1,500 feet downstream of the dam and adjacent to the project’s buried penstock, is owned and maintained by the City of Lebanon. The park furnishes parking, picnic tables, volleyball, benches, and children’s playground. The community park appears to satisfy the current level of recreational activity. Occasional bank fishing occurs within the project area.

The New Hampshire Water Resources Board regulates the flow in the Mascoma River at the Project through operation of the upstream outlet of Mascoma Lake. The lakes and ponds in the Mascoma River watershed are operated as a unit of storage of water for power, flood control and recreation. Article 402 of the license requires a minimum flow of 40 cfs into the bypass portion of the Mascoma River immediately downstream of the dam or the inflow to the reservoir whichever is less. A two-foot diameter pipe tees off the penstock immediately downstream of the gate structure to discharges the required minimum flow release of 40 cfs. If the river flow is less than 40 cfs, the Licensee is notified by the State and the discharge pipe is then shutoff.

River flows above the required bypass flow are used for generation. Article 403 requires that the project operate in an instantaneous run-of-river mode for the protection of fish and wildlife resources in the Mascoma River. A pond level sensor at the intake regulates the generator units to comply with the project’s run-of-river mode requirements. The PLC is programmed to start units sequentially as flows become available while maintaining the required 40-cfs minimum flow. All inflow in excess of the total maximum hydraulic capacity of the four turbine generating units, approximately 400 cfs, is passed over the dam.