Repurposing an Old Mill Dam with a New Archimedes Screw Turbine (AST) Hydro-Electric Generator Installation

摘要

The Hanover Pond Dam on the Quinnipiac River in Meriden, Connecticut was enhanced to include a small-scale hydro-electric facility featuring Archimedes Screw Turbine technology, the first such application installed within a dam in the United States. The existing 25 foot high dam, initially constructed in the 1850's, and rebuilt in 2005 with the addition of a new fishway, consisted of an earthen embankment, and a 250 foot long concrete spillway to serve a watershed of 95 square miles. The embankment was modified to accept a cast-in-place concrete intake conduit, powerhouse, turbine channel, and tail race. Measures where designed to mitigate risks to the embankment associated with long term seepage, piping erosion and stability. Construction was completed within a 6 month period in 2016/2017 and presented several challenges that were overcome, resulting in a successful project. Difficult conditions included earthwork and concrete work during a New England winter, protection of the adjacent fishway, and poor/saturated existing soil encountered at the downstream side of the dam. During construction, modifications to the downstream embankment were quickly developed to mitigate seepage and poor soil conditions that could be easily implemented under the demanding field conditions without sacrificing the quality of the construction. Constant communication and collaboration with the contractor, owner and FERC regulatory staff allowed the project to continue with minimal delay.