The Kesslen Dam, alongside the Lafayette Center in downtown Kennebunk, along with Dane Perkins and Twine Mill dams, would be decommissioned under a plan by Kennebunk Light and Power District to surrender the licenses it holds to operate them, Daniel King Photo

KENNEBUNK – Kennebunk Light and Power District trustees will host an online  public meeting Tuesday, Jan. 26 to seek comment following a fall vote to file a plan with the Federal Energy Regulatory Commission to surrender its licenses to operate three hydroelectric dams.

The district plans to decommission the Kesslen, Twine Mill and Dane Perkins dams on the Mousam River, pending FERC approval.

KLPD general manager Todd Shea said the district plans to file for surrender prior to March 31.

The license to operate the dams expires in March 2022.

Power district trustees voted to seek decommissioning because it has “ample access to more reliable and more cost-effective sources of electricity,” according to the plan on its website, and because the dams are no longer economically efficient to maintain or operate.

Shea said he expects the cost of decommissioning to be “south of $100,000.”

Dane Perkins consists of a 12-foot-high, 83-foot-long concrete gravity dam with a 50-foot-long spillway section that has a crest elevation of 81.8 feet at mean sea level.

Twine Mill is a half-mile downstream from the Dane Perkins dam and is an 18-foot-high, 223-foot-long concrete gravity dam with an 81-foot-long spillway section that has a crest elevation of 68.8 feet, mean sea level.

Kesslen is 2 1/2 miles downstream from Twine Mill and is an 18-foot-high, 140-foot-long concrete gravity dam with a 114-foot-long spillway section that has a crest elevation of 42.2 feet, mean sea level.

All have flashboards, generators and other equipment. Under the decommissioning plan, the equipment would be removed, flood gates would be disabled and the area would be secured. The dams would remain in place.

According to the surrender plan prepared by KLPD, there are an estimated 13 dams on the Mousam River. Ten of the dams are located upstream from the KLPD dams – the closest, the 63-foot-high Old Falls dam, is  immediately upstream from Dane Perkins. None of the upstream dams is regulated by the FERC, and, the plan notes, none include fish passages.

There would be no ground disturbance associated with the decommissioning and, therefore, no erosion or other effects on geology and soils, and KLPD said in the plan that it does not anticipate any disturbance to soil, riverbed, water quality, or the original dam facilities. The surrender plan states that the decommissioning would have no effect on fish and aquatic habitat at the dams, and notes that fish habitat in the dams’ reach is minimal. “The continuation of flows through the river will maintain current flow conditions, and there is no expected impact to any existing fish or aquatic life use,” the plan states.

Access by the Kennebunk Fire Department to the river to obtain water for firefighting efforts would remain unchanged following surrender pursuant to the decommissioning.

The surrender plan pointed out that in a nonbinding vote taken on November 2016, 72 percent of Kennebunk voters want the impoundments to remain in place, even after the cessation of hydropower generation and expiration of the license.

If approved, KLPD would permanently cease power generation within 30 days and complete all work by March 31, 2024, pursuant to temporary subsequent licenses, if necessary, to allow the district time to mitigate impacts of decommissioning costs on the rates paid by customers.

KLPD serves 6,979 customers in parts of Kennebunk, Wells, Arundel and Lyman. FERC issued a license to operate the dams to KLPD in 1982.

At least one group, the Mousam and Kennebunk Alliance, has earlier voiced support for dam removal, and members have said that doing so would result in a healthier river system and increase the sport fishery on the river.

Another group, Keep the Kennebunk Dams, has advocated that the dams remain in place, and has previously suggested others might be interested in dam operation. Members have said that removal would impact recreational areas enjoyed by residents and tourists and the possibility of  potentially toxic mud  leaching into the environment.

The surrender plan may be accessed at www.klpd.org.

The online public meeting where trustees will take comment is set for 5 p.m. on Jan, 26, via Zoom. The utility noted that information on how to access the Zoom meeting will be provided on the left-hand sidebar (calendar) of the KLPD website by 5 p.m. on Jan. 25.

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