Mousam River Dams FAQ

Keslem Dam Mousam River
Dam 3
Dams pic1
Kesslen dam

The Mousam River is the only major river system in Maine completely lacking in fish passage. The Mousam’s watershed contains 349 miles of river and streams and drains a total area of about 117 square miles of southern Maine, in the towns of Acton, Shapleigh, Waterboro, Sanford, Alfred, Lyman, and Kennebunk. There are 15 known dams in the Mousam watershed, including 11 on the main stem between the outlet of Mousam Lake in Shapleigh and the head-of-tide in Kennebunk, a stretch of river only 24 miles long.

Only 1% of the river is still connected to the ocean and accessible to important species like American shad, Atlantic salmon, alewives and blueback herring. Because of dams, all of the river’s native anadromous fish species are confined to a very small stretch of spawning habitat below the first dam in downtown Kennebunk. It’s time to change that.


The lowermost three dams are owned by the Kennebunk Light and Power District (KLPD). These dams are up for relicensing by the Federal Energy Regulatory Commission (FERC). KLPD Trustees have indicated that they would like to make a decision about whether to seek a new license for the dams by the Spring of 2016.

The Mousam Kennebunk Rivers Alliance here highlight some critical findings from the March 2016 Dam Alternatives Report by Wright- Pierce commissioned by KLPD that strongly support our longstanding position that Alternative #4, dam removal, is the most environmentally beneficial and least expensive option.

Q: How much will it cost to install and maintain effective fish passage compared to removing the three dams?

A: Fish passage and relicensing all three dams will cost $8.8-$11.7 million in 2016 dollars. Complete dam removal will cost only $2.3 million and 50% or more of these costs can be covered through grants.  Factoring in inflation at 2%/year, the costs become $13.3-$16.9 million (according to the WP report) for relicensing versus $2.5 million for dam removal.


Q: How would removing the dams affect utility rates?

A: Each of the 4 alternatives described in the report will be an expense that could raise rates; dam removal will have the lowest impact on rates and offer the longest term savings.


Q: How effective is dam removal in restoring fish populations compared to fish passage?

A: Dam removal is far more effective than constructed fish passage, and avoids ongoing maintenance and operating  costs.


Q: What if KLPD installs fish passage facilities but they don’t work as well as required under relicensing requirements?

A: Constructed fish passage on a FERC project is required to work effectively, if it doesn’t KLPD has to keep investing in new construction until it meets FERC’s required targets for a variety of  species.


Q: How would the four alternatives in the report differ in their impact on water quality?

A: Testing shows that water quality in the impoundments is poor. Only dam removal is assured to improve water quality, additional investment is required to meet Clean Water Act standards if the dams remain.


Q: How would dam removal impact wildlife around the impoundments?

A: We will see a marked increase in the variety of species and abundance of wildlife with a free flowing river and intact natural system.


Q: How would dam removal affect property values?

A: Studies by top-notch economists in Maine, Wisconsin, Oregon, and elsewhere have demonstrated that property values increase when unnatural impoundments are restored to free flowing rivers.  Additionally, the risk of flooding is dramatically reduced, so homes are safer, and flood insurance costs could be reduced.


Q: Will dam removal have a positive effect on tourism?

A: You bet it will! What is good for the environment is good for business. Birders, anglers, paddlers and other tourists will be drawn to the river.


Q: Does dam removal pose a risk of contaminating the river and abutting land?

A: KLPD had Wright Pierce conduct an initial sediment sampling, and no significant problems were found.  They stated that the funds that had been included in their report for possible sediment removal should be sufficient. 


Q: Would removing the dams have any effect on sewer or water systems?

A: The report and utilities say  NO.


Q: Why would we want to reduce renewable energy production by removing the dams?

A: Hydropower is not always “green” power. KLPD generates only 1.2% of their electric supply from their three dams, yet the dams block 100% of migratory species in the river. It is just a poor business and environmental choice to keep them when other efficient options, like solar, are available.


Q: Should the town consider taking ownership of Kesslen Dam if KLPD does not want it anymore?

A: No! The town’s taxpayers should avoid taking on the liability and significant annual expenses of these dams.


Q: Is the Wright Pierce Report "HYDROPOWER FACILITY ALTERNATIVES ASSESSMENT STUDY" that KLPD commissioned available to the Public?

A: Yes the Wright Pierce report is available at KLPD's website or Click here 

KLPD shows a $336,023 loss since 2010 operating the 3 hydropower dams on the Mousam River.

Relicensing and continued operations will cost $16.9m