The key to restoring the health of our waterways is the removal of man-made barriers, such as aging, obsolete dams, that currently impound water flow causing higher water temperatures, lower oxygen levels, while encouraging the growth of invasive plant species. All of these factors degrade aquatic habitat. Additionally, dams present major obstacles to the up and downstream movement of aquatic wildlife, such as fish and turtles. These dams present significant repair and maintenance expenses for local communities, and, with the increase in extreme weather events, they present a threat to human health from flooding or breach. With the removal of a dam, more natural processes can be restored to the river system. The reconnection of free flowing water and movement of sediment will improve water quality and aquatic habitat, as well as allow for free movement of wildlife.
The NRWA is excited to partner with local communities to assist with dam removal projects, from identifying priority sites, to applying for grant funding to support removal, to working with partners to manage ecological restoration of the stream and site post-removal. Such partnership led to the successful removal of the Whitney Pond Dam on the Whitman River in Ashburnham and Burke’s Pond Dam on Sucker Brook in Pepperell. Both projects involved partnership between state agencies, municipal officials, engineering and construction firms, local non-profit partners, and the NRWA.
View Whitney Pond Dam removal video.
Read a detailed account of the Whitney Pond Dam removal and ecological restoration project.
Photos left: Top, Whitney Pond Dam downstream wall. Bottom, Whitman River restoration begins post removal.
With the removal of these structures, ecological restoration is now underway with ongoing monitoring of water quality and wildlife activity. NRWA is logging water temperatures and dissolved oxygen levels at the Whitman River site to monitor the health of the river for aquatic species. Both the Whitman River and Sucker Brook are coldwater habitat capable of supporting native trout. In their reconnected, free-flowing state, the fish populations have a more resilient habitat as we face rising temperatures.
Restoration also involves the planting of native plant species to secure banks, create shade for the streams, and provide healthy riparian habitat for wildlife. Extensive planting of native grasses, sedges, shrubs, and trees has already been completed in Ashburnham, and the plantings will be monitored for a number of years to ensure robust establishment.
An additional benefit at the Whitman River site was the creation of a walking trail at the site, with benches and interpretive signs that share the history of the mill that was once at the site as well as the story of the dam removal and restoration. Dam removal projects supported by community engagement can provide these additional opportunities to honor the history and create new recreational opportunities.
The NRWA is now partnering with the City of Fitchburg, and the engineering firm of Fuss & O’Neill, to remove McTaggart’s Dam on Phillips Brook, which is a tributary of the North Nashua River. Removal of that structure will reconnect 5.65 miles of habitat, allowing fish, water, and nutrients to move freely along this section of the brook once more. Read more about the McTaggart’s Dam project.
For human communities, taxpayer savings and improved public safety. For natural communities, reconnection, free flow, and healthier habitat. A win-win for all!
McTaggart’s Dam on Phillips Brook in Fitchburg, MA, view of the dam wall from downstream.