A Long Dam Building History

Today there are 3,000 dams in Massachusetts, of which 606 are located in Southeastern Massachusetts. Most of these privately owned dams are relics of our mill industries, no longer have any human benefit and are in serious disrepair. (Click here for the link to the May 2006 State Committee on Post Audit and Oversight regarding Dam Safety: www.mass.gov/legis/bills/senate/st02/st02549.htm).

Dams fragment river habitat, alter stream flow, concentrate pollutants, and prevent river herring from spawning in their historical breeding grounds. Even small dams can block passage. Due to loss of spawning habitat only 9 of the 200 colonial herring runs were still active in Massachusetts Bay in 1920 and sixty percent of Rhode Island historic runs no longer exist. Watershed Associations of SEMA work closely with the State Division of Marine Fisheries in efforts to build fishways to help river herring access their spawning grounds. One-hundred runs have been re-established state-wide since 1920, but nearly 50% of fishways are in fair or poor condition.

Today, most of the dams in southeastern Massachusetts are in serious state of disrepair and many are safety hazards. Over 40 dams “over-topped” or were recently damaged during high rain events. Dams need to be assessed and priorizited for removal. Where dams are necessary, fish passage should be in place.

Spawning ground is lost when the river’s natural flow is altered. Often this is due to agriculture or water supply needs. However, we can satisfy both by better managing flow levels. This is particularly critical in the autumn when the fish return to the sea in the fall and during times of little rainfall.

More and more communities are removing dams in order to restore fish and improve water quality. Two dams have been removed in SEMA to date, one on Town Brook in Plymouth (2002) and one on Red Brook in Wareham (2006). For more information, go to the Massachusetts’ Riverways Program website at www.mass.gov/dfwele/river.

Dams: What We Can Do Now

Develop target fish communities for impaired rivers, specifying fish species that would exist in a healthy river ecosystem (defined by water quality, flow and habitat), and establish restoration goals to achieve target fish communities in our rivers. Promote passage of the dam safety bill that includes environmental assessment and financial incentives for dam removal.
Improve fish passage at dams and other obstructions to fish movement, and streamline the permitting process for these projects.
Assess the condition of instream dams, determine and prioritize removal of unnecessary dams, and streamline the permitting process for dam removal.

Find a Herring Run Near You

Launch the Free Passage kiosk

Restoring Water Quality

The biggest cause of surface water pollution in the state is pathogens and stormwater is an important source in Southeastern Massachusetts. Stormwater run-off washes bacteria from a wide range of sources into surface waters through stormwater systems or as overland flow directly into surface waters. Pet and wildlife waste, illicit discharges to stormwater systems, and failing private septic systems all contribute to high bacteria concentrations in stormwater.

Residents can make a huge difference in reducing the pollutants reaching our rivers via stormwater run-off. Changes in both the type and amount of fertilizer used, regular septic maintenance, and the disposal of your dog’s waste can and do make a difference. For information about fertilizer go to www.greenscapes.org.

Sixteen of the 17 estuaries from Cohasset to Plymouth have been significantly impacted by bacteria in stormwater. Significant portions of the Taunton River and the North River are polluted by pathogens related to wastewater treatment plants operating over-capacity and discharging unprocessed sewage into the rivers (Taunton and Rockland).

The Clean Water Act Phase II requires towns to control pre- and post-construction stormwater run-off for developments that are one or more acres. Municipal oversight for both pre and post construction drainage systems with on site enforcement is needed. As part of this design review, consideration should be given to that fact that probably the most effective means of reducing stormwater contributions to pathogen impairment is to reduce the volume of runoff by increasing infiltration to groundwater. Low impact development approaches to stormwater on the lot level result in a reduction in flushing of bacteria from contaminated surfaces and bacteria are removed from water that infiltrates though the soil matrix.

Water Quality: What We Can Do Now

Assess 100% of our rivers to determine the attainment of designated uses for each waterbody, through a partnership of DEP monitoring efforts and watershed association volunteer monitoring programs.
Reduce significantly or eliminate sanitary sewer and combined sewer overflows.
Require and support effective municipal, industrial, commercial and state agency stormwater management programs. Promote passage of storm water bylaws and local storm water utlities.
Develop personal life styles that support our rivers by being mindful about fertizers, septic care, pet waste, and personal care products that may harm our rivers.

For more information about stormwater:

www.nsrwa.org/programs/stormwater_management.asp
www.nsrwa.org/programs/low_impact_development.asp