River in North Reading, under flowing and dry conditions (D. Armstrong,
Ipswich River Watershed
Located in northeastern Massachusetts, the Ipswich River is an important
aesthetic, recreational, economic, and ecological resource. Its
watershed – home to about 160,000 people – includes
155 square miles of land and all or part of 21 communities. More
than 330,000 people and businesses depend on the river and its aquifers
for drinking water. Historically, the river has supported productive
fisheries and shellfish beds, and for over a hundred years, it powered
shipbuilders, tanneries, and textile mills. The Ipswich River estuary
is part of the 17,000-acre Great Marsh ecosystem extending up the
coast into New Hampshire.
About 74 percent of the watershed is forest
and various levels of residential land use, and about 10 percent
is covered by lakes, ponds, and marshes. Like many coastal river
systems, stream gradients in the watershed are low, and the river
and its tributaries frequently
flow through wetlands. These wetlands not only help maintain water
quality, but they contribute to the river’s base
flow, which keeps the river flowing during dry periods.
However, the most important contributor to base
flow throughout the watershed is groundwater. During much of late
summer and early fall, when evapotranspiration
rates and water withdrawals are high (and therefore groundwater
stores are low), streamflow in the Ipswich River watershed is severely
affected. In fact, segments of the river run dry on a regular basis,
resulting in fish kills, habitat changes, and other ecological damage.
Compounding the problem, nearly 80% of water withdrawals from the Ipswich
watershed are sent outside
of the watershed boundaries as either drinking water or wastewater,
rather than recharging the local aquifers.
As a result, American Rivers, a national river
organization, designated the Ipswich River the third most “endangered
river” in America in 2003, and the Massachusetts Water Resources
Commission now classifies the river basin as “highly stressed,”
the highest of three stress classifications related to flows.