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NEW ENGLAND COASTAL BASINS NAWQA STUDY UNIT DESCRIPTION
The New England Coastal Basins study unit encompasses 23,000 square miles (mi2) in western and central Maine, eastern New Hampshire, eastern Massachusetts, most of Rhode Island, and a small part of eastern Connecticut. Important drainage basins include the Kennebec (5,890 mi2), Androscoggin (3,520 mi2), Saco (1,700 mi2), and Merrimack (5,010 mi2) River Basins in Maine, New Hampshire, and northern Massachusetts, and the Charles (321 mi2), Taunton (530 mi2), and Blackstone (335 mi2) River Basins in Massachusetts and Rhode Island. Mean annual streamflow in these rivers ranges from 302 cubic feet per second (ft3/s) in the Charles River at Waltham, Massachusetts to 9,080 ft3/s in the Kennebec River at North Sidney, Maine. Most of these rivers originate in mountainous forested areas and their headwaters are often fast-flowing, cobble and boulder bottom streams. The study unit also contains a large number of natural lakes, many of which are enlarged and controlled by dams. The largest are Moosehead Lake in Maine (117 mi2) and Lake Winnipesaukee in New Hampshire (69 mi2). Cape Cod has no major streams, yet has more than 350 lakes and ponds.
Two principal types of aquifers underlie the study unit: stratified-drift aquifers and fractured-bedrock aquifers. Stratified-drift aquifers are the most productive and are used intensively for public drinking-water supply; several are sole-source aquifers. These aquifers were formed during the retreat of the last glaciers more than 12,000 years ago, as meltwater streams deposited stratified drift composed of sand, gravel, silt, and clay in valleys and broad plains. Bedrock in the study unit ranges in age from Precambrian to Mesozoic and includes primarily fractured crystalline igneous and metamorphic rocks; small areas of Pennsylvanian age sedimentary rocks are found around Narragansett Bay and in southeastern Massachusetts. Wells drilled in the fractured crystalline and sedimentary rocks in the study unit generally yield less ground water than wells completed in the stratified drift, but the bedrock aquifer remains an important source of water for some municipalities, industries, and many individual homes not connected to a municipal water-supply system.
An estimated 7.8 million people lived in the study unit in 1990. At that time, land use was an estimated 75 percent forested; 11 percent residential, commercial, and industrial; 6 percent agricultural; 5 percent water bodies, and 3 percent other uses. The New England Coastal Basins study unit contains a mixture of rugged mountains, narrow to broad valleys, and flat plains. Elevations in the study unit range from sea level along the coast to greater than 6,000 ft in the White Mountains of New Hampshire.
A summary of the study area can be found in the fact sheet: