About the Housatonic River Watershed

From: Connecticut Water Trails Association
The Housatonic River
The Housatonic River is approximately 149 mi (240 km) long, in western Massachusetts and western Connecticut in the United States. It flows south to southeast, and drains about 1,950 square miles (5,100 km2) of southwestern New England into Long Island Sound. Its watershed is just to the west of the watershed of the lower Connecticut River. The East Branch begins at Muddy Pond in Washington Massachusetts and flows a distance of approximately 17 miles, dropping 480 feet before merging with the main stem. The West Branch starts from Pontoosuc Lake and joins the Southwest Branch at Clapp Park in Pittsfield Massachusetts. From there it flows a short distance until it is joined by the East Branch at Pittsfield’s Fred Garner Park.

The Housatonic River main stem flows in a southerly direction 132 miles to its outfall in Long Island Sound at Stratford Connecticut. The main stem of the river has an overall drop of 959 feet. From its headwaters flowing south toward Great Barrington, the valley is narrow and the river flows quickly, characterized by several swift drops in elevation, before it emerges from the Berkshire Hills. In this section there is a good deal of commercial and industrial development. The lower region is rich in farmland, and through this section the river flows more slowly, meandering its way through the valley to Falls Village Connecticut.

From: Canoeing Guide for the Housatonic River in Berkshire County, Third Edition. Published by Berkshire County Regional Planning Commission and Housatonic Valley Association
Along most of its route through Berkshire County MA, the Housatonic River is flanked by a floodplain of soft alluvial (silty) soils. The floodplain varies in breadth from a scant hundred feet to over a half mile, through which the river is endlessly changing its course, leaving oxbows and sloughs to mark its former positions. The combination of early spring rains and snow-melt results in the formation of many temporary ponds spreading out across the plain.

The floodplain provides the basis for numerous plant communities. Red maple, oak,black willow, hemlock, white pine, cottonwood, and sycamore are examples of common tree species. In the shade of the trees, large colonies of ostrich and cinnamon ferns thrive along with spring wildflowers such as trillium, spring beauty, jack-in-thepulpit, and trout lily. Thickets of alder, dogwoods, viburnums and spicebush form a transition between tall trees and the fields. The open fields and pastures display a great variety of sedges, grasses and rushes including cutgrass, reed canary grass, joe-pyeweed, goldenrod and non-native species such as phragmites and purple loosestrife.

The variable nature of the floodplain habitat provides for an extensive and highly diversified mammal population: whitetail deer, red and grey fox, striped skunk, cottontail rabbit and red and grey squirrel, to name a few. There is also the opportunity to observe animals such as beaver, mink and otter, as well as the tunnels, cattail houses, and  tracks of the abundant muskrat.

The lush river margins support a large bird population with predators such as osprey, red-tailed hawk and red-shouldered hawk, sparrow hawk and the occasional bald eagle. If fortunate, one might see some of the nocturnal birds of prey – the owls: screech, sawwhet, barred and great horned. Kingfishers and bank swallows excavate nests in the sandy banks; warblers, red-winged blackbird and woodcock occupy the thickets; orioles, vireos and kingbirds nest in the tall trees. The shores and banks also provide nesting sites for a wide variety of song birds. The availability of pondweed, duckweed, and water plantain attracts many types of waterfowl to the river: mallard, wood duck, teal and black duck. During migration periods there are coot, merganser, bufflehead, and golden eye as well as large flocks of Canada geese. A variety of shore and wading birds can also be observed including the great blue heron, the green heron, American bittern, snipe and sandpiper.

Large goldfish, carp and bullhead meander among arrowhead, green algae and cattails which are common in calm backwaters. Where the water is faster and more oxygenated, game fish such as brook, brown and rainbow trout can be found. Black bass and pickerel dwell in a variety of habitats along the river. Reptiles such as snapping turtles, painted turtles and an occasional spotted, box or wood turtle may be seen sunning themselves on rocks or logs; possibly a garter or common water snake may be observed gliding through the water. Amphibians also share the watercourse; green frogs, leopard frogs, and bullfrogs are in abundance. Redbacked and two-lined salamanders live under stones along the banks.

From: Connecticut Water Trails Association
As the Housatonic River moves into Connecticut, the valley changes dramatically. The valley walls narrow and are flanked by hills on either side. The river now flows through a much harder substrate consisting of limestone, quartz and granite, and the river bottom becomes much rockier. There are still some agricultural activities in this northwestern part of Connecticut due to the presence of the river’s nutrient rich floodplains.

Just south of Bulls Bridge power station, water is diverted from the river and pumped uphill, through a penstock, to Candlewood Lake, the first pump storage reservoir built in the country. Constructed in 1926, it is the largest (5,400 acres) lake in Connecticut.

When river levels are too low to support the power generation at the Rocky River Power Station in New Milford Connecticut, lake water is sent rushing down the penstock and through the generators. Upon leaving New Milford, the river again changes dramatically, becoming a series of 3 in-stream lakes. Each lake is formed by a hydroelectric power dam. The Shepaug Dam forms Lake Lillinonah (1,900 acres) in Bridgewater. Farther south in Monroe, the Stevenson Dam, which is the largest, creates Lake Zoar (975 acres). The third lake is Lake Housatonic (328 acres), formed by the Derby Dam between Derby and Shelton.

The flow of the Housatonic River may vary in this area. River flows are periodically ”ponded” behind the dams when normal river flows are inadequate. The water is then released to turn the turbines which produce electric power. Below the Derby dam, the river begins its final change, becoming an estuary, where salt and fresh water mix. The Housatonic River estuary produces one-third of all the seed oysters which are a vital part of Connecticut’s commercial shellfish industry. In this lower 12 mile section of the river are tidal wetlands and salt marshes which provide important habitat for plants, birds, shellfish, finfish and other aquatic life. The Housatonic River enters Long Island Sound between Stratford and Milford Point Connecticut.

From: Connecticut Water Trails Association
Site History
The river’s name comes from the Mohican phrase “usi-a-di-en-uk”, translated as ”beyond the mountain place”.The Mohican family of the Algonkin Indians, who came from New York west over the Taconic mountains, were the first valley settlers. The river was sometimes known as “Potatuck”, or the “Great River”, until the 18th century. A large portion of the river basin was developed for agriculture in Colonial times.

The Housatonic River is located in a predominantly rural area of western Massachusetts, where farming was the main occupation from colonial settlement through the late 1800s. As with most rivers, the onset of the industrial revolution in the late 1800s brought manufacturing to the banks of the Housatonic River, in Pittsfield, MA. Water power played a prominent role in 19th century industrial development, and remnants of dams, mill races and iron ore furnaces can still be seen today. Northeast Utilities operates five hydroelectric facilities on the river today. Dams at three of these facilities – the Shepaug, Stevenson and Derby – form a chain of lakes, Candlewood Lake, Lake Lillinonah, Lake Zoar and Lake Housatonic, from New Milford south to Shelton.

Further down in the valley, in the areas of New Milford and Brookfield, tobacco farms flourished until the surge of 20th century development. South of Derby, industrial development, including steel mills and heavy manufacturing, characterizes the river. This stretch is also a tidal estuary, which supports a number of critical habitats for rare plants and animals and is a significant contributor to Connecticut’s shellfish population. The Housatonic estuary is the most consistent producer of seed oysters in the northeast as a public oyster bed, and generates over one-third of all oyster seed available to the state shellfish industry.

Inspired by the river during his honeymoon, the American classical music composer Charles Ives wrote The Housatonic at Stockbridge as part of his composition Three Places in New England during the 1910′s. The town of Stockbridge is located in extreme SW Massachusetts, the river entering from the east side of town then turning south towards Connecticut.

From about 1932 until 1977 the river received PCB pollution from the General Electric plant at Pittsfield, Massachusetts. Much of the upper section of the river in Massachusetts is still in agricultural use, however, past industrial discharges of PCB’s (polychlorinated biphenyls) into the river has created water quality problems. PCB’s still remain in the river’s sediments from Massachusetts to the Stevenson Dam in Connecticut. These synthetic organic chemicals can persist for decades and are a cause for concern and continued action. Although the water quality has improved in recent decades, the river continues to be contaminated by PCBs.

From: Connecticut Water Trails Association
Housatonic River Major Tributaries
Massachusetts:
Williams River
The Williams River begins at the outflow of Shaker Mill Pond in West Stockbridge MA and flows about 10 miles to join the Housatonic in the northern part of Great Barrington, MA.
Green River
The Green River, known for its frigid clear waters, emanates from No Bottom Pond in Austerlitz, NY and empties into the Housatonic in Great Barrington just north of the Sheffield border. About 10 miles of the Green River is in New York and a nearly equal length in Massachusetts.
Konkapot River
The Konkapot River begins at Lake Buel in New Marlborough and Monterey, and runs to its confluence with the Housatonic in Ashley Falls. For about 12 of its 14 miles, the river flows through Massachusetts with the remainder in Connecticut.

Connecticut:
Still River
The Still River begins in Danbury, Connecticut and flows north, entering the Housatonic in New Milford. Its watershed has an area of almost 72 square miles.
Shepaug River
The Shepaug River has its source west of Goshen, Connecticut and flows south, joining the Housatonic at the Bridgewater and Southbury border. The watershed of the Shepaug River is 156 square miles.
Pomperaug River
The Pomperaug River originates in Woodbury, Connecticut and merges with the Housatonic at Southbury. Its watershed is almost 89 square miles.
Naugatuck River
The Naugatuck River is the largest tributary, with a watershed of 312 square miles. It begins in Torrington, Connecticut and joins the Housatonic River in Derby.

New York:
Tenmile River
The Tenmile River, whose headwaters are in Connecticut, flows south through New York state and enters the Housatonic River at Gaylordsville, Connecticut. Its watershed covers 210 square miles, most of which lies in New York.

From: Connecticut Water Trails Association
Housatonic River Recreation
With more than 100,000 acres of public recreation land throughout the watershed, opportunities for swimming, canoeing/kayaking, fishing, sculling, boating, hiking, camping and cross-country skiing abound. The Appalachian Trail runs along the river for five miles between Kent and Cornwall Bridge, the longest stretch of river walk between Georgia and Maine. Farther north the trail again parallels the river for about one-mile in Sheffield, MA.

Since it is a mild river, boating is typically limited to canoes, kayaks. and floating-type trips. Many launch ramps are located along the river.

Housatonic River Whitewater
There are two sections of Connecticut’s Housatonic River: Falls Village to Housatonic Meadows State Forest and Bulls Bridge to Route 7.

Falls Village to Housatonic Meadows State Forest. Tucked away in the northwest corner of Connecticut, the Housatonic is set in the quaint hill towns that are built on the eastern slopes of the Taconics. The Appalachian Trail crosses the river at the put-in to this upper section, and two outfitters rent canoes for this run. The river comes out of Massachusetts, where its source is in the central Berkshires around Great Barrington. Its watershed is fairly large. Two hydroelectric dams store a small amount of water that is released when the demand for power is greatest (usually midday), making the Housatonic runnable most of the year.

Bulls Bridge is a local test piece for advanced paddlers. The drops below the covered bridge the Flume, S-Turn, and Pencil Sharpener are Class IV, while those upstream of the bridge Stairway to Hell and Threshold are solid class V. For the ultra-insane, Dead Horse Falls, on a side channel, is a dangerous class VI with only a few runs logged to date (one paddler broke several bones). The ledgy riverbed causes powerful holes to form at most water levels, and several of the drops are large, with Threshold leading the group at 30 feet plus, followed by Stairway to Hell at about 20 feet overall; the Flume falls 7 feet in a single plunge. The scenery is nothing to sneeze at either. Small cliffs appear from time to time next to the river, and the run takes you through the closest thing Connecticut has to wilderness, with pine forests, low rolling hills, and, of course, a covered bridge at the put-in.

From: Housatonic Valley Association
Edited by Jane Bakker
Researched by Elaine Kowalcky
Housatonic River Estuary, its wildlife, history, activities, water quality

What is an estuary?
Long Island Sound and the southern stretch of the Housatonic River, from the Far Mill River at the southern border of Shelton Connecticut to the mouth of the river at Stratford and Milford are estuaries – bodies of water where fresh and salt water mix. The tides drive the seawater from the Atlantic Ocean into Long Island Sound through the Race, the opening at the eastern end, and push the seawater westward and up into the Housatonic, Connecticut, and Thames rivers, where it mixes with the fresh water flowing downriver into the Sound. Estuaries are crucial breeding grounds for many marine animals, support a great variety of plant and animal life, and produce four times more organic matter than a fertilized cornfield.

The Housatonic River begins its 149-mile journey to Long Island Sound in Massachusetts. It flows south through western Massachusetts and Connecticut becoming tidal just below the Derby/Shelton Dam, and becomes an estuary at approximately the Far Mill River in southern Connecticut.

The Housatonic River estuary is made up of different landforms, or habitats, each having its own community of plants and animals which have adapted to local conditions and are dependent upon one another.

All living things within a habitat are tied together by a food web. Plants and algae are producers, using sunlight and nutrients to make food energy. The plants and algae are then consumed by microscopic animals, shellfish, larger fish, insects, turtles, rodents, and deer.

Larger hunters, including hawks, bats, skunks, and raccoons consume insects or small land animals. Large fish and water birds such as the herons, terns, egrets, and osprey consume smaller fish. Nutrients are returned to the natural community through the bacteria and fungi which decompose dead plants and animals. Every species in the food web eats, or is eaten by, another species.

Although estuaries, by their very nature, are resilient to change and environmental upset, human activities, if severe enough, can disrupt the food web. The disruption of even one species in this web causes a change in the entire network. Overfishing, pollution, and habitat destruction have caused species to disappear from the Housatonic estuary.

Estuary Habitats
The Housatonic estuary includes four types of habitat: uplands (well-drained soils with elevations up to 500 feet), tidal wetlands and mud flats, sand spits and barrier beaches, and the Long Island Sound.

The tidal wetlands and mud flats, low-lying areas that flood at high tide and are exposed at low tide, are one of the most important habitats in the estuary. Marsh plants slow and soak up flood waters, filter out chemicals and partially break down and take in pollutants, and also prevent land erosion by absorbing the force of wind and waves. Microscopic organisms and bacteria in tidal marshes break down dead plant and animal matter, cleaning the water and recycling nutrients into the estuary.

Since the late 1800s, 29 percent of Connecticut’s tidal wetlands have been lost due to construction, dredging, draining, dumping, and pollution. The Tidal Wetlands Act of 1969 has helped to save the remaining marshlands, with an average annual loss of wetlands since then estimated at one-quarter acre per year.

Milford Point at the river’s mouth, and Long Beach, west of Stratford Point, are sand spits and barrier beaches, which are important breeding areas for coastal birds and provide habitat for migrant and wintering species. A Connecticut Department of Environmental Protection program protects critical nesting sites of threatened species on Milford Point and the Great Meadows Salt Marsh in Stratford. Fencing the nesting areas and public education have helped increase nesting pairs in the estuary.

Threatened estuary wildlife species include the piping plover, least tern and the horned lark. Threatened plants are panic grass, beach needlegrass and false beach heather. The grasshopper sparrow is an endangered bird and endangered plants include the coast violet, lizard’s tail and saltpond grass.

In Long Island Sound and at the mouth of the Housatonic River, plants and animals living in the open water are either bottom-dwelling, called benthos, or dwell in the water column, which supports a wide variety of life including anadromous fish, such as Atlantic salmon. Anadromous fish must migrate into fresh water to lay eggs, or spawn. After the young hatch, they swim to salt water to mature. Anadromous populations have declined because dams on the Housatonic River prevent the fish from reaching their spawning grounds.

History of the Estuary
The original settlers in the Housatonic River valley were the Paugussett Indians, part of the Algonquian nation, who migrated from New York. They named the upper part of the river Pootatuck, or River of the Great Falls. Eventually, the Indian name Ousatonic, meaning place beyond the mountains, was given to the Housatonic River. The tribes settled along the riverbanks, farmed the fertile floodplains and harvested finfish and shellfish. Inland groups of Indians also traveled to Long Island Sound for salt and fish. The first record of the Housatonic made by a European was in 1614 by Dutch explorer Adrian Block, who sailed eastward from the Dutch settlement of Niew Amsterdam (New York). He named the river the River of Roodenberg, or River of the Red Hills.

The west shore of the lower Housatonic River valley was later settled by English colonists in 1639, when Reverend Adam Blakeman and many families from his church left Wethersfield, Connecticut and followed Indian trails to the river shoreline. They chose a protected harbor the Indians called Cupheag (The Harbor), where they began the town of Stratford. An historic marker, located on Shore Road behind the American Shakespeare Theatre, marks the location of Cupheag, now called Mac’s Harbor.

In the same year a group of English colonists from the Quinnipiac (New Haven) colony bought land surrounding the Wepawaug River from the Paugussett Indians and founded the Wepawaug Colony, which became Milford. Wepawaug colonists used Milford Point and the marshy eastern shore of the Housatonic for fishing, digging oysters, and hunting. From these two settlements the English colonists moved up the river valley, driving out most of the Indians, until they settled the entire valley.

The settlers depended on the river to survive and to move goods and people (the steep hills rising from the river shore made road building difficult). Each year spring floods deposited a new layer of fertile soil onto the flood plains. The colonists grew Indian corn, oats, barley, peas, beans, turnip, squash, and pumpkins and harvested spartina, one of the salt marsh grasses, to feed their farm animals. The river also provided an abundant supply of fish, clams, and oysters, and many migratory birds.

As the settlements grew, colonists harvested lumber, crops, and fish to trade with England and the English Caribbean colonies. The towns of Stratford, Huntington (Shelton), and Derby became commercial hubs where timber, fish, livestock, and crops were marketed to Boston, New York, Europe, and the West Indies.

Shipbuilding
The shipbuilding industry flourished in the Housatonic River estuary from the mid-1600s through the 1800s. One of the earliest shipyards was built in 1657 by Thomas Wheeler at Derby Landing just below the confluence of the Housatonic and Naugatuck Rivers. Hallock’s shipyard, the largest in the valley, launched 52 ships between 1824-1868. In 1685, across the river in Ripton (Shelton), Dr. Thomas Leavenworth built a warehouse, tannery and shipyard that operated from 1760 to 1812, and launched ocean-going schooners, sloops, and brigs. This land is now the site of Indian Well State Park.

James Bennett’s shipyard in Stratford, built in 1696, is now the Sikorsky Aircraft complex. In the early 1700s, Daniel Curtis opened a shipyard at the mouth of Ferry Creek and large schooners were built there during the mid-1800s. The 280-ton Helen Mar was launched in 1855, and the last boat was built there in 1938. This site is now the Stratford Marina. The last large shipyard was Housatonic Shipbuilding, where in 1918 the 2,551-ton, 267-foot steamship Fairfield was launched.

The Housatonic estuary communities remained major seaports until improved roads and railroads provided land access to markets and transportation centers. Completion of the Ousatonic Dam in Shelton and Derby in 1870 changed the river flow causing silt to build up below the dam making the river too shallow for large, ocean-going ships.

Bridges
Washington Bridge, the fifth bridge on its site since 1802, was built in 1921 and carries US 1 across the river. The I-95 bridge is named for the first ferryman, Moses Wheeler. The railroad bridge is on the national register, the fourth bridge at its location; the first, built in 1848, was, at 1,293 feet, the longest covered bridge ever built in Connecticut.

Manufacturing
Housatonic colonists built lumber mills for house construction and grist mills for flour. Paper, woolen, and bark mills followed. Mac’s Harbor is believed to be the site of the first mill in the river valley, most likely a grain mill powered by the Housatonic River tides.

James Blakeman built the first mill on the Far Mill River, betweenStratford and Shelton, in 1676. By the Revolutionary War, the Far Mill River supported 11 mills from source to mouth. Blakeman also built a dam on the Near Mill River in Stratford in 1685, which powered mills until the 1770s. The dam and pond, known as Peck’s Mill Pond, now forms a town park.

Small mills and foundries serving local needs were built in the Housatonic valley until the mid-1800s. In 1833, Sheldon Smith, his brother, Fitch, John Lewis and Anson G. Phelps, built the Birmingham Canal System on the Naugatuck River just above its confluence with the Housatonic. The village of Birmingham, which grew around the dam and canal to form the downtown business district of Derby.

The first factory along the canal, The Birmingham Iron Foundry, was completed in 1836, the same year that Edward N. Shelton and his brother-in-law, Nathan C. Sanford, built the Shelton Tack Company. By 1847, the village of Birmingham had 13 factories, using 18 water wheels.

Edward Shelton formed the Ousatonic Water Company in 1866 and completed the Ousatonic Dam spanning the river between Derby and Shelton in 1870, creating the first hydropower impoundment on the Housatonic River. The dam and canal attracted manufacturers to the west shore of the river in the Town of Huntington. By 1880, twelve factories, employing 1,000 people, were on the canal; eight still stand. In 1882, Huntington Landing became the borough of Shelton, named for Edward N. Shelton. By the early 1900s a mile of factories lined the Shelton river shoreline, and today, in Shelton and Derby, industrial development continues with new, state-of-the-art manufacturing facilities.

Fishing
Since the earliest days of English settlement, the Housatonic River has supported commercial fishing. The most important commercial fish taken from the Housatonic River was the American shad.

The adult males weigh up to six pounds and females as much as 12 pounds. Shad feed at sea as adults, returning to fresh water to spawn. By the mid-1800s shad fishing was an important seasonal occupation, which ended with the construction of the Housatonic Dam in 1870. For 20 years after that, shad could not pass the dam into the upper Housatonic to spawn and were easily caught.

By the end of the 1800s the species had disappeared from the Housatonic. Harvesting of American oysters from the floor of the Sound and the Housatonic estuary between Milford and Stratford began in the mid-1700s. During the 19th century the oystermen in Stratford and Milford discovered that the free swimming oyster larvae, called spat, attach to empty oyster shells about two weeks after birth, where they grow for the rest of their lives. Spreading oyster shells onto the oysterbeds in July would encourage spat growth. The oystermen’s demand for shells encouraged a unique operation known as shelling in Stratford. The shellermen would tong shells or run a powerboat over the beds to loosen the shells so they could be scooped or tonged. Nell’s Island was a favorite spot to store shells for sale.

Until the mid-1970s, pollution, over-fishing, predators, and hurricane damage caused the decline of oyster harvesting. The Connecticut oyster industry has been rebuilt through pollution control, erosion reduction to keep mud from covering spat, and good aquaculture practices. Now two-year-old seed oysters grown in the Housatonic estuary are transplanted offshore in Long Island Sound to grow in cleaner water for two or three years before they are harvested. The oyster beds are protected by the Connecticut Department of Agriculture and the Stratford Shellfish Commission. Connecticut has the largest aquaculture industry in New England. The Housatonic oyster beds are Connecticut’s major producers of seed oysters, and one of the largest north of Chesapeake Bay.

Many oyster beds in Long Island Sound are also cultivated for hard-shell clams, which is second only to the oyster as a commercially harvested shellfish. The beds are dredged to harvest clams after the seed oysters are removed. The hard-shell clam, also known as the quahog, littleneck, or cherrystone clam, was gathered by the coastal Indians for food. The shells were used as containers and tools, and were made into wampum beads for money and ceremonial use.

Watersheds and water quality
All rivers flow toward the sea, propelled by the force of gravity. The 1,948-square-mile Housatonic River watershed collects rain, snow and sheds it into the groundwater, streams and rivers which flow into the Housatonic River.

A drop of water falling anywhere in this watershed eventually arrives at Long Island Sound along with contaminants (nonpoint source pollution) such as oil, gasoline, fertilizers, pesticides, and road salt picked up along its journey from buildings, roads, parking lots, lawns and gardens.

Joined by point source discharges from pipes at industrial facilities and wastewater treatment plants, pollution draining from anywhere in the watershed may affect water quality in the estuary and Sound, and, if severe enough, harm plant and animal life and disrupt the food web.

Water quality in the estuary
There was a time when estuary shellfish were tinted blue-green, the result of high copper levels in discharges from metal finishing plants on the Naugatuck River which flows into the Housatonic at Derby Connecticut.

Copper, chromium and lead were introduced into the Naugatuck and Housatonic rivers through industrial and wastewater treatment plant discharges and combined sewer overflows. The regulation of point source discharges, upgrading of municipal wastewater treatment plants and elimination of most combined sewer overflows significantly decreased the concentrations of most heavy metals in the Housatonic River and estuary.

Several million pounds of lead pellets lie in the sediments at the mouth of the Housatonic at Stratford’s Lordship Point, the legacy of past trap and skeet shooting. This lead threatens waterfowl and aquatic life. It is estimated that half of the wintering black ducks that feed in the shallow waters on mussels, snails, sea worms and seeds have been poisoned by the lead.

Fortunately, cleanup plans include site dredging, recovering lead from the dredged sediment and returning clean sediment to the site. Saltwater, tidal and water circulation patterns have been affected by historic unregulated sand and gravel mining activities in the estuary which left behind deep dredge holes. Fine grain materials and organics settled in these pits, using up oxygen, leaving behind aquatic deserts where life cannot exist. Today, dredging is regulated and generally confined to navigational channels. Floatable debris (flotsam), such as plastic utensils and wrappers, paper cups, bottles, cigarettes, cans and other litter enter streams and rivers where they often injure or kill turtles, fish, birds and other life by direct ingestion or entanglement.

Today’s major water quality problem in the estuary is nutrient loading. Nutrients such as nitrogen, phosphorus and carbon enter the Housatonic River and its tributaries from wastewater treatment plant discharges. However, this source continues to decline — the result of ongoing state efforts to upgrade plants to require advanced treatment. A continuing source of nutrient loading is nonpoint source pollution. Atmospheric deposition of airborne pollutants and runoff from urban and suburban areas, septic systems, lawns, gardens, roadways, construction sites and upstream agricultural activities carry nutrients into storm drains, brooks, streams and eventually into the Housatonic River. Because these are widespread, they are difficult to identify and costly to regulate, and remain a contributor of nitrogen to Long Island Sound, which affects the Sound’s major water quality problem, hypoxia.

Hypoxia
In recent years a condition known as hypoxia, low dissolved oxygen levels in the water, has been developing in Long Island Sound. In summer, the sun heats the water near the surface and the dense, cooler water lies in a layer along the bottom. These two layers do not mix. Decomposing organisms in the bottom layer use up dissolved oxygen, and when the water of the estuary is calm there are no waves to mix in more oxygen.

At least three parts per million of dissolved oxygen in the water is needed to protect most estuarine species. If the oxygen level falls below this level, hypoxia occurs, and some bottom-dwellers may be affected. The condition gets worse excess nutrients flow into the Sound. The nutrients cause algae to “bloom” or grow explosively. When these algae die, they sink to the bottom increasing decomposition, sometimes using up almost all the dissolved oxygen thereby threatening all marine life.

From: Housatonic Valley Association
River Facts
-The Housatonic River is 149 miles long from its source at Muddy Pond in Washington, Massachusetts to Milford and Stratford, Connecticut.
-The watershed is 1,948 square miles (Massachusetts 499 sq. mi., New York 215 sq. mi., and Connecticut 1,234 sq. mi.)
-The river is tidal for 13 miles, from Derby to Long Island Sound, and is classified as an estuary for approximately 8 miles.
-Total fall from the source to the Sound is 1,430 feet (959 feet from the confluence of the East and West Branches in Pittsfield MA)
-The Housatonic River adds 11 percent of the fresh water that drains into the Sound.

Principal tributaries:
-Massachusetts: Williams and Green rivers.
-Connecticut: Naugatuck, Still, Shepaug, and Pomperaug rivers.
-New York: Ten Mile River.
-Six hydroelectric facilities generate more than 125,000 kilowatts.
-40 percent of Connecticut’s seed oysters are cultivated in the Housatonic estuary.

Long Island Sound Facts
-1,300 square miles, 110 miles long, and 21 miles wide at its widest point.
-577 miles of coastline, 95 miles of public beaches.
-15 million people live within the Sound’s drainage basin, and 44 sewage treatment plants discharge 1.2 billion gallons each day into the Sound.
-Connecticut has 36 cities and towns bordering the Sound, New York has 62, plus the New York City boroughs of Queens and the Bronx.
-16 major seaports which handle cargoes of mainly petroleum products, sand and gravel, and crushed stone.