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CT Rivers Community
CT Rivers Community
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Search for your river, click on a drainage basin or visit the complete
for the location of each drainage basin.
Connecticut Drainage Basin
Housatonic Drainage Basin
Hudson Drainage Basin
Pawcatuck Drainage Basin
South Central Coast Drainage Basin
Southeast Coast Drainage Basin
Southwest Coast Drainage Basin
Thames Drainage Basin
South Central Coast
Table of Contents
1. About this Watershed
5. Human Use & Impact
6. Flora (Plants)
7. Fauna (Animals)
8. Lesson Plans & Field Studies
9. Personal Stories
10. Community Groups
12. Related Links
1. About this Watershed
The watershed forms in the north-west corner of Killingworth, on the eastern edge of the Hartford Basin, at an elevation of 300 feet msl, in an area of streams, swamps, bogs, and wetlands. It finally takes the form of a river and begins its flow toward Long Island Sound, through a dry lake bed that was once part of Lake Hammonasset. As it flows, it forms the border between the counties of New Haven and Middlesex.
At the southwestern end of the lake, a dam restrains the river and retains its waters in a 100+ acre reservoir. The spillway elevation is 273 feet. The water has descended only about 30 feet in the seven or eight rambling miles since its formation; it will fall the remaining 273 feet in the eight linear miles it flows to Clinton Harbor and Long Island Sound.
As the river moves through Madison and Clinton, population density increases, and industry begins to impact the waters. Threats from new large scale housing developments, industrial pollution, and destruction of salt marsh habitat are a constant challenge to the river, its watershed and its estuary.
The Hammonasset River Watershed stretches from Durham to Clinton and includes the towns of Killingworth and Madison. The Killingworth, Madison and Clinton Basins include about 56,000 acres. The charts on the pages 9 through 11, show the town boundaries, the watershed boundaries, watercourses and surface flow.
The Estuary as seen from the sound, Hammonasset Beach is on the far left, with salt marsh bracketing the river as it sweeps around Cedar Island. Shifting sand bars on the right guard the entrance to the harbor.
The Hammonasset River encompasses several different ecosystems. At its headwaters, fresh water swamps, bogs and streams form an inland wetland environment. From Lake Hammonasset to its junction with Route 95, the river flows through a typical New England hardwood forest. It empties into Long Island Sound through one of the most important tidal salt marsh basins in the northeast. In combination with the Indian River and the Hammock River, both of which join it in Clinton Harbor, it forms an incredibly rich estuary of sand flats, miniature barrier islands and tidal wetlands.
Downstream of the dam at Lake Hammonasset, the river runs through bucolic settings, land preserved by the Madison Land Conservation Trust on the west bank and the Killingworth Land Conservation Trust on the east. Hiking trails accompany the river for many miles, as its flows toward the Sound. Several environmental groups work to keep the area as natural as possible. In addition to the Land Trusts, a group called Friends of Hammonasset work to protect the area of the State Park and the surrounding Salt Marsh.
While most people are intent on enjoying the natural beauty of this river there are those whose sensibilities are not as well developed.
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Between 500 hundred and 300 Millions of years ago, as continents were lurching around the surface of the globe, trying to find permanent homes, several events occurred which resulted in the formation of the geological area we call Connecticut. We know from studying plate tectonics that land masses came together in slow motion, over millions of years, but with violent effect, causing one land mass to be forced under another in a process called subduction. The force of these impacts caused mountains to be thrust up, and oceans to be obliterated, as yet new oceans formed. One result of all this movement was the formation of the super continent known as Pangaea.
In Connecticut, there were at least three different collisions between other land masses and what we know as Proto-North America. First, a small group of islands called the Taconic Arc crashed in to an area that is now Western Connecticut. This was followed by a small continent called Avalonia, and finally, and most impressively, the land mass that was Proto-Africa slammed into North America, closing the Iapetos Ocean and creating a major subduction zone, right under our feet. All of this activity wrinkled up the edges of the continent and produced an extensive network of north-south ridges that became the foothills and mountains of the Appalachian Chain, which reached more than 20,000 feet into the air. Heat and pressure, during the subduction process, molded the rocks into the metamorphic gneisses and granites we know so well today, and tectonic processes thrust them high above the earth’s surface.
Four different terranes, or distinct geological strata make up the geology of Connecticut. They lie draped over the state in a south to north alignment. In the far west, the Proto-North American terrane was the original continental margin perhaps formed by an impact from the Taconic Island Arc. The Avalonia terrane along the extreme southeastern Connecticut border was formed when a small continent, Avalonia, slammed in to the western part of Connecticut. The Iapetos terrane, which makes up the majority of the area between the two boundaries, was formed from the rock and sediment thrust up from the subduction zone as the Iapetos Ocean disappeared. About 200 million years ago, a fourth terrane, called the Newark terrane was created when Pangaea began to break up. As the continents began to drift apart, a rift valley began to form along their lines of separation. The rift was unsuccessful, however, as forces further to the east split the landmasses apart and began to form a sea that would become the Atlantic Ocean . The central valley continued to receive new material from magma flows, and the rifting process caused tilting and uplifting of the land, which resulted in the long trap rock ridges that are the most prominent feature of the local landscape. These steep trap rock ridge formations created lakes, some of which are still with us today, Lake Gaillard, near New Haven, is an example.
The next significant event began with the cooling of the earth, about 35 million years ago. The age of glaciation had begun, and over the last 3 million years, Connecticut would get buried by ice at least three times. The most recent glacier arrived about 80,000 years ago and began to recede just 17,000 year ago. At the peak of the glaciation, the forward edge of the ice mass reached the area we now know as Long Island. Sea level was about 250 feet below today’s levels, as all that water was contained in the ice. As the glaciers began to recede, all of the rocks and rubble that had been pushed southward by the glaciers’ expansion remained behind. The land mass of Long Island was left to define the terminal moraine, the farthest area reached by the ice. The coast of Connecticut is, for the most part, a recessional moraine: a stopping point where the glacier slowed its retreat and deposited more rocks and soil. Between the two, great lake Connecticut formed. This large fresh water lake grew until its size, combined with the rise in sea level caused by melting glacial-water finally forced a breach to the ocean, in the area we now know as “The Race”, an area of strong current and flow between Fisher’s Island and Plum Island on the northeast end of Long Island. When the glaciers retreated, they left a landscape of rocky ridges, glacial ponds and deposits of large boulders, called glacial erratics, to dot the landscape. As the ponds became swamps and water started its inevitable journey down hill, many small streams and rivers began to flow toward the rising sea. The coastline of modern day Connecticut is riddled with the estuaries of these many waterways.
The most significant of these waterways is the Connecticut River, which forms more than 300 miles to the north in southern Quebec, flows through Vermont, New Hampshire and Massachusetts before reaching Long Island Sound between the modern towns of Lyme and Old Saybrook. To the east, the Thames River flows through Groton and New London, and to the west the Housatonic River reaches the Sound through the towns of Stratford and Milford. But there are many smaller waterways. Each has played its part in the history of the area, providing natural boundaries for settlements, access to the interior regions, and the flowing water necessary for the survival of a community and the development of industry.
Near the coast of Connecticut where the Avalonia Terrane abuts the lower edge of the Iapetos Terrane, about twelve miles west of the Connecticut River, lies a small watershed formed by the Hammonasset River. From the north and west, the watershed begins in an area of brooks, bogs and wetlands at an elevation of about 300 feet above the current sea level, eventually forming a river which begins to wend its way southward toward Long Island Sound. Man has managed the river, by engineering a dam to interrupt its natural flow to form a reservoir named Lake Hammonasset. With an area of a little more than 100 acres, the lake is restrained by a concrete barrier about 30 feet high and 100 feet wide. On a recent steamy afternoon, water flowed over the edge of the dam, creating a minor torrent at its base as it rushed down through a rocky pool, under the highway bridge at Route 80, and began wending its way through forest, meadows, and salt marsh to Clinton Harbor, where it meets the smaller Hammock and Indian Rivers to form a tidal estuary, which empties into Long Island Sound through a mini-delta of sand bars and artificial breakwaters.
It is hard to look at our modern rivers now, and try to understand what they might have been like thousands of years ago, before the impact of people, and buildings, and dams, and bridges, and highways. The Hammonasset, in its short flow to the sea has been altered several times by the hand of man, yet here and there in small places along its path, it is possible to imagine a pristine stream flowing through hardwood forest to a primeval sea.
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No published hydrologic data exists specifically for the Hammonasset watershed, however, by using precipitation data for Hamden, CT (pages 12 and 13), discharge data from the Indian River which flows into Clinton Harbor along side the Hammonasset, (pages 14 and 15) and groundwater data for two wells in Clinton adjacent to the Hammonasset area, (pages 16 and 17) we can make certain assumptions about water movement in the basins. Data is presented for the Water Year, 2005. It is evident that stream discharge closely mirrors precipitation, with the lowest discharge levels occurring July through September. Groundwater levels also reach their lowest points in the same months, indicating that precipitation and discharge are consistent with changes in the water table. More impermeable surfaces, which will accompany any large scale development in the area will result in quicker runoffs, possibly adversely affecting the water tables and stream discharge patterns.
Information about the watersheds and the towns is readily available from the Town Halls and online. Information on Lake Hammonasset and its dam, however, is a little harder to come by. A request to the Regional Water Authority solicited the response included on page 18. It is reassuring to know that terrorists as well as residents will be defeated in their attempts to gain access to sensitive information about this important hydrologic structure.
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Man first came to the Connecticut valleys about 12,000 years ago, after the last ice age. Originally living as nomadic hunters, they settled and became hunter gatherers. By the time European settlers first reached this area the ‘Indians’ were accomplished agriculturalists. The Hammonasset Indians were one of five woodland tribes that inhabited the lower Connecticut valley. They were mostly farmers, subsisting mainly on corn, beans, and squash, but they also fished and hunted. The Indian word "Hammonasset" means, "where we dig holes in the ground", and refers to the place where they farmed along the Hammonasset River.
“The sachem, or leader, of the Hammonassets was Sebaguenosh, which means 'man who weeps.' He had several reasons for being the man who weeps. His beloved and beautiful daughter married Uncas, sachem of the Mohegans, who was also a traitor to his red brothers. In the same marriage Sebeguenosh lost the control of his lands to Uncas, who turned around and sold them to the whites.” from ‘A History of Hammonasset’ researched and written by Gary Dunn of the CT DEP.
Europeans first settled in the Hammonasset area around then the middle of the 17th Century. Moving east from New Haven, and west from Rhode Island they settled the towns now known as Guilford, Madison, Killingworth and Clinton. Several changes occurred in nomenclature and geography before the current arrangement of towns and counties was adopted. The Hammonasset River became the boundary for the towns of Clinton and Madison and for a large section of the border between New Haven and Middlesex County. A history of Middlesex County, published in 1884, gives a glimpse of what it might have been like 200 years early in 1663.
On the west was no ford on the Hammonassett River, except about two miles north of Main Street, Clinton, just below Hammonassett Mills. Tradition says that footmen between Saybrook and Guilford kept along the seabeach of Long Island Sound. But there was a delightful spot at the head of a beautiful harbor, where the first settlers located Main Street. This street runs a little north of west and south of east about a half mile north of the head of the harbor. An abundance of oysters, fish, and clams were to be found in the harbor and in the rivers as far up as salt water flowed. -from ‘The History of Middlesex County 1635-1885’, J. H. Beers & Co., 36 Vesey Street, New York, 1884, Pages 417 – 434 by Frederick Kost (1861-1923).
By the beginning of the 18th century a viable community of farmers had settled in the area around Hammonasset. Salt hay from the marshes was a valuable product as it was used both for feed and for insulation for ice, which was harvested in the winter from the ponds and shallow bays in the area and stored in ice houses. Fishing was a major industry, for food, fertilizer and for oil.
During the 1790's the major activity was porpoise fishing. Between 1792 and 1793 some 600 or 700 porpoise were caught for use as fertilizer and fin oil. The Hammonasset beach was used as the site for the burning down process, a part of the process in the manufacture of fish oil. ~from ‘A History of Hammonasset’ researched and written by Gary Dunn of the CT DEP.
Of course, in the 21st Century, porpoises are not frequent visitors to the area. Over-hunting and pollution from pesticides and PCBs have driven them away and helped ensure that they no longer exist in significant numbers in Long Island Sound.
By the 17th Century, there were already mills on the Hammonasset River. An old drawing entitled the Mill at Nineveh Falls on the Hammonasset shows an early mill. Note that the area surrounding the mill is clear of trees, and the river looks far from natural as it flows by the old mill.
There were four mills located on the Hammonasset River: two sawmills, a gristmill, and a pulp and paper mill. The gristmill and one of the sawmills were located where the Railroad bridge, I-95 and River Road cross the Hammonasset River. The dam and some of the foundation is still present. The other saw mill and paper mill were farther upstream almost in Killingworth. The lumber from these mills went to support the ship building trade of Madison. Many of the planks were floated down the Hammonasset River, and then they were taken to East and West Wharves [in Madison]. Many of the schooners and other ships were tested in the waters off of Hammonasset Beach.
~from ‘A History of Hammonasset’ researched and written by Gary Dunn of the CT DEP.
In the 1920s the State of Connecticut began acquiring land for Hammonasset State Park, the area had been owned by the Winchester Repeating Arms, Co. and used as a gunnery range for testing weapons and ammunition. To control mosquitoes, drainage ditches were dug in the salt marsh at about 125 foot intervals. The State has continued to develop and expand Hammonasset and it has become one of the most popular locations in the State Park system. Rum-running was a popular past time during prohibition and Clinton Harbor and its rivers were active smuggling areas.
Railroad Bridge across the Hammonasset. circa 1902.
In the 1930s John Griswold established the airport along the Hammonasset that bears his name; it is the sight of a controversial new plan for high density housing development. In 1938 a Great Hurricane struck the New England coastline. Areas of the coastal floodplain were devastated.
At Hammonasset Beach, the boardwalk and many of the buildings were destroyed. The area was hit by another bad storm in 1955.
During World War II, Hammonasset Beach was closed and the area of beach and salt marsh was used as an aerial gunnery range. At least one aircraft lies in the murky waters of Long Island Sound right off the beach. In the last half century, as Connecticut’s shoreline towns have become bedroom communities for suburban commuters, population pressures have had a noticeable impact on the Hammonasset watershed. Agriculture is no longer the mainstay of the area. Industry, commerce and residential development all are encroaching on the river and its environment.
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5. Human Use & Impact
Downstream of Route 95, industry and population make their presence felt. Unilever operates the former Cheeseborough Ponds plant in Clinton (not in picture). For several years, pollution from wastewater and runoff has impacted the Hammonasset River through Hayden Creek. Unilever has been identified as a point source for lead and zinc pollution. Clinton Nurseries runs a big greenhouse and topsoil complex (upper left) with potential for pollution from pesticides and fertilizers. In the left foreground, the Stanley-Bostitch Wire facility in Clinton ranks high in production related wastes and non-cancerous health risks from land, air and water discharge. Located just southwest of the Route 1 bridge (middle right) Shore Chemical has been cited for chemical pollution including mercury contamination. In the background, the large marina facilities in Clinton Harbor are contributors for pollution from boats and support services such as painting, repair and manufacturing.
Clinton Harbor is an EPA designated NO DISCHARGE ZONE, meaning all vessels must make use of waste pump-out facilities, which does help alleviate concerns about human waste pollution. Pump it. Don't Dump it
High density housing adds to pollution. These roads and driveways increase runoff and the septic systems sit on a very shallow water table. This complex nestled in the tidal salt marsh south of Route 95, caters to senior citizens. For several years, members of the community have been fighting to keep a developer from turning the 42 acre Griswold Airport site into another huge development called “Madison Landing” where 122 row houses would cover just 20 acres of buildable land. The orange pond in the foreground, leaching into the marsh, is on the Stanley-Bostitch Wire property.
Griswold Airport Development: A Grave Environmental Threat
While Griswold Airport has been in continuous operation since the 1930s, its use over the last several years has been minimal due to the uncertainty of its future. The facility has not functioned as a full service fixed base operation since the late 1980s. No fuel or maintenance is available at the airport, but several aircraft, most notably ultra-light and experimental types are based there. During the 1980s attempts to lengthen the runway were rejected by the EPA and the Connecticut DEP due to the sensitivity of the ecology and the fragile habitats that abut the airport. The airport serves as a buffer between the commercial and residential congestion of the Post Road and the tidal salt marsh that forms the border between the runway and the Hammonasset River. Of its 42 acres, 10 are tidal wetlands.
Over 400 feet of the airport boundary lies along tidal salt marsh in the Natural Area Preserve. It has more than 450 feet of frontage on the Hammonasset River. Much of the airport lies in a coastal flood hazard area. In 1985, during Hurricane Gloria, the majority of the property was under nearly a foot of water.
“The U.S. Fish & Wildlife Service has said the following about this area. ‘The intertidal mud flats at the mouth of the Hammonasset River are one of the largest and most exemplary natural wetland areas of this type in the State, and are important feeding areas for many shorebirds. The nearshore waters and sediments of this complex contain large concentrations of American oyster and are important spawning and nursery areas for winter flounder; this area is also significant for its high diversity of marine fishes. The rivers have important anadromous fish runs of sea-run brown trout, alewife, blueback herring, American shad, white perch and sea lamprey.” [letter from Henry Ferris to CT DEP, August 20, 2002]
Despite these obvious environmental issues, the Madison Planning and Zoning Board has repeatedly approved projects that threaten the ecological viability of the site. Through an organization known as “Stop Griswold Over-Development” (SGOD) local environmental and community leaders have been relentless in bringing attention to the shortfalls of the development plan put forth by the most recent applicant, Leyland Alliance, LLC. So far, only the reluctance of the Department of Environmental Protection to approve a sanitation plan for this high density development, and the volubility of the community opposition have sustained the airport in its current condition. The issue will come to a head this summer as options to purchase are set to expire. A new sanitation proposal was recently submitted and everyone is awaiting the DEP decision.
Unilever Waste Water Treatment: A Great Environmental Succcess?
Senator Meyer and state Rep-representative Deborah Heinrich (D-Madison) on the banks of The Hammonasset River in Madison, celebrating the State Bond Commission's approval of $500,000 to help the Unilever Corporation create an on-site wastewater treatment plant. The
money will help prevent Unilever from dumping wastewater into the
Hammonasset River. (April 5, 2005) Press Release
Unilever will contribute $7 million toward the construction of the system.
Other Environmental Issues – The Impact from One Small Site.
The DEP has been monitoring the Shore Chemical Company since 1980. This single building with a loading dock and drum storage area has quite a history:
Raw materials used on site include phenylmercuric nitrate, zinc
oxide, 1,2,4-trimethylbenzene, 1,3,5-trimethylbenzene, chloroform, methyl ethyl ketone, and glycerine. Wastes generated from on-site processes include machine oil, kerosene, ethyl alcohol, chloroform, and rinse water containing methyl alcohol, hydrochloric acid, caustics, and isopropyl alcohol.
In 1991, a CT DEP investigation revealed two 55-gallon drums and 17 1-gallon jugs of liquid laboratory wastes located along the outside southern wall of the building. Of the 17 1-gallon jugs, six were either broken or had been spilled on the ground. Three 55-gallon drums and two 5-gallon drums of unidentified liquid and two 30-gallon fiber drums of unidentified solid material were discovered in the wooded area south of the building. Several hundred empty 55-gallon drums, 30-gallon drums, and 5-gallon drums were found in the wooded [File photo – not actual site] area in the southern portion of the property.
In 1996, approximately 150 cubic yards of mercury contaminated soil were excavated from the former laboratory waste discharge area and disposed of off site. U. S. Environmental Protection Agency (EPA) investigations at the property include a Preliminary Assessment (PA) in 1988 and a Site Inspection (SI) in 1993.
The estimated population served by public drinking water supply wells within 4-radial miles of the property is 9,430. The nearest public drinking water supply well is located within 0.5-radial miles of the property. The estimated population served by private drinking water supply wells within 4-radial miles of the property is 11,025. The location of the nearest private drinking water supply well is unknown. The depth to groundwater in overburden and the direction of groundwater flow
are unknown. No groundwater samples are known to have been collected from the property. No impacts to nearby groundwater drinking supply sources are known or suspected.
Stormwater runoff from the property is expected to flow southeast to Hammonasset River. Additional surface water bodies located along the 15-mile downstream surface water pathway include Clinton Harbor and Long Island Sound. There are no drinking water intakes located along the 15-mile downstream surface water pathway. The property lies within the 100-year flood plain of Hammonasset River. Sensitive environments that occur along the downstream pathway include 11 miles of wetland frontage, a Clean Water Act (CWA)-protected water body, fisheries, and an unknown number of Federal- and State-endangered or threatened species habitats. Analytical results of surface water samples collected from Hammonasset River in 1992 indicated
the presence of chloroform, 1,1,1-trichloroethane, isopropyl alcohol, and acetone. Based on analytical results, a CWA-protected water body appears to have been impacted.
From an EPA report on Shore Chemical Site, currently awaiting National Priority List Decision as a potential super fund site.
Something else to think about…
The Clinton Municipal Landfill is less than 1 mile from the Hammonasset River.
Since 1984, the property has been inactive as a landfill but has received stone-washing sludge from a local gravel quarry. From 1965 to 1984, the landfill reportedly received in excess of 200,000 cubic yards of municipal waste, industrial waste, and cover material. The industrial waste reportedly included volatile organic compounds (VOCs). In addition to the landfill, the town operated three sludge dewatering lagoons at the property. Materials deposited in these lagoons included metal hydroxides, non-petroleum based oils, industrial wastes generated in the manufacture of health and beauty products, waste-activated sludges, and oil-contaminated soil. In 1978, a reported release of 500 gallons of gasoline from an underground storage tank (UST) occurred; however, no record of a release was found in available files. The UST was removed in 1989 and soil samples from around the tank indicated the presence of VOCs. Connecticut Department of Environmental Protection (CT DEP) issued an Order to Abate Pollution in 1972 and 1985. Analytical results of sludge samples collected from the property between 1981 and 1992 indicated the presence of VOCs, inorganic elements, and polycyclic aromatic hydrocarbons (PAHs) on the property.
From an EPA report on theClinton Municpal Landfill, currently awaiting National Priority List Decision as a potential super fund site.
In Clinton, ground water testing as recently as 2004 reported high levels of nutrients and bacteria from pathogens potentially from septic systems and storm water runoff.
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6. Flora (Plants)
Vegetation varies greatly depending on the type of terrain. Damp environments foster ferns and mosses, shallow ponds are often covered with water lilies and duckweed, while bogs and marshes can be filled with cattails and lined with trees such as red maples, cedars and marsh alders. Shrubs such as laurel and blueberry can be found along with plants like skunk cabbage and the invasive purple loosestrife.
After decades of habitat loss due to filling and draining, the critical ecological importance of wetlands has finally been recognized. Inland Wetlands are actually defined and protected by the EPA and the Connecticut DEP, and strict regulations cover even minor impact on both public and private property.
While regulations are an excellent tool, in talking with Town Environmental Planners and Wetland Enforcement Personnel, it is clear that a concentrated effort to educate property owners as to the value of our wetlands is paramount to the success of a wetlands management program.
After leaving Lake Hammonasset, the river runs through a modern hardwood forest, containing oak, beech, and hickory trees. Maples and conifers also grow along the margins. Deer, raccoon, possums and fox can be found, along with the ubiquitous skunks, squirrels and chipmunks. There have been reports of coyotes as well. The forest is home to thrushes, nuthatches and vireos; warblers, woodpeckers and wrens. Wild turkeys have been reintroduced and are becoming increasingly common. Raptors such as red-tailed hawks and great horned owls feed on the mice and voles that inhabit the forest floor. These new growth forests have grown up over previously cleared land, where agriculture or deforestation left large areas of open space. The undergrowth is made up of mushrooms, ferns and shrubs. It is not uncommon for a stone wall to occur, seemingly at random, marking the boundary of some former farm.
On the higher ground along the boundaries of the river are occasional open spaces. These are often tended hay fields or fallow farm fields, but might just as likely be neglected open space, waiting for nature to take its course and repopulate it with nearby trees and shrubs. Grassland birds, insects and small mammals make their homes in these open areas and they are important to the survival of many species.
Significant Coastal Habitats
The greater Hammonasset Complex includes an area stretching from the Patchogue and Menunketuck Rivers in Westbrook to Tuxis Island in Madison, Connecticut. The Hammonasset River and its tidal wetlands combine with the Indian River and Hammock River wetlands to make up one of the largest tidal marsh environments in Southern New England. Offshore islands and barrier beaches add to the richness of this Significant Coastal Habitat.
The marshland is an estuarine tidal marsh graduating from fresh water marsh to salt marsh as it enters Long Island Sound. In its lower reaches, it is dominated by saltmeadow cordgrass (Spartina patens), with saltmarsh cordgrass (S. alterniflora) growing along the tidal creeks and old mosquito ditches.
Upstream, wild rice occurs in small stands. The adjacent upland is forested with hardwoods, predominantly red oak and pignut hickory. The marsh upland edge includes cattail, common reed (Phragmites) and various sedges. There are extensive beds of eelgrass and intertidal flats at the mouth of the Hammonasset River. Several relatively small and un-developed barrier sand beaches are found in this complex, often with dunes and beachgrass vegetation. Mean tidal range in this area is 4.5 feet (1.37 m).
The estuaries and marshes of this area are important for wintering waterfowl, especially American black duck, red-breasted and common mergansers, and bufflehead. Raptors, including ospreys, eagles, marsh hawks and owls frequent the marshes. Large numbers of waterfowl and shorebirds use this area during migration. Several of the surrounding islands have nesting colonies of piping plover and roseate terns listed as threatened or endangered species American oystercatcher, willet and great blue heron feed on the mudflats.
Roseate Tern, Scott Heckler, National Audubon
The nearshore waters are important spawning areas for winter flounder The rivers have important anadromous fish runs of sea-run brown trout, alewife, herring, American shad, white perch and sea lamprey.
Salt Marsh Reclamation
Since the early part of the century nearly 300 acres of Salt Marsh were drained along the Hammock River allowing Phragmites to gradually replace the vegetation, dominated by high marsh plant communities. During the summer, the tide gates were closed to drain surface water from the marsh, thereby eliminating breeding habitat for the salt marsh mosquito. However, without daily tidal flow sediments accumulated quickly in the ditches, which in turn trapped rainwater, creating an ideal habitat for mosquitoes.
The DEP and the Mosquito Control Unit began to restore the degraded wetlands in 1985 by utilizing modern open marsh water management techniques. A single tide gate was opened in the spring of 1985 and photo stations were established to measure the replacement of Phragmites by native marsh grasses. By the fifth and sixth year, Phragmites stopped growing, bringing improved vistas and the return of wildlife such as egrets and waterfowl.
Restoration of water quality is critical to the health of the living resources in this area including the natural oyster beds that line the channel of the Hammonasset River.
program developed by Charles Roman, a graduate student at Connecticut College
The Hammock River today
Despite the gains made in marsh reclamation and preservation of existing habitats, the 10,000 acres of coastal marshland in Connecticut is far from safe. In fact, scientists have been watching a new threat that could have a pervasive negative impact on our coastal wetlands. Called sudden marsh dieback, the phenomena has been observed throughout the New England States, particularly on Cape Cod. The same or similar disease has been observed from tidewater Virginia to the coast of Texas. In a series of recent articles in the New England Press, Ron Roza, a coastal ecologist with the Connecticut DEP, has been quoted: “No one recalls seeing anything like this... We're talking about a crime scene investigation - some forensic ecology, if you will." After rainforests, Rozsa continued, “This is the second most productive ecosystem on the planet. Fish forage and spawn on the marshes. They are also pollution filters and sediment traps. If you lose these areas, you release sediments into the rivers and streams.” The dieback seems to primarily target smooth cord grass, Spartina alterniflora, but other high marsh grasses may also be affected. “We don't know what's causing it, and we don't know how to stop it,” said Susan Adamowicz, a biologist with the U.S. Fish and Wildlife Service.
Wade Elmer, a plant pathologist with the Connecticut Agricultural Experiment Station in New Haven, has been to the dieback areas to collect soil and cord grass samples. Elmer researches fusarium, a soil-dwelling pathogenic fungus that can cause heavy damage to agricultural crops and is considered a possible culprit in wetlands dieback. So far, Elmer has determined that, if fusarium is the culprit, it is a non-native species. DNA testing has linked it to a strain from the Sudan. Whether it arrived on the winds or in the hold of a transoceanic vessel, if in fact, it is contributing to the dieback, it may be hard to come up with a remedial solution.
Sudden Death In The Marsh
Mysterious dieback threatens critical coastal ecosystem
By Judy Benson, Published on 6/25/2006. The Day of New London
Photo of Wade Elmer © The Day of New London.
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7. Fauna (Animals)
The Hammonasset River runs through a variety of significant habitats. At its inception, it is part of an area of inland wetlands, rivulets, bogs, swamps and vernal pools. Inland wetlands play a part in the hydrological stability of an area, controlling flooding and recharging and purifying the ground water supply. They provide important habitat for small mammals, birds, and insects. Vernal pools play a major role in the life cycle of many amphibians such as frogs, toads and salamanders.
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8. Lesson Plans & Field Studies
Add text and links here.
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9. Personal Stories
Submitted by John Kelly
Unspoiled, by comparison to many of Connecticut’s rivers, This river deserves to be protected from the pressures that can still destroy it. Its tidal marsh lands are among the largest in the state, and their survival is constantly at risk.
Despite our awareness of the critical need for our wetlands, the pressure to develop them is intense. All the concern over sea level rise and habitat preservation seems not to deter those whose desire for short term profit is stronger than their concern for the long term well-being of our environment. The need for careful management of our wetlands and their buffer zones is nowhere more obvious than at Griswold Airport, where 122 row houses could change the face of the Hammonasset estuary for ever.
Pressure also comes from chemicals in the groundwater and in the sediments of the estuaries. We need to support the EPA and the DEP, and encourage them to aggressively police those who by accident or design pollute our environment.
Pressure comes from the continuous arrival of invasive species: the wooly adelgid attacks our hemlocks; phragmites, purple loosestrife, and Japanese barberry crowd out our native plants; and zebra mussels and Asian shore crabs change our freshwater and salt water ecosystems in ways we are only beginning to understand. Can a fungus spore blown in from the Sudan on a cloud of dust suddenly poison our coastal salt marsh? If so, are we willing to commit the time, money and resources to find an antidote?
There are many groups devoted to the preservation of Connecticut’s coastal and riverine habitats. In the Hammonasset watershed, each town has its version of a Land Conservation Trust. National organizations such as the Audubon Society and the Nature Conservatory have chapters that are active on local and state levels. Specific groups such as the Stop Griswold Over Development focus on single issues. Long Island Sound and its coastal habitats are the focus of several interstate groups from New York and New England that try to promote a rational environmental policy for the eight million people that live in the cities and towns surrounding Long Island Sound. Among them, Long Island Sound Study, LISS, has made great stride toward promoting public awareness and focusing on restoration projects throughout the multi-state area. A two page outline of their restoration efforts is enclosed in the Appendix.
The message here should be self evident. We have a tremendous resource in the hills and valleys and rivers and wetlands of our local environment. It is our duty to understand them and enjoy them, and get involved in processes that will restore and maintain them for the good of us all. Our success at preserving areas such as the Hammonasset River and its estuary may serve as a bellwether for the future of our entire coastal ecosystem.
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10. Community Groups
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Hiking, Fishing, Kayaking, Canoeing, can all be enjoyed on the land and on the river. The Regional Water Authority maintains several miles of trails at Lake Hammonasset, including one with old Indian caves that are worth a visit. The Conservation Land Trusts of Killingworth and Madison both maintain marked trails along the river, and there are several places where a hand carried boat can be launched. Of course, facilities for larger boats are available in the marinas on the lower river and in Clinton Harbor. You can even learn to fly a powered parachute at Griswold Airport.
Hammonasset Beach is one of the most popular state parks in Connecticut, with swimming, beach combing, hiking and camping offered at nominal prices. The Nature Center has interesting exhibits, and the upland marsh and salt meadows are a bird watchers paradise. For those with an interest in local geology, remnants of the last glacier can be found along the paths and the coastline of Meigs Point.
On a recent muggy, overcast day we went for a hike on the Madison Land Conservation Trust trail on the west side of the river. Once you leave route 80 behind, you reach a part of the river you can pretend is pristine. We saw dozens of birds, common ones like sparrows and robins, and more unusual ones: osprey, goldfinches, red-wing blackbirds, and even a large great horned owl. Mountain laurel, rhododendron and water iris decorated the trail. Frogs, toads, and a snake were visible on the riverbanks. In the mud, were tracks of raccoon and deer. The occasional house reminds you that this is not the wilderness, but it is a pleasant walk all the same.
A foot bridge and the beams of a highway overpass frame a trout fisherman as he works his rod to deliver a fly to the riffle across the stream. Connecticut DEP stocks many of its lakes and rivers with thousands of
rainbow and brown trout each year.
The Hammonasset River is a Trout Management Area. Catch and release restrictions cover much of the river. Brook trout are the only trout native to much of the eastern United States. Brook trout survive in only the coldest and cleanest water. In fact, brook trout serve as indicators of the health of the watersheds they inhabit. Strong wild brook trout populations demonstrate that a stream or river ecosystem is healthy and that water quality is excellent. A decline in brook trout populations can serve as an early warning that an entire system is at risk.
See the brochures on trout and trout fishing in the Appendix.
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12. Related Links
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1. Bedrock Map of Connecticut
2. Bell, Michael. State Geological and Natural History Survey of Connecticut: The Face of Connecticut, People, Geology, and the Land.
3. CT DEP Geology of Hammonasset Beach State Park
5. Trap Rock Ridges, brochure prepared by the Natural Heritage Program Coordinator. Natural Resources Center, Department of Environmental Protection, Hartford, CT.
Section II: The Hammonasset Watershed
6. Water Resources Data Connecticut Water Year 2005, USGS
8. Water Quality in the Connecticut, Housatonic, and Thames River Basins USGS Circular 1155
9. Google Earth
Section III: History of Hammonasset
10. ‘A History of Hammonasset’ researched and written by Gary Dunn of the CT DEP.
11. The History of Middlesex County 1635-1885, J. H. Beers & Co., 36 Vesey Street, New York, 1884, Pages 417 – 434.
12. The The Charlotte L. Evarts Memorial Archives, Inc.
Section IV: The Hammonassett River Today
Section V: Human Impact on the River
13. Stop Griswold Over-Development (SGOD) v. Leyland Alliance, LLC (Madison Landing) Application for Subsurface Leaching System Application #200401781
14. Letter by Keith R. Ainsworth, Member, Evans, Feldman & Boyer, LLC. Counsel to Stop Griswold Over-Development.
15. Funkhouser, David. Developer Revises Plan For Project: Rethinks Water Treatment System, Hartford Courant. June 2, 2006
16. Letter from Henry Ferris, former president of Menunkatuck Audubon to the State of Connecticut proposing that the state purchase Griswold Airport Aug. 20, 2002
17. “Connecticut fishermen take any kind of threat to local waterways very seriously,” New Report by News Channel 8's Tricia Taskey (Clinton-WTNH, Mar. 17, 2005 5:25 PM)
18. Press Release
19. EPA NEW ENGLAND’S APPROVAL DOCUMENTATION FOR CT DEP’S HAYDEN CREEK TMDL ANALYSIS. Effective Date: April 19, 2002
20. CITIZENS for a CLEAN HAMMONASSET RIVER(CCHR) leaflets
21. ENVIRONMENTAL PROTECTION AGENCY[FRL-7967-4]Connecticut Marine Sanitation Device Standard
Section VI: Significant Habitats
23. National Audubon Society, Field Guide to New England. Peter Alden, Brian Cassie, Richard Forster, Richard Keen, Amy Leventer, Wendy B. Zomlefer. Alfred A. Knopf, New York, 1998
24. Northeast Coastal Areas Study SignificantCoastal Habitats Site 24 (CT)
25. Habitat associations in shallow water fish and crustaceans in estuaries of the northeastern U.S. by Beth A. Phelan, Dissertation Director: Professor Kenneth W. Able
26. HAMMOCK RIVER, CLINTON RESTORATION VIA TIDAL GATE MANAGEMENT. CT DEP Report
27. Depletion, Degradation, and Recovery Potential of Estuaries and Coastal Seas. Heike K. Lotze,1* Hunter S. Lenihan,2 Bruce J. Bourque,3 Roger H. Bradbury,4 Richard G. Cooke,5 Matthew C. Kay,2 Susan M. Kidwell,6 Michael X. Kirby,7 Charles H. Peterson,8 Jeremy B. C. Jackson5,9
28. Benson, Judy. "Sudden Death in the Marsh." The Day of New London 6/26/2006
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