Great Bay (New Hampshire)
Encyclopedia
Great Bay is a tidal estuary located in Strafford
and Rockingham
counties in eastern New Hampshire
, United States
. The bay occupies over 6000 acres (24.3 km²), not including its several tidal river tributaries. Its outlet is at Hilton Point in Dover, New Hampshire
, where waters from the bay flow into the Piscataqua River
, thence proceeding southeast to the Atlantic Ocean
near Portsmouth
. The northern end of the bay, near its outlet, is referred to as Little Bay.
watershed, the Great Bay Estuary is a drowned river valley composed of high-energy tidal waters, deep channels and fringing mudflats. The entire estuary extends inland from the mouth of the Piscataqua River
between Kittery, Maine
, and New Castle, New Hampshire
through Little Bay into Great Bay proper at Furber Strait, a distance of 12 miles (19.3 km). The Great Bay Estuary is a tidally-dominated system and is the drainage confluence of three major rivers, the Lamprey
, Squamscott
, and Winnicut
. Four additional rivers flow into the system between Furber Strait and the open coast: the Cocheco, Salmon Falls
, Bellamy
, and Oyster
rivers.
The Piscataqua River is an ocean-dominated system extending from the Gulf of Maine at Portsmouth Harbor and forming the border of New Hampshire and Maine to the fork of its tributaries, the Salmon Falls and Cocheco rivers. These rivers, several small creeks and their tributaries and ocean water from the Gulf of Maine create the Great Bay estuarine hydrosystem. The tidal range is dramatic within Great Bay. Average depth of the embayment is 2.7 metres (8.9 ft) with channels extending to 17.7 metres (58.1 ft). The water surface of Great Bay covers 8.9 square miles (23.1 km²) at high tide and 4.2 square miles (10.9 km²) at low tide, leaving greater than 50% of the bay exposed at low tide.
, meets the Atlantic Ocean
at the mouth of the Piscataqua, between New Castle, New Hampshire
and Kittery, Maine
. Tides carry salt water into the estuary twice daily from the Atlantic. Here it mingles with the fresh water influence from the various rivers that empty into Great Bay. It is one of the largest estuaries on the Atlantic Coast and at 10 miles (16.1 km) inland is one of the most recessed.
Approximately 14,000 years ago, following the melting of the glaciers, the Great Bay estuary was formed. The glacial melt waters contributed to rising ocean waters, which flooded the land and filled the river valleys that make up Great Bay today.
There are five very different water-dominated habitats that make up the Great Bay. In order of abundance they are: eelgrass
meadows, mudflat
s, salt marsh
, channel bottom, and rocky intertidal
. These habitats are home to 162 bird, fish and plant species (23 of which are threatened or endangered), countless invertebrate species and even the occasional harbor seal.
Eelgrass is one of a very few underwater marine flowering plants. It has many functions in the estuarine system. The eelgrass community provides habitat for several organisms, especially the young of fish and invertebrates. Eelgrass roots help stabilize the bottom sediments. Eelgrass plants help maintain water quality and clarity by filtering the water allowing sediments to settle and then using the excess nutrients for growth.
More than half of Great Bay is exposed as mudflats at low tide. Worms, soft-shelled clams, mud snails, green crabs, wading birds, horseshoe crabs and many other animals utilize the extensive mudflat habitat for feeding, reproduction and protection from predators.
The channel bottom habitat provides a place for fish and invertebrates to move to at low tide. It is also the preferred habitat for oysters, a highly specialized animal that only live in estuaries.
Rocky intertidal habitat provides firm anchorage for seaweeds, barnacles, and ribbed mussels. Each winter, much of the standing crop of seaweeds becomes entrapped in ice. When the ice begins to break up in spring, the seaweeds are torn from the rocks and enter into the detrital cycle.
were the first to live on the shores of Great Bay. They survived on the abundant fish, shellfish, waterfowl and mammals that lived in and around the estuary.
The early 17th century brought the arrival of European settlers who also took advantage of the seemingly endless supply of resources. They used the bay to transport their harvests. The tidal influence was the perfect way to move goods without much human or animal effort. A simple, flat-bottomed boat, the gundalow
, was developed to make use of the tides and carry heavy loads in shallow waters.
Gundalows transported many types of freight. Saltmarsh hay, lumber, fish, clay and textiles were just a few of the cargoes. Salt hay harvested along the shores was used as food and bedding for horses and cattle. Sawmill
s located along the tidal rivers produced lumber that was exported to other U.S. ports. Core drilling shows evidence that the whole bay was once covered by several inches of sawdust from the dozens of sawmills around the bay's shores. The lumber produced also fueled the shipbuilding business along the Piscataqua River until steam-powered steel vessels became cheaper to build. Brickyard
s also dotted the shores of Great Bay and its tributaries. Blue marine clay was harvested from along the estuary shores and made into bricks that were used to build locally and all around New England. Cotton mills were an important part of the Industrial Revolution. Wherever gundalow ports were, mills were built.
The estuary continued to be heavily used for commercial purposes throughout the nineteenth and early 20th centuries. Gristmill
s and tanneries
on the rivers of the estuary contributed significantly to the chemical pollution until the mid 20th century. When the Greek entrepreneur Aristotle Onassis
proposed building the Olympic Oil Refinery in the town of Durham
along the shore of Great Bay in 1973, local citizens mobilized and by exercising their right to "home rule", defeated the proposal by a margin of nine to one.
, of which Great Bay is a branch, is often considered by scientists and the public alike as one of the most pristine marine environments on the East Coast of the United States
. As a result of its water circulation patterns and the combined productivity of its seaweed
, salt marsh grasses, and phytoplankton
, the Gulf of Maine is also one of the world's most productive water bodies. Historically, it has been a source of livelihood for tens of thousands of commercial fishermen. More recently, recreation- and tourism-related employment has been recognized as a major contributor to the region's economy.
occupies several portions of the bay's shoreline and protects numerous land and water areas around the estuary, including salt marshes, rocky shores, bluffs, woodlands, open fields, and riverine systems and tidal waters.
Strafford County, New Hampshire
-Demographics:As of the census of 2000, there were 112,233 people, 42,581 households, and 27,762 families residing in the county. The population density was 304 people per square mile . There were 45,539 housing units at an average density of 124 per square mile...
and Rockingham
Rockingham County, New Hampshire
-Demographics:As of the census of 2000, there were 277,359 people, 104,529 households, and 74,320 families residing in the county. The population density was 399 people per square mile . There were 113,023 housing units at an average density of 163 per square mile...
counties in eastern New Hampshire
New Hampshire
New Hampshire is a state in the New England region of the northeastern United States of America. The state was named after the southern English county of Hampshire. It is bordered by Massachusetts to the south, Vermont to the west, Maine and the Atlantic Ocean to the east, and the Canadian...
, United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
. The bay occupies over 6000 acres (24.3 km²), not including its several tidal river tributaries. Its outlet is at Hilton Point in Dover, New Hampshire
Dover, New Hampshire
Dover is a city in Strafford County, New Hampshire, in the United States of America. The population was 29,987 at the 2010 census, the largest in the New Hampshire Seacoast region...
, where waters from the bay flow into the Piscataqua River
Piscataqua River
The Piscataqua River, in the northeastern United States, is a long tidal estuary formed by the confluence of the Salmon Falls and Cocheco rivers...
, thence proceeding southeast to the Atlantic Ocean
Atlantic Ocean
The Atlantic Ocean is the second-largest of the world's oceanic divisions. With a total area of about , it covers approximately 20% of the Earth's surface and about 26% of its water surface area...
near Portsmouth
Portsmouth, New Hampshire
Portsmouth is a city in Rockingham County, New Hampshire in the United States. It is the largest city but only the fourth-largest community in the county, with a population of 21,233 at the 2010 census...
. The northern end of the bay, near its outlet, is referred to as Little Bay.
Geography
Located within the Gulf of MaineGulf of Maine
The Gulf of Maine is a large gulf of the Atlantic Ocean on the east coast of North America.It is delineated by Cape Cod at the eastern tip of Massachusetts in the southwest and Cape Sable at the southern tip of Nova Scotia in the northeast. It includes the entire coastlines of the U.S...
watershed, the Great Bay Estuary is a drowned river valley composed of high-energy tidal waters, deep channels and fringing mudflats. The entire estuary extends inland from the mouth of the Piscataqua River
Piscataqua River
The Piscataqua River, in the northeastern United States, is a long tidal estuary formed by the confluence of the Salmon Falls and Cocheco rivers...
between Kittery, Maine
Kittery, Maine
Kittery is a town in York County, Maine, United States. The population was 9,543 at the 2000 census. Home to the Portsmouth Naval Shipyard on Seavey's Island, Kittery includes Badger's Island, the seaside district of Kittery Point, and part of the Isles of Shoals...
, and New Castle, New Hampshire
New Castle, New Hampshire
New Castle is a town in Rockingham County, New Hampshire, United States. The population was 968 at the 2010 census. It is the smallest town in New Hampshire, and the only one located entirely on islands. It is home to Fort Constitution Historic Site, Fort Stark Historic Site, and the New Castle...
through Little Bay into Great Bay proper at Furber Strait, a distance of 12 miles (19.3 km). The Great Bay Estuary is a tidally-dominated system and is the drainage confluence of three major rivers, the Lamprey
Lamprey River
The Lamprey River is a 50.2 mile long river in southeastern New Hampshire, the United States. It rises in Meadow Lake in Northwood, and flows south, then generally east past Raymond, Epping, Lee and finally Newmarket...
, Squamscott
Squamscott River
The Squamscott River is a tidal river in Rockingham County, southeastern New Hampshire, in the United States. It rises at Exeter, fed by the Exeter River...
, and Winnicut
Winnicut River
The Winnicut River is a 9.1 mile long river in the Seacoast region of New Hampshire in the United States. It is the major southeastern tributary of Great Bay, an estuary connected by way of the tidal Piscataqua River to the Atlantic Ocean....
. Four additional rivers flow into the system between Furber Strait and the open coast: the Cocheco, Salmon Falls
Salmon Falls River
The Salmon Falls River is a tributary of the Piscataqua River in the U.S. states of Maine and New Hampshire. It rises at Great East Lake and flows south-southeast for approximately , forming the border between Maine and New Hampshire....
, Bellamy
Bellamy River
The Bellamy River, in Strafford County, southeastern New Hampshire, is a tributary of the Piscataqua River about long. It rises in Swains Lake in Barrington, west of Dover...
, and Oyster
Oyster River
Oyster River can refer to:* Oyster River , USA* Oyster River , USA* Oyster River , Canada* The community of Oyster River, British Columbia, Canada...
rivers.
The Piscataqua River is an ocean-dominated system extending from the Gulf of Maine at Portsmouth Harbor and forming the border of New Hampshire and Maine to the fork of its tributaries, the Salmon Falls and Cocheco rivers. These rivers, several small creeks and their tributaries and ocean water from the Gulf of Maine create the Great Bay estuarine hydrosystem. The tidal range is dramatic within Great Bay. Average depth of the embayment is 2.7 metres (8.9 ft) with channels extending to 17.7 metres (58.1 ft). The water surface of Great Bay covers 8.9 square miles (23.1 km²) at high tide and 4.2 square miles (10.9 km²) at low tide, leaving greater than 50% of the bay exposed at low tide.
Natural heritage
The Great Bay Estuary, when counting the entire tidal system including the Piscataqua RiverPiscataqua River
The Piscataqua River, in the northeastern United States, is a long tidal estuary formed by the confluence of the Salmon Falls and Cocheco rivers...
, meets the Atlantic Ocean
Atlantic Ocean
The Atlantic Ocean is the second-largest of the world's oceanic divisions. With a total area of about , it covers approximately 20% of the Earth's surface and about 26% of its water surface area...
at the mouth of the Piscataqua, between New Castle, New Hampshire
New Castle, New Hampshire
New Castle is a town in Rockingham County, New Hampshire, United States. The population was 968 at the 2010 census. It is the smallest town in New Hampshire, and the only one located entirely on islands. It is home to Fort Constitution Historic Site, Fort Stark Historic Site, and the New Castle...
and Kittery, Maine
Kittery, Maine
Kittery is a town in York County, Maine, United States. The population was 9,543 at the 2000 census. Home to the Portsmouth Naval Shipyard on Seavey's Island, Kittery includes Badger's Island, the seaside district of Kittery Point, and part of the Isles of Shoals...
. Tides carry salt water into the estuary twice daily from the Atlantic. Here it mingles with the fresh water influence from the various rivers that empty into Great Bay. It is one of the largest estuaries on the Atlantic Coast and at 10 miles (16.1 km) inland is one of the most recessed.
Approximately 14,000 years ago, following the melting of the glaciers, the Great Bay estuary was formed. The glacial melt waters contributed to rising ocean waters, which flooded the land and filled the river valleys that make up Great Bay today.
There are five very different water-dominated habitats that make up the Great Bay. In order of abundance they are: eelgrass
Zostera
Zostera is a small genus of widely distributed seagrass, commonly called marine eelgrass or simply eelgrass . The genus Zostera contains sixteen species.-Ecology:Zostera is found on sandy substrates or in estuaries submerged or partially floating...
meadows, mudflat
Mudflat
Mudflats or mud flats, also known as tidal flats, are coastal wetlands that form when mud is deposited by tides or rivers. They are found in sheltered areas such as bays, bayous, lagoons, and estuaries. Mudflats may be viewed geologically as exposed layers of bay mud, resulting from deposition of...
s, salt marsh
Salt marsh
A salt marsh is an environment in the upper coastal intertidal zone between land and salt water or brackish water, it is dominated by dense stands of halophytic plants such as herbs, grasses, or low shrubs. These plants are terrestrial in origin and are essential to the stability of the salt marsh...
, channel bottom, and rocky intertidal
Intertidal zone
The intertidal zone is the area that is above water at low tide and under water at high tide . This area can include many different types of habitats, with many types of animals like starfish, sea urchins, and some species of coral...
. These habitats are home to 162 bird, fish and plant species (23 of which are threatened or endangered), countless invertebrate species and even the occasional harbor seal.
Eelgrass is one of a very few underwater marine flowering plants. It has many functions in the estuarine system. The eelgrass community provides habitat for several organisms, especially the young of fish and invertebrates. Eelgrass roots help stabilize the bottom sediments. Eelgrass plants help maintain water quality and clarity by filtering the water allowing sediments to settle and then using the excess nutrients for growth.
More than half of Great Bay is exposed as mudflats at low tide. Worms, soft-shelled clams, mud snails, green crabs, wading birds, horseshoe crabs and many other animals utilize the extensive mudflat habitat for feeding, reproduction and protection from predators.
The channel bottom habitat provides a place for fish and invertebrates to move to at low tide. It is also the preferred habitat for oysters, a highly specialized animal that only live in estuaries.
Rocky intertidal habitat provides firm anchorage for seaweeds, barnacles, and ribbed mussels. Each winter, much of the standing crop of seaweeds becomes entrapped in ice. When the ice begins to break up in spring, the seaweeds are torn from the rocks and enter into the detrital cycle.
Cultural history
Native AmericansNative Americans in the United States
Native Americans in the United States are the indigenous peoples in North America within the boundaries of the present-day continental United States, parts of Alaska, and the island state of Hawaii. They are composed of numerous, distinct tribes, states, and ethnic groups, many of which survive as...
were the first to live on the shores of Great Bay. They survived on the abundant fish, shellfish, waterfowl and mammals that lived in and around the estuary.
The early 17th century brought the arrival of European settlers who also took advantage of the seemingly endless supply of resources. They used the bay to transport their harvests. The tidal influence was the perfect way to move goods without much human or animal effort. A simple, flat-bottomed boat, the gundalow
Gundalow
A gundalow is a type of flat bottom cargo vessel once common in Maine and New England rivers. Up to long, they characteristically employed tidal currents for propulsion, shipping a single lateen sail to harness favorable winds....
, was developed to make use of the tides and carry heavy loads in shallow waters.
Gundalows transported many types of freight. Saltmarsh hay, lumber, fish, clay and textiles were just a few of the cargoes. Salt hay harvested along the shores was used as food and bedding for horses and cattle. Sawmill
Sawmill
A sawmill is a facility where logs are cut into boards.-Sawmill process:A sawmill's basic operation is much like those of hundreds of years ago; a log enters on one end and dimensional lumber exits on the other end....
s located along the tidal rivers produced lumber that was exported to other U.S. ports. Core drilling shows evidence that the whole bay was once covered by several inches of sawdust from the dozens of sawmills around the bay's shores. The lumber produced also fueled the shipbuilding business along the Piscataqua River until steam-powered steel vessels became cheaper to build. Brickyard
Brickyard
A brickyard is a place or yard where the earthen building material called bricks are made, fired, and stored, or sometimes sold or otherwise distributed from.-See also:...
s also dotted the shores of Great Bay and its tributaries. Blue marine clay was harvested from along the estuary shores and made into bricks that were used to build locally and all around New England. Cotton mills were an important part of the Industrial Revolution. Wherever gundalow ports were, mills were built.
The estuary continued to be heavily used for commercial purposes throughout the nineteenth and early 20th centuries. Gristmill
Gristmill
The terms gristmill or grist mill can refer either to a building in which grain is ground into flour, or to the grinding mechanism itself.- Early history :...
s and tanneries
Tanning
Tanning is the making of leather from the skins of animals which does not easily decompose. Traditionally, tanning used tannin, an acidic chemical compound from which the tanning process draws its name . Coloring may occur during tanning...
on the rivers of the estuary contributed significantly to the chemical pollution until the mid 20th century. When the Greek entrepreneur Aristotle Onassis
Aristotle Onassis
Aristotle Sokratis Onassis , commonly called Ari or Aristo Onassis, was a prominent Greek shipping magnate.- Early life :Onassis was born in Karatass, a suburb of Smyrna to Socrates and Penelope Onassis...
proposed building the Olympic Oil Refinery in the town of Durham
Durham, New Hampshire
As of the census of 2000, there were 12,664 people, 2,882 households, and 1,582 families residing in the town. The population density was 565.5 people per square mile . There were 2,923 housing units at an average density of 130.5 per square mile...
along the shore of Great Bay in 1973, local citizens mobilized and by exercising their right to "home rule", defeated the proposal by a margin of nine to one.
Regional significance
The Gulf of MaineGulf of Maine
The Gulf of Maine is a large gulf of the Atlantic Ocean on the east coast of North America.It is delineated by Cape Cod at the eastern tip of Massachusetts in the southwest and Cape Sable at the southern tip of Nova Scotia in the northeast. It includes the entire coastlines of the U.S...
, of which Great Bay is a branch, is often considered by scientists and the public alike as one of the most pristine marine environments on the East Coast of the United States
East Coast of the United States
The East Coast of the United States, also known as the Eastern Seaboard, refers to the easternmost coastal states in the United States, which touch the Atlantic Ocean and stretch up to Canada. The term includes the U.S...
. As a result of its water circulation patterns and the combined productivity of its seaweed
Seaweed
Seaweed is a loose, colloquial term encompassing macroscopic, multicellular, benthic marine algae. The term includes some members of the red, brown and green algae...
, salt marsh grasses, and phytoplankton
Phytoplankton
Phytoplankton are the autotrophic component of the plankton community. The name comes from the Greek words φυτόν , meaning "plant", and πλαγκτός , meaning "wanderer" or "drifter". Most phytoplankton are too small to be individually seen with the unaided eye...
, the Gulf of Maine is also one of the world's most productive water bodies. Historically, it has been a source of livelihood for tens of thousands of commercial fishermen. More recently, recreation- and tourism-related employment has been recognized as a major contributor to the region's economy.
Great Bay Reserve
The Great Bay National Estuarine Research ReserveGreat Bay National Estuarine Research Reserve
The Great Bay National Estuarine Research Reserve encompasses a diversity of land and water areas around Great Bay, an estuary in southeastern New Hampshire...
occupies several portions of the bay's shoreline and protects numerous land and water areas around the estuary, including salt marshes, rocky shores, bluffs, woodlands, open fields, and riverine systems and tidal waters.