The Concord River is a U.S. Geological Survey. National Hydrography Dataset high-resolution flowline data
The National Map
, accessed October 3, 2011

tributary A tributary, or affluent, is a stream or river that flows into a larger stream or main stem (or parent) river or a lake. A tributary does not flow directly into a sea or ocean. Tributaries and the main stem river drain the surrounding drai ...

of the

Merrimack River The Merrimack River (or Merrimac River, an occasional earlier spelling) is a river in the northeastern United States. It rises at the confluence of the Pemigewasset and Winnipesaukee rivers in Franklin, New Hampshire, flows southward into Mas ...

in eastern

Massachusetts Massachusetts (Massachusett: ''Muhsachuweesut Massachusett_writing_systems.html" ;"title="nowiki/> məhswatʃəwiːsət.html" ;"title="Massachusett writing systems">məhswatʃəwiːsət">Massachusett writing systems">məhswatʃəwiːsət'' En ...

in the United States. The river drains a small rural and suburban region northwest of

Boston Boston (), officially the City of Boston, is the state capital and most populous city of the Commonwealth of Massachusetts, as well as the cultural and financial center of the New England region of the United States. It is the 24th- mo ...

. One of the most famous small rivers in U.S. history, it was the scene of an important early

battle A battle is an occurrence of combat in warfare between opposing military units of any number or size. A war usually consists of multiple battles. In general, a battle is a military engagement that is well defined in duration, area, and for ...

of the

American Revolutionary War The American Revolutionary War (April 19, 1775 – September 3, 1783), also known as the Revolutionary War or American War of Independence, was a major war of the American Revolution. Widely considered as the war that secured the independence of t ...

and was the subject of a famous 19th-century book by

Henry David Thoreau Henry David Thoreau (July 12, 1817May 6, 1862) was an American naturalist, essayist, poet, and philosopher. A leading transcendentalist, he is best known for his book ''Walden'', a reflection upon simple living in natural surroundings, and h ...

Description and early history

The river begins in Middlesex County, formed by the confluence of the

Sudbury Sudbury may refer to: Places Australia * Sudbury Reef, Queensland Canada * Greater Sudbury, Ontario (official name; the city continues to be known simply as Sudbury for most purposes) ** Sudbury (electoral district), one of the city's federal el ...

and Assabet rivers at Egg Rock, near the

Concord Concord may refer to: Meaning "agreement" * Pact or treaty, frequently between nations (indicating a condition of harmony) * Harmony, in music * Agreement (linguistics), a change in the form of a word depending on grammatical features of other ...

town center. It flows generally north, from eastern Concord (along the northwestern edge of the

Boston metropolitan area Greater Boston is the metropolitan region of New England encompassing the municipality of Boston (the capital of the U.S. state of Massachusetts and the most populous city in New England) and its surrounding areas. The region forms the northern ...

), joining the Merrimack River from the south on the eastern side of Lowell. It is a gently flowing stream with little variation in topography along most of its route. Its

drainage basin A drainage basin is an area of land where all flowing surface water converges to a single point, such as a river mouth, or flows into another body of water, such as a lake or ocean. A basin is separated from adjacent basins by a perimeter, ...

stretches into Worcester County and includes 36 towns within Massachusetts. Native Americans called it the ''Musketaquid'' or "grass-grown" river because of its sluggish waters abound in aquatic or semi-aquatic vegetation and its banks are fringed with wild grasses and sedges which stretch for miles along both sides of this placid stream. This creates a good environment for a variety of fish, including

bass Bass or Basses may refer to: Fish * Bass (fish), various saltwater and freshwater species Music * Bass (sound), describing low-frequency sound or one of several instruments in the bass range: ** Bass (instrument), including: ** Acoustic bass gui ...

shad The Alosinae, or the shads,Alosinae
alewife (river herring), pickerel,

carp Carp are various species of oily freshwater fish from the family Cyprinidae, a very large group of fish native to Europe and Asia. While carp is consumed in many parts of the world, they are generally considered an invasive species in parts of ...

, and

American eel The American eel (''Anguilla rostrata'') is a facultative catadromous fish found on the eastern coast of North America. Freshwater eels are fish belonging to the elopomorph superorder, a group of phylogenetically ancient teleosts. The Amer ...

. Native Americans wove sticks in intricate designs to trap Alewives and other migrating fish at the mouths of rivers throughout this region. By 1635, settlers from England began to arrive, and they gave the river its present name. On April 19, 1775, the Old North Bridge over the river in the town of Concord was famously the scene of the Battle of Concord (on the same day when the first shots of the Revolutionary War were fired at nearby

Lexington Lexington may refer to: Places England * Laxton, Nottinghamshire, formerly Lexington Canada * Lexington, a district in Waterloo, Ontario United States * Lexington, Kentucky, the largest city with this name * Lexington, Massachusetts, the oldes ...

). The current version of the bridge (a reproduction) is preserved by the

National Park Service The National Park Service (NPS) is an agency of the United States federal government within the U.S. Department of the Interior that manages all national parks, most national monuments, and other natural, historical, and recreational properti ...

wrote his first book, '' A Week on the Concord and Merrimack Rivers'', in 1849 while living at nearby Walden Pond. His book recounted a seven-day boat trip on the rivers with his brother John, who had since died. Thoreau recounted his exploration of the natural beauty of the river, and his accompanying thoughts on such eternal themes as truth, poetry, travel, and friendship. Despite the growth of the suburbs in the vicinity of the river, it remains a popular canoeing destination today. The last mile of the river in Lowell is serious class 3+/4 whitewater.

Dams cause fish population to decrease

Dams were built along the Concord River to increase crop production and also to provide a source of power for operating mills. By the 19th century, the native population of shad and alewife became extinct, because the dams prevented the mature fish from returning upstream to spawn. Alewife and other anadromous fish are migratory. They hatch in freshwater, make their way to the sea to grow, then return as adults to freshwater to

spawn Spawn or spawning may refer to: * Spawn (biology), the eggs and sperm of aquatic animals Arts, entertainment, and media * Spawn (character), a fictional character in the comic series of the same name and in the associated franchise ** '' Spawn: A ...

, usually near where they had hatched. This instinct is imprinted within the fish when it is born. So, when the route upstream became blocked, the cycle was broken. The Faulkner Dam in North Billerica is just one of many blockages that caused the alewife population to collapse on the Concord River. At this point, water was diverted north to Lowell and south to Charlestown to run the Middlesex Canal.

Effects of pollution

During the 19th century, the Concord River was near the heart of the US

Industrial Revolution The Industrial Revolution was the transition to new manufacturing processes in Great Britain, continental Europe, and the United States, that occurred during the period from around 1760 to about 1820–1840. This transition included going f ...

Textile Textile is an Hyponymy and hypernymy, umbrella term that includes various Fiber, fiber-based materials, including fibers, yarns, Staple (textiles)#Filament fiber, filaments, Thread (yarn), threads, different #Fabric, fabric types, etc. At f ...

paper Paper is a thin sheet material produced by mechanically or chemically processing cellulose fibres derived from wood, rags, grasses or other vegetable sources in water, draining the water through fine mesh leaving the fibre evenly distribu ...

, tanning, and

mining Mining is the extraction of valuable minerals or other geological materials from the Earth, usually from an ore body, lode, vein, seam, reef, or placer deposit. The exploitation of these deposits for raw material is based on the econom ...

industries all emerged during this period. Industrial wastes were dumped into the river, along with untreated sewage and other organic waste. Industrial development within the watershed peaked in the 1920s. The early 1960s saw an increase in the number of chemical and metal firms, many supporting the

electronics industry The electronics industry is the economic sector that produces electronic devices. It emerged in the 20th century and is today one of the largest global industries. Contemporary society uses a vast array of electronic devices built-in automated or ...

within the

metropolitan area. By the 1960s, the Merrimack River was considered one of the top ten most polluted waterways in America. The Concord River empties into the Merrimack River. The passage of the

Clean Water Act The Clean Water Act (CWA) is the primary federal law in the United States governing water pollution. Its objective is to restore and maintain the chemical, physical, and biological integrity of the nation's waters; recognizing the responsibiliti ...

in 1972 signaled the beginning of US efforts to improve the quality of its waterways. The act imposed stricter controls on point source discharges into rivers and other navigable waters. This eventually led to the installation of three wastewater treatment plants on the banks of the Concord River: one in

and two in Billerica. These plants have helped to prevent subsequent damage to the river ecosystem when they were able to operate within federally mandated limits. Pollutants such as heavy metals and PCBs remain trapped in the sediment. Throughout much of the Sudbury River and downstream into the Concord River, fish consumption is banned due to mercury-laden sediments from the Nyanza Superfund site and other sources.

Perchlorate A perchlorate is a chemical compound containing the perchlorate ion, . The majority of perchlorates are commercially produced salts. They are mainly used as oxidizers for pyrotechnic devices and to control static electricity in food packaging. ...

was detected in the Concord River in August 2004. Initially, it was believed that explosives used in road and building construction were the source of this pollutant. However, an investigation by the town of Billerica eventually determined that the source was a local company that produced surgical and medical materials. The company was using 220 gallons per month of

perchloric acid Perchloric acid is a mineral acid with the formula H Cl O4. Usually found as an aqueous solution, this colorless compound is a stronger acid than sulfuric acid, nitric acid and hydrochloric acid. It is a powerful oxidizer when hot, but aqueo ...

in a

bleaching Bleach is the generic name for any chemical product that is used industrially or domestically to remove color (whitening) from a fabric or fiber or to clean or to remove stains in a process called bleaching. It often refers specifically, to ...

process, and rinse water was being discharged into the sewage system. After the company was identified, it voluntarily shut down until ion exchange equipment could be installed in accordance with environmental guidelines. In May 2007, Billerica was the subject of legal action and forced to pay a $250,000 penalty for discharging pollutants into the Concord River. The action was brought by the U.S. Environmental Protection Agency (EPA) and the

Massachusetts Department of Environmental Protection The Massachusetts Department of Environmental Protection is an agency in the Executive Office of Energy and Environmental Affairs of the Commonwealth of Massachusetts, responsible for protecting the environment in the state. Its areas of resp ...

(MassDEP) because the town of Billerica exceeded allowable effluent limits for

phosphorus Phosphorus is a chemical element with the symbol P and atomic number 15. Elemental phosphorus exists in two major forms, white phosphorus and red phosphorus, but because it is highly reactive, phosphorus is never found as a free element on Ea ...

, fecal coliform bacteria, pH, and

ammonia Ammonia is an inorganic compound of nitrogen and hydrogen with the formula . A stable binary hydride, and the simplest pnictogen hydride, ammonia is a colourless gas with a distinct pungent smell. Biologically, it is a common nitrogenous ...

nitrogen. The town was also charged with failing to submit discharge monitoring reports, failing to comply with monitoring requirements, and failing to submit infiltration and inflow reporting. According to the EPA, Billerica's discharges of phosphorus created an overabundance of nutrients, which damaged the river by stimulating excessive aquatic plant growth.

Diadromous fish recovery effort

In May 2000, the U.S. Fish and Wildlife Service, the Massachusetts Riverways Program, and volunteers from the

Sudbury Valley Trustees Sudbury Valley Trustees (SVT) is a regional open space land trust headquartered at Wolbach Farm in Sudbury, Massachusetts. Mission The SVT mission is to conserve land and protect wildlife habitat in the Concord, Assabet, and Sudbury river wate ...

(SVT) released 7,000 adult alewife (river herring) into the Concord River. They were transferred from the

Nemasket River The Nemasket or Namasket River is a small river in southeastern Massachusetts. It flows north U.S. Geological Survey. National Hydrography Dataset high-resolution flowline dataThe National Map accessed April 1, 2011 from Assawompset Pond in Lakev ...

so that they could lay their eggs and spawn upstream. This imprinted the young alewives with the Concord as their new home river. The experiment did not succeed, as too few fish returned to the base of the first dam on the Concord River. A feasibility study published in 2016 is again exploring steps necessary for returning diadromous fish to the Concord River, and farther upstream, to the Sudbury and Assabet Rivers. Anadromous describes species that live in salt water but lay eggs in fresh water - such as alewives and shad; diadromous is a larger grouping which includes species that mature in fresh water but return to salt water to lay eggs - such as eels.

References

External links