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The Saw Mill River is a tributary of the Hudson River in Westchester County, New York, United States. It flows from an unnamed pond north of Chappaqua to
Getty Square Getty Square is the name for downtown Yonkers, New York, centered on the public square. Getty Square is the civic center, central business district, and transit hub of the City of Yonkers. A dense and growing residential area, it is located ...
in Yonkers, where it empties into the Hudson as that river's southernmost tributary. It is the only major stream in southern Westchester County to drain into the Hudson instead of
Long Island Sound Long Island Sound is a marine sound and tidal estuary of the Atlantic Ocean. It lies predominantly between the U.S. state of Connecticut to the north and Long Island in New York to the south. From west to east, the sound stretches from the Eas ...
. It drains an area of , most of it heavily developed suburbia. For , it flows parallel to the
Saw Mill River Parkway The Saw Mill River Parkway (also known as the Saw Mill Parkway or the Saw Mill) is a north–south parkway that extends for through Westchester County, New York, in the United States. It begins at the border between Westchester County and the Bro ...
, a commuter artery, an association that has been said to give the river an "identity crisis." The watershed was settled by the Dutch in the 17th century. The land was long owned by
Frederick Philipse I Frederick Philipse (born Frederick Flypsen;Appleton, W.S. ''The Heraldic Journal, Recording the Amorial Bearings and Genealogies of American Families'', Wiggen & Lunt, Boston, 1867 1626 in Bolsward, Netherlands – December 23, 1702), first Lord ...
and his descendants as Philipsburg Manor, site of
Philipse Manor Hall Philipse Manor Hall State Historic Site is a historic house museum located in the Getty Square neighborhood of Yonkers, New York. Originally the family seat of Philipse Manor, it is Westchester County's second oldest standing building after th ...
, until the family lost it at the end of the American Revolution. The land along the river was later divided into multiple towns. Industry in Yonkers developed along the Saw Mill, so polluting the river by the end of the 19th century that a local poet called it a "snake-like yellow scrawl of scum". In the 1920s, the last half-mile (800 m) of the stream was routed into tunnels and
culvert A culvert is a structure that channels water past an obstacle or to a subterranean waterway. Typically embedded so as to be surrounded by soil, a culvert may be made from a pipe, reinforced concrete or other material. In the United Kingdom ...
s under downtown Yonkers, a process partially reversed in the early 21st century when it became the first major New York waterway to be daylighted. Today, the U.S. Environmental Protection Agency (EPA) rates the river's last as an impaired water body. Plastics are commonly found along the riverbank, and metals from industrial factories are found in the water in high concentrations. Nonetheless, the river is home to species such as the
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 America ...
(Anguilla rostrata), which swim upstream to mature and swim back into the Hudson and the ocean in order to breed.


Course

The Saw Mill River rises from a pond in a wooded area of the town of New Castle roughly north of Chappaqua, a west of Quaker Road State Route 120 (NY 120) and just south of Stony Hollow Road, at an elevation of above sea level. It wends and meanders past a cemetery, between hills, through a residential area of houses on large wooded
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in a generally southward direction. Just north of Marcourt Drive, its first crossing, it is impounded to create another small pond. In this area it is frequently channelized and impounded as part of the landscaping on the area's large residential
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s. After crossing under Kipp Street, it bends eastward to cross under Quaker Road. A short
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portion runs through the front yard of a large house on Quaker southeast of the intersection, after which the river flows back under Quaker and behind the houses on the west side into another impoundment, Chappaqua's Duck Pond. From its outlet it continues southeast between Quaker on its east and Douglas and Mill River roads on the west to the
Saw Mill River Parkway The Saw Mill River Parkway (also known as the Saw Mill Parkway or the Saw Mill) is a north–south parkway that extends for through Westchester County, New York, in the United States. It begins at the border between Westchester County and the Bro ...
. Just west of the Chappaqua train station, it turns southwest to parallel both the parkway and
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's Harlem Line as both cross into the town of Mount Pleasant. At this point the river is at in elevation, a loss of from its source. Just south of the town line, it receives
Tertia Brook Tertia is an ancient Roman name for women, in Latin it denotes a third daughter of a family People * Aemilia Tertia (circa 230-163 BC), wife of Scipio Africanus * Junia Tertia (circa 60 BC-22 AD), daughter of Servilia Caepionis * Mucia Tertia (1st ...
, its first named tributary, from the east. A mile past the town line, the river and its eponymous parkway pass the village of Pleasantville to the east. There the river crosses under the parkway to flow on its west, then crosses and recrosses at the Pleasantville Road ( State Route 117) exit. Both make a long turn to the southeast and then back to the southwest around
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, where it receives Nanny Hagen Brook from the east, before crossing back to the parkway's west in the
flood plain A floodplain or flood plain or bottomlands is an area of land adjacent to a river which stretches from the banks of its channel to the base of the enclosing valley walls, and which experiences flooding during periods of high discharge.Goudi ...
around the base of the hills as road, river and rail pass the unincorporated hamlets of Thornwood, and
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, where the Harlem Line turns to the south. Just east of the
Taconic State Parkway The Taconic State Parkway (often called the Taconic or the TSP and known administratively as New York State Route 987G or NY 987G) is a Parkways in New York State, parkway between Kensico Dam and Chatham (town), New York, Chatham, the ...
, the river again crosses under the Saw Mill Parkway, then the Taconic. Shortly after that exit it crosses under Saw Mill River Road ( State Routes 9A and
100 100 or one hundred (Roman numeral: C) is the natural number following 99 and preceding 101. In medieval contexts, it may be described as the short hundred or five score in order to differentiate the English and Germanic use of "hundred" to de ...
) and some ramps to them from the interchange, then under the Saw Mill Parkway. Both turn south again, then southeast, following the eastern edge of the Pocantico Hills, joined on the west by the
North County Trailway The North County Trailway is a long paved rail trail stretching from Eastview to Baldwin Place in Westchester County, New York. It is also part of the statewide Empire State Trail. History and route The North County Trailway was constructed ...
bike path, on the right-of-way of the former
New York and Putnam Railroad The New York and Putnam Railroad, nicknamed the Old Put, was a railroad line that operated between the Bronx and Brewster in New York State. It was in close proximity to the Hudson River Railroad and New York and Harlem Railroad. All three cam ...
, known as the "Old Put". The river crosses under the parkway again to form the eastern edge of a plant nursery on Saw Mill River Road, then recrosses as the river, bike path, parkway and Saw Mill River Road all bend around the northwest corner of Eastview, where the Saw Mill drops below in elevation, a loss of since Chappaqua. A turn back to the southwest around Tarrytown Lakes County Park puts the river at the outskirts of
Elmsford Elmsford is a village in Westchester County, New York, United States. It is part of the New York metropolitan area. Roughly one mile square, the village is fully contained within the borders of the town of Greenburgh. As of the 2010 census, the ...
. There it receives
Mine Brook Mine Brook is a river in Delaware County, New York. It flows into Kortright Creek Kortright Creek is a river in Delaware County, New York. It flows into Charlotte Creek west of Davenport Center. References Rivers of New York (stat ...
from the east. Here the bike path ends amidst the dense urban development, but the parkway continues, and the two again draw close as they enter the town of
Greenburgh Greenburgh is a town in western Westchester County, New York. The population was 95,397 at the time of the 2020 census. History Greenburgh developed along the Hudson River, long the main transportation route. It was settled by northern Europeans ...
and intersect the Cross Westchester Expressway ( Interstate 287). A new bike path, the
South County Trailway The South County Trailway is a long rail trail stretching from the Putnam Trail in Van Cortlandt Park in the Bronx to the North County Trailway in East View, New York. Westchester County Parks constructed the trailway in segments beginning in 1 ...
, begins here just south of the West Main Street ( State Route 119) bridge north of the Rum Brook confluence. Past that the parkway, trailway and the Saw Mill River all turn southwest, where they intersect the
New York State Thruway {{Infobox road , state = NY , type = NYST , alternate_name = Governor Thomas E. Dewey Thruway , maint = NYSTA , map = {{maplink, frame=yes, plain=yes, frame-align=center, frame-width=290, type=line, stroke-width=2, type2=line, from2=New Yor ...
( Interstate 87) at an oblique angle. For the next mile the Thruway remains close to the river, and Saw Mill River Road, now just carrying NY 9A, returns to the corridor just east of the Thruway as well. The river then runs along the west of V. Everit Macy Park. As part of the park facilities, the Saw Mill River is impounded into Woodlands Lake, the largest impoundment on the Saw Mill River, used as a water supply by the local communities of Ardsley and
Dobbs Ferry Dobbs Ferry is a village in Westchester County, New York, United States. The population was 10,875 according to the 2010 United States Census. In 2019, its population rose to an estimated 11,027. The village of Dobbs Ferry is located in, and is a p ...
, whose northern village line is just to the south. The river runs close to the boundary between the two, as the Thruway gradually veers away to the southeast just past the Ashford Avenue bridge. Continuing south-southwest, the river along with the parkway and trailway enter
Hastings-on-Hudson Hastings-on-Hudson is a village in Westchester County located in the southwestern part of the town of Greenburgh in the state of New York, United States. It is located on the eastern bank of the Hudson River, approximately north of midtown Manha ...
, its
greenbelt A green belt is a policy and land-use zone designation used in land-use planning to retain areas of largely undeveloped, wild, or agricultural land surrounding or neighboring urban areas. Similar concepts are greenways or green wedges, which hav ...
the only major break in the village's dense suburban development. It slowly veers toward a more southerly heading, and enters the Nepera Park neighborhood of Yonkers after , just south of Farragut Parkway. Once in the neighborhood, the Saw Mill River flows through a former Yonkers water treatment plant, the other impoundment of the river. After leaving the plant, to the south of where the river entered Yonkers, the parkway and trailway diverge from the river after , to climb over the watershed divide to Tibbetts Brook. Saw Mill River Road continues to parallel its namesake. Bending to the southwest again, the Saw Mill flows in a narrow channel through an industrial and commercial area. A mile south of the parkway, it flows through the middle of the former Smith Carpet Mills site, where it finally drops to in elevation. After crossing Ashburton Avenue, the river bends around to flow briefly to the northwest under Nepperhan Avenue after crossing the
Old Croton Aqueduct The Croton Aqueduct or Old Croton Aqueduct was a large and complex water supply network, water distribution system constructed for New York City between 1837 and 1842. The great aqueduct (water supply), aqueducts, which were among the first in th ...
. It circles around War Memorial Field, giving up its remaining elevation as the Hudson River nears. The Saw Mill River turns south again past the park. After passing the towers of a large
housing project Public housing is a form of housing tenure in which the property is usually owned by a government authorities, government authority, either central or local. Although the common goal of public housing is to provide affordable housing, the d ...
to its west, it is routed into a tunnel at Chicken Island, the triangle between Nepperhan and Palisade avenues and School Street. At Van der Donck Park in downtown Yonkers, it resurfaces as it flows past
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. For its final hundred feet (30 m), it re-enters a tunnel under the train station and the tracks of the Hudson Line, after which culverts empty it into the Hudson south of Dock Street.


Watershed

The Saw Mill's
watershed Watershed is a hydrological term, which has been adopted in other fields in a more or less figurative sense. It may refer to: Hydrology * Drainage divide, the line that separates neighbouring drainage basins * Drainage basin, called a "watershe ...
is limited by the hilly topography of central Westchester County to a valley that averages wide; the only wider spots are the Mine Brook and Tarrytown Lakes subwatersheds and the river's mouth in downtown Yonkers. The highest elevation in the watershed is , reached in two locations: the summit of
Sarles Hill Sarles is a city in Cavalier and Towner counties in the State of North Dakota. The population was 16 at the 2020 census. Sarles was founded in 1905 at the end of the Great Northern railway extension north of Munich, called the "Sarles Bra ...
north of Pleasantville, and an unnamed height of land about southwest of
Buttermilk Hill Buttermilk is a fermented dairy drink. Traditionally, it was the liquid left behind after churning butter out of cultured cream. As most modern butter in western countries is not made with cultured cream but uncultured sweet cream, most mod ...
, west of Hawthorne. From source to mouth, 10% of the watershed is in New Castle, 42% in the town of Mount Pleasant, 33% in
Greenburgh Greenburgh is a town in western Westchester County, New York. The population was 95,397 at the time of the 2020 census. History Greenburgh developed along the Hudson River, long the main transportation route. It was settled by northern Europeans ...
, and 14% in Yonkers. 63% of the watershed consists of dense urban or less dense suburban
land development Land development is the alteration of landscape in any number of ways such as: * Changing landforms from a natural or semi-natural state for a purpose such as agriculture or housing * Subdividing real estate into lots, typically for the purpose ...
, 34% forest, and 1% agricultural. The woodlands buffering the river and the
South County Trailway The South County Trailway is a long rail trail stretching from the Putnam Trail in Van Cortlandt Park in the Bronx to the North County Trailway in East View, New York. Westchester County Parks constructed the trailway in segments beginning in 1 ...
is one of the few significant areas of open space in the county south of I-287. Some 110,000 people live in the Saw Mill River's watershed, in communities varying from small villages to Yonkers, New York's fourth-largest city. This is 12% of the county's total, on 6% of its area. The watershed's population density varies from 1,000 per square mile around the headwaters at Chappaqua to 10,000 around the mouth. It averages to 4,151 per square mile, twice that of the county and ten times the density for the state. On the north, the Saw Mill watershed is bordered by the watersheds of Gedney Brook and the Kisco River, both of which drain into New Croton Reservoir on the Croton River, one of several large reservoirs in that watershed that are part of New York City's water supply system. On the northeast, the adjacent watersheds drain into
Kensico Reservoir The Kensico Reservoir is a reservoir spanning the towns of Armonk ( North Castle) and Valhalla ( Mount Pleasant), New York, located 3 miles (5 km) north of White Plains. It was formed by the original earth and gravel Kensico Dam constructed in 18 ...
, another that supplies the city. Moving south, the next watersheds are tributaries of the Bronx River, then Yonkers' Grassy Sprain Reservoir and finally Tibbetts Brook. To its west in the narrow strip between the Saw Mill and the Hudson are the
Pocantico River The Pocantico River is a tributary of the Hudson River in western central Westchester County, New York, United States. It rises from Echo Lake, in the town of New Castle south of the hamlet of Millwood, and flows generally southwest past Briarc ...
and
Sheldon Brook Sheldon may refer to: * Sheldon (name), a given name and a surname, and a list of people with the name Places Australia * Sheldon, Queensland *Sheldon Forest, New South Wales United Kingdom *Sheldon, Derbyshire, England *Sheldon, Devon, England * ...
watersheds at the north end of the watershed, and those of unnamed shorter streams at the south.


History


Pre-colonial

The Saw Mill River, then known as the Nepperhan River, acted as a boundary between the Manhattan Indians and the Weckquaesgeeks, members of the Algonquian family who fished the region's streams and lakes with rods and nets. The Manhattans occupied present-day New York City north to the river, while the Weckquaesgeeks occupied the land from the river north to the Pocantico River. The Manhattans' principal village, Nepperamack, was on the site of present-day Yonkers where the Saw Mill River discharges into the Hudson River. The Weckquaesgeeks settled the site of today's Dobbs Ferry, and on the river's banks west of White Plains.


Colonial period

In 1639, the
Dutch West India Company The Dutch West India Company ( nl, Geoctrooieerde Westindische Compagnie, ''WIC'' or ''GWC''; ; en, Chartered West India Company) was a chartered company of Dutch merchants as well as foreign investors. Among its founders was Willem Usselincx ( ...
acquired from the Manhattans the area that would become Yonkers. Seven years later, Dutch settler Adriaen van der Donck was granted part of this land, including the southern section of what he named the ''Saeck-kill'', today's Saw Mill River. His estate was called Colen Donck, for "Donck's colony". He built a sawmill and a gristmill on the Saeck-kill. After his death, his widow gradually sold the land. In the 1670s, part of Donck's land passed to Frederick Philipse, who was rewarded with , including the lower river, for declaring his loyalty to the new British rulers of New Netherlands. Philipse named the manor Philipsborough and ran it as a quasi-feudal farm, hiring tenants to work the land. Around 1682, he built
Philipse Manor Hall Philipse Manor Hall State Historic Site is a historic house museum located in the Getty Square neighborhood of Yonkers, New York. Originally the family seat of Philipse Manor, it is Westchester County's second oldest standing building after th ...
, a mansion along the Saw Mill River that is today a National Historic Landmark. When Philipse died around 1702, the manor was divided between his son Adolph and grandson Frederick II. In 1750, his great-grandson Frederick III inherited the whole property and moved from his New York City townhouse to the manor hall, previously used as the family's summer home. Frederick sat in the Colonial Assembly, where he was a strong supporter of the British government that had given his family everything it owned, but he was primarily interested in managing the land. He improved the manor hall and worked to attract tenant farmers to the land. The family was known for its relaxed approach to its tenants, and the farm was very profitable. Commercially navigable only at its mouth, the Saw Mill River itself was useless as a way to bring crops to market, limiting settlement further upriver. Nevertheless, the roots of present-day communities along the river were established during the colonial era. In 1695, a land agent named Isaac See settled at the north bound of Philipse Manor, in the flat land between a bend in the river. Other farmers came to the area, and the settlement ultimately became today's village of Pleasantville. By 1704, the area that is today Elmsford, New York was known as Storm's Bridge, after Abraham Storm, who established a tavern at the junction of the Saw Mill River and Tarrytown roads (today routes 9A and
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) that is the center of that village today. In 1719, one of the Philipse tenant farmers, William Hammond, built
his house ''His House'' is a 2020 horror thriller film written and directed by Remi Weekes from a story by Felicity Evans and Toby Venables. It stars Wunmi Mosaku, Sope Dirisu and Matt Smith. The film tells the story of a refugee couple from South Sudan, ...
on land he leased in what is today Eastview, where his house still stands. Along the river to the north, his brother Staats Hammond built two mills along the river; the small settlement of Hammond's Mill became today's
Hawthorne Hawthorne often refers to the American writer Nathaniel Hawthorne. Hawthorne may also refer to: Places Australia *Hawthorne, Queensland, a suburb of Brisbane Canada * Hawthorne Village, Ontario, a suburb of Milton, Ontario United States * Hawt ...
. Other settlers came to the Saw Mill River's headwaters from a different direction.
Quaker Quakers are people who belong to a historically Protestant Christian set of Christian denomination, denominations known formally as the Religious Society of Friends. Members of these movements ("theFriends") are generally united by a belie ...
s had been immigrating to
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since the previous century to escape religious persecution in England; in the 1700s, "Shapequaw", north of the present hamlet of Chappaqua, was established. In the middle of the century, the community built its
meeting house A meeting house (meetinghouse, meeting-house) is a building where religious and sometimes public meetings take place. Terminology Nonconformist Protestant denominations distinguish between a * church, which is a body of people who believe in Chr ...
; it and other buildings of the era are today part of the Old Chappaqua
Historic District A historic district or heritage district is a section of a city which contains older buildings considered valuable for historical or architectural reasons. In some countries or jurisdictions, historic districts receive legal protection from c ...
, listed on the National Register of Historic Places in 1974.


Revolutionary War

As tensions rose between the colonists and Britain in the early 1770s, Philipse remained loyal to the crown. He was arrested in August 1776 and held in Connecticut until a parole grant at the end of the year allowed him to return home as long as he did nothing to support the British war effort. He broke that promise the next spring: he attempted, perhaps at the behest of his wife, to inform the British that a passing column of
Continental Army The Continental Army was the army of the United Colonies (the Thirteen Colonies) in the Revolutionary-era United States. It was formed by the Second Continental Congress after the outbreak of the American Revolutionary War, and was establis ...
troops was headed south to attack a British camp at Morrisania, now in the Bronx. Shortly afterwards he fled to British-occupied New York; he would never return to his home along the Saw Mill. Communities along the Saw Mill played minor parts in the Revolutionary War, especially after the Battle of White Plains in October 1776. The defeated Continentals retreated to the vicinity of Peekskill while the victorious British withdrew to Kingsbridge in what is now the Bronx. Neither side wanted to cede control of the Hudson Valley, which divided New England from the other colonies. This left most of Westchester unoccupied neutral ground. However, Westchester was not
demilitarized A demilitarized zone (DMZ or DZ) is an area in which treaties or agreements between nations, military powers or contending groups forbid military installations, activities, or personnel. A DZ often lies along an established frontier or bounda ...
. Local militias and raiding parties affiliated with both sides fought each other and terrorized the other's sympathizers and supporters. Many residents of southern Westchester abandoned their farms and drove their herds up the valley to Buttermilk Hill to protect them from Loyalist raids. The Continentals built forts near Hawthorne, where a minor tributary named Flykill Creek drained into the Saw Mill (roughly at the junction of today's Saw Mill and Taconic parkways), and built Yankee Dam to create a lake wide enough to slow any British progress up the river. At Chappaqua, the pacifist Quakers opened their meetinghouse as a hospital for injured
Continental Army The Continental Army was the army of the United Colonies (the Thirteen Colonies) in the Revolutionary-era United States. It was formed by the Second Continental Congress after the outbreak of the American Revolutionary War, and was establis ...
soldiers. Storm's tavern was a gathering place for Continental officers and, later, their French colleagues. As one of the few routes into hilly central Westchester, the river and its associated roads saw frequent skirmishes. In November 1777, three young men with Patriot sympathies were walking near the river crossing on the Dobbs Ferry Road (now Ashford Avenue) when they came upon a group of horsemen affiliated with Kipp's Regiment, one of the county's most-feared
Loyalist Loyalism, in the United Kingdom, its overseas territories and its former colonies, refers to the allegiance to the British crown or the United Kingdom. In North America, the most common usage of the term refers to loyalty to the British Cro ...
militias. The young men taunted their rivals, who beat them so severely that two later died. The survivor was awarded a
pension A pension (, from Latin ''pensiō'', "payment") is a fund into which a sum of money is added during an employee's employment years and from which payments are drawn to support the person's retirement from work in the form of periodic payments ...
, believed to be the first in U.S. history, by the
Continental Congress The Continental Congress was a series of legislative bodies, with some executive function, for thirteen of Britain's colonies in North America, and the newly declared United States just before, during, and after the American Revolutionary War. ...
. Later that month, Emmerich's Chasseurs, an elite unit of Loyalist militia and
Hessian A Hessian is an inhabitant of the German state of Hesse. Hessian may also refer to: Named from the toponym *Hessian (soldier), eighteenth-century German regiments in service with the British Empire **Hessian (boot), a style of boot **Hessian f ...
mercenaries, staged a midnight raid on Storm's Bridge. Hoping to capture Storm and his cousins the Van Tassels, all active in the local Patriot militia, the Chasseurs settled for burning and looting Storm's house and tavern. Proceeding on to the Van Tassel houses, they trapped Cornelius Van Tassel Jr., one of the cousins' teenage sons. As the Chasseurs set fire to the houses, he hid on a roof, then jumped off, fended off some putative captors, and fled into the cold waters of the nearby Saw Mill. He got away, but soon died of hypothermia. The Saw Mill River and its adjacent terrain conferred some tactical advantages to those who knew it. One skirmish began when a Patriot militiaman, Jake Acker, was hunting in a bushy area of the eastern flood plain at Elmsford. Spying a large group of British soldiers and Loyalist supporters on the road to Storm's tavern, Acker began sniping at them from his concealment. He fatally wounded one, changed his position amid the distraction, reloaded his musket, and killed another. Hearing the shots, other local Patriots came to Acker's aid, and eventually all but one of the larger force were killed or captured. Some senior Continental Army officers spent time in the Saw Mill River valley.
George Washington George Washington (February 22, 1732, 1799) was an American military officer, statesman, and Founding Father who served as the first president of the United States from 1789 to 1797. Appointed by the Continental Congress as commander of th ...
is said to have mentioned the " ford over the Nepperhan at the elm tree", referring to a wide tree no longer extant; a century later, residents named their hamlet after the remark, "Elmsford". He left a meeting at the Hammond House in Eastview moments before Loyalists converged on it; his host, Col. James Hammond, the commander of the Westchester militia, was captured and imprisoned for the rest of the war. On the British side, Major
John André John André (2 May 1750/1751''Gravesite–Memorial''
Westmi ...
spent his last night before his capture, with documents exposing
Benedict Arnold Benedict Arnold ( Brandt (1994), p. 4June 14, 1801) was an American military officer who served during the Revolutionary War. He fought with distinction for the American Continental Army and rose to the rank of major general before defect ...
's betrayal, at the Rookery inn in Hawthorne. Later in the war, Young's farmhouse and Four Corners were the site of the largest military engagement near the river. By 1780, the Continentals were operating much more freely around northern Westchester, although they had to stay on the move to avoid attack. In January, one
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of about 250 troops from Massachusetts lingered long enough at Four Corners for local Loyalists to inform the British, who raised a force of about 100 cavalry and 400 to 500 infantry at Fort Washington, today on the northern tip of Manhattan. The force marched to Yonkers and up the Saw Mill overnight, arriving at Four Corners the next morning. The outnumbered Continentals put up stiff resistance, aided by the cold, heavy snow cover and their opponents' fatigue, but most were ultimately killed or taken prisoner. The British and their Loyalist and Hessian allies celebrated by burning down the Young house; the Continentals retreated to the north of the Croton River for the rest of the war. In 1779, the New York State Legislature passed a bill of attainder confiscating the property of British officials and prominent Loyalists, Philipse included. The land, including land in the Saw Mill River watershed, was then distributed to the tenant farmers. In 1788, the state divided into three the town of
Greenburgh Greenburgh is a town in western Westchester County, New York. The population was 95,397 at the time of the 2020 census. History Greenburgh developed along the Hudson River, long the main transportation route. It was settled by northern Europeans ...
, in which the entire eastern half of the tract had been located. The towns of Yonkers and Mount Pleasant joined Greenburgh, all approximately within their present boundaries. In 1790, a group of settlers organized the Greenburgh Presbyterian Church, and three years later built a church at Storm's Bridge. (Today, it is the National Register-listed Elmsford Reformed Church, the oldest building in the village, the oldest church in continuous use in Westchester County.)


1800s and 1900s

Most of Yonkers' economy in the early 19th century was derived from the Saw Mill River. As of 1813, there was a small wharf slightly upstream from the mouth where the
sloop A sloop is a sailboat with a single mast typically having only one headsail in front of the mast and one mainsail aft of (behind) the mast. Such an arrangement is called a fore-and-aft rig, and can be rigged as a Bermuda rig with triangular sa ...
s that carried river trade put in. Five small mills existed along the river above the village, all with their own dams, small mill ponds, and nearby tenements for the workers. The stagecoach route up the Post Road stopped at an inn near the bridge; a few stores existed to supply the workers there and at the mills. Some pastures and orchards existed, but the rocky soil deterred most attempts at farming. (A historian later wrote that it was said at the time that "the succession of boulders was so continuous that one might have stepped from
Getty Square Getty Square is the name for downtown Yonkers, New York, centered on the public square. Getty Square is the civic center, central business district, and transit hub of the City of Yonkers. A dense and growing residential area, it is located ...
to the present Glenwood without setting his foot upon the ground".) Between the rocky soil and Wells' general refusal to sell or lease most of his land, there were so few settlers in Yonkers that two schoolhouses built during the Revolution fell into severe neglect due to the lack of students. The manor house and the surrounding land at the river's mouth that is today downtown passed through several owners until 1813, when New York merchant Lemuel Wells bought the around the manor house. Wells neither subdivided nor developed the property, although he did extensively landscape the manor house grounds. In 1831, Wells built a long wharf into the Hudson just above the mouth of the Saw Mill for the steamboat service which had been established between New York and Albany. Otherwise, the property remained largely unchanged until his death in 1842. Maps of the property from the time of Wells' purchase and his death show the Saw Mill's mouth widening into a small estuary before reaching the Hudson. The south bank of the river at the mouth had a bluff. The only construction directly affecting the river was the bridge that carried the Albany Post Road, today Riverdale and Warburton avenues, part of
U.S. Route 9 U.S. Route 9 (US 9) is a north–south United States highway in the states of Delaware, New Jersey, and New York in the Northeastern United States. It is one of only two U.S. Highways with a ferry connection (the Cape May–Lewes Ferry, between ...
and Route 9A, over the river. Wells had survived the death of his first wife and all four of his brothers; he also had no children, leaving him without a clear heir. His estate was further complicated by his lack of a will. Accordingly, under New York law at the time, his holdings were divided among his widow, fifteen nephews and one grand nephew. They decided to subdivide and sell the property, and within a few years more buildings had gone up, just in time for the construction of the
Hudson River Railroad The New York Central Railroad was a railroad primarily operating in the Great Lakes and Mid-Atlantic regions of the United States. The railroad primarily connected greater New York and Boston in the east with Chicago and St. Louis in the Mid ...
in 1848, which laid its track on a
causeway A causeway is a track, road or railway on the upper point of an embankment across "a low, or wet place, or piece of water". It can be constructed of earth, masonry, wood, or concrete. One of the earliest known wooden causeways is the Sweet Tra ...
right across the river's mouth. Over the next several decades, as Yonkers' population grew rapidly, leading it to incorporate as a village and then, in 1872, a city, the rest of the estuary was filled in and narrowed and the bluffs on its south side graded out of existence. By the later decades of the 19th century, industry had grown up along the river's lower portion. So much pollution was dumped into the river from the factories alongside it that a local poet lamented the Saw Mill's decline in an 1891
quatrain A quatrain is a type of stanza, or a complete poem, consisting of four lines. Existing in a variety of forms, the quatrain appears in poems from the poetic traditions of various ancient civilizations including Persia, Ancient India, Ancient Greec ...
: To let the river replenish itself, most of the dams that had been built were removed in 1893. Ten years later it had somewhat recovered, and people were again using it for drinking water and swimming. In the late 19th century, the
New York and Putnam Railroad The New York and Putnam Railroad, nicknamed the Old Put, was a railroad line that operated between the Bronx and Brewster in New York State. It was in close proximity to the Hudson River Railroad and New York and Harlem Railroad. All three cam ...
was built along the Saw Mill River from Putnam County to central Yonkers, and thence to Tibbets Creek and the Harlem River. Various parts of the line operated until the 1940s and the 1980s. The main line of the railroad is now devoted to bicycle and pedestrian paths. They are the
South County Trailway The South County Trailway is a long rail trail stretching from the Putnam Trail in Van Cortlandt Park in the Bronx to the North County Trailway in East View, New York. Westchester County Parks constructed the trailway in segments beginning in 1 ...
on the parts south of Route 119, and the
North County Trailway The North County Trailway is a long paved rail trail stretching from Eastview to Baldwin Place in Westchester County, New York. It is also part of the statewide Empire State Trail. History and route The North County Trailway was constructed ...
north of 119 in Elmsford. To slake the thirst of its ever-growing population, which had reached almost 100,000 by 1915, Yonkers tapped the Saw Mill. Water from an impoundment north of downtown was held in two reservoirs and two water towers. It was purified by slow
filtration Filtration is a physical separation process that separates solid matter and fluid from a mixture using a ''filter medium'' that has a complex structure through which only the fluid can pass. Solid particles that cannot pass through the filter ...
through sand and then chlorinated. By 1919 the city was drawing an average of 10.6 million gallons () a day from the river through this system. Despite this, the pollution of the river continued unabated, reversing its earlier recovery. In a 1920 report on the condition of public water supplies around the state, New York's
Health Department A health department or health ministry is a part of government which focuses on issues related to the general health of the citizenry. Subnational entities, such as states, counties and cities, often also operate a health department of their ow ...
said "sanitary conditions upon the Saw Mill watershed are very unsatisfactory", despite the considerable rules and regulations it had promulgated to protect the river in Yonkers. The city's own public works department had noted dozens of violations for the previous year, most of them continued from the years before that. "A great many privies and
cesspools A cesspit (or cesspool or soak pit in some contexts) is a term with various meanings: it is used to describe either an underground holding tank (sealed at the bottom) or a soak pit (not sealed at the bottom). It can be used for the temporary co ...
are located on the edge of the Saw Mill and its tributaries and there is also drainage from poultry yards, barnyards and house drains," the department noted Rather than enforce the violated regulations more strictly and clean up the river, the city chose to cover it up entirely. Between 1917 and 1922, the last of river, including a small
gorge A canyon (from ; archaic British English spelling: ''cañon''), or gorge, is a deep cleft between escarpments or cliffs resulting from weathering and the erosion, erosive activity of a river over geologic time scales. Rivers have a natural tenden ...
, was buried in a
culvert A culvert is a structure that channels water past an obstacle or to a subterranean waterway. Typically embedded so as to be surrounded by soil, a culvert may be made from a pipe, reinforced concrete or other material. In the United Kingdom ...
under the
Getty Square Getty Square is the name for downtown Yonkers, New York, centered on the public square. Getty Square is the civic center, central business district, and transit hub of the City of Yonkers. A dense and growing residential area, it is located ...
neighborhood, an effort to halt the river's frequent floods and quarantine its unsanitary water, and open up some space for further development. That same decade, the county parks commission proposed the
Saw Mill River Parkway The Saw Mill River Parkway (also known as the Saw Mill Parkway or the Saw Mill) is a north–south parkway that extends for through Westchester County, New York, in the United States. It begins at the border between Westchester County and the Bro ...
along the river, just as the 1922
Bronx River Parkway The Bronx River Parkway (sometimes abbreviated as the Bronx Parkway) is a long parkway in downstate New York in the United States. It is named for the nearby Bronx River, which it parallels. The southern terminus of the parkway is at Story Avenue ...
follows the Bronx River, and to add a sewer line along the river to prevent contamination of Yonkers' water supply. Construction began in 1929 and continued throughout the
Great Depression The Great Depression (19291939) was an economic shock that impacted most countries across the world. It was a period of economic depression that became evident after a major fall in stock prices in the United States. The economic contagio ...
. By 1940, the parkway had reached the river's headwaters at Chappaqua, where World War II temporarily halted construction. In 1954, it was complete. The parkway's construction, along with that of the
New York State Thruway {{Infobox road , state = NY , type = NYST , alternate_name = Governor Thomas E. Dewey Thruway , maint = NYSTA , map = {{maplink, frame=yes, plain=yes, frame-align=center, frame-width=290, type=line, stroke-width=2, type2=line, from2=New Yor ...
later in the decade, required some adjustment of the river's course in some areas. Westchester's postwar development led to more stormwater runoff, which often flooded and closed the parkway. By 1958, engineers were urging that the river be cleaned up to reduce flooding. Still, illegal dumping and overflows continued. For example, storm runoff gave the Yonkers section the river's highest concentrations of heavy metals, PCBs, and other chemicals, according to a study of the river in 1983, the year the city stopped using the Saw Mill as its primary water source. A decade later, the sediment in the Saw Mill had the highest concentration of metals in the United States Geological Survey's entire water-quality assessment program.


2000s

A new kind of pollution entered the lower Saw Mill in 2003 when a Yonkers sugar refinery spilled hydrochloric acid into the river. Westchester
District Attorney In the United States, a district attorney (DA), county attorney, state's attorney, prosecuting attorney, commonwealth's attorney, or state attorney is the chief prosecutor and/or chief law enforcement officer representing a U.S. state in a l ...
Jeanine Pirro brought criminal environmental charges against
American Sugar Refining American Sugar Refining, Inc. is a large privately held cane sugar refining company, with a production capacity of 6.5 million tons of sugar. The company produces a full line of consumer, industrial, food service, and specialty sweetener product ...
, the plant owner, which was forced to pay a $20,000 fine; make a $100,000 donation to
Riverkeeper Riverkeeper is a non-profit environmental organization dedicated to the protection of the Hudson River and its tributaries, as well as the watersheds that provide New York City with its drinking water. It started out as the Hudson River Fisherman' ...
, a regional environmental organization that focuses on the Hudson and its tributaries; and give of sugar to Westchester Food-PATCH, a local nonprofit that supplies food to other nonprofits. Riverkeeper passed the money it received along to the Saw Mill River Coalition for local projects in Yonkers. In 2008, Groundwork Hudson Valley, the coordinator of the Saw Mill River Coalition, received a three-year, $889,183 U.S. Environmental Protection Agency Targeted Watershed Grant. One of 15 recipients from a nationwide pool of more than 100 applicants, the group cleans up garbage, removes invasive species, and plants native trees along the river. The group also marks storm drains that drain to the river. On September 25–26, 2009, the Saw Mill River Coalition organized a BioBlitz to catalog species of plant life, animal life, insects, fungi, and bacteria in the river and its watershed. The Coalition is also looking to restore the wetlands along the river in order to reduce flooding. Raising of the Saw Mill Parkway continues; in 2013, a stretch in Pleasantville was raised by three inches to reduce flooding from the river.


Daylighting

The city of Yonkers carried out a $48 million
daylighting Daylighting is the practice of placing windows, skylights, other openings, and Reflective surfaces (climate engineering), reflective surfaces so that sunlight (direct or indirect) can provide effective internal lighting. Particular attention is ...
project in the 2010s to remove the culvert that the river flows through under Yonkers and bring the river to the surface. The project uncovered the river for six blocks in Downtown Yonkers. The newly surfaced river is the centerpiece of an urban park in
Getty Square Getty Square is the name for downtown Yonkers, New York, centered on the public square. Getty Square is the civic center, central business district, and transit hub of the City of Yonkers. A dense and growing residential area, it is located ...
, Downtown Yonkers. The first phase of the project removed a parking lot that covered a two-block section of the river in the Getty Square neighborhood of downtown Yonkers. Ground was broken on December 15, 2010, and the work was completed in December 2011. Work on the second phase, to expose the river in the Mill Street Courtyard, began on March 19, 2014 and was completed by August 2016. The project stimulated real estate investment in the area.


Recreation

The river affords some of the few remaining open spaces in Westchester County. Near Ardsley and Dobbs Ferry and Irvington, the river passes through V. Everit Macy Park, popular for picnicking and fishing in Woodlands Lake.
Butternut Ridge Park Butternut may refer to: * Butternut (tree), ''Juglans cinerea'', a species of walnut tree commonly called a butternut tree * Butternut squash, ''Cucurbita moschata'', an edible winter squash * USS ''Butternut'' (YAG-60), a 1941 ship of the United ...
contains the
Tarrytown Lakes Tarrytown is a village in the town of Greenburgh in Westchester County, New York. It is located on the eastern bank of the Hudson River, approximately north of Midtown Manhattan in New York City, and is served by a stop on the Metro-North ...
reservoirs and a hiking trail. Two bicycle trails run along parts of the river: the
North County Trailway The North County Trailway is a long paved rail trail stretching from Eastview to Baldwin Place in Westchester County, New York. It is also part of the statewide Empire State Trail. History and route The North County Trailway was constructed ...
and the
South County Trailway The South County Trailway is a long rail trail stretching from the Putnam Trail in Van Cortlandt Park in the Bronx to the North County Trailway in East View, New York. Westchester County Parks constructed the trailway in segments beginning in 1 ...
, which run from Van Cortlandt Park in the Bronx to Putnam County. The Saw Mill was also known as the closest trout fishing river to New York City. In the early 2000s, it was stocked with a few hundred trout each year. The lower river specifically is a good trout river.


Hydrology

The USGS maintains a
stream gauge A stream gauge, streamgage or stream gauging station is a location used by hydrologists or environmental scientists to monitor and test terrestrial bodies of water. Hydrometric measurements of water level surface elevation ("stage") and/or volu ...
on the Saw Mill just above the river's mouth in Yonkers. Mean
discharge Discharge may refer to Expel or let go * Discharge, the act of firing a gun * Discharge, or termination of employment, the end of an employee's duration with an employer * Military discharge, the release of a member of the armed forces from serv ...
since 1944 has been per second, with extremes of during the April 2007 nor'easter and . Average annual precipitation in the watershed is . The Saw Mill River's water quality varies, reflecting its history and surroundings. Its headwaters in the town of New Castle are considered "relatively healthy". There the river is less disturbed, and its ecosystem supports a diversity of organisms. In Yonkers, where it flows through a concrete-lined channel, there is less life in the water and it is considered to be environmentally impaired. A 1983 United States Geological Survey (USGS) study found that concentrations of
heavy metals upright=1.2, Crystals of osmium, a heavy metal nearly twice as dense as lead">lead.html" ;"title="osmium, a heavy metal nearly twice as dense as lead">osmium, a heavy metal nearly twice as dense as lead Heavy metals are generally defined as ...
in the water increased further downstream, a phenomenon observed with many other pollutants in the river and correlated with the urbanization around and above its mouth. DDT was detected in the streambed sediments throughout the river. In its final , more than 50 micrograms of PCBs were found per kilogram of water. In the 1990s, the USGS found that of the 35 Hudson tributaries it tested, the Saw Mill had the worst levels of cadmium, copper,
mercury Mercury commonly refers to: * Mercury (planet), the nearest planet to the Sun * Mercury (element), a metallic chemical element with the symbol Hg * Mercury (mythology), a Roman god Mercury or The Mercury may also refer to: Companies * Merc ...
, nickel and zinc in the sediments near its mouth, and among the worst nationwide (however, only the river's manganese levels were found to exceed federal standards). It is believed to add more pollution to the Hudson than any other single tributary. Unusually for a river, the Saw Mill's waters have consistently had a slightly
alkali In chemistry, an alkali (; from ar, القلوي, al-qaly, lit=ashes of the saltwort) is a basic, ionic salt of an alkali metal or an alkaline earth metal. An alkali can also be defined as a base that dissolves in water. A solution of a ...
ne pH, suggesting it has not been as affected by
acid rain Acid rain is rain or any other form of precipitation that is unusually acidic, meaning that it has elevated levels of hydrogen ions (low pH). Most water, including drinking water, has a neutral pH that exists between 6.5 and 8.5, but acid ...
as other Hudson tributaries. In 1951, a state Department of Health survey reported pH between 7.25 and 9.1. Four decades later, another study found pH readings rising steadily from 7.59 in Chappaqua to 8.24 in Yonkers. Similarly, a 2007
Manhattan College Manhattan College is a private, Catholic, liberal arts university in the Bronx, New York City. Originally established in 1853 by the Brothers of the Christian Schools (De La Salle Christian Brothers) as an academy for day students, it was la ...
study done for the New York State Water Resources Institute found a
median In statistics and probability theory, the median is the value separating the higher half from the lower half of a data sample, a population, or a probability distribution. For a data set, it may be thought of as "the middle" value. The basic fe ...
low of 7.36 in Chappaqua and a median high of 7.81 near Torre Road in Yonkers, with a drop to 7.67 at the tunnel, for a total median for the river of 7.59. The lowest recorded pH in the year-long study was 7.1 at Chappaqua with the highest reading, 8.17, at Torre Road. All results were between 6.5 and 8.5, the range required by state regulations. The 1983 USGS study also classified the water quality of the entire river. The first from the river's source in Chappaqua was classified as suitable for any purpose besides drinking. The next was classified as being safe to drink. The last of the river from the sewage treatment plant to the Hudson was determined to be unsafe to drink, bathe in or fish in. The water was only safe for agricultural and industrial use. In regulations adopted in 1985 and amended in 2008, New York's Department of Environmental Conservation (DEC) divides the river into four water-quality regions similar to those in the 1983 USGS study. The first from the Saw Mill's mouth is affected by the Hudson's tides and thus is often salty like the river at that point. It is considered Saline Class B
surface water Surface water is water located on top of land forming terrestrial (inland) waterbodies, and may also be referred to as ''blue water'', opposed to the seawater and waterbodies like the ocean. The vast majority of surface water is produced by prec ...
, to be kept suitable for primary and secondary contact recreation such as swimming, boating and fishing, and capable of supporting "fish, shellfish and wildlife propagation and survival." The next section extends to the tailwater at the Yonkers sewage plant impoundment, and is Class C fresh water, with the same purposes, to the extent that "other factors" do not limit them. From there to the Woodlands Lake inlet is the third section, designated as Class A fresh water, to be kept clean enough for drinking. The remainder to the source is the fourth section, designated Class B, or fresh water kept to the same standards as the salt water above the river's mouth. Tributaries, named and unnamed, and subtributaries are generally held to the same standards as the section into which they drain. A 1991 study by Irene Gruenfeld, a Williams College undergraduate, measured various pollutants at eight points along the river, from just below the duck pond in Chappaqua to inside the tunnel in Yonkers. The levels increased as the river flowed along, suggesting that most pollutants, especially dissolved salts, came from urban runoff instead of any single point source. The exception was PCBs, which rose drastically south of Elmsford (a finding that concurred with an earlier study) and then doubled in Yonkers. The study noted that this suggested a point source, perhaps a known burial site for used capacitors in the Elmsford area, yet Gruenfeld argued that cleaning up this and other possible point sources would not eliminate PCBs in the river. While the PCBs in the river were found somewhat biodegraded, chlordane levels are high enough that DEC recommends eating no more than a half-pound () of fish or eel from the Saw Mill per month. A 2004-05 EPA study of the river rated the water quality 6 out of 100. The study also discovered that dissolved oxygen levels in the water were low because there were few organisms, poor sediment, and little plant life in the river. Although storm water from residential neighborhoods added dissolved oxygen, it also brought ammonia from fertilizer. The Army Corps of Engineers found that the channeling prevented aquatic life from sustaining itself; few fish naturally spawn in the river because of the cement casing and culvert at its mouth. Two years later, a joint study by Manhattan College and the New York State Water Resources Institute found high levels of human fecal bacteria in the water, likely due to municipal wastewater. All 12 sites exceeded the state maximum of a monthly median of 200 organisms per 100 milliliters (ml) over five months. Levels were, as with most of the river's other pollutants, generally the highest near the mouth. However, the uppermost sampling site in the study, at the Chappaqua Metro-North station recorded the greatest single reading of any site, 1.2 × 10 organisms per 100 ml, as well as the second-highest; the researchers speculated that this was due to sewer overflow in the area at the times of those readings. Most of the high coliform readings came after rainfall except at the two sites furthest downstream; the study theorized that some older buildings in this area of Yonkers may still discharge sewage directly to the river. Since most of the Saw Mill River flows under the shade of a forest canopy, the bacteria may be less likely to be inactivated by sunlight than in other streams. The riverbanks in Yonkers are often lined with tires, shopping carts, plastic bottles, and other trash. In 2008, DEC found trash and pollution from the river's mouth to the end of the tunnel. "Urban refuse (tires, bottles, cans, etc.) lines much of the lower river," it reported. "Oil/gasoline slicks are regularly observed along this segment." The stretches further upriver were slightly better. Between the end of the tunnel and Woodlands Lake, the river was still found to be impaired for recreation, drinking and aquatic life, but less strewn with litter, and as a whole the habitat was merely stressed. Above that point, the Saw Mill's waters were merely stressed for aquatic life and recreation, with only fish consumption considered to be impaired. DEC did not know the sources of pollutants in this stretch and called for further research."


Geology

The Saw Mill's basin is part of the
Manhattan Hills In the United States, the Manhattan Prong of the New England Uplands is a smaller belt of ancient rock in southern New York (including Manhattan, the Bronx, and segments of Brooklyn and Staten Island), parts of Westchester County, and upland porti ...
in the New England Uplands physiographic region. It is primarily underlain by metamorphic rock such as gneiss, schist and marble. They can be seen in some
bedrock In geology, bedrock is solid Rock (geology), rock that lies under loose material (regolith) within the crust (geology), crust of Earth or another terrestrial planet. Definition Bedrock is the solid rock that underlies looser surface mater ...
outcrops in and around the river. Soils in the river and its basin reflect past glaciation in the area. Glacial till covers much of the river bottom in its headwaters. Further downstream there is stratified
drift Drift or Drifts may refer to: Geography * Drift or ford (crossing) of a river * Drift, Kentucky, unincorporated community in the United States * In Cornwall, England: ** Drift, Cornwall, village ** Drift Reservoir, associated with the village ...
and alluvium in the sediments.


Flora and fauna

The
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 America ...
lives in the Saw Mill River and its tributaries. Commonly born in the Atlantic Ocean, the eels maneuver through the river's tunnel under Yonkers before reaching the more natural parts of the river farther upstream. The eels also scale a dam before reaching Woodlands Lake. Growing up to in length upstream, the eels return to the ocean via the Hudson River to spawn. The planned installation of trash-catching nets along the daylighted portion of the river would prevent the eels from leaving the river to reproduce. More fish have been discovered in the newly daylighted section of the river. Baby eastern blacknose dace and
tessellated darter The tessellated darter (''Etheostoma olmstedi'') is a species of freshwater ray-finned fish, a darter from the subfamily Etheostomatinae, part of the family Percidae, which also contains the perches, ruffes and pikeperches. It is native to Canad ...
have been spotted in the river in addition to trout. In addition, wood frogs, eastern painted turtles, and redbreast sunfish live in the river too. All of these species have been hurt by the industrialization of the river. About 10 to 20 white-tailed deer per square mile (2.6 to 5.2 deer per square kilometer) live along the river and the parkway, more than the ecosystem can carry. They eat low-lying plants, shrubs, and tree saplings, reducing the food supply for smaller animals. The deer also collide with cars—in Hastings, about 1.6 times per month. Beavers can also be found along the river, building small dams along the river. Night herons, ducks, and other birds are also present along the river. Numerous invasive plants live along the Saw Mill River.
Porcelain berry ''Ampelopsis glandulosa'' is a species of plant native to China, Japan, India, Nepal, Myanmar, Vietnam, and the Philippines. Varieties Several varieties are distinguished: * var. ''hancei'' * var. ''kulingensis'' * var. ''glandulosa'' * var ...
is a vine with white berries that wraps around native trees and strangles them.
Oriental bittersweet ''Celastrus orbiculatus'' is a woody vine of the family Celastraceae. It is commonly called Oriental bittersweet, as well as Chinese bittersweet, Asian bittersweet, round-leaved bittersweet, and Asiatic bittersweet. It is native to China, wh ...
is also present along the river, and it is slowly displacing the native
American bittersweet ''Celastrus scandens'', commonly called American bittersweet or bittersweet, is a species of ''Celastrus'' that blooms mostly in June and is commonly found on rich, well-drained soils of woodlands. It is a sturdy perennial vine that may have tw ...
. Oriental bitterweet can also form hybrids with the native bittersweet and making identification harder. Japanese honeysuckle and Japanese knotweed are two other invasive vines native to Asia. In addition, purple loosestrife, a perennial herb with magenta flower stalks, is also present along the river. Native trees on the river include the pin oak and staghorn sumac. These trees were found along Woodlands Lake, but can be found throughout the entire Hudson Valley. Other native plants include evening primrose, an invasive species in Europe, and wild lettuce.


See also

*
List of rivers of New York This is a list of rivers in the U.S. state of New York. By drainage basin This list is arranged by drainage basin, with respective tributaries indented by order of confluence with their main stem, from mouth to source. Long Island Sound (nort ...


References


External links


Report on daylighting the Saw Mill River by the US Environmental Protection AgencyCourse of the river
on
OpenStreetMap OpenStreetMap (OSM) is a free, open geographic database updated and maintained by a community of volunteers via open collaboration. Contributors collect data from surveys, trace from aerial imagery and also import from other freely licensed g ...

Saw Mill River Coalition's history of the river Groundwork Hudson Valley
{{Good article Rivers of Westchester County, New York Tributaries of the Hudson River Subterranean rivers of the United States Rivers of New York (state)