Ambrose Brook is a tributary

Tributary

A tributary or affluent is a stream or river that flows into a main stem river or a lake. A tributary does not flow directly into a sea or ocean...

 of Green Brook in Middlesex County

Middlesex County, New Jersey

-Demographics:As of the census of 2000, there were 750,162 people, 265,815 households, and 190,855 families residing in the county. The population density was 2,422 people per square mile . There were 273,637 housing units at an average density of 884 per square mile...

, New Jersey

New Jersey

New Jersey is a state in the Northeastern and Middle Atlantic regions of the United States. , its population was 8,791,894. It is bordered on the north and east by the state of New York, on the southeast and south by the Atlantic Ocean, on the west by Pennsylvania and on the southwest by Delaware...

 in the United States

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

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It rises underneath Route 27

Route 27 (New Jersey)

Route 27 is a state highway in New Jersey, United States. It runs from U.S. Route 206 in Princeton Borough, Mercer County northeast to an interchange with Route 21 and Broad Street in Newark, Essex County. The route passes through many communities along the way, including New Brunswick, Metuchen,...

 in Edison

Edison, New Jersey

Edison Township is a township in Middlesex County, New Jersey. What is now Edison Township was originally incorporated as Raritan Township by an Act of the New Jersey Legislature on March 17, 1870, from portions of both Piscataway Township and Woodbridge Township...

. It then flows into Lake Papaianni. It continues flowing northwest, parallel to County Route 529

County Route 529 (New Jersey)

County Route 529 is a county highway in the U.S. state of New Jersey. The highway extends from Woodbridge Avenue in Edison to Mountain Boulevard in Watchung.-Route description:...

. After crossing Route 529 and Ethel Road West, it forms a border to some businesses in Piscataway

Piscataway Township, New Jersey

The township consists of the following historic villages and areas: New Market, known as Quibbletown in the 18th Century, Randolphville, Fieldville and North Stelton...

, including William Kenyon and Sons, Inc. Upon flowing into Lake Nelson, the brook takes a more westerly route into Ambrose Doty's Park. Doty's Brook flows into it near Behmer Road in Piscataway. It then flows through undeveloped land as it crosses Interstate 287

Interstate 287

Interstate 287 is an auxiliary Interstate Highway in the U.S. states of New Jersey and New York. It is a partial beltway around New York City, serving the northern half of New Jersey and the counties of Rockland and Westchester in New York...

 near Possumtown Road. It continues flowing west into the pond at Victor Crowell Park in Middlesex

Middlesex, New Jersey

Middlesex is a Borough in Middlesex County, New Jersey, United States. As of the 2010 United States Census, the borough population was 13,635.Middlesex was incorporated as a borough by an Act of the New Jersey Legislature on April 9, 1913, from portions of Piscataway Township, based on the results...

 The brook then takes a southwest turn and flows into the Green Brook near Lincoln Boulevard in Middlesex just before the Raritan River

Raritan River

The Raritan River is a major river of central New Jersey in the United States. Its watershed drains much of the mountainous area of the central part of the state, emptying into the Raritan Bay on the Atlantic Ocean.-Description:...

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