The pipe is a part of the old Ridgewood Water Supply system that ran though the area onto Conduit Boulevard. A vast portion of Valley Streams ponds and creeks fed Brooklyn with drinking water through the early part of the last century.
Here's what former NYC Mayor Bloomberg said about the old system:
"In 1862, the water supply for the reservoir consisted of six dammed streams in what is now Queens and Nassau Counties: Jamaica Stream (Baisley Pond), Simonson’s Stream, Clear Stream, Valley Stream, Pine’s Stream, and Hempstead Stream (Hempstead Lake). This water was carried in a 12-mile-long masonry conduit, called the Ridgewood Aqueduct, to a pumping station at Atlantic Avenue and Chestnut Street near the City Line. There, steam-powered pumps, each with a capacity of 14 million gallons per day, forced the water up through a reinforced tube into the high reservoir whence it was distributed. By 1868 the Ridgewood Reservoir held an average of 154.4 million gallons daily, enough to supply the City of Brooklyn for ten days at that time."
And here's a map:
http://www.vsvny.org/vertical/Sites/%7B ... System.pdf
Here's what former NYC Mayor Bloomberg said about the old system:
"In 1862, the water supply for the reservoir consisted of six dammed streams in what is now Queens and Nassau Counties: Jamaica Stream (Baisley Pond), Simonson’s Stream, Clear Stream, Valley Stream, Pine’s Stream, and Hempstead Stream (Hempstead Lake). This water was carried in a 12-mile-long masonry conduit, called the Ridgewood Aqueduct, to a pumping station at Atlantic Avenue and Chestnut Street near the City Line. There, steam-powered pumps, each with a capacity of 14 million gallons per day, forced the water up through a reinforced tube into the high reservoir whence it was distributed. By 1868 the Ridgewood Reservoir held an average of 154.4 million gallons daily, enough to supply the City of Brooklyn for ten days at that time."
And here's a map:
http://www.vsvny.org/vertical/Sites/%7B ... System.pdf