Bog Brook Reservoir

The Bog Brook Reservoir is a 379-acre (153 ha) reservoir in the Croton Watershed in southern New York State. It is located in the town of Southeast, New York in Putnam County, and is approximately 38 miles (over 60 kilometres) north of New York City, to which it supplies water. It was formed by the damming of Bog Brook, a small tributary of the East Branch of the Croton River, which is in turn a tributary of the Croton River. This reservoir was put into service in 1892, making it one of the older reservoirs in New York City's water supply system.

The resulting body of water holds 4.4 billion US gallons (17,000,000 m3) of water at full capacity, and has a drainage basin of 4 square miles (6.4 square km). The drainage basin is an area of land surrounding a reservoir which has creeks, lakes, and other sources of water that supply their water to said reservoir. If one of those creeks is impounded to form a reservoir, that makes another drainage basin.

The Bog Brook is one of 12 reservoirs in New York City's Croton Water Supply System. Its main function is to serve as a storage reservoir for the larger East Branch Reservoir. The Bog Brook is connected to the nearby East Branch Reservoir by an underground tunnel.

From the East Branch Reservoir, the water flows into the continuation of the East Branch of the Croton River, then into The Diverting Reservoir, then via the Croton River to the Muscoot Reservoir and the New Croton Reservoir, into the New Croton Aqueduct, and finally to the Jerome Park Reservoir in the Bronx for distribution to New York City. It will then flow through Manhattan, and mix with the water from the Catskill Aqueduct.