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Ramapo River Watershed

Published Water Quality Monitoring and Assessment Reports

Biological Assessment Reports

Facts about this Watershed

Map of NYS identifying the Ramapo River Watershed
Click to view a detailed map of this watershed

The Ramapo River Watershed is part of the Passaic River Basin (925 square miles) which is located primarily in northern New Jersey. However the northern headwaters of the basin lie within a small portion of southeastern New York State. Within New York State, this watershed is drained primarily by the Ramapo and Hackensack Rivers. It is the smallest watershed in New York State.

Location: Southeastern New York State

  • Much of Rockland County, and
  • Portion of southern Orange County.

Size: 211 square miles of land area within New York State.

Rivers and Streams: 320 miles of freshwater rivers and streams. Major tributary watersheds to this drainage area within New York State:

  • Ramapo River (155 river miles)
  • Hackensack River (74 miles)

Lakes, Ponds and Reservoirs: 35 significant freshwater lakes, ponds, and reservoirs (5,162 acres):

  • Greenwood Lake (1,075 acres within New York State)
  • DeForest Lake (720 acres)

What You Can Do

Each of us lives in a watershed. On our Watershed Stewardship page are some tips on actions that you and your friends can take to help your watershed.

More about Ramapo River Watershed: