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Ramapo River Watershed

A brief overview of this watershed and its water quality is presented below. For more detailed information about the Ramapo River Watershed, published NYSDEC reports are also available. General information about watersheds is available at the "We All Live in a Watershed" webpage.

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 watersheds 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 include:

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

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

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

How is the Water?

Water Quality in The Ramapo River Watershed

Water quality Pie Chart. Rivers: 6% good, 38% Satisfactory, 22% Poor, 34% unassessed. Lakes: 6% good, 28% satisfactory, 24% poor, 42% unassessed
Good water quality: Fully supports designated activities and uses.
Satisfactory: Fully supports designated activities, but with minor impacts.
Poor (Impaired): does not support designated activites and uses.
Unassessed: Insufficient data available.

In the Ramapo Watershed, about 66% of river/stream miles, and 58% of lake, pond and reservoir acres have been assessed (see Assessment Report).

Water quality in the Ramapo River Watershed is affected by the extensive urbanization and suburban/commercial development of the area. Urban/stormwater runoff is the primary source of water quality impacts in the watershed. Municipal wastewater discharges also contribute to impacts; not surprising given the density of population in the area.

Major water quality concerns in the watershed are:

  • Urbanization and Suburban/Commercial Development that increases stormwater runoff
  • Municipal and Residential Wastewater Discharges in the heavily populated area
  • Protection of Groundwater and Surface Water Supplies.

About Water Quality in New York State

Water chemistry sampling in a NYS stream
Water Chemistry Sampling

Each waterbody in NYS has been assigned a classification, which reflects the designated "best uses" of the waterbody. These best uses typically include the ability to support fish and aquatic wildlife, recreational uses (fishing, boating) and, for some waters, public bathing, drinking water use or shellfishing. Water quality is considered to be good if the waters support their best uses. NYSDEC routinely monitors and assesses water quality throughout the state and publishes detailed reports of these findings. For more information on these monitoring and assessment programs, see Water Quality Monitoring, Assessment and Planning.

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.

<Biological kick sampling in a NYS stream
Biological Kick Sampling

Published Water Quality Monitoring and Assessment Reports

More about Ramapo River Watershed: