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Chemung River Watershed

A brief overview of this watershed and its water quality is presented below. For more detailed information about the Chemung 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 Allegheny Watershed
Click to view a detailed map of the watershed

The Chemung River Watershed (2,600 square miles) straddles the border between New York and Pennsylvania. The waters of the Chemung River flow across the western portion of Southern Tier of New York State before joining the Susquehanna River and eventually emptying into the Chesapeake Bay. The Chemung Watershed represents about one-eighth of the larger Susquehanna River Basin.

Location: Southern Tier of New York State

  • Most of Chemung and Steuben Counties,
  • Portion of southwestern Schuyler and western Allegany Counties, and
  • Small parts of Yates, Ontario and Livingston Counties.

Size: 1,740 square miles of land area within New York State.

Rivers and Streams: 4,086 miles of freshwater rivers and streams. Major tributary watersheds to the 41 miles of Chemung River in New York State include:

  • Cohocton River (1,099 river miles )
  • Tioga/Canisteo Rivers (979 miles)

Lakes, Ponds and Reservoirs: 23 significant freshwater lakes, ponds, and reservoirs (2,904 acres), including:

  • Lamoka Lake/Mill Pond (825 acres)
  • Waneta Lake (781 acres)
  • Almond Lake (480 acres)

How is the Water?

Water Quality in The Chemung River Watershed

Water quality Pie Chart. Rivers: 40% good, 32% Satisfactory, 2% Poor, 27% unassessed. Lakes: 0% good, 7% satisfactory, 76% poor, 17% 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 activities and uses
Unassessed: Insufficient data available

In the Chemung Watershed, about 73% of river/stream miles, and 83% of lake, pond and reservoir acres have been assessed (see Assessment Report).

Water quality in the New York portion of the Chemung River Watershed is generally satisfactory, although aquatic weed growth and invasive species cause impacts to some of the larger lakes in the watershed. Various nonpoint sources are the most frequently cited source of impacts in this mostly rural area.

Major water quality concerns in the watershed are:

  • Agricultural and Other Nonpoint Sources of nutrients and various other pollutants,
  • Flooding Impacts in the flood-prone Southern Tier,
  • Protection of Municipal Water Supply in the Elmira area.

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 Chemung River Watershed: