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Oswego River/Finger Lakes Watershed

Published Water Quality Monitoring and Assessment Reports

Waterbody Inventory/Priority Waterbodies List Report

Biological Assessment Reports

Other Reports

Watershed Management Plans

Links leave DEC website:

Facts about this Watershed

Map of NYS identifying the Oswego River/ Finger Lakes Watershed
Click to view a detailed map of the watershed

The Oswego River/Finger Lakes Watershed is one of the largest in New York State and includes the drainages of the Oswego, Oneida, Seneca and Clyde Rivers. Its headwaters originate in the southwestern Adirondack Mountains in the east and along the northern edge of the Appalachian Plateau and flow across the central lowlands before emptying into Lake Ontario. The watershed includes most of the New York Finger Lakes; in fact, lakes make up about 6% of the total surface area of the watershed.

Location: Central New York State

  • All of Seneca County,
  • Most of Onondaga, Cayuga, Tompkins, Schuyler, Yates and Ontario Counties,
  • Much of Oswego, Oneida, Madison and Wayne Counties, and
  • Smaller parts of Lewis, Cortland, Chemung, Steuben and Livingston Counties.

Size: 5,070 square miles of land area entirely within New York State.

Rivers and Streams: 8,896 miles of freshwater rivers and streams. Major tributary watersheds to the Oswego River and Finger Lakes:

  • Oneida River (2,330 river miles)
  • Clyde River (1,630 miles)
  • Cayuga Lake Tributaries (1,500 miles)
  • Seneca Lake Tributaries (1,240 miles)

Lakes, Ponds and Reservoirs: 76 significant freshwater lakes, ponds, and reservoirs (189,722 acres):

  • Oneida Lake (51,091 acres)
  • Cayuga Lake (42,812 acres)
  • Seneca Lake (42,646 acres)
  • Keuka Lake (11,712 acres)
  • Canandaigua Lake (10,605 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.

Fishing In The Finger Lakes


More about Oswego River/Finger Lakes Watershed: