Lake Champlain Watershed
A brief overview of this watershed and its water quality is presented here. For more detailed information about the Lake Champlain 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
The Lake Champlain Watershed (8,234 square miles) drains the area between the Adirondack Mountains in northeastern New York State and the Green Mountains in northwestern Vermont. The long, narrow and deep lake has its outlet at its northern end where it flows through the Richelieu River into Quebec and empties into the Saint Lawrence River.
Location: Northeastern New York State
- Most of Clinton County,
- Much of Essex County,
- Southwest portion of Franklin County,
- Eastern portion of Warren County, and
- Northern portion of Washington County.
Size: 3,050 square miles of land area within New York State.
Rivers and Streams: 4,883 miles of freshwater rivers and streams. Major tributary watersheds to Lake Champlain in New York State include:
- Ausable River (767 river miles)
- Saranac River (662 miles)
- Great Chazy River (545 miles)
- Boquet River (532 miles)
- Mettawee River (390 miles)
- Ticonderoga Creek/Lake George (380 miles)
Lakes, Ponds and Reservoirs: Excluding Lake Champlain (278,480 acres), 235 significant freshwater lakes, ponds, and reservoirs (159,302 acres), including:
- Lake George (28,523 acres)
- Upper Saranac Lake (4,844 acres)
- Lower Saranac Lake (2,145 acres)
- Lake Placid (1,954 acres)
How is the Water?
Water Quality in The Lake Champlain Watershed
In the Lake Champlain Watershed, about 51% of river/stream miles, and 94% of lake, pond and reservoir acres have been assessed (see Assessment Report).

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.
Water quality in the Lake Champlain Watershed is generally good to excellent. Lake Champlain itself is the dominant feature of the watershed and the most significant water quality issues are associated with the lake. These include fish consumption advisories and phosphorus loadings, primarily from nonpoint sources throughout the watershed. Atmospheric deposition of acid rain and mercury also impact water quality and are of concern.
Major water quality concerns in the watershed are:
- Acid Rain which limits the fish community and aquatic life
- Atmospheric Deposition of Mercury which restricts fish consumption
- Agricultural and Other Nonpoint Sources of nutrients and various other pollutants
About Water Quality in New York State

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
Published Water Quality Monitoring and Assessment Reports
- Waterbody Inventory/Priority Waterbodies List - Assessment Report of overall water quality.
- Bioassessment Reports - Biological Surveys of specific rivers and streams.
- Groundwater Study Reports and Data
- Other Reports - Miscellaneous reports on the waters and water quality issues of the watershed.
Watershed Management Plans
- Halfway Brook Watershed Management Plan (offsite link)
- Lake George Watershed Management Plan (offsite link)
More about Lake Champlain Watershed:
- Lake Champlain Watershed Reports - DEC reports for the Lake Champlain Watershed
- Lake Champlain Watershed Map - Detailed map of the Lake Champlain Watershed