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Lake Champlain Watershed Program

The Lake Champlain Watershed 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, which spans 120 miles with a maximum depth of 400 feet, has its outlet at its northern end where it flows through the Richelieu River into Quebec and empties into the Saint Lawrence River.

Watershed Facts:

  • Area: 8,234 square miles
  • New York Area: 3,050 square miles
  • Population: 571,000
  • New York Population: 154,000
  • Lake Area: 278,480 acres

New York's Connection to Lake Champlain

New York's portion of the Lake Champlain watershed is made up 4,883 miles of freshwater rivers and streams. Major tributary watersheds to Lake Champlain in New York State include the Ausable River (767 river miles), Saranac River (662 miles), Boquet River (532 miles), Mettawee River (390 miles) and Ticonderoga Creek/Lake George (380 miles)

There are 235 significant freshwater lakes, ponds, and reservoirs (covering 159,302 acres total) within the watershed, including Lake George (28,523 acres), Upper Saranac Lake (4,844 acres), Lower Saranac Lake (2,145 acres), and Lake Placid (1,954 acres).

In total, some of five New York counties are in the Lake Champlain watershed: Clinton, Essex, Franklin, Warren and Washington.

Water Quality Problems and Solutions

Excess nutrients (phosphorus) and sediment from all over the Lake Champlain watershed degrade the Bay's water quality. Nutrient sources include sewage, manure, inorganic fertilizer, urban stormwater and sediment-bound phosphorus from eroded streambanks, fields, and rural roads.

Lake Champlain Phosphorus Total Maximum Daily Load

In 2002 the US Environmental Protection Agency (USEPA) approved the Lake Champlain Phosphorus Total Maximum Daily Load (TMDL) (leaves DEC website) developed jointly by Vermont and New York. The Lake Champlain TMDL outlines the maximum amount of phosphorous pollution that the lake can receive and still meet water quality standards.
The TMDL established the necessary reductions in phosphorous for each wastewater treatment facility (WWTF) in Vermont and New York as well as reductions needed from agricultural, developed, and forested land in each sub-watershed of the Lake. There has been significant effort to address phosphorous sources in the New York portion of the Lake Champlain watershed, phosphorous levels in most areas of the lake continue to exceed TMDL target concentrations.

Lake Champlain Harmful Algal Bloom Action Plan

Harmful algal blooms (HABs) have been of concern over the past few years due to increased frequency and duration in blooms that have resulted in frequent bathing beach closures near Port Henry and Isle LaMotte. NYSDEC, along with the New York State Department of Health (NYSDOH) and New York State Department of Agriculture and Markets (NYSDAM), developed a Harmful Algal Bloom Action Plan for Lake Champlain in 2018 to identify conditions that contribute to the formation of HABs and determine immediate and long-term actions to reduce their frequency.

Lake Champlain Draft Watershed Implementation Plan

The Lake Champlain Draft Watershed Implementation Plan was written as a companion document to the 2002 Lake Champlain TMDL. The plan uses land use analyses to estimate nutrient load from each subwatershed in the basin and provides estimates of the geographic sources of phosphorus pollution by each source sector or type (Agriculture, Developed, Forested, Septic and Wastewater). 

The document uses these estimates along with partner input to create implementation strategies and align potential funding sources for implementation by each source sector. Each source sector chapter presents a list of subwatersheds, ranked in priority order based on phosphorus loading and recommended best management practices. This targeting strategy will allow DEC and its partners to achieve the largest amount of phosphorus reduction where it is most needed with the lowest cost over time. 

Important Links:

Lake Champlain Water Quality and Assessment Reports

Lake Champlain Basin Program (leaves DEC website)

Champlain Watershed Improvement Coalition of New York (CWICNY) (leaves DEC website)

Lake George - Lake Champlain Regional Planning Board (leaves DEC website)