Percent of Impaired Stream Miles
Current Value
8%
Definition
Story Behind the Curve
In 2018-2020, 8% of all stream miles are impaired. This indicator measures the lakes and ponds and the total number of stream/river miles that are either impaired, stressed, or altered with a pollutant that causes a violation of the Vermont Water Quality Standards and the Clean Water Act.
Impairment Level | Stream/shoreline miles | % of total | lake/pond |
2020 303d part a: A total maximum daily load (TMDL) is deemed necessary for these waters in order to establish the maximum limit of a pollutant that may be introduced into the water and still ensure the Water Quality Standards are attained and maintained. | 26.5 | 2% | Lake Champlain (including Burlington Bay, Shelburne Bay, Malletts Bay, Main lake) Shelburne Pond |
2018 Part b:Impaired and do not require development of a total maximum daily load (TMDL) because other pollution control requirements by local, state, or federal authority are stringent enough to implement any water quality standard (WQS) applicable to such waters. | 7.8 | 1% | Bulington Bay - Lake Champlain - Pine Street Barge Canal |
2018 Part c: In need of further study to confirm the presence of a violation of one or more criteria of the Vermont Water Quality Standards | 0 | 0% | none |
2018 Part d: Completed and approved TMDLs in place, though they are not meeting water quality standards | 93.2 | 6% | Burlington Bay, Shelburne Bay, Malletts Bay, Arrowhead Mountain Lake |
2018 Part E: Altered by invasive aquatic species | 0 | 0% | Lake Iroquois, Indian Brook Reservoir, Arrowhead Mountain Lake, Shelburne Pond, Lake Champlain (including Burlington Bay, Shelburne Bay, Mallets Bay) |
2018 Part F: Altered by flow regulation | 3.36 | 0% | none |
Total impaired miles of streams* | 110.2 | 8% | |
Total Stream miles | 1,453 |
Why Is This Important?
Water bodies continue to face mounting pressures from development, farm, and forest activities. Cumulative impacts from these land use activities have degraded water quality, aquatic habitat, and altered the stability of river corridors and lake shores. Issues that predominate in the County include steady high pollutant loads (mainly from non-point sources such as unmanaged storm water), that result in nutrient enrichment and sedimentation, as well as other impairments. In addition, aquatic nuisance species continue to enter our water ways, contributing to the degradation of both habitat and recreational opportunities.