Deerfield River and Lower Connecticut River

Lake monitoring shows generally good conditions although all are impacted by the atmospheric deposition of acid rain and mercury. One, Sadawga Lake (#7), is known to have invasive Eurasian watermilfoil.

The water quality in Lake Raponda (#20) meets Vermont's criteria for Class A(1).

are recommended for reclassification, for special designation or for further study. These waters meet or exceed water quality criteria for the recommended class or will be studied to verify they meet criteria. Working with partners, the public and the legislature, waters can be petitioned for higher levels of protection in order to ensure the high quality water and the public uses these waters support are not degraded in the future.

Candidate waters for reclassification proposed in the Plan include:

Waters of concern are  listed  as 303(d) Impaired or Altered. Beyond acid and mercury the causes of the water quality problems include bacteria, nutrients or another pollutant, sediment, temperature or flow alterations.

These waters will be the focus for restoration to improve water quality and habitat conditions.

The Connecticut River flows into Long Island Sound (LIS) and is under an  EPA Total Maximum Daily Load  (TMDL) for low dissolved oxygen levels in the Sound. Low DO, known as hypoxia, is caused by excess nitrogen entering rivers and streams. Basin 12 is responsible for approximately 10.2% of Vermont’s nitrogen load. 

This map, from the  Long Island Sound Study , illustrates the areas of Long Island Sound that are most frequently affected by hypoxia.  The colors on the map show the improvement of the hypoxic conditions between 1993 and 2023. The Long Island Sound Water Quality Monitoring program was instituted in the early 1990s.

Modeling of nitrogen entering the Connecticut River from Basin 12 shows that the majority comes from atmospheric deposition. Urban land runoff, septic systems, agriculture and wastewater facilities make up the remainder of the nitrogen exported.

This chart, based on modeling data, estimates that Basin 12 is contributing more nitrogen from both urban land and residential septic sources than from agriculture.

The  Vermont Enhanced Implementation Plan for the Long Island Sound TMDL  was added in 2013 to address four goals: 

1. To identify the Vermont sources of nitrogen across broad land use sectors, such as developed, agricultural and forested;
2. To identify the status and trends of important drivers of nitrogen export such as the intensity of agricultural and development activities and investigate how these might have changed since the TMDL baseline period of 1990;
3. To identify the management programs that address these drivers of nitrogen loading that have a significant effect on reducing or preventing nitrogen export; and
4. Using a weight-of-evidence approach, to assess the combined management programs/projects to develop a qualitative evaluation as to whether management efforts are sufficient to meet the original 2000 TMDL of a 10% non-point source nitrogen reduction and if these strategies are sufficient to maintain that control into the future.

Tactical basin plans target restoration efforts to the cause of the water quality impacts.

In partnership with state and federal agencies, regional partners and local organizations working in each sector, implementation projects identified in the basin plan will work to restore and protect water quality and habitat conditions.

Agricultural lands cover only 3.7% of the Basin and contribute an estimated 5% of the Basin's nitrogen load. Recommendations to improve river and stream water quality conditions on agricultural lands in the plan include:

• Increase farm buffer establishment along surface waters and wetlands
• Implement field practices to study N-reduction potential of BMPs and track results of practices implemented
• Provide technical assistance on new climate-smart agriculture (e.g.: Silvopasture, soil health, nitrogen management)
• Work on agricultural lands along the Connecticut River to establish and enhance riparian buffers following the stabilization of water level fluctuations from hydropower production

Recommendations to improve river and stream water quality and habitat conditions in the plan include:

• Support and enhance the riparian buffer and floodplain plantings throughout the landscape
• Remove dams and berms wherever possible
• Increase the number of river and floodplain restoration projects
• Purchase River Corridor Easements for flood resiliency and to prevent land use conversion
• Support targeted strategic wood additions for fish habitat improvement, sediment storage and floodplain connection where these are deemed appropriate

There are 54 mapped dams in the Basin, 49 of which remain in use for recreation, water supply, hydropower production and fire and flood protection. Eleven dams have been breached or removed. Many more are unknown and not mapped. Most of these no longer serve any useful purpose and should be considered for removal to reconnect the rivers and streams for fish passage and sediment movement.

Dams are classed according to their potential to cause harm downstream if they fail. 17 of these dams are classed as either High or Significant Hazards.

Removing unnecessary dams is a high priority in the Basin for stream stability, flood resiliency, and aquatic organism passage.

Recommendations to improve lake and pond conditions in the plan include:

• Promote & implement the  Lake Wise  Program to encourage lake-friendly shoreline property maintenance
• Promote & implement VIP and Greeter programs to help prevent the spread of aquatic invasives
• Establish  Lay Monitoring Programs  on Lakes Sadawga, Grout, and Howe and on Lily Pond
• Work to protect Lily Pond

Wetlands comprise 5% of the total area within this Basin and offer areas rich in diversity. From the floating bog in Lake Sadawga to the rare Black Gum Swamp in Vernon these wetlands are providing wildlife habitat, fish spawning areas, flood mitigation and water quality protection.

Preserving, maintaining and restoring wetlands is a priority for the Basin Plan.

Recommendations to improve wetlands in the plan include:

• Restore degraded wetlands for habitat, water quality improvement and climate change mitigation
• Assess areas of prior converted wetland and hydric soils for restoration
• Assess wetlands for potential reclassification
• Support outreach to towns and the public regarding updated wetlands mapping

The vast majority of the land in Basin 12 is forestland which covers 82% of the Basin. Much of this land is under some form of more permanent protection either being publicly owned, privately conserved or managed under the Use Value Program (Current Use) for forestry. Forest cover is one of the best land uses for the protection of water quality.

Recommendations to improve forest conditions in the plan include:

• Protect headwater streams and sensitive upland surface waters
• Expand the skidder bridge program to make them more available to loggers
• Remove or replace undersized stream crossings with properly sized structures on forest roads
• Conduct outreach on Accepted Management Practices and forest Best Management Practices

The Vermont Department of Fish & Wildlife assesses fishery populations and important nursery areas to document biological and habitat conditions to manage for high-quality recreational fisheries. 

Recommendations to improve fishery conditions in the plan include:

• Scope, design, and implement high priority stream restoration, dam removals and culvert replacements to improve aquatic organism passage and stream stability
• Protect water quality
• Support recreational access to water resources through the establishment and maintenance of stable access areas

Stormwater runoff from developed lands, including the road network, is one of the greatest threats to water quality in Vermont. Urban runoff contributes an estimated 10% of the Basin's nitrogen load to Long Island Sound.

Developed lands cover 6.1% of the Basin, the majority of which is roads. More developed areas of the Basin include Brattleboro, Wilmington and the resort areas around Mount Snow and Hermitage.

Recommendations to reduce stormwater runoff in the plan include:

• Conduct stormwater master planning to identify and implement prioritize actions
• Identify and mitigate sources of bacteria causing impairments
• Address stormwater runoff to Kettle Pond and the Whetstone Brook

 https://dec.vermont.gov/water-investment/cwi/solutions/developed-lands/idde 

The 2020 Basin Plan offered 64 Actions for Implementation and more have been added in the past 5 years. Of these 7 are being carried forward into this updated plan and all others have been undertaken and are completed, in-progress or on-going at this time.

This work is carried out with our partners throughout the region and could not happen without landowners willing to improve their land, streams and riverbanks for water quality and habitat conditions.

Since 2016 the State of Vermont has invested over $18,000,000, in grants and loans for Clean Water improvements in the Basin.

Some of projects that have been completed include:

Removal of a private dam on Cold Brook that blocked fish passage and sediment transport and increased water temperature.

Partners:

• Connecticut River Conservancy
• Landowner

Birge Street Floodplain Restoration, Brattleboro

Identified as a potential flood storage parcel in 2007 this floodplain restoration was competed in 2024 through committed partnerships and funding from many sources.

Partners:

• Vermont River Conservancy
• Windham Natural Resources Conservation District
• Town of Brattleboro
• US EPA
• Many more...

Slide courtesy of VRC

Green River Restoration

A flood destroyed homestead has been removed, the site cleaned up and planted, the riverbank stabilized and the entire parcel protected from future development.

Partners:

• Windham County NRCD
• Windham Regional Commission
• Connecticut River Conservancy
• US Fish & Wildlife Service
• Landowners

Shoreline Restoration - Lake Raponda

The eroded shoreline allowed road gravel and sediment to wash into the lake. The shoreline was restored with soil lifts to provide a base for planting trees and shrubs to prevent road runoff from entering the lake.

Partners:

• Lake Raponda Association
• Town of Wilmington
• Vermont Youth Conservation Corps