Crosby Brook Degradation

Information on concerns with pollution in Crosby Brook

Crosby Brook

Crosby Brook follows Middle Road toward Brattleboro where it joins with the southern branch of Crosby Book which follows Black Mt. Rd. to where the two brooks merge into one underneath the I-91 intersection and then empty into the CT. south of Rt. 9 east bridge.

There are concerns about the quality of the water in Crosby Brook when it enters the Connecticut River.  These concerns and preliminary information related to these concerns are included in a preliminary report The Biological Condition of Crosby Brook and Exploration of the Environmental Stressors on the Aquatic Communities developed by the Vermont Department of Environmental Conservation Water Quality Division, Biomonitoring and Aquatic Studies Section.  For a copy of this report, e-mail maryellen@svcable.net.

Following are excerpts from the report:

Crosby Brook is a direct tributary to the Connecticut River located in the southeast corner of Vermont, within the towns of Dummerston and Brattleboro. The headwaters are located in the hills of Dummerston at an elevation of about 1000 ft, and its mouth is in Brattleboro just below the Rt 9 Bridge to NH at about 230 ft. The brook flows for about 6 miles with an average grade of 1%. The entire CB watershed area is 15 km 2 and is divided into two primary sub-watersheds. The larger is considered Crosby Brook (CB) proper, with a watershed area of 9.5 km2, above their confluence. The smaller of the two is referred to in this report as the S. Branch Crosby Brook (SBC), with a watershed area of 4.5 km2. The SBC joins CB immediately below the I-91 exit just above the junction of Rt 5 and 9.

Crosby Brook is classified as Class B/Coldwater fish habitat water pursuant to the Vermont Water Quality Standards. Since I-91 was completed in the 1970’s land use within the lower part of the watershed has exhibited a trend of conversion from agricultural use to residential and commercial use. The I-91 project was responsible for a relocation of stream reaches on both the main stem and S. Branch Crosby Brook. Some historical accounts refer to the brook as Black Mt, and Sergeant Brook. We have used Crosby Brook at the request of the Dummerston Conservation Commission.

This report will first give a biological assessment and an interpretation of the community fingerprint based on the biometrics affected, species composition and habitat observations by site. Secondly, based on the assessments, and community stressor fingerprinting, data for a number of the most likely water quality stressors on the aquatic communities is presented under the stressor section. Finally, a discussion of the potential sources of the water quality stressors on the aquatic biota is presented.