To widen and realign I-84 through Waterbury, a river, a brook, and a stream were realigned or relocated. These watercourses, identified as receiving waters along this section of I-84, include the Mad River, Beaver Pond Brook, and several named and unnamed tributaries. Below are the watercourse realignment details:

• Realignment and stabilization of the Mad River channel from south of the existing EB 25 Off-Ramp to Harpers Ferry Road to north of Plank Road to accommodate roadway widening and realignments and new bridge crossings.
• Realignment of Beaver Pond Brook channel in the Scott Road area to allow for a revised alignment of the WB 25 Off-Ramp, necessary to realize traffic safety and operational improvements at this interchange.
• Relocation of East Mountain Brook at its confluence with Beaver Pond Brook to accommodate the I-84 relocation and widening and Reidville Drive relocation.
• Re-establishment of a Perennial Stream in the Mountain Village Road area.
• Extensive in-stream habitat enhancements associated with the watercourse relocations.

The project impacted approximately 2,347 m (7,700 feet) of watercourses and 0.5 hectare (1.3 acres) of wetlands. The mitigation for the watercourse impacts were accomplished within the project limits through eliminating obstructions to fish migration and extensive in-stream habitat enhancements. Based on the mitigation strategy and mitigation ratios accepted by the US ACOE, the project provided approximately 1.2 hectares (3 acres) of restored or newly created wetlands.

The design of these relocations has incorporated habitat enhancement measures intended to improve habitat and fish passage potential, integrated with channel structural grade stabilization elements.