Central Vermont Regional Planning Commission Conducts Class 4 Road Erosion Remediation and Demonstration Project

In an effort to demonstrate the importance of municipalities addressing significant erosion sources from Class 4 roads, the Central Vermont Regional Planning Commission (CVRPC) conducted a remediation and demonstration project in the Towns of Calais, Moretown, and Worcester. The project was funded by a grant from the Vermont Department of Environmental Conservation (DEC), the Lake Champlain Basin Program, and the U.S. Environmental Protection Agency (EPA). The primary objective of this project was to reduce sediment and phosphorus runoff by implementing road Best Management Practices (BMPs) on hydrologically-connected municipal road segments, specifically Class 4 roads, within the Lake Champlain watershed. Hydrologically-connected road segments are those sections of road at high risk to impact adjacent lakes, ponds, streams, and wetlands. Secondary benefits of implementing road BMPs are improved flood resilience and road safety.

Each town was awarded a portion of the grant funding and a share of the segments. Calais worked on 8 segments, Worcester worked on 7 segments, and Moretown worked on 11 segments. In August, CVRPC and DEC staff, with the support of the participating towns, held two public workshops. The workshops highlighted the BMPs utilized to address significant erosion sources from Class 4 roads, the construction costs and time expended for implementing the specific BMPs installed by road and segment, and how each road segment now meets the new Vermont Municipal Roads General Permit (MRGP) standards. Site visits to the specific demonstration project areas showcased the work completed. Thirty-one people attended the workshops, excluding CVRPC and DEC staff. By sharing the project remediation and demonstration components and having a “lessons learned” discussion, other municipalities across the state learned how to replicate the Class 4 road erosion BMPs.

BMPs implemented during this project included: drainage culvert upgrades, turn out installations, culvert outlet stabilizations, culvert headwall stabilizations, grass and stone-lined drainage ditch installations, roadside berm removal, and road resurfacing.

All of these practices promote road stormwater disconnection, infiltration, and conveyance stability. Overall, 26 segments of hydrologically-connected Class 4 roads were brought up to MRGP standards: 1.6 miles of road was resurfaced with new gravel, eight new stone-lined turn outs were installed, eight new culverts were installed with new or improved headers, and 5,800 linear feet of stone-lined and grassed ditching were installed.

CVRPC, DEC, and the participating towns would all agree that the Class 4 road erosion remediation and demonstration project was a success. Not only did the project reduce water quality impacts of the roads on nearby waterways, it also improved flood resilience and reduced road maintenance costs. The Town of Calais reports that the work done on Apple Hill Road in 2017 has significantly reduced maintenance costs caused by road washouts. The project team expects to see similar resilience with all the BMPs installed for years to come. The work done under this project, to find and correct 1.6 miles of severe erosion on Class 4 roads, offers a great opportunity to all Vermont towns to better understand how and why they should approach fixing severe erosion on their own Class 4 roads.