Stormwater Action Plan

Stormwater management is essential for the safety of residents, infrastructure, and ecological functioning. Municipal, state, federal, and private partners all play a role in maintaining and improving the functioning of both human and natural systems. UVLSRPC provides GIS-based culvert assessment program to map and prioritize culvert systems in need of improvements or maintenance, as well as spatial data maintenance and training for municipal staff. UVLSRPC also hosts residential storm water workshops with interested communities to educate landowners on stormwater management best practices.

In 2025, UVLSRPC received a Long Island Sound Futures Fund grant. This grant seeks to achieve nitrogen reductions within the Connecticut River watershed to reduce a “dead zone” within the Sound due to nitrogen and pollutant runoff from upstream. Our project area is the Greater Upper Valley as shown on this map. Our grant project is to promote and assist the development of green stormwater infrastructure (GSI) within the project area.

We partnered with the Mount Ascutney Regional Commission (MARC) and the Two Rivers Ottauquechee Regional Commission (TRORC) to include Vermont in our regional analysis for reduction of pollutants discharging into the river between our states. We also included the Connecticut River Joint Commission, the Connecticut River Conservancy, and the bi-state region municipalities for project input. We hired Weston & Sampson, Engineering & Environmental Consulting to assist with this project.

Green Stormwater Infrastructure (GSI) is a nature-based management of rainwater where it falls using soil, plants, and permeable materials to filter, absorb and slow runoff. It reduces sewer overflows, floods, and pollution while adding green space. Common examples include rain gardens, infiltration trenches, and permeable pavement.

Low Impact Development (LID) is similar to GSI in some ways depending on what definitions are used. Both management systems use nature-based approaches to manage stormwater runoff though LID often focuses on site design to mimic natural hydrology and GSI emphasizes engineered systems like rain gardens. These are complementary methods with similar goals to reduce the impacts of stormwater by using natural systems.

Our program includes:

Site Identification and Evaluation: Municipalities within the Connecticut River watershed were contacted to develop a list of potential sites which could benefit from a GSI project. We have evaluated 101 sites within the 58 municipalities in New Hampshire and Vermont. Our goal was to select at least two sites in each municipality within the watershed for initial desktop evaluation. These sites were then analyzed and scored based on feasibility, co-benefits, and potential nutrient (including nitrogen) reduction. The feasibility assessment included maintenance effort and frequency and upfront cost of the GSI. The co-benefits included flood reduction, slope stabilization, and public education and aesthetics. Download the final list of all sites (56.6kb).
Preliminary Design, Engineering, and Permitting Preparations: Our project goal was to identify the top 10 sites in New Hampshire (coming soon) for further design, engineering, and permitting to create “shovel-ready” projects with designs that can be transferable designs for other towns for their projects. Municipalities could then seek funding to pursue construction of these green stormwater infrastructure recommendations—or build them with municipal staff. We have provided funding resources (see below) for the actual construction and can assist our municipalities with construction funding applications if they want professional assistance. Our Vermont partners will apply for other funding to perform the design, engineering, and permitting.
Regulatory Review: A thorough review was made of all relevant regulations, ordinances, plans, and other documents for each municipality within the Greater Upper Valley region for this project. The results of the review can be downloaded here (44.0kb). The review was to flag any references to GSI or low-impact development (LID) including the assets and barriers for GSI/LID. The results show that more work need to be done in municipal regulations to encourage more post-construction stormwater work to reduce runoff from properties to roads, streams, and abutting properties.
Community of Practice (Outreach and Training): GSI is often not well known in our communities. Our Community of Practice program will provide a recorded webinar (available after August 2026) for municipalities for creating or amending regulations, ordinances, plans, and associated documents to create more friendly requirements and guidance for GSI. There were also on-site trainings for Road Agents, Department of Public Works Staff, and Selectboard members to visit sites with existing GSI systems. These trainings were held in May 2026 at the Black Community Center in Hanover, NH and at the Mount Ascutney Hospital in Windsor, VT.
Stormwater Action Plan: A stormwater action plan will seek to frame the challenges and opportunities faced by the Region in implementing GSI and LID strategies within the target communities of the watershed. The plan’s primary purpose is to act as a living document for bi-state collaboration and to further stormwater goals with alignment to nitrogen loading reductions or preventions. This plan will include both a New Hampshire and Vermont Model Stormwater Ordinance to promote GSI and LID. You can access them below or in the stormwater action plan.