Southeast Watershed Alliance's Stormwater Standards

It’s widely understood that in areas with faster rates of development the spread of the impervious surface is increased. Impervious surfaces are areas that don’t let water infiltrate into the ground like parking lots and roofs.


Stormwater Pollution running into a stormdrain

Because water can’t infiltrate it runs off and it picks up all the dirt, litter, oils and pollutants with it and this results in elevated levels of pollution into our waterways – this is stormwater pollution. Not only is stormwater a pollution concern but it can also lead to flooding and failure of town bridges, culverts and roads. Stormwater is recognized as the main cause of pollution for up to 83% of the waterways in NH that fail to meet standards for clean water.

Our communities are increasingly confronted by the challenges of managing development and allowing for economic growth while also protecting the environment and planning for increasing frequency of extreme storm events which all combine to stress local waters, municipal roads, bridges and buildings and public health and safety. In response to these challenges the Southeast Watershed Alliance (SWA) through grant funds provided by the NH Coastal Program, part of the NH Department of Environmental Services, contracted the Rockingham Planning Commission and the UNH Stormwater Center to develop updated stormwater management standards to provide a consistent and effective level of management that each of the 42 towns in the coastal watershed could adopt as either a zoning ordinance and/or land development regulation and that could meet the needs of both the community and the environment.

The goals of this effort is to effectively and efficiently:

  • Control non-point source pollution from future development and land conversion through the use of filtration, like tree box filters and infiltration practices like gravel wetlands.
  • Mitigate and reduce runoff and non-point sources of pollution from existing development through redevelopment guidelines.
  • Manage the quality and quantity of water resources.

This effort is a great step in the right direction to addressing the main cause of our region’s pollution problem. Our communities should be encouraged to adopt these standards and move towards a more resilient and healthier watershed.

The model stormwater management standards are available here

For more information about SWA & their great work click here.

PREP is part of the U.S. Environmental Protection Agency’s National Estuary Program, a joint program between local, state and federal agencies established under the Clean Water Act with the goal of protecting and enhancing nationally significant estuarine resources. PREP is supported in part by an EPA matching grant and is housed within the School of Marine Science and Ocean Engineering at the University of New Hampshire.