Watershed Improvement Projects

Since the late 1990's, LSPA has been awarded grant funding for a number of water resource protection projects. 

Federal Clean Water Act (Section 319) funding - administered through the New Hampshire Department of Environmental Services (NHDES), the NH State Conservation Committee (Moose Plate Program), the National Oceanic and Atmospheric Administration, and the Davis Foundation (a private Maine foundation) - have all contributed to make these projects possible.

LSPA has also facilitated and helped to fund local other small (non-grant ) projects. These projects would not be possible without the local partners, collaborators and in-kind contributors (services, materials, equipment) listed below:

  • Town of New London, Public Works
  • Sunapee Highway Department
  • Town of  Newbury
  • NH Department of Transportation, District 2
  • Mount Sunapee Resort
  • Local Environmental Engineers - Charlie Hirshberg, CLD Engineering, Sunapee
  • Peter Blakeman,  Blakeman Engineering, Sutton
  • Twin-Lakes Villa
  • Indian Cave Associations


Sunapee Stormwater Infrastructure Project

LSPA partnered with Antioch New England Graduate School, University of New Hampshire, and consulting engineers and scientists  on this two year grant project funded by the National Oceanic & Atmospheric Administration (NOAA). 

Graduate students, researchers, LSPA staff and volunteers gathered field data on stormwater infrastructure in the watershed.  Higher intensity and higher volume storms have been occurring, particularly in the northeast, and more are projected for the future.  This project  was a proactive approach to help prevent culvert and road washouts, protect water quality, and protect public and private infrastructure. 

Culverts  in each of Lake Sunapee's  sub-watersheds were analyzed for their capacity to safely carry runoff from current storm events and runoff levels from projected storm events.   The great majority of culverts met capacity requirements for current 25-year storm precipitation levels under current development conditions.  With projected precipitation levels and future development increases, many culverts will be undersized. 

One of the valuable tools gained from this study was a list of culverts for each of the watershed towns with each culvert's estimated vulnerability.  In effect, each town has a "prioritized" culvert replacement list to use as a guide.  This will help the public works departments schedule and budget for these projects, prevent emergency replacements, and save money over time.

Another "tool" resulting from this project is that the towns are also sharing culvert inventory information. In the event of an emergency replacement, the inventory may help with properly sized culverts being immediately available.

There was a great deal of public and municipal involvement in this project. There were participatory as well as educational  meetings and events that were well attended. 

Section 319 Grants: Clean Water Act Funding administered through NHDES

Two grant projects that addressed non-point source pollution (NPS) were completed several years ago. These two projects, the Sunapee Watershed NPS Grant  and the  Sunapee Roadways Grant addressed multiple issues at various sites throughout the watershed but were focused on minimizing impacts caused by erosion and road-related runoff.

The completed work included streambank stabilization and restoration, stormwater management  and infiltration, sediment trapping  and retention, and treatment wetland creation. 

The project sites included Kidder Brook in Springfield, Mount Sunapee Resort ski area parking lots and maintenance areas, Eagle Rock Brook, Route 11 in Georges Mills, Sunapee Harbor, Hastings Landing, and others.

Sunapee Swirler

An earlier 319 grant- funded project that was focused on minimizing water quality impacts of road runoff/stormwater resulted in the creation of the so-called Sunapee Swirler. The Swirler  is a slightly modified stormwater catch basin that has improved fine sediment retention capacity.  The Swirler was installed at several "difficult" sites where there were no  alternative measures to divert,  collect and/or treat (e.g., infiltrate) stormwater. These sites were typically totally paved over, and /or in very tight conditions where larger surface measures such as infiltration basins were not possible to install.

The Swirler is a large, deep round concrete basin with added in-flow, retention, and  outflow fittings/components.  Incoming stormwater is forced to flow around the interior wall of the basin.

Outflow exits include a "tee'd" pipe located in the center of the basin. Heavier sediments tend to fall toward the basin wall, and floatable materials (including oils, etc.)  are retained by the tee.  In the circular flow, finer sediments tend to migrate toward the basin center.  More of these fine sediments are retained (than a standard catch basin) by a cylinder (such as a 3-foot diameter well tile) that sits at bottom center. The cylinder creates a space of  less current and motion that allows the fine sediments to settle rather than remain in suspension.   "Swirlers" have been installed in Sunapee Harbor, Burkehaven, Hastings Landing, Newbury Harbor, and near Pleasant Lake in collaboration with Sunapee and New London Highway Departments and the NH Department of Transportation.

Sunapee Harbor - Garnet St.

Collaborating with the Sunapee Highway Department, Indian Cave Landing Association, and Overlook at Indian Cave Owners Association, LSPA assisted in installing a large sediment basin on Garnet St. near the Harbor. 

Tons of sand and sediment from street runoff had been entering the lake from Garnet Street creating water quality issues as well as decreasing water depths at existing docks.  A large capacity basin with an internal baffle to help retain sediment was installed in 2010, helping to reduce sediment deposition into the Harbor.

Current and Future Planned Projects

LSPA is currently working  to reduce stormwater impacts to Beck Brook at Mount Sunapee Resort with several partners including  Mount Sunapee Resort, NH Fish & Game and Trout Unlimited.