Assistance is Available for Erosion Control
Road managers are aware that they can prevent erosion by stabilizing disturbed areas, creating vegetative buffers, and installing culverts but do not always know how to undertake an erosion control project. There are resources available for assistance to control runoff and erosion. Municipalities with a year round population of less than 10,000 can receive free engineering help. Larger communities can receive help for but must reimburse for some expenses.
County Conservation Districts and Natural Resource Conservation Service (NRCS) offer practical ideas for controlling runoff. When a municipality has identified a problem, it should contact the Conservation District who will do a site visit and field survey. After completing the survey, they crunch numbers and develop two or three alternatives. They prefer to create alternatives that have the least impact on the environment. The frequently recommended alternatives are to: increase culvert size, increase ditch size, line ditches, and/or plant vegetation.
County Engineers are also available to help with smaller projects such as sizing a culvert. Another source for technical assistance is the Lake Winnipesaukee Watershed Project (LWWP). The primary goal of the watershed projects are to control non-point source pollution, which results from water runoff that washes over land. Snow melt and storm water runoff can cause sediment and contaminants to enter lakes, rivers, and streams.
One example of a municipality who received technical assistance was the Town of Center Harbor. Each spring the beach would erode and sink holes would develop due to groundwater and storm water flows. The LWWP was the liaison between Center Harbor and the conservationists from NRCS to provide Center Harbor with a complete set of plans to resolve the erosion problem.
The plan included underdrains, a closed drainage system, a diversion swale, and a level spreader outlet. According to Jeff Haines, the Center Harbor Road Agent, they “haven’t put the drainage system into the ground yet because the use of the property might change in the next 2 years. There are sections of the system might be phased in this year.” When Center Harbor crews begin work, the LWWP staff will come back to help lay out the system.
For more information on NRCS, visit their web site at: http://nhst02.nh.nrcs.usda.gov/