By: Brendan Newell, Great Bay NERR
(with contributions from Cathy Coletti & Kirsten Howard, NHDES Coastal Program)
Durham, NH – Standing on the beach at Wagon Hill Farm in Durham, NH, it’s easy to appreciate the natural beauty of coastal NH. From this vantage point, you can look across Little Bay, and depending on the tide, you will see (and smell) expanses of mud flat or blue water dotted with boats and kayaks. You might see terns diving for fish, hear an osprey’s call or the rattle of a woodpecker working in nearby oaks and pines. You will likely notice something else – you are not alone.
Kids, dogs, and a shrinking shoreline
Wagon Hill Farm, purchased and conserved in 1989 by the town of Durham, is often a busy place filled with dog walkers, families and picnickers to name a few. The property, conserved for public access and the protection of scenic views, wildlife habitat, and water quality, boasts rolling hills, stands of forest, a historic farmhouse, trails, and a community garden. It also features 1,600 feet of diverse shoreline where Little Bay meets the mouth of the Oyster River. This shoreline is made up of narrow bands of sensitive saltmarsh habitat, rocky outcroppings, and steep, tree-lined banks, as well as a small, maintained beach area. It’s not hard to see why this beach, which offers a mowed grass picnic area to the north and overlooks Little Bay to the south, is a popular spot for human and canine visitors alike. So popular that the very land under foot (and under paw), is threatened by the heavy traffic.
Erosion is a normal occurrence along shorelines, especially in places like Great Bay, where the large tidal range drives fast currents, and harsh, icy, winters cause chunks of the shore to break off and be carried away. But the erosion taking place at Wagon Hill Farm, particularly along the shoreline of the beachfront picnic area, is not all natural. Visitors have long been finding their own pathways to the water from the shoreline’s adjacent trails, trampling the plants that stabilize the land and packing down the soil along the way. These rogue paths facilitate fast-flowing rainwater to wear away the shoreline as it moves from the land to the bay. Add powerful wakes from boats that frequent the bay and the Oyster River, and there have been startling amounts of erosion along the entire property, with the edge of the beach moving back more than six feet since 2003.
Please don’t take the road less traveled
Simply conserving the Wagon Hill Farm property is not enough to protect it from being loved to death by the people and pets that enjoy recreating here. In order to protect the shorelines of Wagon Hill farm, the property managers at Durham’s Department of Public Works have to put in extra effort.
Along trails throughout Wagon Hill Farm, signs designed by a 5th grade class from the Oyster River Middle School educate visitors. This sign teaches about erosion by pointing out trees that have toppled into the water and marsh because of erosion. Credit: Brendan Newell.
In an attempt to curb erosion, in 2003, Durham’s Department of Public Works took action along the Wagon Hill Farms shoreline. The Department installed clear walking trails that offered water views while discouraging people from creating their own paths. At the beach area, more sand was added and it was made slightly larger to improve access. In addition, fences and signs were installed along the rest of the shoreline to encourage people and their pets to only use the beach to get to the water. To reinforce the marsh, a few hundred plugs of cordgrass were planted. According to Mike Lynch, Durham’s Director of Public Works, these actions have helped slow erosion, but it is still occurring at an alarming rate, and more needs to be done.
Since 2003, Durham has moved the fence back three times, as the shoreline erodes in front of it. The most recent move happened in July, when the fence was set back 25 feet from the current shoreline. The fences and sign ask visitors to stick to the beach area and stay off the “sensitive shoreline.” But is this message getting through?
I visited Wagon Hill Farm on a sunny Sunday August afternoon and over the course of an hour and a half more than 20 people and four dogs visited the beach. Many of these visitors wandered off the beach onto the marsh. I spoke with two women who had just finished collecting seaside lavender (which, by the way, is illegal under New Hampshire wetlands laws) from the marsh next to the beach.
They told me they had come from Dover to “enjoy the view,” and explained that they were unaware that the shoreline they had just walked along was eroding. “We didn’t see the sign so that means it’s not enough of a sign…because we would honor that, we would never have walked there.”
They suggested more fencing be added to eliminate confusion about where people should and should not walk.
Time to invest in smart erosion control
More action needs to be taken to save Wagon Hill Farm’s shoreline, and Lynch sees momentum building in Durham. The town recently finished paying off the 20-year bond used to purchase the property in 2009, so until now more resources to curb erosion have been hard to come by.
“Now that the bond is paid off,” Lynch says, “it has been more on the radar screen; the Durham Land Stewardship Subcommittee discusses it at every meeting.”
And in fact, on December 14, the Durham Town Council approved the Fiscal Year 2016 budget which includes $368,250 allocated for a Wagon Hill Farm shoreline erosion mitigation project. According to the Durham Friday Updates, the project will require consultation with the Conservation Commission, Land Stewardship Subcommittee, and Parks and Recreation Committee and with the advice and consent of the Town Council. Funding of this project includes a tentative $170,000 from the Eversource Seacoast Reliability Project as wetland mitigation (although it would have to be approved on its merits and allotted as such by NHDES), $115,350 from the Wagon Hill Farm – L. Brown Trust Fund, and $82,900 from bonding. If the $170,000 from Eversource is not ultimately allotted for this project, it will be contributed by Eversource to a fund held by NHDES for general wetland mitigation work/land conservation in the region.
Because the property’s shorelines are diverse, with marshes, tree-lined banks, and rocky areas, there is no one size fits all solution. But currently a number of site specific solutions are being discussed including redesigning trails, adding more fencing, and adding boardwalks to allow access and views without foot traffic directly on the land. Some have suggested armoring areas that are hit hard by boat wakes with large rocks or retaining walls or regrading banks and restoring the marshes. Research shows that using more natural solutions like marsh restoration and enhancement can provide better protection from wave energy and storm damage, preserve biodiversity, and allow the system to adapt to changing conditions in ways that hardened shoreline strategies do not. These natural solutions are sometimes called “living shorelines.”
David Burdick, interim director of the Jackson Estuarine Laboratory has visited the site and wrote in an email:
“It would be an ideal spot to try out a living shoreline project where we place a rock sill in front of the marsh to reduce ice scour and wave energy from boat wakes that are contributing to the erosion. With the help of some marsh planting, the shoreline would stabilize. We could also think about seeding the rock sill with shellfish to enhance biodiversity, clean the water, and provide some added protection from erosion.”
Lynch is currently working hard to find funding for whatever combination of solutions is chosen, saying, “It’s time to invest in erosion control at Wagon Hill Farm.”