Bay Towns Band Together To Manage Shoreline

BREWSTER – A grain of sand knows no boundaries when it’s blown or washed upon a forsaken shore.

With that in mind, it makes sense for towns to disregard manmade lines on a map when contemplating what to do about erosion and tides eating away at our coastline and reconstructing our beaches.

Orleans, Brewster and Dennis have banded together with the Center for Coastal Studies in Provincetown to explore a regional approach to managing the shores of Cape Cod Bay since sand is being carried both east and west from Dennis.

The Center For Coastal Studies presented their findings at the meeting of the Brewster Conservation Commission June 25. Steve Mague, the program director of the Coastal Geographic Research and Applied Sciences Program at CCS, and Samantha McFarland, the assistant director, said the work is just the first part of what they expect will be a longer study.

“This is the initial phase of what we hope to be a multiphase project funded through Coastal Zone Management’s Coastal Resiliency program,” Mague said.

Work was done by CCS, Brewster Director of Natural Resources Chris Miller (the project manager), Aaron Burnham from Dennis, Nate Sears from Orleans, Bill Grafton from Brewster (The town’s conservation administrator), Cassie West, John Ramsey and Andy Sedaris as well as Steve McKenna of Brewster, the regional CZM coordinator.

A regional approach like this hasn't been done elsewhere in the state.

“We’re looking to maximize the ability of the towns to work with natural processes and drivers of coastal change,” Mague said. “We’re also trying to maximize the potential of the shorelines to use their natural ability to respond to coastal hazards independent of town boundaries.”

The object is to get everyone on the same page pulling in the same direction.

“There’s cost efficiencies and savings when you have three towns working together,” he added. “And a greater chance of leveraging grant opportunities.”

The hope is that the regional approach can be applied locally, with each town retaining jurisdiction over its own wetlands.

“Because the natural shoreline resiliency is dependent on the ability of coastal landforms to erode and supply sand to the system and to downdraft coastal wetland resource areas, we wanted to use the concept of littoral cells to organize our framework spatially,” Mague said.

A littoral cell is a natural coastal compartment that doesn’t recognize town boundaries — like a bay or beach — that contains a complete cycle of sedimentation, sinks, paths and sources.

Looking at data from 1933 to 2010, there is a source area around corporation beach in Dennis that transports sand west into Barnstable Harbor and also eastward to Brewster and Orleans in the Skaket Beach Rock Harbor area about 12 miles away.

This phase of the project updated the coastal structure inventory, did beach nourishment research and developed a shoreline management framework. Coastal structures (rock walls, etc.) cover about 3.75 miles or 25 percent of the zone studied (Barnstable Harbor to Rock Harbor). There are 39 groins blocking sand movement, including 29 in Brewster. They looked at records of 386 properties along the shore.

“We were looking at records that are over 50 years old,” Mague noted. “And we could see how folks were trying to wrestle with the problem of nourishment and what to do about mitigating the impacts of sea walls. There were different methods of requiring nourishment, there were a variety of frequencies, the volume requirements were subject to monitoring and benchmarks and it became very complicated to figure out. How in the world do you enforce these and know what is still in play?”

They also found a lack of compliance. Utilizing an annual parcel-based nourishment volume model developed by Coastal Zone Management, they determined the total demand for nourishment is about 20,000 cubic yards a year with about 4,000 cubic yards in the littoral cell towards Barnstable Harbor and 16,000 cubic yards going towards Brewster and Orleans. That’s how much would be supplied by natural processes.

Looking at the desired management framework, Mague and his team looked first for similarities in regulation and management approaches in the three towns. The state and local wetlands bylaws make a nice framework, Mague said, “particularly if we’re trying to promote the flood control and storm damage functions of coastal wetlands.”

They came up with 25 core management principles and policies the towns can use in a regional approach. They focused on plan and application standards. The work emphasizes the importance of sand for coastal resiliency.

The result should be a regional approach with responsible stewardship of the shared shoreline.

“These towns need to have a basic understanding of the baseline conditions that relate to the physical characteristics of the shoreline and its adjacent areas as well as any human alterations,” McFarland said, so she created an inter-municipal shoreline management database from 550 sets of data.

“The idea is to have a one-stop shop for general information that could be useful to coastal managers in a variety of situations,” she said. “A big advantage of having this information in a spatial format is the ability to overlay data.”

Properties are marked off if residents are year round or seasonal, what their beach nourishment requirements might be, nourishment volumes and conditions, elevations, high water markings, structures present, historic and current salt marsh mapping, sediment transport information and more, up to 18 different data sets.

“The project team is hoping to maximize the use and application of this data in a manner that fosters continued open collaboration between this town partnership, other organizations and the general public” McFarland said. “Second, we would like to create an online regional resource with this data that includes a repository of interactive maps and spatial applications that can aid town staff in their assessments.”

To facilitate that they are hoping for a phase two of the grant.

“I’d like to commend the three towns for this work. They took the initiative to seek the funding,” said Steve McKenna, CZM’s Cape Cod and Islands regional coordinator. “This kind of information doesn't exist for any other communities other than the four outer Cape. Managing the shoreline regionally is a fantastic concept.”