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A Creek and a Causeway Serve a Higher Cause
How a Salt Marsh on Georgia’s Sapelo Island is Advancing Scientific Knowledge, Public Policy, and Coastal Engineering

Sapelo Island is the fourth largest Georgia barrier island and one of the most pristine. The reserve is made up of salt marshes, maritime forests and beach dune areas.

A creek, a causeway, and a salt marsh on Sapelo Island, Georgia – the state’s fourth-largest barrier island and one of its most pristine – are revealing much to scientists, policy makers, and regulatory authorities about salt-marsh ecology. This is important because the Georgia coastline, while little more than 160 kilometers (100 miles) long, accounts for nearly a third of the total salt marsh on the U.S. East Coast.

Dean Creek meanders through the remote marsh that leads to the public beach on the south end of Sapelo Island, which is one of the 27 National Estuarine Research Reserves (NERR) that NOAA administers in partnership with states, universities, and nongovernmental organizations. The system of NERRs was established for long-term research, education, and coastal stewardship.

The causeway crossing over Dean Creek is not what one would call heavily traversed – the island is home to only 70 year-round residents and hosts some 30,000 annual visitors.

A Wide Breadth of Science

Dorset Hurley leads a field crew in a marsh setting.

Dorset Hurley, the research coordinator at NOAA's Sapelo Island National Estuarine Research Reserve, leads a field crew in a marsh setting.

“This marsh is helping us understand how causeways and culvert systems affect marsh processes,” says Dorset Hurley, research coordinator of the Sapelo Island NERR. He explains that the causeway that bridges Dean Creek has impeded the normal flow of the tide into and out of the marsh’s upper (northern) 58 acres, due to an associated culvert system. The system is comprised of three five-centimeter (two-inch) -diameter pipes that were placed there for drainage.

The causeway was built back in the 1950s to allow easier access to the nearby ocean front. “This was a common practice until recently,” says Hurley. “Causeway construction is no longer permitted in coastal Georgia, but many older ones remain.”

“We realized that this was an ideal site to conduct a wide breadth of science that could potentially inform public policy and coastal engineering in Georgia and other coastal areas,” he continues. In 2004, Hurley began a project to fully evaluate Dean Creek’s biology (e.g., plant species, abundance, and location), water quality, water flow (hydrology), sediment processes, and underlying structure (morphology), using techniques both conventional and cutting-edge.

Although the work was, at times, sporadic and poorly funded, “A very clear picture of the marsh began to emerge, both in terms of its natural processes and the causeway’s hindrance of them,” he says.

Research Informs Restoration

Sapelo Lighthouse, constructed in 1820, suffered serious damage during a hurricane in 1898. It was restored in 1998 to its present condition.

The project has gained recognition from the individuals and agencies responsible for maintaining the Marshland Protection Act in the State of Georgia.

“Dean Creek is in a culturally significant place and it requires infrastructure ‘retrofitting’ in the form of a new bridge span,” Hurley notes. “And now, the well-developed spectrum of science has made the site so attractive to both government and industry that it seems only natural to focus restoration efforts here.”

Recently, a liquid natural gas company, which had to offset minor damages associated with its holding facility in the Savannah River basin, about an hour north of Sapelo, has volunteered to fund construction of the bridge.

Benefits Both Ecological and Economical

This project illustrates the collaboration and innovation that underpins all of NERRS’s work, says Hurley, who is himself employed through a NOAA-State of Georgia partnership agreement. He gratefully acknowledges the tireless efforts of his many partners to characterize the Dean Creek marsh and then use the information to inform and advance policymaking, first at the state level and, eventually, beyond.

“Causeways were built in coastal areas for at least 200 years,” he notes. “We know that they disrupt marsh processes, but until now, we have not been able to quantify that. We are discovering a lot about how salt marshes function from Dean Creek, and, equally importantly, we are learning to restore them in ways that make good sense both ecologically and economically.”

Dorset Hurley (right) immerses himself in the seeding of commercially grown oyster spat – one of his many scientific endeavors as the senior marine biologist and research coordinator at Georgia’s Sapelo Island National Estuarine Research Reserve.

For More Information

A Creek and a Causeway Serve a Higher Cause How a Salt Marsh on Georgia’s Sapelo Island is Advancing Scientific Knowledge, Public Policy, and Coastal Engineering

A Wide Breadth of Science

Research Informs Restoration

Benefits Both Ecological and Economical

A Creek and a Causeway Serve a Higher Cause
How a Salt Marsh on Georgia’s Sapelo Island is Advancing Scientific Knowledge, Public Policy, and Coastal Engineering