Policy Initiatives: Coastal Initiative: Nourishment

By David Godfrey

In the southeast United States, there is a growing battle being waged by coastal developers, beachfront property owners, the tourism industry and public officials in an attempt to hold back the rising sea and steady the constant ebb and flow of sand along the shoreline. In the process, the tactics being employed to achieve this expensive and never-ending task often put sea turtles and other marine species at risk. It is a complicated issue, to be sure, and nowhere is the issue more volatile than along Florida’s rapidly developing east coast.

On the beaches of Florida’s Atlantic shore, threatened and endangered sea turtles nest in densities greater than those found anywhere else in the United States. Competing for this prime habitat are millions of Florida residents who are living and rapidly building on the shore. At the same time, the forces of sea level rise, violent storms, natural erosion or sand displacement caused by various forms of shoreline alteration combine to threaten the permanence of structures built on the beach. In an attempt to stabilize human infrastructure on the coast, two main engineering tactics are being employed. The first is coastal armoring—literally the building of walls along the dune line to temporarily halt the erosion of sand from behind the wall. The second tactic involves building up the beach, “beach nourishment,” by placing new sand on the shore.

In the pages of its newsletter, the Sea Turtle Conservancy (STC) has often written about the negative consequences associated with coastal armoring. Indeed, STC has spent considerable time and resources trying to stop the spread of armoring on sea turtle nesting beaches. Furthermore, STC has often encouraged local, state and federal agencies to use beach nourishment as an alternative to sea walls. Certainly, both tactics pose serious consequences for sea turtles and other aquatic and upland species. But of the two, the placement of additional sand on the beach is the lesser of two evils—and may at times even create turtle nesting habitat where erosion and development have combined to eliminate all suitable habitat for turtles. However, sand nourishment is not without its own set of damaging impacts, and project planners so far seem intent on ignoring many of the long-term consequences associated with these projects.

Given that Florida is now embarking on one of the most expensive and elaborate beach restoration schemes in history, it is essential that impacts to sea turtles and other marine organisms are given careful consideration. No matter what name is used—sand nourishment or beach restoration—these projects are literally large-scale coastal dredge and fill projects. Sand and other hard substrates, typically from offshore “borrow” areas, are sucked up by large vacuum-wielding dredges and dumped on the shore. Bulldozers then spread the dredged material along the beach and shoreline, attempting to mimic the natural contour of the shore.

These projects impact sea turtles in numerous ways. The dredges often suck up and kill unsuspecting turtles resting on the bottom of the sea. If conducted during nesting season, viable nests can be buried over when surveys fail to locate every nest before sand is pumped onshore. When nests are moved, hatching success is often lower in the relocated nests—thereby causing a “take” of otherwise healthy hatchlings. The dredge material dumped on the beach is often far different from the “natural” beach, which alters nesting behavior and skews sex ratios in hatchlings. With careful planning, however, these particular impacts can often be minimized, and STC is working hard to make sure these issues are adequately addressed in the planning process.

The issue becomes more cloudy, however, when you look at the impacts to offshore habitats. The importance of sand “borrow sites” to sea turtles and other organisms is largely unknown. In addition, as we are seeing with projects proposed for the east central coast of Florida, important nearshore reefs can be completely buried over during the nourishment project. Studies by Dr. Llew Ehrhart and his students at the University of Central Florida show that some nearshore reefs provide extremely important developmental habitat for juvenile turtles. In fact, some near the Archie Carr Refuge in Florida appear to be among the most important in the world. The recurrent burying of these habitats is certain to have cumulative harmful impacts to sea turtles, as well as numerous fish species.

As with all other large dredge and fill operations, a federal Environmental Impact Statement (EIS) should always be required before these projects are permitted. The EIS process is where cumulative environmental impacts must be fully explored and alternative, less harmful project designs should be considered. Unfortunately, regulators don’t always require an EIS.

In October 2000, STC (under its former name, the Caribbean Conservation Corporation) and other reputable environment groups, the Environmental Defense Fund and the Natural Resources Defense Council, urged the U.S. Army Corps of Engineers to halt the large beach nourishment projects being proposed along Florida?s east coast. Each group requested that a comprehensive EIS be conducted for each dredging project and that adequate assessments be made of the cumulative impacts to nearshore marine ecosystems. STC’s goal is not to eliminate beach nourishment as an alternative to sea walls. Rather, if these projects are to be employed in the never-ending and costly battle to maintain the shifting shore, they must be carried out in the least destructive fashion possible.

David Godfrey is Executive Director of the Sea Turtle Conservancy. Based in Florida, with projects throughout the wider Caribbean, STC is the oldest marine turtle research and protection group in the world.