Experts lack data to link injuries to recent projects
By Maddy Lauria | Nov 21, 2014
During a public workshop in Rehoboth Beach Nov. 1, Dewey Beach resident and coastal property owner Clinton Bunting said future projects should support recreational beach use and not focus only on protecting property.
“Beach replenishment and nourishment … we have to have it. We have to have great bays and great beaches,” the former lifeguard said. “In the last years with the beach nourishment and replenishment, injuries have increased dramatically.”
Bunting's concerns were raised during a review of regulations that are unrelated to beach replenishment projects, Department of Natural Resources and Environmental Control officials said. His concerns will be shared with DNREC's federal partner in replenishment projects – the Army Corps of Engineers, they said.
Stephen Rochette, spokesman for the Army Corps of Engineers Philadelphia District, said the corps has not seen a correlation between completed projects and an increase in injuries, but he said there are many variables that make that connection difficult to determine.
“Beaches are dynamic and changing whether we conduct a beachfill or not,” he said.
Delaware Surf Zone Injury study
*Source: Dr. Paul Cowan, Beebe Healthcare |
Beebe Healthcare Department of Emergency Medicine Dr. Paul Cowan, who began compiling surf injury data in 2009 after he noticed clusters of beach-related injuries, said there is no comparison data available to measure current injuries against the number and extent of injuries that occurred before major replenishment projects.
No data was available on surf injuries until he initiated the Delaware Surf Zone Injury study in 2009 with Wendy Carey, a coastal hazards specialist with the University of Delaware, and DNREC representatives. The only documentation previously collected was the type of injury, not the manner in which it occurred. A dislocated shoulder was documented as a dislocated shoulder, he said; the cause could be a rough rugby bout or a rough day in the surf.
“For us to say beach renourishment itself is a causative factor, we'd have to have pre-nourishment data,” he said.
A 50-year beach replenishment plan at Fenwick Island, Bethany Beach, South Bethany Beach, Dewey Beach, Rehoboth Beach, Lewes Beach and the Indian River Inlet began nearly a decade ago. Since then, millions of dollars have been spent on projects at those sites, with millions of cubic yards of sand dredged offshore and pumped on the beach to replenish those beaches. Funding from the federal Disaster Relief Appropriations Act of 2013, following Hurricane Sandy, provided an additional $19 million for the most recent projects along the Atlantic coast beaches.
Tony Pratt, administrator of DNREC's Division of Shoreline and Waterway Management, said an offshore borrow site used in 2005 made a hazardous beach face because of gravelly material dumped onto local beaches. He said future projects will not use that borrow site.
“We're looking for sand which is going to [produce] that more shallow beach slope,” he said. He added that the Army Corps of Engineers is cognizant of the concerns raised by Bunting and the risks of using gravelly material on Delaware's beaches.
Pratt also referred to Cowan's study of surf zone injuries as a possible source of data linking the replenishment projects to increased injuries. Pratt added that the University of Delaware also was hired to study the coast on a number of fronts, including the slope of the beach and whether replenishment projects have contributed to a steeper beach.
Cowan said the study is not expected to prove or disprove any increase in injuries is linked to beach replenishment. The study will identify environmental conditions that are hazardous for beach-goers, so people can avoid surf-related injuries in the future.
“This study really in no way addresses the questions of the pros and cons of beach renourishment,” Cowan said. “What I'd love to be able to do is figure out what combination of environmental variables are occurring on the days with more injuries, so we can predict and prevent more injuries.”
The Delaware Surf Zone Injury study has found injuries occur in clusters; the study compares days with no injuries with days with six to 20 injuries to identify factors that may cause the differences. About 20 environmental variables such as wave height, wave direction, water temperature and air temperature are measured and documented along with the types of injuries, place of injury and demographics of the injured people. Cowan said the study also recently began tracking how many people are in the water on a given day to see if that plays a role on days with increased injuries.
So far, the study has concluded that most injuries occur as people, usually over the age of 30, are leaving the surf and their backs are turned toward the waves, he said.
Since 2009, the study has documented about 400 days of data, Cowan said, noting researchers are limited to summer months when people are using the beach. With a few summer seasons now documented, researchers can start to derive statistically valid comments, he said.
“The longer we can continue to collect data, the more statistically valid it will be,” he said. “The most important thing for us at the end of the day is that this is about public awareness and injury prevention.”
Cowan said he hopes to share some findings based on the data within the next year or two, but he reiterated that the study was not designed to look at whether injuries have increased as a result of beach replenishment.
Pratt said science is needed to reach the conclusion that replenishment projects are having any effects on surf-related injuries.
He said DNREC and the Corps are looking for fine sand that is more compatible with recreational use.
The corps is responsible for renourishment projects along the ocean front, but the state takes the lead on these projects along the Delaware Bay. Oceanfront projects, while designed and executed by the corps, are 65 percent federally funded, with the state paying the remaining 35 percent. Borrow sites and sand placement projects are monitored through subaqueous lands permits through DNREC, said DNREC Environmental Program Manager Michael Powell.
“We worked collaboratively with the corps to the extent they needed our help,” Powell said. He said the Beach Preservation Act of 1972 was written at a time when current beach replenishment strategies didn't exist. Large-scale dredge projects and massive sand dumps were not standard practice when the act was passed, he said.
Rochette agreed that the corps does its best to find sand that is similar to the native material found at replenishment sites. Still, he said, reducing storm damage is really the corps' primary concern.
“We are required to select the plan to maximize the storm damage reduction benefits relative to the total cost of constructing a project,” he said. He added that projects take into account environmental impacts and technical feasibility.
DNREC is the nonfederal sponsor of the ocean-front projects and in turn works closely with municipalities in project areas, he said.
Rochette added that years of study, design and build stages, including public input precede dredging projects. The Corps tries to match the grain size of the fill to the native material as closely as possible and design projects based on the existing slopes in the area.
“We also know that coastal processes rework the profile into a more natural equilibrium state after a period of time, usually several months after construction,” he said. “It's important to remember that we are there in full partnership with the state of Delaware.”