FOR IMMEDIATE RELEASE

Contact: Tina Haisman, ASBPA Media Relations, 239-292-2882 or media@asbpa.org
Bob Dean, Sc.D., University of Florida, (352) 392-1436 ext. 1430 or dean@coastal.ufl.edu

Inlets: Good for navigation, bad for beaches
Coastal experts say inlets are necessary for our nation’s navigation and water quality,
even though they sometimes interrupt the natural flow of sand along the shoreline. Learn more about what an inlet is and what scientists and engineers are doing to restore the flow of sand.

FORT MYERS, FL – An inlet is an area where water flows in and out of a cut in the shoreline, often though a barrier island. They can be natural or manmade. The main purpose of an inlet is for navigation – both recreational and commercial – and to improve water quality. Another valuable characteristic of an inlet is that it often leads to a harbor of refuge. Boaters can duck inside an inlet to get out open waters during a storm.

Inlets sometimes have jetties built on one or both sides to keep the navigation channel in place. Otherwise, shifting sands would mean the channel would migrate along the shoreline, making boating more hazardous. A jetty is a large structure that extends out into the water with a dual function of keeping the inlet in one place and preventing sand from entering the inlet. They are usually built with large rocks.

Rather than jetties, some less developed inlets have a terminal groin on one side of the inlet, designed to help reduce erosion from the beach instead of actually maintaining the channel position.

While inlets serve their purposes well, they often interrupt the flow of sand along the shoreline. For example, on Florida’s east coast (where sand moves from north to south) many inlets block the sand flow and starve the beach on the south side of the inlet.

The problems with starving one side of the inlet are the typical challenges faced on eroding beaches: decreased storm protection, a smaller wildlife habitat and decreased recreational value.

“My students and I have conducted a lot of research and found that about 80 percent of the non-storm induced erosion on Florida’s East Coast is due to inlets,” says Bob Dean, Sc.D., graduate research professor emeritus at the University of Florida.

Florida has approximately 56 navigable inlets, compared to Texas (which has eight) and North Carolina (which has 19).

“At this point, the state of Florida is very careful not to allow new inlets to be excavated,” Dean said. “The inlets that exist now are between 50 and 100 years old – if we would have known back then what we know now, you probably wouldn’t have been able to build a new inlet without some sort of a commitment to replenish the sand loss on the starved side of the inlet.”

Dean, who is recognized as one of our nation’s pioneers in a coastal engineering, says this problem is very well recognized in the U.S., and that several states now have laws in place to try to minimize the problem.

He helped write Florida’s version of the law, which mandates improved management of the state's coastal inlets in order to reinstate or replicate the natural flow of sand along the shore.
The law dictates that all beach-quality sand disrupted by inlets must be placed onto adjacent eroding beaches. It requires that the state Department of Environmental Protection take reasonable actions to protect the state's beaches by implementing inlet sand bypassing technologies to move the sand around the inlets and by utilizing the sand dredged from the inlets on adjacent beaches. These techniques will potentially reduce the need for extensive beach renourishment and increase the length of time between renourishment projects.
For more information about inlets and beaches, please visit www.asbpa.org.

# # #

ABOUT ASBPA: Founded in 1926, the ASBPA promotes the integration of science, policies and actions that maintain, protect and enhance the coasts of America. For more information on ASBPA, go to www.asbpa.org, facebook or www.twitter.com/asbpa.