Few know about the erosion happening just to the east of the cape on St. Vincent Island.

 

 

Many local residents and visitors are familiar with the erosion problems along Cape San Blas.

Many will know about the movement of the lighthouse from Cape San Blas into Port St. Joe proper because of that erosion.

But few know about the erosion happening just to the east of the cape on St. Vincent Island.

A Florida State University professor and scientist will spend the next few years gathering data on St. Vincent Island in order to gather as much data on shoreline retreat as possible.

Jeff Chanton, the John Widmer Winchester Professor of Oceanography at FSU, has been visiting the area with his wife for 20 years.

Over those 20 years, Chanton has noticed major changes in the shoreline of the island.

“I am outside in nature a lot and I have questions,” Chanton said. “So I would like to monitor the process, it is an important thing to do.”

Chanton has been installing posts high on the shoreline and will measure the elevation of the beach against those posts multiple times each year.

He hopes to collect enough data to show what is already visually obvious, that St. Vincent Island is eroding back.

According to Chanton, the island’s sparseness and lack of human development make it a perfect place to study.

Chanton noted that almost everywhere in Florida the shoreline is protected by manmade structures and beach renourishment projects.

St. Vincent Island gives the scientist an accurate view of the process of nature without human interference.

The island is also unique among Florida barrier islands in how it was formed and shaped.

Most barrier islands are thin, but St. Vincent is nearly four-miles wide at its greatest width.

Chanton explained that this formation is due to the massive amounts of sand and silt that have flowed south out of the Apalachicola River.

Chanton believes that along with sea level rise, the impounding of sand and silt upriver has led to the island shrinking in size.

“When you put up a damn, you trap the sand and mud behind the dam and it doesn’t pass,” Chanton said.

The lack of fresh sediment then leads to a break in the cycle that once grew St. Vincent.

This isn’t the first time that Chanton has seen a similar process taking place.

Growing up in Louisiana, Chanton saw first-hand the visual shrinking of his home state due to manmade barriers.

To control the Mississippi River water levels and floods, the federal government installed miles and miles of levees in the low- lying state.

While those structures have to a great extent controlled flooding, there has been an unforeseen side effect, the massive erosion of the state’s lowlands.

Like the Apalachicola, the Mississippi moves tons of sediment southward. During floods that sediment would flow over the banks of the mighty river rejuvenating the marshland.

Now with the levees in place that sediment once used to fill in the marshes is shot out into the Gulf of Mexico.

Seeing the power of erosion up-close, Chanton became a scientist studying the effects of sea level on the environment.

“I started as a chemist, but I’ve always been interested in this kind of thing,” Chanton said.

Chanton pointed out that the map of Louisiana on the state’s road signs is actually taken from a map of the state in the 1800’s.

The professor believes his work on St. Vincent will help in some small way, and plans on continuing the study well into the future.

“Those posts will be there for a long time,” Chanton said. “If I can produce a nice data set, 10 or 15 years and there’s a record, people will be able to use everything that is still there.”