They call it "beach nourishment" – but the term is deceiving. What these periodical hundred million dollar projects are doing to Florida's central west coast is undermining a very thin shield of sand that has always protected its barrier islands. If we continue to assault these beaches, nature may eat those islands sooner than we think.
There are 80 miles of west Florida coastline that run from Anclote Key, just north of Pinellas, to Venice Inlet in southern Sarasota County. The 18 barrier islands that protect this short strip of coastline have always moved around adjusting to nature's way.
But the shoreline of both the islands and the inland no longer resemble nature's way of shifting sands and its redistribution of sediment, which is needed to protect shores from high sea levels; nor do they have the dunes that once protected the coast from large storms.
So when a storm takes a big bite out of a beach redesigned for recreation, the replacement of that bite only enhances the possibility of further radical shoreline erosion.
Sand pumped from a mile offshore is how all three counties within the 80 mile span retrieve the needed sand to widen their beaches.
But the barrier island chain is centered on a broad sloping carbonate platform, underlined with limestone and bedrock, and its protective sands are of limited thickness.
This island and inlet system is among the most varied in the world with its combination of low wave energy and micro-tidal conditions that produce a wide range of barrier and inlet morphologies.
In 1992, Congress directed the U.S. Geological Survey (USGS) to initiate a 5-year study of this region in order to better understand this barrier island system. This was done in response to a same year report from the Florida Department of Natural Resources that designated 65 percent of west Florida beaches as "critical erosion areas."
Analysis of core samples and seismic data indicate that, in some areas along the coast, the underlying limestone bedrock exerts significant control over the location of the barrier islands.
These islands and inlets show active geological history that dates back 4,600 years to the south, and as early as decades ago to the north; with no evidence of island migration shifting landward over the thousands of years.
Manmade maneuvering of shoreline design is flirting with disaster, should a large hurricane spend any time atop this region. What sand has been removed from one place, and placed elsewhere could magnify inland damage beyond any current estimations.
The redistribution of sand to gain beach acreage and protect structures built in proximity to coastal waters, will only exacerbate the degree of damage should a powerful hurricane strike.
Underestimating the effects from removing millions of tons of sand, from what is a limited source, with lives and property at stake, is reckless and irresponsible; yet all three local governments continue to approve development in high-hazard coastal areas.
If we continue to ignore the lessons nature has clearly displayed for wider beaches and tourist dollars, our actions could invite a catastrophe to the sun coast.
It was the dredging for Mississippi River Gulf Outlet (MRGO) that allowed the high gulf tides from hurricane Katrina to come inland, flooding New Orleans with water 12 feet above flood lines. Much of west-central Florida is only a few feet above New Orleans.
It is not a matter of if, but when. If our local leaders don't have the knowledge or the will to protect the property and people, they need to get out of the way.
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