One option in Florida is to buy sand from the Bahamas and other areas in the Caribbean. Take Miami Dade as an example—they've exhausted much of their nearshore sand supply, so they're exploring getting sand from upland sources or from the Bahamas.
People Also Ask
For millions of years in the Gulf of Mexico and along the coast the constant grinding and pulverizing motion of the waves have broken down the sand. That creates a situation where the sand becomes so fine it doesn't take more than a small breeze to displace it on the beach. This is called “saltating”.
Filling a breakwater with imported sand can stop the breakwater from trapping sand from the littoral stream (the ocean running along the shore.) Otherwise the breakwater may deprive downstream beaches of sand and accelerate erosion there.