comment: history of Longboat Key and Cancun beaches/sandbags/

From: Jerry Murphy
Ray Eifler posted a very interesting story about the early use of sandbags to protect the beaches at Cancun. That sparked my interest and I looked into what has subsequently happened there…it’s not a pretty story but it should inform our considerations re our beach and demonstrate what can go wrong.     
In ’05 Wilma destroyed the beach all the way up to the beachfront hotel foundations. Sometime in ’06 the Mexican government (aka taxpayers) spent $19milUS on a heavy duty renourishment ‘a la what is being proposed for PL. In ’07 Hurricane Dean took all that out. In ’09-’10 the taxpayers paid for another round of heavy duty repair costing $70milUS. The technology in both cases is the same used on Longboat Key several years ago that I observed two iterations of, in only 18 months: offshore dredging, onshore bulldozing, and installation of groins.
To end this story, three things to add: 1.) the latest repair at Cancun has allowed a high escarpment or shelf of sand to form on the beach landward of the water, that in places is higher than 5 feet. That makes it impossible for most people to get to the beach in such places and requires the frequent use of bulldozers, an on-going heavy maintenance expense. 2.) those escarpments also  formed on the Longboat Key beach and though far lower, made entry to the water difficult and even dangerous for children and the elderly. 3.) at Cancun there has not been more ultra heavy weather since the last repair. But even then, sand is being lost…up to 8 percent at recent tally.
For those interested there is a lot of video on YouTube that shows repair in progress and the escarpments that are an ongoing problem.