OP-ED: An Islander’s Dilemma

EDITOR’S NOTE: The following is provided to the Santiva Chronicle by Sanibel resident Sandy Winans. The Santiva Chronicle publishes opinions from local citizens who are addressing topics that are important to Sanibel and Captiva. They may be submitted via e-mail at news@santivachronicle.com.

In the aftermath of Hurricane Milton, I am wondering whether ‘Weather Central” has it in for Sanibel and her coastal neighbors. Are the long stretches between consequential storms getting shorter? A whole 13 years passed after Hurricane Charley blew through before Irma thrashed her way up Florida’s west coast in 2017. Just five years later, Ian punished Sanibel with his ‘dirty side’ winds and 8-10’ surge, and two months ago, Helene and Milton landed successive blows on the islands just as they’d begun to show new life.

I moved to Sanibel in 2021 after 40 years of vacation visits…a familiar story. My spouse and I chose a ground-level “Michigan” home in Gulf Pines as our new full-time residence, one of only three not elevated. Our community is an eco-friendly interior wetland of 100+ homes begun in 1973, purposely designed with native species and gravel/shell roads to invite the gamut of flora and fauna right into our midst. Bobcats, coyotes routinely saunter through, resident gators catch rays at the edge of our lagoons, and great flights of shorebirds often mistake us for Ding Darling and convene in our waters.

But, for Gulf Pines, already at the lowest elevation on the island, recent storms are exacting a toll. Flooding is more severe, high water lasts longer and for all of us islanders, it’s more frequent. It’s become an ongoing conversation. In our case, Ian brought 58 inches of sea water and left behind a sodden, total loss, except for concrete block and slab.

Reactions to this frequency of nasty storms have run the gamut, some feeling emotionally drained and worn out, others just trying hard to sort it out logically. So, what is going on? And what, if anything, can we on Sanibel do about it?

At one level, the answer is obvious — elevate (which we are doing). At another level, answers are elusive. A world of factors is in play, affecting when, where and how much, that identifying our options as a city, and individually as residents, takes time and patience. Adaptation proceeds no faster than understanding, and our island population has begun to realize an important distinction in flood types — those that result from rain, and those produced by a storm surge.

Two elongated basins (usually referred to as the Sanibel ‘slough’ or ‘river’), dredged in the 1950s (an East and a West, each 3 and 5 miles in length), allow the city a modest degree of flood water management over perhaps 75 percent of the island’s total area. Two weirs, installed at Tarpon Bay and at Beach Road in conjunction with the twin basins, enable the city to retain fresh water helpful for habitat and replenishing aquifers and rapidly dump excess storm water during severe flood events. In 1994, the City modernized the weirs, replacing the old wooden slats with longer hydraulically-controlled spillways. While larger and capable of faster releases, the island’s 4.5 foot average elevation remains the limiting factor in how much flood control is actually possible.

The slough and weir system, designed primarily to manage flooding from rainstorms, has little to no chance of dealing with massive inflows from storm surge. And furthermore, the system has slowly been losing its grip in the face of sea level rise (~8” since 1965) and more violent storms, generated by a warming Gulf.

Successive drenching rains, much like what occurred prior to Helene, saturate the land, leaving no place for more rain or worse, a salty surge over the dunes. The 51 inches of rain thus far in 2024 is double 2023’s rainfall. Hence, with flood management as its top priority, the City’s Public Works Department began rapid releases of interior water three days prior to Helene, and later, Milton, to create room for waters from the advancing storms.

What is not widely understood despite diligent effort by the City, SCCF, and others to educate, are the inevitable limitations levied by the island’s 4.5 foot average elevation. Colloquially, there’s only so much you can do digging retention basins, or pre-releasing interior fresh water in the face of a massive storm surge. The island is not getting higher; it’s getting lower.

More on this topic in the near future…

Sandy Winans retired in 2019 and lives full time on Sanibel after visiting for 45 years. He and his wife, Sandra, bought a ground-level home in Gulf Pines in late 2020. He spent his career with high tech companies focused largely on earth resources and conservation. He received his M.S. in environmental science from Cornell in 1980.