Biscayne Bay

Barrier islands like Key Biscayne — vulnerable to sea level rise and tropical storms — are in the eye of the property insurance crisis, with owners seeing huge premium hikes and policy cancelations.

Miami-Dade County's latest plan to protect against stronger storms and rising sea levels involves closing off most of Biscayne Bay from the Atlantic Ocean with natural and man-made barriers.

The study, the first authorized to look at the system since the Everglades restoration plan more than two decades ago, will deal with sea rise.

A large, slow-moving Category 4 storm like Hurricane Ian would push a catastrophic surge across much of coastal Miami-Dade many times worse — and extending much farther inland — than Irma did in 2017.

The Corps said it's willing to spend another $8.2 million and take up to five years to better coordinate other plans covering drainage, Biscayne Bay and Everglades marsh restoration and beach renourishment.

The 4-year study by the U.S. Army Corps of Engineers found storm surge flooding alone could amount to $24 billion annually with three feet of sea rise, thanks to a warming planet.

The 156 oysters were sampled from Biscayne Bay — which showed the highest number — along with Tampa Bay and Marco Island.

The money will be used for restoration projects that have dragged on for years, including building a reservoir and undoing damage from old bridges built in the Everglades.

So far, 250 dead fish have been confirmed in the Tuttle Basin at the bay's north end, where poor circulation means water gets flushed less often.

The Corps and Miami-Dade would have shared the $4.6 billion cost for the work that included fortress-like flood walls and gates. How much the Corps pays will now depend on the plan the county proposes.

A new study by the University of Miami and National Oceanic and Atmospheric Administration that tracked sawfish in Biscayne Bay for the first time found sightings increasing, suggesting the bay may provide an important migratory route or other important habitat.

Conservation groups plan to sue Florida Power & Light after the discovery of a radioactive isotope in Biscayne Bay linked to a nuclear power plant...