The U.S. Army Corps of Engineers plans to elevate more than 3,000 residential buildings in Miami-Dade County as the area becomes “increasingly vulnerable” to flood events due to the effects of climate change.
The Army Corps released a tentative plan to help flood-proof homes and critical infrastructure in “low-lying neighborhoods” throughout Miami-Dade County, as rising sea levels make them more vulnerable to flooding and storm damage. The proposal constitutes phase two of the larger “Back Bay” plan, which aims to protect the county’s most vulnerable areas from storm damage.
Members of the public can submit their comments on the proposal until Sept. 18, according to the Army Corps.
How many Miami-Dade homes are in the elevation plan
The first phase of the plan consisted of a $2.7 billion project that would elevate 2,100 residential buildings and flood-proof 400 other structures, including hospitals and schools.
The second phase of the project recommends elevating up to 3,230 residential buildings, including “2,800 single-family homes and 430 smaller multifamily residential buildings,” as well as floodproofing up to 175 nonresidential buildings and up to 100 “critical infrastructure facilities.” About 1,500 of those residential buildings would be raised to around 11 feet above ground, with around 640 raised an estimated 12 feet above ground.
Phase two focuses on areas including Cutler Bay, El Portal, Florida City, Hialeah, Homestead, Miami, Miami Beach, Miami Shores, Miami Springs, and North Bay Village, as well as parts of unincorporated Miami-Dade County, according to the report.
According to the report, the total project cost is estimated at $6.65 billion, of which the federal government will bear 65%, or $4.32 billion. The non-federal share of costs is estimated at $2.33 billion.
The Army Corps hopes to receive congressional authorization in 2028, with the construction window estimated to begin in 2032.
Why Miami-Dade County is so flood-prone
Miami-Dade County is home to multiple low-lying areas that are at risk of flooding due to a number of reasons, including heavy rain, storm surge and king tides, according to the report, threats that “frequently disrupt lifeline services.”
“The region’s extensive network of drainage canals provides direct pathways for tidal backflow and storm surge from Biscayne Bay to penetrate deep inland,” reads the draft report on the project’s second phase. “This risk is severely compounded by rising sea levels, which elevate the porous shallow groundwater table, reducing stormwater storage capacity and causing localized groundwater flooding.”
Additionally, “recent regional tide gauge data from Virginia Key” confirms that local sea levels “are rising at an accelerated rate,” which amplifies the “severity of future coastal storm risk.”
Sarah Perkel is a South Florida Connect Reporter for the USA TODAY Network’s Florida Connect team. You can get all of Florida’s best content directly in your inbox each weekday day by signing up for the free newsletter, Florida TODAY.