FEMA's Preliminary Work Maps show only 400 structures in the borough are in Flood Zone V — areas that can face waves higher than 3 feet — compared to the 1,700 structures in maps released in January after Hurricane Sandy.
The updated maps show fewer homes in high-level flood zones because they are based on more accurate data about which streets are most prone to flooding. The January maps were much more conservative in their assessment, FEMA spokesman Donald Caetano said.
“The info is a little more accurate, a little better than the advisory flood map,” Caetano said.
Before Sandy, 300 structures were in Flood Zone V in Staten Island. If the January map number have stayed, 1,400 buildings would have been added to Zone V.
The maps will be used as the base of the preliminary flood-insurance rate maps, which FEMA plans to release in mid-to-late summer.
The maps are used to calculate the rate home and business owners pay for flood insurance, and are different than the ones the city uses to determine which neighborhoods should be evacuated.
While the number of homes in Zone V has decreased from January, the majority of the city will still see a rise in their flood plain and Base Flood Elevations, FEMA officials said.
FEMA estimates that about 2 percent of New York City is susceptible to high-velocity waves, which is about twice the area in FEMA’s current flood insurance maps.
Residents can go to Region2Coastal.com and type in an address to find out what zone they’re in, or to see if their homes need to be elevated to meet new requirements.
After FEMA releases the flood insurance maps, there will be a 90-day public-comment period before they are finalized.
Typically, it takes 18 to 24 months after the public-comment period for the agency to finalize the maps, FEMA said.