BP's burgeoning oil spill in the Gulf of Mexico may hurt property owners more than any storm as sludge threatens to wreak long-term damage on the region’s most valuable asset: its environment.

“I’ve been through Hurricane Camille, Hurricane Frederick and Hurricane Katrina,” said Greg Miller, owner of Fort Morgan Realty and Development Inc. in Gulf Shores, Alabama. “They all pale in comparison to this.”

Florida Governor Charlie Crist yesterday extended a state of emergency to 13 coastal counties as far south as Sarasota. The oil, leaking at an estimated pace of 5,000 barrels a day, was flowing east toward the Alabama and Florida coasts at the time, then shifted further offshore in the afternoon, according to the National Oceanic and Atmospheric Administration. Any oil that comes ashore will hit an area where real estate values depend on access to white sandy beaches.