Flood zone maps are changing all along the U.S. coastline. And if you own a house in a low-lying coastal area, changing flood insurance rules might be throwing you a curve ball. But what if you're a builder who's in the middle of a construction project? Well, that can really get complicated.

Case in point: The situation that faced developer Jason Stone and general contractor Don Bliss in Provincetown, Massachusetts, in 2009. When FEMA released provisional flood maps for that part of Cap Cod, Stone and Bliss were in the early stages of a new development. The Orleans Cape Codder had this report in August, 2010: ("New flood zone regs make it tough for Provincetown Tides developers," by Pru Sowers).

"It's been a rough year for Jason Stone," wrote the Cape Codder. "When the Federal Emergency Management Agency (FEMA) finished re-mapping the town's flood zones last year, Stone was less than a month away from signing an agreement to sell the first of six planned luxury homes in a new housing complex located on the site of the former Tides Motel, 837 Commercial St. At $3 million, the sale would have helped pay off a construction loan Stone and his business partner had taken out to build the first houses in the complex and finance a marketing campaign to launch the waterfront complex to prospective buyers."

But the deal hung fire for more than a year, as Stone tried to contest the new floodplain designation for his property in FEMA's proposed flood maps for the area. Then, the agency told Stone that not only would his buyers need flood insurance, but Stone would have to fill six already-built basement foundations with sand, turning them into crawlspaces.

Stone found a work-around in FEMA's regulations for the foundation requirement, allowing him to install sump pumps and raise the basement floor by just 18 inches instead (at a $30,000 cost). But he says the setback was costly. "We probably lost $100,000 in carrying costs and insurance," he told the Cape Codder.