>> hadn't been there in the history of pequannock. there's 229 houses in that area.any of these people go to sell their home, the buyer won't be able to get his mortgage unless he purchases flood insurance. that house just lost $100,000 in value, just from the, producing these maps. >> reporter: and none of these people know about this? >> not yet, no. >> reporter: joe golden believes the new maps go overboard, and has vowed to fight on behalf of affected homeowners. >> the maps are showing you sea level rise in the new york region. >> reporter: fact is, says climate scientist radley horton, even if pequannock wins, its victory will probably be pyrrhic. though it's away from the coast, where rising ocean levels would make it even more vulnerable, property values are at risk of plunging here; insurance, of shooting up to reflect the true economic risk. is that fair, given all the uncertainty around the science of this? >> well, it's probably not fair to the individuals. but with rising seas, more moisture in the air, we do expect to see areas that aren't currently in