Tens of thousands of homes across the nation have been flooded again and again. Then some of the owners repeatedly collect federal flood insurance -- often exceeding the homes' true value.

That is the conclusion of a report from the National Wildlife Federation, which wants the government to buy up more houses in flood-prone areas.

• The study documented 5,629 homes -- or almost 10 percent of the houses flooded more than once -- where cumulative flood insurance payments exceeded each building's value.

• In all, these homes were valued at $307.5 million, but their owners received $416.4 million in payments -- more than a 35 percent overrun.

• Louisiana and Texas were the states with the highest costs for repetitive loss claims .

• New Orleans and Houston topped the NWF's list of the 200 costliest areas for repeated flood claims .

Nearly 59,000 single-family homes were flooded more than once during any 10-year period between 1978 and 1995 -- with claims for at least $1,000 each time. Their owners received $2.6 billion in flood insurance payments.

In one case, a house in Houston was flooded 16 times in 18 years. Its owners received $806,591 in payments -- even though the house was only worth $114,480.

The federally-operated insurance program is supposed to break even, but is actually hundreds of millions of dollars in debt. The NWF is backing a Clinton administration request for more funds to buy up flood-risk homes, which they contend will save the government money in the long run.