The unprecedented scope of the natural disasters that hit the Gulf Coast in Hurricanes Katrina and Rita will lead to an equally unprecedented flood of dollars designed to help the region rebuild.

Along with that comes the responsibility of making sure those dollars are spent wisely.

That's the issue facing members of Congress and oversight officials within the agencies most directly involved, including the Department of Homeland Security.

More auditors and specialists have been brought on board, but clearly there's a need for a smart, coordinated oversight plan.

Critics who fear this relief effort will become a funnel for extravagant waste and improper spending already have their poster child.

The Federal Emergency Management Agency has contracted with Carnival Cruise Lines for three ships to be stationed off the Gulf as emergency housing. The deal — designed ostensibly to offset the losses the line will experience by pulling the ships out of commercial service — works out to $1,275 per evacuee per week.

But as Sens. Tom Coburn of Oklahoma and Barack Obama of Illinois point out, this is far in excess of the $599 tab per person for a weeklong cruise out of Galveston. Officials who made the deal said it was the best they could have done, given the circumstances.

That's pitiful. And it underscores the need for tough oversight over what is being perceived by some as a government-funded gravy train.

Obama and Coburn are offering a sensible start. They want a chief financial officer to oversee all Katrina (and related) relief spending.

Another encouraging sign: the Inspector General's office of the Department of Homeland Security has set up beefed-up office dedicated solely to oversight of hurricane relief spending. With more than $60 billion already appropriated and with the overall relief effort expected to top $200 million, the potential for abuse is staggering. The time for tough oversight is now.

Congress should set up its own umbrella oversight agency, perhaps through the General Accounting Office, to keep a close eye on spending. The risk of wasting precious relief and rebuilding dollars is one we can't afford to take.