Most American drivers know they can’t drive any purchased vehicle off the lot without car insurance. Many home buyers at real estate closings can relate when it comes to flood insurance.

So it seems unfair that, with millions of Americans dependent on federally guaranteed flood insurance to buy their homes, Congress has allowed the National Flood Insurance Program to expire time and time again.

We believe American homeowners deserve better, and that’s why we’re supporting a bipartisan bill to extend the NFIP for five years and place it on a more sustainable financial footing.

This isn’t a controversial approach. In fact, such a long-term extension already passed the House last July by a 406-22 vote, and the Senate Banking Committee passed a similar measure in September that is currently awaiting a vote on the floor. More than 40 Senators are already on record in support of moving flood insurance legislation to the floor.

In addition, these bills have the support of a wide spectrum of environmental organizations, business associations and taxpayer and homeowner advocacy groups. This is an issue that cuts across party lines because it literally hits home for so many Americans.

The NFIP was last fully reauthorized in 2004. Since that reauthorization expired, the program has been kept alive by 13 short-term extensions — some as short as 30 days.

The program is intended to serve as a lifeline for approximately 5.6 million homeowners and commercial property owners, many of whom live in high-risk areas where no other flood insurance is available. But too often it’s been used as a political football in various policy fights, with Congressional leaders running out the clock and delaying action on the NFIP until the last minute.

In 2010, the program expired four times for a total of 53 days, adding uncertainty to an already fragile housing market and delaying or cancelling more than 1,400 home closings each day the program was expired. The lagging housing market is clearly hurting our economic recovery, and Congress should be doing everything it can to help the housing market recover. Extending the NFIP is certainly part of that equation.

In addition to creating instability in the housing market, Congress’ inability to pass a long-term extension has kept us from making some much-needed changes that would protect taxpayers and ensure the NFIP’s solvency for years to come.

The program is currently in an $18 billion hole, mostly because of claims paid out after major hurricanes, including Katrina and Rita, caused damage on an unprecedented scale. The House and Senate bills would take steps to address that shortfall, including a gradual increase in premiums on certain high-risk properties.

We’re working together to ensure that whatever the final bill looks like, it does two specific things. The bill should return the Army Corps of Engineers to its traditional role in levee certification, and, consistent with warnings from the Government Accountability Office, it must not increase premiums so sharply that homeowners are discouraged from purchasing flood insurance. The goal is to make the NFIP as sound as possible, for as many folks as possible, for as long as possible.

But once more, the clock is ticking. The current extension of the NFIP is scheduled to expire on May 31, and it doesn’t make sense to punt on this issue yet again.

Joining with 39 of our colleagues, we sent a letter to Senate Majority Leader Harry Reid (D-Nev.) and Senate Minority Leader Mitch McConnell (R-Ky.) urging them to bring the Senate bill up for debate and passage soon. We hope they’ll agree with the bipartisan group of Senators who signed our letter that this is a clear-cut issue with exactly the kind of bipartisan consensus that Americans want to see in Washington, D.C.

Congress’ inaction on this issue has created too much unneeded uncertainty. With more than five million American property owners forced to wonder whether their homes and businesses will be insured past May, the time to act is now.

Sen. David Vitter is a Republican from Louisiana. Sen. Jon Tester is a Democrat from Montana. Both are members of the Banking, Housing and Urban Affairs Committee.