At the same time, the final bill deletes a provision contained in an earlier draft that would have forgiven the program's debt. The debt-forgiveness provision was removed earlier this week, according to several industry officials.

Currently, according to a March 2011 analysis by the Government Accountability Office, the program is running a $17.8 billion deficit.

The bill has strong bipartisan support and was drafted by the committee leadership, Sen. Tim Johnson, D-S.D., chairman of the committee, and Sen. Richard Shelby, R-Ala., ranking minority member of the Senate panel.

Johnson, Shelby and Sen. Roger Wicker, R-Miss., entered into an agreement to work on further changes to Wicker's COASTAL Act amendment as the legislation moves to the Senate floor.

The amendment would split the difference on the sensitive "wind-vs.-water" issue and create a "standardized loss-allocation" system to distribute losses between the National Flood Insurance Program and private or residual-market wind insurers following the total loss of any property that carries both flood and wind coverage.

The committee adopted amendments by Senator Mike Johanns, R-Neb., which requires the GAO to study low-participation rates of Native Americans on tribal lands, and an amendment by Sen. Jerry Moran, R-Kansas, to provide relief to communities behind levees.

It gives the Federal Emergency Management Agency (FEMA) great leeway in setting rates, especially in areas subject to mandated flood insurance through new mapping.

Another provision would require FEMA to tighten its controls over the Write-Your-Own program, which has been heavily criticized by the GAO as poorly managed.

The Johnson-Shelby bill does not add business interruption and additional living expenses to the program. Those provisions were added to the House bill during the amendment process and survived an effort by Rep. Jeff Flake, R-Ariz., to delete them during the House flood debate.

A maximum four-year phase-in of actuarial rates would be required under the Shelby bill. By contrast, the House bill is quite different, phasing in actuarial rates five years.

At the same time, the Shelby bill adds a requirement for FEMA to allow customers that do not already have their premiums escrowed every month to pay their policies in installments, "providing a more affordable option for consumers purchasing insurance." The House bill allows quarterly payments for people whose premiums are not escrowed.

Currently, FEMA requires a single, annual payment.

The Senate bill would also allow FEMA to raise rates up to 15 percent annually; the House bill limits annual increases to 10 percent.

And while the House bill calls for a strong local role in remapping, the Shelby Senate bill would leave the matter to professionals.

The Senate bill does include a provision added by amendment to the House bill that requires FEMA to set up a reserve fund aimed at ensuring that the NFIP has the ability to pay off losses during heavy flood periods.