The cost of federal flood insurance will likely rise for thousands of Houston-area homeowners after Congress hits its September deadline to renew and reform the deeply troubled program.

The National Flood Insurance Program was created because private insurers couldn't bear the risk of catastrophic loss, but the program is $24.6 billion in debt and struggling to remain solvent. It covers more than 300,000 homes in Harris and Galveston counties.

"The program offers rates that do not fully reflect the risk of flooding." the U.S. Government Accountability Office concluded in a report last month.

Ed Schreiber, Houston region president for Bancorp South GEM Insurance Services, which sells federal flood policies, says long-delayed changes have to come soon. "We have a product whose pricing hasn't been able to support the losses," he said.

Congress tried to fix the problem in 2012, but the program lapsed for a month amid the effort, stalling home sales in flood-prone areas. The reforms that finally passed caused some rates to soar, so they were swiftly repealed. Now, a five-year extension is set to expire this fall, demanding fresh action. No one can say exactly what measures lawmakers will take, but one thing seems probable: rates will rise, especially in flood-prone places.

Christian Rumscheidt, like many Houstonians who live in low-lying areas, knows how necessary it is to carry flood insurance.

More Information By the numbers NFIP policies in force nationwide: 5.01 million

In Texas: 606,052

In Harris County: 254,780 Total NFIP coverage nationwide: $1.2 trillion

In Texas: $163.5 billion

In Harris County: $73.3 billion Total NFIP claims paid nationwide: $56.7 billion

In Texas: $6.8 billion

In Harris County: $3.05 billion

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When water started rising on Tax Day 2016, he bolted from his front door and started swimming, nine doors down El Miranda Drive to the house he inherited from his father. There, boxes of watercolors his late grandmother had painted rested on the floor as floodwater pressed on the front door.

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He threw a brick through a window, climbed in and salvaged every painting but one. In both houses, about 18 inches of water claimed almost everything else: Furniture, carpet, new wood floors, a leaf blower and a washing machine, baseboards, insulation, Sheetrock, and even the wood inside the walls.

He avoided financial ruin because he paid $446 annually for an NFIP policy on each of his houses. After the flood, he claimed $110,000 for one and $270,000 for the other.

He pays that relatively low rate because, like 60 percent of the homes that flooded that day, Rumscheidt's houses sit outside a 100-year floodplain, the low-lying space beside waterways most prone to flooding. Rumscheidt's homes overlook Horse Pen Creek, and the floodplain ends in his back yard, within feet of his house, according to current maps.

Homes outside a floodplain can pay about $450 for full coverage, getting $250,000 for structural damage and $100,000 for contents, said Ruth Escamilla, a sales executive at Bancorp South GEM in Houston.

A Harris County homeowner living inside a 100-year floodplain without certain mitigation measures - a raised foundation, for example - can pay about $3,200 per year for flood insurance, with a $2,000 deductible, while someone living near the coast in Galveston can pay up to $8,000.

"The rates are only going to get worse as time goes on," she said. "They're taking away more of the subsidies, so that we're going to be more and more responsible for the floods."

Between 2008 and 2012, the federal program survived a series of 17 short-term Congressional renewals that left policy unchanged. Once in 2010, inaction allowed the program to lapse for 33 days. The National Association of Realtors calculated that, in turn, caused the delay or cancellation of about 1,420 home sales per day for that period. A repeat of that lapse is the biggest immediate concern for Houston.

"The inability to obtain flood insurance freezes this entire marketplace," said Ed Wolff, co-chair of governmental affairs advisory group for the Houston Association of Realtors.

In 2012, lawmakers eventually passed a five-year extension and reform with an act that phased out subsidies for some high-risk homes, which it said paid "artificially low rates." Some homeowners in Florida, in particular, saw their rates projected to rise nearly tenfold. Groups protested, and virtually all key provisions of the 2012 reform were repealed two years later.

"They've been punting this ball down the street," said Mark Hanna, spokesman for the Insurance Council of Texas. "Eventually, they've got to come up with some type of remedy."

Meanwhile, flood-related claim costs have surged. All but two of the 15 most expensive events for the flood insurance program have occurred since 2000. Hurricane Katrina in 2005 tops the list at $16.3 billion, followed by Superstorm Sandy in 2012, $8.4 billion; Hurricane Ike in 2008, $2.7 billion; and Louisiana floods of 2016, $2.1 billion.

Torrential rains that swamped Houston and other parts of Texas in 2015 and 2016 take spots 14 and 15, respectively.

There's little to suggest the rising costs of these floods will abate.

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One priority to reform flood insurance is to deal with properties that flood repeatedly.

Harris County has 9,700 "repetitive loss" properties, defined as property for which two or more flood insurance claims of more than $1,000 have been filed within 10 years.

There are another 1,965 "severe repetitive loss" properties, defined as a property that has claimed more than $5,000 dollars of flood insurance on at least four separate occasions, or has filed at least two claims that amount to more than the structure's worth.

Across the state, "a small percentage of structures are responsible for a large percentage of claims," Texas Floodplain Management Association executive director Roy Sedwick said.

Michael Bolton bought a home in Northwest Harris County's Hearthstone neighborhood in 1991. Though the house was not in the 100-year floodplain, he bought flood insurance when he noticed water creeping higher in the street with each major rain.

After his home took eight inches of water during a 2008 storm, flood insurance paid him $85,664.

In 2009, it was 18 inches and $55,055. In 2016, 25 inches and $65,000. By that third time, Bolton had reduced his coverage because of skyrocketing premiums.

Bolton's home, worth $206,000, has incurred about $205,720 worth of flood-related repair costs.

"People like me should be bought out," he said.

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FEMA has funded buyouts of more than 2,000 Harris County properties since 1985, primarily targeting homes in the 100-year floodplain, where about 105,000 remain. Bolton's house is not one of them, according to current maps.

Besides buyouts, FEMA may address repetitive loss properties by funding improvements, such as raising foundations, that reduce flood risk. In Harris County, 1,860 repetitive loss properties have undergone some sort of risk mitigation, along with more than 900 severe repetitive loss properties. FEMA spent $199 million on such improvements nationwide in 2016, a small expenditure compared with $3.1 billion in flood repair costs that year.

Spending more on risk reduction means either finding new funds or cutting expenditures on claims. But FEMA is facing an 11 percent cut in the president's 2017 budget, which proposed "eliminating the discretionary spending appropriation for the NFIP's Flood Hazard Mitigation Program" in order to"ensure that the cost of government services is not subsidized by taxpayers who do not directly benefit from those programs."

The most likely outcome of flood insurance reform will be increased privatization of the program to relieve FEMA's burden of risk.

In a letter to flood-weary constituents last week, U.S. Rep. Ted Poe, R-Kingwood, wrote that Congressional committees are beginning work on flood insurance renewal, and that "preliminary plans allow private insurers greater and easier access to the marketplace."

"To remain financially viable, the flood insurance program must be restructured," he noted.

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Virtually all reform proposals issued by industry groups call for increasing privatization of flood insurance, but that won't be cheap. The federal program was created precisely because private insurers couldn't bear the risk of catastrophic loss.

A small number of private insurers have begun offering their own insurance in recent years, mostly for extremely high-value properties.

"They're going to make to make it somewhat attractive for the industry to want to take part in this program," said Hanna of the state insurance council.

One way to do that, he said, would be to allow insurers to "charge whatever rates they felt necessary, knowing that flooding would be very likely."

SmarterSafer, a coalition of housing and insurance groups, is lobbying Congress to adopt a more "risk based" pricing system, by which homes are re-evaluated for flood risk and assessed new premium rates accordingly.

"There should be a phase in," SmarterSafer spokeswoman Jenn Fogel-Bublick said. "People should not be hit with an immediate increase that would displace them."

The group also advocated rate subsidies for low-income homeowners in high-risk areas.

FEMA acknowledged in a statement that private carriers offer a viable alternative to the federal program. Still, without a renewal of the program this year, the agency noted it would stop selling and renewing policies for millions of properties nationwide.

That must not be allowed to happen, NFIP director Roy Wright told the U.S. Senate committee on banking, housing and urban affairs on Tuesday.

"The stability of the real estate and mortgage markets depend on this," he said.