THE WOODLANDS, Tex. — Leslie Martinez heard the floodwaters before she saw them. They rushed across the lawn, seeped around the doors and into the house. It was 2:15 a.m. on Aug. 28, three days after Hurricane Harvey made landfall. Her young daughter was asleep in her arms. Ms. Martinez’s first reaction was to spread towels around the floor.
After all, Ms. Martinez recalled, the home builder had assured her that “flooding was not even a possibility” when she and her husband purchased the house in this suburban enclave north of Houston in 2011. They would never have bought here otherwise. Flood insurance, of course, was neither required nor needed.
Now, with the rains outside lashing and the water inside rising, the family and their terrified pet, a one-eyed goldendoodle named Coco, took refuge on the second floor. Later that day, rescue boats came and ferried them to safety.
The flooding forced Ms. Martinez and her husband, John Ahearn, to borrow money from their parents and accept a donation from their daughter’s school. It left them feeling furious and betrayed. “I’m scared that it’s going to continue happening,” Ms. Martinez said, even as she wondered how they had become the victims of something they had been told had a vanishingly small chance of coming to pass in such a short time since the purchase.
What they did not know was that their home, and those of many of their flooded-out neighbors in this new section of The Woodlands, had been built on land that not long ago lay squarely, and sometimes soggily, in a flood plain.
A New York Times examination found that in the years leading up to Hurricane Harvey, with a surging local economy fueling demand for new upscale housing, the developers of The Woodlands had used a wrinkle in the federal flood-mapping system — along with many dump trucks’ worth of dirt — to lift dozens of lots out of the area officially deemed prone to flooding. What they had done, in effect, was create gerrymandered maps of risk.
In Ms. Martinez’s case, documents show, the land was raised less than 10 inches above the level that, under federal flood-insurance rules, would have required the family to be notified of their risk and purchase insurance. Other lots in their area were raised as little as 1.2 inches above that height.
No one has suggested that the developers broke any laws, and the company that owns The Woodlands says it followed all applicable regulations and standards. But the experiences of the family of Ms. Martinez and their neighbors show that even when the mapping rules are followed to the letter, the results can be disastrous.
The adjustment process began as a way to correct the wild inaccuracies in the maps that form the basis of the federal flood-insurance program, which was created in the 1960s to protect homeowners from catastrophic loss. Increasingly, though, the changes have also become a way for developers to build on low-lying land.
Across the country, documents show, the Federal Emergency Management Agency, which runs the insurance program, has granted more than 150,000 map changes in the last five years. In some cases, lots were raised, and in others, levees, drainage systems, water-detention ponds and other methods changed the calculated flood risk for a swath of land.
Many of these changes were unquestionably appropriate. But in the Houston area, a Times analysis of FEMA documents shows, at least 6,000 properties in redesignated zones were damaged during the flooding caused by Harvey.
“This is all about engineers doing things for developers rather than for the public,” said James B. Blackburn, co-director of the Severe Storm Prediction, Education and Evacuation from Disasters Center at Rice University in Houston. Mr. Blackburn, who was involved in early designs of The Woodlands, added, “It would be nice to know that you were only two inches above the flood plain. You know, that’s not a lot of margin for error on these maps. Yet all the federal protection for flood insurance gets removed.”
What happened in The Woodlands underscored one of the great lessons of Harvey’s assault on Houston: the profound vulnerability of a metropolis with an ethos of untrammeled development built, essentially, on a swamp.
To Ms. Martinez and her neighbors, the cruel twist was that it could happen here — in a community founded in 1974 as a kind of anti-suburbia by an oil and gas billionaire named George P. Mitchell. If The Woodlands was a community apart, rich with woods, lakes, trails and streams, Mr. Mitchell was its benevolent dictator, whose vision of building quality and environmental balance fostered a reputation of a development where the flood risk was extremely low.
Mr. Mitchell sold his company’s stake in The Woodlands Development Company in 1997, and the community has been steered by a succession of publicly traded companies — most recently, the Howard Hughes Corporation, which bought a major stake in 2010 and acquired the rest the next year.
Don Hickey, a 37-year resident of The Woodlands who was an early employee of Mr. Mitchell, said people paid more to live here in part because they felt they would be safe. Mr. Hickey, who works in real estate finance and is collaborating with fellow homeowners to get their flooding problems fixed, summarized the situation in caustic terms, saying, “The developer had an economic benefit to more aggressively develop land around the flood plain or spend less money on flood control.”
The company says there has been no slippage of quality through the transition of ownership.
“Since development began at The Woodlands more than four decades ago, it has strived to be a model master-planned community. While ownership has changed, what has never changed — nor will ever change — is our strict adherence to standards and our commitment to our communities,” said Grant Herlitz, president of the Howard Hughes Corporation.
Hurricane Harvey, the company argues, was an exceptional flooding event, and all map revisions followed federal and local guidelines. “To the extent that standards are re-evaluated, we will do as we have always done and act in accordance with any new regulations,” Mr. Herlitz said.
The National Flood Insurance Program and the flood maps used to establish the need for insurance have been a constant source of controversy. Critics of the program argue that it often ends up repeatedly paying for damaged properties instead of pressing for mitigation of flood risks and relocation, and thus ends up encouraging people to build — and rebuild — in risky places.
The risk is defined by law, not nature: FEMA and the flood insurance program look to what is known as 100-year flood elevation to determine who needs to buy insurance. Anything lower than that is considered to be in the flood plain. Above that level, supposedly, is safety.
But how safe? The 100-year flood level does not mean a flood will happen only once every 100 years. Instead, it refers to a 1 percent chance of flooding in any given year. (A 500-year flood, which reaches somewhat higher elevation, is one with a .2 percent chance of occurring in a year.) That 1 percent chance actually translates into a one-in-four chance of a flood occurring at least once during the life of a 30-year mortgage. And in Houston, as in many parts of the country, 100-year floods are distressingly common. The Houston area saw three such events in the past three years. Climate change threatens to make them even more likely.
To Mr. Blackburn, the 100-year line is too arbitrary for comfort. What’s more, the flood maps have long been considered highly inaccurate.
This led to a lot of unhappiness among homeowners forced to pay perhaps $5,000 annually for insurance that would cost less than a tenth of that outside the official flood plain.
“People started to come in and argue and said, ‘You showed me in a flood plain and I’m 40 feet above that level.’ Because FEMA’s topography was so inaccurate,” said Larry A. Larson, director emeritus of the Association of State Floodplain Managers in Madison, Wis.
By the 1980s, he said, the agency, too overwhelmed and underfinanced to make all the corrections itself, instituted new procedures for accepting revised elevation data from engineers hired by aggrieved citizens.
Developers have taken advantage of the new system as well, FEMA documents show, with a range of techniques from hiring surveyors to correct elevations to building structures like levees and drainage channels. In one of the most common methods, developers truck in tons of soil — known as “fill” in the building trade — and dump it over wide areas to raise the elevation above the flood plain. Mr. Larson called changes that lifted the ground only slightly above the flood plain “a bad idea” because such areas generally remain prone to flooding.
“Once a flood plain, always a flood plain,” he said. “It’s still got risk.”
His observation was borne out in striking fashion in the neighborhoods covered by the two map revisions examined by The Times: Eighty of the 81 homes within those areas near Spring Creek — which flows through The Woodlands — sustained some degree of flooding, according to FEMA statistics.
Harris County, home to large parts of suburban Houston, including the newer sections of The Woodlands, is one of a handful of districts around the nation that FEMA has granted a sort of shared authority in approving map revisions. Although the conditions of this authority are complex, and vary from district to district, others have used it to enforce standards that are more stringent — for example, generally requiring higher elevations for any change and pushing developments further from creeks than FEMA does.
For its part, Harris County has stuck with FEMA’s elevation standards. “We don’t want to touch the FEMA process; we want to keep it intact,” said Ataul Hannan, planning division director for the Harris County Flood Control District.
What the county has done is put a great deal of effort, and expense, into creating special software model for more accurately calculating flooding risks and the wider effects of development in the relatively flat terrain of the Houston area, Mr. Hannan said. Comparing Harris County’s regulations to those in other parts of the country is unfair, he added, because the topographies are so different.
In the business of flood-map revision, the pressure usually runs one way. There is seldom much local interest in having a neighborhood declared flood prone, said Sarah Pralle, an associate professor of political science at Syracuse University who studies the politics of flood insurance and has written about lobbying efforts by New York and New Orleans to alter the maps.
“The shrinkage of the flood maps,” she said, “is always treated in a very positive way.”
As early as 2006, The Woodlands filed a plan for a new subdivision on thousands of acres containing “wooded areas and a few rural home sites,” according to documents obtained from Harris County. But it was not until the years leading up to 2011, when the Hughes Corporation put together the final pieces of its purchase of The Woodlands, that the housing market caught up with the plan. Houston shook off the wreckage of the subprime mortgage crisis and encountered a very different problem: a shortage of housing on the high end of the market.
Touching off the surge in demand was an announcement by Exxon that it was opening a new corporate campus in nearby Spring. Exxon was far from alone, as a growing list of companies relocated to the area. So did tens of thousands of workers, drawn by the boom in fracking technologies that none other than Mr. Mitchell and colleagues had coaxed, tweaked and perfected over nearly 20 years.
That influx would have all but saturated the existing home market, said Bill Gilmer, director of the Institute for Regional Forecasting at the University of Houston. It drove a spike in land prices, allowing developers to consider new construction on relatively low-cost lots that previously would have been too costly to improve.
“This would just give you the opportunity to make those extensive improvements and still come out ahead,” Mr. Gilmer said.
FEMA maps of The Woodlands showed a tantalizing stretch of undeveloped land hard by a waterway called Spring Creek — including acreage in the 2006 plan. Building right along the creek would have been out of the question, but farther south, portions of the land were slightly above the 100-year flood plain, according to the maps. Those who knew the land and its history saw warning signs. Nick Rife, whose family owned land in the area, said he used to hunt there “when it wasn’t flooded.”
By bringing in thousands of dump truck loads of dirt, it would be possible to expand the acreage above the flood plain, making the whole area suitable for construction. That is exactly what The Woodlands decided to do, documents show.
The former edges of the flood plain run through what are now the lots of Ms. Martinez and Mr. Hickey, the longtime Woodlands resident who once worked for Mr. Mitchell and had built a new home in the neighborhood. On the strip of land containing Wood Drake Place — Ms. Martinez’s street — 60,907 cubic yards of dirt were laid down. FEMA approved a map change for that area on Feb. 8, 2011, documents show. The large extrusion of development around Lake Reverie Place — Mr. Hickey’s street — and the nearby Sundown Ridge Place got 19,890 cubic yards of dirt. On June 13, 2013, FEMA approved a map change for what would become lots for the 81 homes in those areas.
The result: neighborhoods that seemed safe from flooding. When Esteban and Paola Seañez moved into their home next to Spring Creek in 2015, their mortgage company assured them that the plot was high and dry. When the couple asked about flood insurance, “They said, ‘You don’t even have to purchase it,’” Ms. Seañez recalled.
Last year, after water came within several feet of their door, Mr. Hickey’s neighbors James and Gayle Soeder inquired about flood insurance. Initially, the agent warned that the policy would be very expensive; the house was in a flood plain, she said. Mr. Soeder, who knew he had bought a home at the 500-year elevation, asked her to check again. “We see that the flood plain was revised recently,” the agent said. So, for a bargain rate of $450 per year, the Soeders became one of the families in the neighborhood to be covered by insurance when Harvey struck.
A number of residents asked whether managers of The Woodlands since Mr. Mitchell had been as careful as its predecessors in designing the newer developments, and pointed to what they called more aggressive policies since the Howard Hughes Corporation — a brand revived in 2010 by the activist investor Bill Ackman — took over.
Mr. Hickey dug into damage statistics and found that his recently constructed neighborhood flooded at far higher rates than others in The Woodlands. In older parts of the community, his research revealed, about 215 out of 33,000 homes flooded during Harvey, or less than 1 percent — a far smaller percentage than many other communities in the greater Houston area. Yet among homes built in more recent years in Harris County, 331 out of 4,993 flooded, or more than 6 percent.
In the newest areas of that Harris County expansion, including those where the Soeder, the Hickey and the Seañez families live, 331 out of 1,450 homes were affected — a whopping 23 percent. Mr. Hickey questioned whether adequate measures had been taken in the fill project to provide water storage and drainage in big storms. Marc Crudgington, who bought his home the year after Ms. Martinez and her husband did, voiced similar concerns.
“They’ve filled in lakes that have been around forever just so they can build on them, and clear-cut trees like nobody’s business,” he said. “Our name for it is not The Woodlands, it’s Concrete Land.”
The company stated that “the senior development team is ‘essentially the same team’ that has worked on The Woodlands for 25 years.”
Tim Welbes, co-president of The Woodlands Development Company, said the company had complied with FEMA standards for its homes, but that the neighborhood had been overwhelmed by the storm’s waters. “We met the standard,” he said. “This event exceeded the standard.”
Still, at a recent meeting of The Woodlands Storm Drainage Task Force, residents expressed anger at local officials over the damage to homes from Hurricane Harvey — and, for many of them, from earlier floods. This task force was actually formed last year in response to previous flooding, and little had been done to improve the situation before Harvey.
Steve English, 71, said the value of his house has dropped to $400,000 from $800,000 after the two floods. Hurricane Harvey brought 30 inches of water into his home.
“Do we all have to get to where our house is down to $50 and we have to walk out of here naked before you do anything?” he said.
Any fixes could take years, and are quite likely to require coordinating efforts among communities and the state of Texas. Until then, homeowners stew, fret and wait for the next big storm. Raul Giorgi, a real estate agent in The Woodlands for 35 years, owns a home near the Soeders that also was damaged.
He made the same decision to buy there that his customers make — and, like his clients, his ability to dig through years of regulatory decisions and paperwork is limited. They look to real estate agents like him, he said, for information about risks, and he looks to the developers. “Who am I? I’m not an engineer,” he said. “All I can do is trust the experts.”
Now, he says, “I personally believe, in hindsight, this should not have been developed.”