KATY — The crowd of more than a hundred wore yesterday’s clothes as they gathered on the wood floor of a dance studio near their flooded neighborhoods.

“So most of you do not have flood insurance?” attorney Mo Aziz asked.

They responded in a chorus of “No.”

On the minds of many in the room was another question. Who is to blame?

They could sue developers, real estate brokers and others, Aziz explained, but these cases are complex. “Unfortunately, there’s no easy fix for your situation.”

It was the latest piece of bad news for these residents of one of Houston’s western suburbs. First, the water had risen so fast that many escaped with few belongings. Then, after the rain stopped and they returned to the shallow, murky and potentially toxic lake that now submerged their neighborhood, authorities refused to let them back in.

They had begun to realize that their $200,000 to $300,000 homes were inundated because — though no one had ever told them — these houses were built just inside the edge of a man-made reservoir built to protect Houston from flooding.

Adequately preparing for a storm like Harvey may have been impossible. Harris County officials are calling it an extremely rare 10,000- to 20,000-year rainfall event. Still, as people across the Houston area adjust to the idea that their homes could remain flooded for weeks, many are beginning to learn that they lived in places more at risk than they understood.

When the rains kept falling, federal officials made choices about when to open the floodgates of two swollen reservoirs upstream of Houston that threatened to spill dangerously into the city. The decision of when to open the gates and how much effectively sacrificed some neighborhoods to avoid a larger calamity. But as the water has receded, the choice is now feeding a sense among many people that more than Mother Nature may be at fault for their misfortunes.

Many residents whose homes are within the bowls of the reservoirs say they should have been better warned that the reservoirs themselves could put their property at risk.

“I was going back through the paperwork of when I bought my house,” said Tamara Alford, who evacuated a flooded home with her son and daughter. “Thinking there must be something about that in here.”

In December 1935, a storm dropped enough rain on Houston to flood Buffalo Bayou, a normally slow-moving river that runs through the city. The water killed seven or eight people and prompted officials to study what could be done to avoid another disaster.

A decade later, the U.S. Army Corps of Engineers built two large reservoirs in what was then ranchland west of Houston. The Barker and Addicks reservoirs would serve as huge storage tanks for water from creeks that fed into the bayou. Rather than let the water run straight in and flood Houston, the reservoirs could store the water and dissipate it slowly.

The corps built earthen dams along the eastern sides of the reservoirs to hold the water in. Over time, the agency built floodgates to control the flow of water through the dams.

Most of the time, the reservoirs would be dry and the floodgates open. The land could be used for soccer fields, golf courses and dog parks. Only when heavy rains came would the gates be shut so the reservoirs could hold water.

The corps bought all the land inside the reservoirs that would be covered by water in a 100-year rain event, meaning one with a 1-in-100 chance of happening any given year. But the reservoirs could hold more water than that. Land at the western edges of the reservoirs, which would be covered in water during a greater than 100-year storm, remained privately owned.

For a long time, it made little difference whether the private property would ever be needed as part of the reservoir — it remained ranchland. But in recent decades, developers replaced pastures with brick homes in neatly subdivided lots.

As Harvey approached on Friday, Aug. 25, the Corps of Engineers closed the heavy floodgates of the two reservoirs.

Hard rain fell that entire weekend, and the reservoirs became vast lakes, working as designed to spare Houston from a flood. But by Monday, the reservoirs were nearly full. The water had spread to the edge of the government-owned land and was overtaking the neighborhoods beyond. The water had risen in height too, toward the tops of the dams.

The reservoirs are designed so that if they become full, water will not spill over the dam tops. Instead, it will find its way around the sides of the dams, which are at lower elevations. In the Addicks Reservoir, this was starting to happen.

Rather than let the water keep rising, the corps opened the floodgates to let a controlled amount of water escape. Normally, this would have been done after a rain subsided, and at a flow rate of 4,000 cubic feet per second. But corps officials opened the gates wider than that so the water could escape much faster. They had to begin to get rid of it. They did so knowing it would flood neighborhoods downstream.

“That’s the part that we don’t take lightly at all,” said Edmond Russo, a deputy district engineer for the corps’ Galveston District. But they felt they had no choice. If they hadn’t opened the gates, water would have spilled out more dangerously around the sides of the dams.

Debris left behind from the evacuation litters the median of Mason Road near the entrance to the Cinco Ranch Canyon Gate subdivision in Katy on Sept. 2, 2017. (Smiley N. Pool / Staff Photographer)

'We can't go through the night'

By 7 o’clock Monday morning, water flooded the street in front of Tam Trinh’s three-bedroom brick home, where she lived with her husband and three kids, ages 6, 8 and 10.

The home sits near the southwestern corner of Barker Reservoir, along its upstream edge, in a neighborhood called Canyon Gate, part of a larger suburban development near Katy named Cinco Ranch.

The opened floodgates were letting water escape downstream, through the reservoir and away from Trinh’s home, down toward Houston. But the corps hadn’t opened the gates soon enough to spare Trinh and her neighbors from the expanding reservoir lake.

“We didn’t believe we would be flooded, because we are in a high spot,” Trinh said.

But the rain kept pounding down, and the water kept rising. It rose so fast you could see it coming, creeping up driveways hour by hour, like a living thing.

By noon, the water had leapt halfway up Trinh’s driveway. By 2 p.m., it reached the stone archway that covers her front porch. By 5 p.m., it covered the porch and was about to advance through her front door.

“I said we can’t go through the night, because the water kept rising,” Trinh said.

Trinh and her husband, who had a kidney transplant only weeks ago, corralled the kids, grabbed what they could, and hopped into a Samaritan boat that was cruising the neighborhood. Families at lower elevations nearby had been evacuating throughout the weekend.

On Tuesday, the phone lines at a nearby volunteer fire department lit up, and a boat crew from the Granbury Volunteer Fire Department had driven south to help.

In red rubber boats, the rescuers drove house to house, “some of them with 6 feet of water in them,” Granbury Fire Chief Brent Blackmon said.

Texas DPS Trooper Mike Blackwell takes notes on a resident's pet and address before going out on a search boat into the Cinco Ranch Canyon Gate subdivision Sept. 2, 2017. (Smiley N. Pool / Staff Photographer)

Land's purchase

Richard Long has worked for the Army Corps of Engineers for more than three decades, much of it overseeing operations of the Addicks and Barker reservoirs.

“When we bought the land back in the '40s, we bought the minimum land necessary for the project,” he explained.

The dams were built to hold larger lakes than could fit on the land the corps had bought, he said. But the agency had no control over what was built outside of its property line.

“The development was up to developers who bought the land, and the builders, and then the county to approve those developments,” Long said. The corps owns the land that will be inundated in a 100-year flood, and developers were free to build outside of that.

There’s no requirement for builders or real estate brokers to disclose flood risks in places safe from a 100-year event. “It’s never been a secret. We’ve advised the public on numerous occasions,” Long said. But the area’s population is somewhat transient because of the oil industry.

“So with that being said, many of them truly did not know they were living in the reservoir,” Long said.

Did the developers know?

“I can’t say they all knew it. Some of them did,” Long said. “Because some of them called us and asked us.”

Did the corps advise against building?

“We’ve got to be very careful about advising,” Long said. “We give facts. It’s up to them to take those facts and make a determination as to the amount of risk they’re willing to take.”

While most of the area around the reservoirs sits in Harris County, Trinh’s neighborhood is in Fort Bend County. That county’s engineer, Richard Stolleis, said that there, as in most places, developers are restricted in building inside a 100-year floodplain.

“But beyond that, we don’t have the authority to tell them they can’t do it,” Stolleis said.

He likened building a home inside the reservoir to building just above that level near a river. If the river rises beyond the 100-year flood mark, the home gets flooded.

1 / 4Fort Bend County Judge Robert Hebert raises his hand as he takes questions from Cinco Ranch Canyon Gate subdivision residents who gathered to vent their frustration at a police road block outside their neighborhood on Saturday, Sept. 2, 2017.(Smiley N. Pool / Staff Photographer) 2 / 4A resident of the Cinco Ranch Canyon Gate subdivision holds the American Flag during a demonstration at a police roadblock outside their neighborhood on Saturday, Sept. 2, 2017.(Smiley N. Pool / Staff Photographer) 3 / 4Law enforcement officer put up police tape in front of a group residents of the Cinco Ranch Canyon Gate subdivision on Saturday, Sept. 2, 2017, in Katy.(Smiley N. Pool / Staff Photographer) 4 / 4Residents ride in a military truck through flood waters left by Hurricane Harvey near the Cinco Ranch Canyon Gate subdivision on Saturday, Sept. 2, 2017.(Smiley N. Pool / Staff Photographer)

Blocked from their homes

By Wednesday afternoon, the sun came out, and most of the families who wanted to leave the neighborhoods near Trinh’s home had been evacuated.

“We were in there all day, cruising around and checking things out,” said Blackmon, the Granbury fire chief. “Some people wanted to stay.”

The homes still had electricity, and many had second stories allowing families to escape the water downstairs.

Many of those who had evacuated now faced a new problem. They wanted to get back to their homes to check the damage, and to retrieve pets, prescriptions and everything else they’d left behind. But the county judge had issued a mandatory evacuation order, so they couldn’t get back in.

Fort Bend County sheriff’s investigator Patrick Douglas spent his day behind yellow crime scene tape explaining to exhausted, often furious residents that it could be weeks before they could come back.

They wanted to know: How high’s the water? When will it go back down?

“All we are doing is saving people now. We are not going in for property, pets or anything like that,” Douglas explained to the endless stream of residents.

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'We just want our homes back'

On Thursday, frustrated residents organized the meeting inside a dance studio run by one of the flood victims. They invited Aziz and another attorney who spoke with them from under the disco ball.

Emily Li was one of the many who had no flood insurance. When she’d bought the home in 1998, the developer told her it wasn’t required, she said. “So I bought it [flood insurance] the first year, and the second year I dropped it. I remember vividly.”

Aziz nodded. “So that would be a case, potentially, against your developer or your real estate agent, or maybe both,” he said. After the meeting, the attorneys began collecting information from residents interested in launching cases on contingency.

Saturday morning, dozens of tense residents gathered for a protest at the entrance to their Cinco Ranch neighborhoods. They sweated in 90-degree heat behind the crime scene tape. It will take a couple of weeks, assuming little new rain, for the reservoir to drain and their homes to unflood.

Fort Bend County Judge Robert Hebert arrived and spoke through a county patrol vehicle’s loudspeaker, reassuring them he would pursue federal money to help them.

One woman sat on the road near where it dead-ends into water, holding a sign: “We just want our homes back.”