DAMMED TO FAIL

Maria Campos wasn’t going to wait till the dam behind her house burst and washed away her home and her family. It was August 26, 2017, a Saturday, and Hurricane Harvey had parked itself over southeast Texas, unleashing biblical amounts of rain. Ivanhoe, where Campos lives, is a tiny town of 1,800 people 100 miles northeast of Houston, and it saw 27 inches in just five days. About 200 feet from Campos’ backyard, Lake Ivanhoe began rapidly filling behind its earthen dam. The front yard had already flooded, washing away her carefully arranged potted plants.

“The water is coming up, up and up,” she recalled. “My husband say, ‘This is serious, because the lake is already full.’ You can see the little fish in my yard. It was like a river.”

Though Lake Ivanhoe dam isn’t huge — about 19 feet tall and 590 feet long — it holds back about 34 million gallons, or enough to fill 50 Olympic-size swimming pools. Not willing to take the chance that the dam would burst and flood her home, Campos and her husband piled their teenage daughter, Karen, and dog, Spicy, into their gray Kia Sportage and settled in with a neighbor on higher ground down the street.

The Camposes weren’t the only ones in trouble. By August 28, three days after Harvey made landfall, lake levels at 14 dams in the Ivanhoe area were rising dramatically. Within Ivanhoe city limits, all five lakes were full and water was rushing over the top of four dams, putting enormous stress on the earthen embankments. If the dams failed, 400 million gallons of water would be unleashed on the town and downstream areas. And because many of the area’s roads run across the embankments, rescuing people stranded in their homes would suddenly become much more difficult.

Officials in Ivanhoe began to panic. Of particular concern were the eight reservoirs on Magnus Branch, a creek that runs through Ivanhoe. At Lake Urland, the reservoir farthest upstream, water rushed over the emergency spillway, digging out a 15-foot-long rut. If the spillway eroded too quickly, it would unleash a wall of water from the lake. As the torrent surged down Magnus Branch, it damaged Electro Lake dam. City officials worried that if the dams on Electro Lake or Lake Urland fully collapsed, a surge of water could topple the five downstream dams in succession, like a row of dominoes. If that happened, dozens of lakefront