HOUSTON — Harvey dumped a year’s worth of rain on Houston in a matter of days, shattering last year’s above-normal rainfall and bringing this year’s total to an unprecedented 73 inches.
But according to Jim Blackburn, a professor in the Civil and Environmental Engineering Department at Rice University, the storm wasn’t just a natural disaster.
“This was a climate-influenced storm. There’s no question,” Blackburn said. “The temperature in the Gulf of Mexico where the tropical cyclone grew in two days to a Category 4 hurricane was 2 to 7 degrees above normal.”
Blackburn has studied the effects of storms on cities for nearly 40 years. He said that when Harvey came ashore, the storm laid bare another problem decades in the making: the massive paving over of the area’s natural wetlands and prairies.
“We’ve covered our sponge up,” Blackburn said. “The sponge we had here was wonderful. It would hold water, but … in order to develop it you had to drain it. You had to get rid of the water. And as we’ve developed out we’ve dumped water back on ourselves.”
Since the 1950s, nearly 88 square miles of wetlands have disappeared in the Houston area due to development. And the region’s system of canals and bayous are overwhelmed by increasingly heavy storms.
“Basically, Harvey is the new norm,” Blackburn said.
He said a photo of nursing home residents in waist-deep floodwater illustrates the problem. The residents were evacuated, but the home was built on land directly across from a floodplain boundary.
“And part of it is getting an adequate amount of room for that water to come through the city, which means…