New data shows Houston-area suburb sinks more than a foot in nearly two decades

KATY, Texas (KTRK) -- A Houston suburb has sunk more than a foot over nearly two decades, according to new data.

The report stated that the fast-growing community of Katy is sinking, but this particular suburb isn't alone.

Data showed parts of northwestern Harris County are in the same boat, and that it has to do with the amount of groundwater withdrawal in the area.

The Harris-Galveston Subsidence District said that when large amounts of groundwater are removed, it causes the land to sink.

Officials from the district said that while the process is slow, it's also irreversible.

"It's alarming and shocking. It's kind of scary, too, at the same time," Katy resident, Maria Shelton said.

Katy had the greatest subsidence rate in the region, according to the district.

The district tracks that data through 190 GPS monitoring stations.

"We also saw areas of subsidence occurring all throughout northwestern Harris County in areas like Katy, Cypress, Tomball, Spring, The Woodlands; all of those areas are showing active subsidence," Casey Hughes, HGSD Communications Director, said.

The district said subsidence is the gradual sinking of the land caused by groundwater withdrawal.

"The areas that we are seeing actively subsiding, those areas still rely heavily on groundwater to supply their water demand," Hughes said.

The process is slow, but permanent, according to the district.

"Damage to infrastructure, like your homes, roads, bridges, buildings," Hughes said. "It can also increase our flood risk."

Other parts of the region have also felt the impact, like the Brownwood Subdivision in Baytown.

"Some areas, like in Baytown, they experienced about ten feet of subsidence over the course of about four decades," Hughes said.

But the district said those areas aren't seeing any subsidence anymore because of the groundwater regulations they put in place.

They said the focus now shifts to the northwestern parts of the county as well.

"There is a conversion requirement by 2035 for those areas to fully transition from groundwater to alternative water supplies," Hughes said.

The subsidence district said that if that doesn't happen, there is a financial penalty of $12,520 per million gallons of water.

Katy residents told ABC13 they hope the sinking slows down before any problems rise to the surface.

"How can we change it? What does that look like for us being here in the Katy area? Because we love Katy," Katy resident, April Thompkins said.