Portions of The Woodlands, primarily in the northwestern segments along the Research Forest corridor, sit atop three fault lines.
Shuhab Khan, an associate professor in the department of Earth and atmospheric science at the University of Houston, said faults in The Woodlands likely formed by one of three ways: through sedimentation, salt deposits and subsidence.
“[The faults] formed primarily because of the rivers bringing sediments into the area, and the sediments are moving toward the ocean,” Khan said.
Some faults, he said, are formed because of salt deposits in the Houston area.
“In the Houston area, there is a lot of salt, and salt has a lower density than water and tries to come up [to the surface] by itself,” Khan said. “So salt comes up and fractures the ground.”
Subsidence is a result of increased groundwater usage. As more groundwater is pumped from below the Earth’s surface, fractures occur at ground level, Khan said.
“In The Woodlands, primarily it’s the groundwater [that causes faults],” Khan said.
Fault lines in the Houston and Woodlands areas move an average of 1 centimeter per year, he said.
“That means that’s an average,” Khan said. “It may move 2 centimeters next year and after that it may not move at all. Not every fault is active.”
Michael Bowden, owner of Bowden Appraisals, said local faults typically have a negligable affect on property values.
“In most cases in this area the answer is zero, none,” he said. “However, if it’s an active fault line, and there are several of those around, it could have an affect on value.”