PAWNEE, Okla. — An expanded inspection of bridges following a record 5.8 magnitude earthquake near Pawnee found no significant damage, the Oklahoma Department of Transportation said Friday.
State highway system bridges within a 60-mile radius of the epicenter of Saturday’s quake were inspected, and all are now open to traffic and safe for travel, the department said.
The agency initially inspected 180 bridges within a 30-mile radius of the epicenter, and minor cosmetic damage was found on two. Additional inspections were made Wednesday and Thursday that included 175 other bridges after the U.S. Geological Survey upgraded the magnitude of the temblor from the initial 5.6 to 5.8, making it the strongest earthquake in recorded state history.
“We are very conservative and deliberate in our approach to bridge inspections following an earthquake because our first priority is the safety of the traveling public,” said Mike Patterson, executive director of ODOT. “With this weekend’s earthquake being the strongest recorded in Oklahoma, we inspected bridges in a greater radius than our policy requires.”
The department’s earthquake policy calls for inspections beginning with a 5-mile radius on a 4.7 magnitude temblor, expanding to a 30-mile radius of an earthquake with a magnitude of 5.4 to 5.8, and within a 60-mile radius of an earthquake with a magnitude of 5.9 to 6.2.
The U.S. Army Corps of Engineers’ Tulsa District also has inspected all dams within a 50-mile radius of the epicenter, including dams at Birch, Cleveland Levee, Heyburn, Kaw, Keystone and Skiatook, and found no damage at any of them.
The earthquake damaged more than a dozen buildings and left one man with a minor head injury after a fireplace collapsed on him.
State and federal regulators have ordered the closing of 54 wastewater disposal wells in a 725-square-mile area around the epicenter.
The uptick in earthquakes in Oklahoma during the last five years has been linked to the high-pressure injection of oil and gas wastewater deep underground. Researchers have said it’s too early to tell what may have caused Saturday’s quake, which was located further east than most of the previous quakes in Oklahoma.