Recent small-scale earthquakes near Eagle Mountain Lake in northwest Tarrant County have had no structural impact on the reservoir’s dam, which is in sound condition, the Tarrant Regional Water District said in a news release Wednesday. “We have been closely monitoring instrumentation at the dam and conducting daily visual inspections over the last few weeks,” TRWD Dam Safety Engineer Louie Verreault said. “We have seen no change in the structure’s foundation, embankment or spillways. All indications are that the dam is in excellent condition.”
Verreault, the TRWD’s dam safety engineer for 22 years, and his staff routinely collect information and conduct surveys at each of the district’s dams, the TRWD said. The district, the major supplier of raw water to Tarrant County, also maintains dams at Lake Bridgeport, Cedar Creek Lake, Richland-Chambers Reservoir, Marine Creek and Cement Creek.
“We monitor conditions at our dams year-round,” Verrault said. “But, we will continue to track this situation closely if the earthquakes continue in that area.” The Eagle Mountain dam is 80 years old, but has been upgraded to meet currrent design standards, the TRWD said. There have been approximately 20 minor earthquakes, doing little or no damage, reported in North Central Texas in the past several weeks. A number have been concentrated in an area in or near Azle, which is west of Eagle Mountain Lake and straddles Tarrant and Parker counties.
There has been considerable speculation that injection wells, into which polluted wastewater from oil and natural gas operations is disposed, might be a contributing factor in the quakes. But no specific cause has been determined. –Jack Z. Smith, Special Projects Reporter, Fort Worth Business Press