IRVING, Texas -- A wastewater treatment plant malfunction caused up to 70 million gallons of raw sewage to back up, but only about 3 million gallons of that flowed into a North Texas river, a state official said Thursday [April 1]. Officials first feared that the problem could threaten fish downstream, but that did not happen, said Frank Espino, regional director for the Texas Commission on Environmental Quality's Dallas-Fort Worth office.

Oxygen levels never dropped low enough to cause fish harm, according to tests conducted by investigators. "A major problem was avoided," Espino said, praising the Trinity River Authority's handling of the malfunction. "TRA did a very good job of getting it to work as soon as they could."

River authority crews were cleaning up the sewage that escaped and monitoring the stream Thursday. The stench from the leak Wednesday closed part of a golf course and a park near Interstate 30 where raw sewage covered the ground. The force of the flow launched at least eight manholes into the air and geysers of raw sewage rose as high as four feet.

"Take the worst thing you've ever smelled and multiply it by 10," said Len Stahly, 71, who played a full round at Twin Wells Golf course even though the front nine was closed. He played the back nine holes.

[COMMENT: God forbid that these poor golfers have to smell some sewage as they drive their air-polluting golfcarts along lush fareways irrigated with a million gallons of precious water a day. GOLF IS GOD! Or so it seems. What skewed priorities Americans have. I never cease to be astonished. R.]

State and federal environmental regulators were reviewing what caused a gate at the Trinity River Authority's east Grand Prairie treatment plant to malfunction, blocking all sewage from getting into the plant for a half-day. The smelly mess backed up into low-lying areas nearby, then flowed into the river. State environmental officials estimated that with the plant shut down that long, 50 million to 70 million gallons backed up -- the equivalent of 150 to 200 acres covered one foot deep. The plant processes as much as 140 million gallons of sewage daily.

The Texas Parks and Wildlife Department had been notified Wednesday of a possible major fish kill from the sewage overflow, Espino said. "It appears at this point that none of that is going to happen," he said Thursday. "Everything appears to be working out."

Attempts to use cranes and cables to raise the problem gate on a 9-foot-diameter pipeline had failed Wednesday. Crews resolved the problem shortly after 4:30 p.m. -- almost 12 hours after it was discovered -- by opening the plant's only other gate, which had been closed for construction, said spokesman John Jadrosich.

Divers were called to fix the problem, authority officials said. Irving city officials closed Trinity View Park, parts of which were submerged in sewage.

Another sewage line blockage was reported Wednesday at a water treatment plant in Benbrook, just southwest of Fort Worth. It caused about 2 million gallons of raw sewage to spill into the Trinity River. Water from Lake Benbrook was being used to dilute the sewage, Benbrook officials said.

The Trinity River Authority serves parts of 20 cities, including Dallas and Fort Worth. Irving is about seven miles west of Dallas.