Emergency officials lifted a mandatory evacuation order for low-lying areas in downtown El Paso after receiving word that an earthen dam holding back more than 6 million gallons of water from the Rio Grande is no longer an imminent threat.

Crews in Mexico worked overnight to reduce water levels at the dam, which U.S. Army Corps of Engineers officials said Thursday was dangerously close to bursting.

Julie Baldwin, city spokeswoman, said crews were able to reduce water levels at the dam by 10 to 20 feet since last night with the help of heavy-duty pumps and the construction of drainage culverts to divert overflow.

Nearly 1,000 El Paso residents sought refuge in the city's convention center Thursday and were being told Friday afternoon that it was safe to go home.

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The aging dam became a threat after nearly a week of heavy showers soaked the west sides of border neighbors Ciudad Juarez, Mexico, and El Paso. The rain swamped mountainside neighborhoods, caused flash floods and rocks slides, and led to the death of a construction worker hit by an out-of-control tractor-trailer on a flooded roadway in El Paso.

The National Weather Service had predicted a 50 percent chance of rain and thunderstorms Friday, but only a few brief showers were reported by Friday afternoon. A flash flood warning was issued, but emergency officials said water levels had reduced enough that the dam was no longer a threat.

Mayor John Cook said Thursday that a dam brak would be "like a tidal wave hitting El Paso."

Authorities in Ciudad Juarez evacuated more than 4,000 families living near the dam earlier in the week as a precaution and kept an eye on 69 smaller dams throughout the city.

Mexican federal officials declared the city a disaster area and estimated the damage at about $45.5 million. Democratic lawmaker Silvestre Reyes estimated damage on the American side could reach $250 million.

Texas Gov. Rick Perry and Reyes said Thursday they each had asked the federal government to declare El Paso a disaster area after the flooding.