"We've had a hundred-year flood type rain. It was a record for the day. We're a relatively flat place that can't take that type of rain," city spokesman Garett Nelson said after Thursday's downpour.
At least 100 buildings, both commercial structures and houses, were damaged, Nelson said.
The nonstop rainfall caused pumps to fail at Jones AT&T Stadium, and the football field flooded with water an ankle deep, the Lubbock Avalanche-Journal reported in its Friday online editions.
The field was drained on Friday afternoon, and officials said Texas Tech's game with Southern Methodist would go on Saturday evening as scheduled.
Tech spokesman Chris Cook said the pumps can handle typical rainfall.
"They've never let us down before," Cook said. "They were just overcome with so much water."
National Weather Service meteorologist Ron McQueen said the rains were connected to a Pacific storm, Tropical Depression Lowell.
"It snuck in and for us it was a major storm, no question about it," McQueen said.
Nelson didn't know how many people were displaced but said one person stayed in the city's shelter Thursday night.
Lubbock County inmates filled 4,000 sandbags for heavily flooded areas after at least 100 calls came in for sandbags, Nelson said. Later, city employees took over the tasks of filling the sandbags and delivering them to residents.
Rains eased and floodwaters began to recede early Friday, but officials urged people to stay home.
"If they're home they won't be driving into high water areas, and the less movement we have, the less water will be driven into people's homes by wave action," Nelson said.
Despite the flooding, officials said Lubbock would remain on the list to possibly shelter evacuees from Hurricane Ike as it approached the Texas coast Friday.
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