OMAHA — It will likely take a week to restore power to everyone in the Omaha area after 80 mph winds tore through much of eastern Nebraska, uprooting trees, damaging homes and killing two people in a neighboring city.

Tens of thousands of people remained without power Saturday, and utility officials predicted restoring power to everyone will be difficult. Friday’s storm was one of the worst the Omaha Public Power District has dealt with, CEO Gary Gates said.

The storm ripped off some roofs and damaged others, shattered windows and uprooted trees. Several homes will be declared unlivable, but city and county officials did not know how many.

Police in Council Bluffs, Iowa, across the river from Omaha, said two people died when a tree fell on the car the two were in. A woman with them in the car was injured.

No other deaths or serious injuries were reported in the area.

“This might not have been a tornado, but we’ve had homes destroyed, significant tree damage and thousands of people without power,’’ Omaha Mayor Mike Fahey said Saturday. But he predicted the city would recover, just as it did after two tornadoes struck earlier this month, damaging several homes but causing no deaths or serious injuries.

Some people spent Friday night in a Red Cross shelter at the Ralston Fire Department, according to a press release. The Red Cross of Lincoln also sent six volunteers and an emergency response vehicle to assist those already helping in Omaha.Journal Star reporter Zach Pluhacek contributed to this story.

West of Omaha, the storm’s wind and hail devastated fields of corn and soybeans, but it wasn’t immediately clear how many acres of crops were affected. Some fields in south Omaha suburbs were relatively untouched.

The storm also damaged the Qwest Center north of downtown Omaha, forcing swimmers practicing for U.S. Olympic trials to flee pools and run for cover.

Officials closed the building to examine it after superstar swimmer Michael Phelps and hundreds of other athletes were herded into hallways because of a tornado warning. Water poured into the building, down arena steps and onto the deck of the competition pool during the storm.

Swimmers returned at 6:30 a.m. Saturday for the first of two practice sessions. The eight-day meet to decide the U.S. Olympic team begins Sunday, with 1,250 swimmers competing.

The high winds of 30-40 mph the National Weather Service predicted for Saturday afternoon never materialized, so a wind advisory for the Omaha area was canceled. A dry weekend forecast was expected to help the cleanup effort.

OPPD said about 45,000 customers remained without power as of 8:30 p.m. CDT. At the peak of the outages, 126,000 customers had no electricity.

After the utility completed its initial damage assessment, Gates said some OPPD customers will likely remain without power until next Saturday. Gates promised to restore power as soon as possible, but he said the work would is tedious and time consuming.

“We’ve made very good progress so far with our restoration efforts, but as the work proceeds we’re going to see fewer repairs that restore power to large numbers of customers,’’ Gates said.

He said the worst damage was on a line from North Bend in Dodge County southeast to Bellevue on the Missouri River, south of Omaha.

The news conference was held in Omaha’s Memorial Park a few hundred feet away from where workers were cleaning up the soggy blankets concertgoers left behind when the storm hit. The city canceled the free show because of the weather, and the stage was being dismantled Saturday.

A few blocks north of the park, Tracie McPherson and her family were cleaning up the mountain of tree limbs that filled her front yard.

The mature trees were one of the attractions of the neighborhood for McPherson when she moved in less than a month ago. Now she said she is thinking the trees need to be trimmed back.

Mostly, McPherson said she is grateful that her family is OK and the damage wasn’t worse. Most of the tree limbs fell away from the house although some of McPherson’s clay roof tiles were damaged.

McPherson planned to clean up what she could this weekend because a tree company told her it couldn’t have anyone at her house before Monday.

Two of McPherson’s new neighbors were helping her clean up Saturday morning, and another neighbor lent her a chain saw.

“It’s a workout,’’ McPherson said. “I don’t have to do the elliptical machine today. That’s for sure.’’

Omaha city officials said generator power has restored operations at the city’s sewage plant, so the plant has stopped releasing untreated sewage into the Missouri River.

Public works director Bob Stubbe said Saturday that the plant lost power about 6 p.m. Friday.

Stubbe said untreated waste water from Omaha sewers went into the river until early Saturday, when a generator was powered up and the plant could resume operations.

Officials were warning people not to wade or swim in the stretch of the river that passes by Omaha and for several miles downstream.

The storm “really blew in quick and with a lot of force,’’ said Mike Hinrichs, who was cleaning up tree limbs in his central Omaha yard Saturday. “We were pretty lucky, really.’’

Weather Service meteorologist Van DeWald said teams were out assessing damage patterns so the service could precisely peg the wind velocity.

There were several estimates of 80 to 90 mph, he said.

“As the storm blew across our office (in Valley, west of Omaha), we measured 77 mph before the wind equipment failed,’’ DeWald said.

“I estimated 80 at my house in Elkhorn,’’ he said, “but I don’t have any wind equipment at my house.’’

The rain fell heavily on the area.

Eppley Airfield north of downtown Omaha recorded a 0.57 inches, DeWald said, compared with 0.80 inches at Offutt Air Force Base near Bellevue, south of Omaha.

He said 1.06 inches were recorded in the past 24 hours at the Weather Service office in Valley.

Associated Press Writers Amy Lorentzen in Des Moines, Iowa, and Nelson Lampe and Beth Harris in Omaha, Neb., contributed to this report.