TEWKESBURY, England (CNN) -- At least 250,000 people remain without electricity, and at least another 140,000 homes are not receiving fresh drinking water, British officials said Tuesday.
A British Red Cross member chats with flooding victims in Abingdon, central England.
Water supplies are not expected to return to full working order for at least a week and the British military is distributing 3 million bottles of water per day.
Fire and rescue workers have just started the process of inspecting the Mythe Water Pumping Station in Tewkesbury to restore water supply to 70,000 customers in Tewkesbury, Gloucester and Cheltenham, Gloucestershire Chief Constable Timothy Brain said Tuesday. The work is expected to take two days.
Meanwhile, a major electricity substation serving a half million homes in western England and threatened by rising water has passed the crisis stage thanks to a "superhuman effort" overnight, Brain said.
"The crisis may have passed last night, the ongoing emergency is not over," Brain said at a news conference in Gloucester. "The water is still high surrounding Walham (substation). There is still the prospect of further high peaks later today about the same time as yesterday at midnight."
About 1,000 Royal Navy personnel constructed an emergency flood defense barrier to prevent the flooding of the Walham substation on the outskirts of Gloucester. See seven-day weather forecast for Gloucester
Brain noted that a massive amount of water retained in the nearby Severn-Avon river basin "is going to give us problems ... for several days to come."
The flooding -- the worst to hit western England in 60 years -- has affected power stations and water treatment plants in the counties of Gloucestershire, Herefordshire, Worcestershire and Oxfordshire.
Above-normal water levels in the two major rivers -- the Thames and the Severn -- are slowly falling and British officials say the rain -- which is due to arrive in the area Wednesday -- is not likely to cause further flooding.
There are fears that the River Severn, which flows through the historic city of Gloucester, could overtop its banks. The river is already nearly 15 feet above its normal level for this time of year. In the town of Evesham, the River Severn is more than twice its normal width. See images of the flooding's devastation »
More than 40,000 customers lost power on Monday when British officials took the Castlemeads substation off-line after it was flooded. A British power representative said Tuesday that more than half of those customers were put on a back-up supply while engineers worked overnight to restore power to the remaining customers.
Water damage to the Castlemeads substation is still being repaired, he said.
The town of Tewkesbury is also flooded -- video from the area showed dozens of cars and homes under several feet of water. Rescue vehicles were spotted on Tuesday driving through several inches of floodwater to reach residents. Watch how the waters have left the town "marooned" »
So far this month England has had nearly two-and-a-half times its normal rainfall.
Hundreds of people in the worst affected areas were plucked to safety by helicopters of the Royal Air Force and boats. Rescuers transporting the elderly and the sick to safety using inflatable boats was a common site.
Prime Minister Gordon Brown visited Gloucester on Monday and promised to mobilize resources from across the country. He also announced increased funding for flood and coastal defenses across the country.
"Like every advanced industrialized country, we are coming to terms with the issues surrounding climate change," he said. The prime minister described the flooding as unprecedented.
He pledged $1.6 billion in flood relief.
The government has been criticized over the quality of flood defenses and for a slow response to the crisis.
The wet weather for much of June and July across England and Wales has also affected crops. Farmers are predicting low yields and higher prices -- with several crops due to be harvested in the next month.
Insurance companies are expecting claims worth hundreds of millions of dollars because of flood damage. E-mail to a friend
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