The driest winter and spring in 35 years has left reservoir levels "worryingly low".
Severn Trent said it was concerned about dwindling reserves at Cropston and Swithland reservoirs, which supply many homes in the county.
Swithland is at 65 per cent capacity and Cropston has fallen to 55 per cent.
Normally at this time of year, they would be 70 per cent full.
The firm asked customers to restrict water use until rain replenished stocks.
A Severn Trent spokeswoman said: "While we are not at panic stations, the levels of the reservoirs are a worry.
"In the case of Cropston, where it is very low, we will consider tapping it off and using supplies from elsewhere in the region until it recovers.
"The past seven months have been the driest since 1976 and because the levels are so low we are looking to reduce demand.
"With the warm and dry conditions set to continue, we are appealing to customers to help do their part by conserving water supplies."
Martin Kane, Severn Trent's customer relations director, said: "The weather throughout March and April particularly has been exceptionally dry.
"We are doing everything we can to manage the balance between our reservoir, river and groundwater supplies.
"More rain isn't a popular idea but it is what we need, preferably spread over several weeks."
The company said it was not considering a hosepipe ban or any other enforced restrictions at this stage.
However, Mr Kane said: "The more steps we can all take now – both as a company and as individuals – the better placed our water supplies will be if dry, hot weather continues.
"Things you can do to help include taking showers rather than baths, fixing dripping taps, using the dishwasher only when full and resisting the temptation to use a hosepipe or sprinkler."
An estimated 495 million litres a day leaks from Severn Trent's network of pipes.
Malcolm Hunter, from the Leicester branch of Friends of the Earth, said: "I think we all accept it's a good idea to reduce our water consumption but Severn Trent needs to do much more to stop the staggering amount of water being wasted each day.
"If water is in short supply, it is Severn Trent which can do a lot to solve the problem."
The company is within the target set by water regulator OfWat of no more than 500 million litres of leakage a day.
The company spokeswoman said: "Last year, which included the coldest December for 100 years, was a difficult year for leakage.
"We suffered a huge number of bursts due to the freezing weather.
"Last year's leakage doesn't really impact the position we're in as far as water resources are concerned as it's the very low rainfall and high customer demand that's affecting us."
In December, Severn Trent announced half-year profits were down by 50 per cent on the previous period, to £101.1 million. 作者: leumas 时间: 2011-5-24 17:32
