Thousands of homes in an area of Shropshire could have been left without water or had supplies disrupted after a fault at a treatment works. Up to 59,000 properties in and around Ludlow may have been affected by the problem at the works at Trimpley, near Bewdley, Worcestershire.
People have either been without water or have experienced "very poor" pressure, Severn Trent Water said.
The problems follows flooding in Shropshire this week after heavy rain.
'Flat out'
The treatment works were shut on Thursday night and warnings were put out to residents in the media on Friday morning.
The water company has had six water tankers feeding water directly into the pipe network to improve the situation in the short term.
The pumps started working again at Trimpley at about 1330 BST on Friday so the site could start feeding water back out into the pipe network.
But there was a chance of further interruptions throughout the afternoon.
A spokesperson for Severn Trent Water said: "We apologise to those customers affected.
"We recognise it's terribly inconvenient, but we're working flat out to ensure supplies are returned."