United Utilities has apologised to residents in the PR3 area after water stopped flowing in some areas.
Towns such as Bilsborrow, Garstang and Longridge have been affected and the company say its inspectors are investigating the problem.
In a statement released at 9.50am this morning, it said: “You may have noticed that the water is coming out of your tap slower than usual or may have gone off altogether. We have one of our inspectors looking into this at the moment and as soon as we know what the cause of the problem is we’ll let you know.
“We’re sorry about this and will try and get your taps flowing normally as quickly as we can. We’ll keep you posted as soon as we know what’s causing the problem.