Severn Trent Water has been working round the clock over the last few days to keep water supplies going in the parts of of Gloucestershire.
Longhope, Westbury, Blaisdon, Glasshouse and Maisemore areas have been affected following a problem which has developed at the Nottswood reservoir nearby.
Simon Brown, a manager at Severn Trent, said: "At the end of last week we noticed there was a problem with one of the valves on the pipe which goes into the Nottswood reservoir.
"This has meant that levels there are lower than usual. So to help make sure our customers’ water supply is kept flowing, a fleet of water tankers has been mobilised and Severn Trent Water engineers are working round the clock to repair the problem.
“Some of our customers who live in the area near the reservoir may have noticed we have tankers nearby and that their water pressure is lower than usual. Please be re-assured that we’re working hard to get things back to normal and we don’t expect anyone to lose their water supply while we carry out the work.
"We’d like to say sorry to all of our customers that have been affected and hope it won’t be long before the problem is fixed.
“Also, over the last few days water has been flowing around the system in a different way to usual, which is moving sediment. As a result of this, customers may be seeing some discoloured water.
"To help clear this, please run your cold water tap for a while and the water should clear, if it doesn’t please call us on 0800 783 4444. We’re doing all we can to make sure things get back to normal as quickly as possible and we’d like to say sorry for any inconvenience this may be causing.”