Tens of thousands of homes in Hampshire are without water because of a technical fault at a Southern Water supply works.

About 58,000 homes in Southampton, Romsey, Eastleigh, Totton and parts of the New Forest have outages after a problem at the Testwood water supply works prevented water from leaving the site.

The disruption is expected to last until the weekend, Southern Water said. More than 20 schools were forced to shut as they had no water.

It comes as it was announced Southern Water customers will face the highest bill increases in England and Wales under Ofwat’s price review, with costs to rise 53% by the end of the decade. The average increase is 36%.

Southern Water said: “Overnight our teams have fixed the problem at the Testwood water supply works and restarted the site. We’re now filling up the reservoir again with drinking water, ready to restore supply. This is a gradual process which must be done carefully and safely, but customers will start to be reconnected later today. We are working towards all customers being back in supply by the weekend.”

Bottled water is being delivered to vulnerable customers and bottling stations are being set up, the company added.

The Department for Environment, Food and Rural Affairs said: “The water minister, Emma Hardy, has met with the chief executive of Southern Water to make sure the company is taking urgent steps to support residents and resolve the issue as soon as possible.

“Incidents like this are why we are forcing water companies to double the compensation provided to customers for supply issues. We are also carrying out a full review of the sector to shape further legislation that will transform how our water system works, increasing investment to upgrade crumbling infrastructure and strengthening regulation to better hold companies to account.”