Schools, businesses and homes across seven boroughs in England were hit by a Thames Water outage on Monday, from a burst water main reportedly leaking 750 litres a second.

About 6,000 properties across five south London boroughs and two Surrey boroughs had no water supply or low pressure, Thames Water said.

Thames Water apologised for the lack of water. A spokesperson said: “Our specialist team is now on site and working to stop the water flooding from the broken pipe.”

Schools and colleges were forced to close across the boroughs. Esher College, a sixth-form college for 2,000 students, was among those forced to send pupils home and shut their doors. The college said: “Due to a major water outage effecting the KT10 area and our campus we are closed on Monday 28 September.”

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Kingston grammar school also closed, as did Long Ditton infant and nursery school, Thames Ditton infant school and Hollyfield school and sixth-form centre in Surbiton.

Monica Harding, the Liberal Democrat MP for Esher and Walton, Surrey, said it was her understanding that water was leaking at 750 litres a second early on Monday morning after a large main burst. The community was left without water from about 5am. “It is completely unacceptable,” she said.

“We need an urgent response from Thames Water to get water supplies back on as soon as possible and to protect vulnerable communities.”

Some reports said a contractor had struck the water pipe with a digger, causing a 4ft rupture in the pipe in the Walton section.

Helen Ryder, who runs a flower shop in Thames Ditton, said: “Our priority is to make sure staff have water, but we need to make sure the flowers do too. Hopefully we have enough water, but people come before flowers.”

Parents at Hollyfield school and sixth-form centre received a message from the school which said: “There is a significant issue with water supply in the local area … Whilst we have water at the moment it is not replenishing at the same rate it is being used and so our supply will run out at lunchtime. This means that it is unsafe for students to remain on site.”

Thames Water said it would deliver water to registered vulnerable customers and open bottled water stations later, at locations yet to be confirmed.

Thames Water said the following postcodes could be affected: CR4, KT1, KT10, KT12, KT2, KT3, KT5, KT6, KT7, KT8, SM4, SW16, SW17, SW18, SW19, SW20, TW10 and TW16.

Paul Kohler, the Lib Dem MP for Wimbledon, said he had contacted Thames Water for more information after reports of a water outage across Wimbledon, New Malden, Raynes Park and Morden, in south London. He told followers on X that he would share any updates he received.

Harding said: “My worry is that decades of underinvestment in our infrastructure and poor regulation may be causing incidences like this. Right now, however, the priority must be getting water back in our taps.”

A spokesperson for Thames Water said: “Our engineers are making progress on repairing the burst in Molesey but it is likely to take some time to complete.

“We are rerouting water in the area to reduce the impact on customers while we work to fix the burst. Water deliveries are being made to customers who are on our priority services register. We will be opening bottled water stations this afternoon and will provide their locations once confirmed.

“The number of properties affected has now been reduced to less than 6,000. We again would like to say sorry to our customers and reassure those who are still affected that we are working to restore their water supply as quickly as possible.

“The latest updates will be posted on our website, thameswater.co.uk.”