Affinity Water urges essential water use only
A water company has urged customers to avoid all non-essential water use.
Affinity Water said "urgent action" was needed in areas of Essex and Hertfordshire to "conserve reservoir supplies for everyone".
The water supplier said recent water demand had surged from 209 million gallons (950 million litres) a day to 242 million gallons (one billion litres) due to the hot weather.
It added it was "working around the clock to maintain supplies".
Some areas of Buckinghamshire, Surrey and North London are also affected.
Affinity said that as the Met Office had issued a rare alert for extreme heat , an increase in water demand was set to continue over the coming days.
"To make sure we have enough water to go around for drinking, washing and cooking during this red weather alert, we're appealing to customers to avoid all non-essential water use now, such as hosepipes and sprinklers," a statement said.
It added it was "working around the clock to maintain supplies and pressure" but was "appealing for urgent help from the community to avoid non-essential water use immediately".
The company said that if customers noticed a lower water pressure than normal, this was all part of it controlling water to keep it flowing through the network.
To avoid these low pressures it said it was making sure its treatment works and pumps were working at maximum capacity, reducing leaks and filling up storage reservoirs as much as possible plus pumping extra water into the network to where it was needed most.
It said the most urgent action was needed in:
- Bishop's Stortford
- Buntingford and surrounding villages
- Chesham
- Clandon
- Epping
- Harlow
- Hertford
- Kelvedon Hatch
- Northwood
- Oxheywood
- Roydon and surrounding villages
- South Oxhey
- Stansted
- Stebbing and surrounding villages
- The Ongars
- Theydon Bois
- Ware
- Woking
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