South West Water has announced a hosepipe ban - its first in 26 years - to cope with drought conditions in Cornwall and Devon.
The restrictions are due to come into force from Tuesday 23 August.
The announcement follows a string of hosepipe bans in other parts of England as water companies look to save resources during a period of prolonged dry weather.
A drought was declared last week across large parts of the country, including Lincolnshire and Northamptonshire, Kent and South London, Herts and North London, East Anglia and the East Midlands.
South West Water said on Monday it would be taking action to preserve water in Devon and Cornwall, which is also affected by the drought.
The hosepipe ban will affect the whole of Cornwall, as well as a small area of northwest Devon.
“It’s the first time in 26 years but we’ve been left with no other choice. We need to have a hosepipe ban now to protect our precious water,” a spokesperson said.
“We’ve done our best to avoid this ban. We’ve increased the amount of water we can store, doubling it since the last drought in 1976.
“We’ve opened reservoirs, installed a new borehole, and improved the way we can move water across the region to help keep everyone’s taps running.”
The hosepipe ban will come into force from 23 August, the water company said.
Three water companies - Welsh Water, Southern Water, and South East Water - have already imposed hosepipe bans across their areas.
Yorkshire Water will launch a ban on 26 August and Thames Water is planning one in the coming weeks.
It follows months of sparse rainfall and bursts of extreme heat, which have resulted in water shortages, depleted resevoirs and the driest July since 1935.
Dan Stroud, a Met Office meteorologist, said intense showers forecast over the next few days - which follow soaring temperatures - are unlikely to help the drought.
“It will help a little but to be honest really, it’s almost the wrong sort of rain. What we’re likely to see is some heavy, intense downpours,” he said.
“With the ground baked so dry, it’s very difficult for the ground to actually absorb the water very quickly.”