South West Water say they will give £30 credit to customers in Cornwall if Colliford Reservoir reaches 30 percent capacity by 31 December.
The company has made the announcement this morning (11 November) to try to encourage residents to limit their water usage.
It follows what they call unprecedented demand for water, alongside exceptionally hot and dry weather.
Customers can check reservoir levels on South West Water’s website. Levels are currently below 20 percent.
If Colliford Reservoir reaches 30 percent full, the company says all household customers in Cornwall will receive a £30 credit on their accounts which will show on their next bill after the incentive ends.
The water company fix up to 2,500 leaks a month, say say they are finding and fixing more leaks than ever before.
Earlier this year Colliford Reservoir, which serves around 255,000 households in Cornwall, fell to its lowers ever recorded level.
South West Water are continuing to urge people to reduce the amount of water they use to help recharge the county's river and reservoirs. They say this will ensure there is enough water for next year.
Laura Flowerdew, Chief Customer and Digital Officer, said: “We have been working around the clock to bring new supplies safely online, find and fix more leaks than ever before and help businesses and customers reduce their water usage.
"These proactive steps have helped river and reservoir levels stabilise across our region and recover in Devon.
"However, in Cornwall reservoir levels remain low. That is why we are asking everyone to help Stop The Drop so we can restore reservoir reserves, ensuring we have enough water today and into next year.
"Our Stop The Drop campaign draws on the collective might of the people of Cornwall who can help by reducing their water usage to secure supplies in Colliford Reservoir. Every one drop saved protects the water we need now.”
South West Water said they had one of the lowest rates of leakage across the industry.
A spokesperson said: "In 2021/22 we improved our leakage performance by 6%, reducing leaks to 116.7ml/d.
"We have targets to further reduce leakage by 15% from 2020 and are currently on track to do so.
"With around 30% of leaks now typically found on customers’ own properties, we have extended our offer to fix these leaks for free – saving enough water to date to serve the equivalent of 8,000 homes."
South West Water say if everyone in Cornwall cut their shower time by just 1 minute it would save more than 4.5 million litres a day.
They warned that day to day activities around the house can use a lot of water, 50 litres per washing machine cycle and 14 litres for a dishwasher cycle.