The Temporary Use Ban will come into force at 12.01am on Tuesday, August 18, and will prevent household customers from using hosepipes for a range of non-essential activities.
These include watering gardens, lawns, flowers and plants; washing private vehicles; cleaning windows, patios, paths, and driveways; filling or maintaining paddling and swimming pools; and filling ornamental ponds and fountains.
It supplies most of Dorset, including communities around Dorchester, Weymouth, Portland, Bridport, Sherborne, Blandford Forum, Gillingham, Shaftesbury and much of the county’s rural hinterland
The company said demand for water had remained at record levels for more than 40 days amid heatwaves, a lack of significant rainfall, and forecasts showing continued dry conditions.
The water provider said customers have been using more than 400 million litres of water a day – 30 per cent above the normal level for this time of year.
Its highest daily demand of 2026 came on July 11, when 449 million litres were used.
Chief executive Ruth Jefferson said the decision had not been taken lightly.
She said: “After 50 years without a hosepipe ban in the Wessex Water region – the first since the famous drought of 1976 – this isn’t a decision we’ve made lightly and we’re sorry for the inconvenience it will cause.
“We know so many of our customers have already been taking steps to save water and we’re incredibly grateful for their support so far this summer.
“It makes such a difference.
“But the prolonged and extreme dry weather has meant demand across our region has consistently remained at more than 400 million litres per day, 30 per cent above average for this time of year and the equivalent of almost half a million hosepipes running for a full hour every day.”
Mrs Jefferson said Wessex Water was not running out of water for essential use, but said the scale of demand was making it more difficult to transfer water through the network and replenish underground treated-water storage reservoirs.
The company said it had increased its leak detection and repair work over the summer, with find-and-fix rates up by more than a third in the past month.
It said leakage across its region had fallen by 60 per cent over the past 30 years.
The water provider is also contacting larger business customers who use high volumes of water to urge them to avoid non-essential use.
Some exemptions apply, including for customers unable to make reasonable adjustments because of a disability or health condition, as well as for animal welfare, health and safety, and certain business activities.
A hosepipe ban has already been issued for South West Water which operates parts of Dorset near Lyme Regis. This has been in effect since August 8.