Wessex Water is reminding people not to visit its community sites and reservoirs during the warm weather, which have been closed to help prevent the spread of coronavirus.
The company said it is especially concerned about reports of people meeting up against all current advice and even swimming in reservoirs, which is not permitted at any time.
Philip Timings, Wessex Water’s Community Site Visitors Manager, said: “While our reservoirs might look inviting, especially during the warm weather, they are used for supplying water to our customers and have automatic equipment under the surface which can operate without warning and cause strong currents.
“The reservoirs are in remote locations and the water is colder and deeper than it looks, heightening the risk of cold water shock that can be catastrophic for even confident swimmers.
“So there are plenty of reasons why swimming is dangerous and strictly prohibited.”
Wessex Water closed public access to its reservoirs and fisheries last month in response to the COVID-19 outbreak.
While public rights of way remain, anyone using them is asked to do so in line with government advice on social distancing and not to stray on to the permissive paths which are closed.