Yorkshire Water has urged visitors to its reservoirs not to swim in the water as the weather warms up.
The warning comes after several tragic water-related incidents in the UK. It also comes after an increase in reports of people entering reservoirs.
Anyone who does see someone in the water in need of help should call 999 and ask for the fire service immediately.
Gaynor Craigie, head of land and property at Yorkshire Water, said:
“As the weather warms up it is important visitors to our reservoirs are not tempted to get into the water to cool off.
“Low water temperatures can cause cold water shock that may lead to hyperventilation, increased blood pressure, breathing difficulties and ultimately death.
“Underwater machinery and the currents associated with their operation are also a potential hazard for people choosing to enter the water.”
A man who fell out of a canoe in the River Ure at West Tanfield, near Ripon, died on May 21. A second man in the canoe managed to get out of the water and went to hospital.
A 13-year-old boy drowned in the River Calder at Brighouse, West Yorkshire yesterday.