Young people are being urged to stay safe near open water.
Lancashire police and fire chiefs have issued the joint call with reservoir and quarry owners United Utilities and the Mineral Products Association.
It comes after the drowning of Chorley teenager Thomas Barton at Yarrow Country Park last Sunday.
PCSO Michelle Appleton said: “I’d urge people – please avoid quarries and large water areas.
“Although the water looks warm, in reality the temperature is very cold and this can dramatically affect your ability to swim.
“We have lost two teenage boys in the last 12 months and do not want any other parents to suffer this terrible loss.”
Thomas, 15, was with four friends at Birkacre Lodge, in Yarrow Valley Country Park, near Chorley.
The Holy Cross High School pupil had gone under water while swimming in the lodge.
The fire service were called after his friends became alarmed when he did not resurface.
The other youngsters were stranded on a floating jetty in the middle of the lodge.
Police, fire and ambulance services attended, and the crews went into the water to search, but did not find him alive. Thomas’ body was recovered at 11.10pm and retrieved by the police under-water
His friends were rescued by the Bowland Pennine Mountain Rescue Team.
Phil Cox, of Lancashire Fire Service, said swimming in rivers, ponds and lakes was ‘extremely hazardous’.
He said: “Underwater currents and the shock of the cold water can mean that even strong, accomplished swimmers can get into difficulty, so our advice is simple – don’t be tempted to take the risk.”
Thomas is survived by his parents Simon and Clare Barton, sister Rachel, 19, and brothers Matthew, 24, and Robert, 23.