The city council is considering introducing new rules for parks which have come in for a storm of criticism.
Complaints to date include the proposal to restrict cyclists to 5mph, to charge groups which use parks and to force owners to keep dogs on a short lead.
George Parsonage, lifeboat officer for the Glasgow Humane Society, has now raised concerns about allowing children and adults to swim in city rivers and canals.
He says in a letter to the city council: "Glasgow Humane Society has been at the result end of persons swimming in waterways or playing on rafts on waterways, having to rescue many and to recover the bodies of many more drowning while swimming in said waterways.
"Indeed, the very first time my father took me with him on a case was when two boys were drowned off a raft at Bothwell, followed the next day by two boys drowned swimming at Motherwell."
Mr Parsonage, who has rescued more than 1500 people from the water in the past 50 years, stressed his comments are his own and not those of the Humane Society.
The new park rules, which are presently out for consultation, state: "Activities such as canoeing, rafting, rowing, sailing and swimming are allowed, except in ornamental ponds, fountains or in waterways specifically managed for horticulture or wildlife."
Mr Parsonage said: "I was informed the rules had been altered to encompass these words some years ago.
"But the reality is that noticeboards in our parks have the wording 'no person while in any park shall bathe or wade in any lake, loch, pond, pool, river, canal or stream except as may be designated for that purpose by the council.'
"Are we going to have the Humane Society, Fire and Rescue and the police watching children going into the Clyde swimming and nobody can do anything about it until one starts screaming for help by which time it could be too late.
"Will we have to watch that child drown or someone lose their life trying to rescue them?
"These rules are a mistake but I feel sure the council will rectify them."
A council spokesman said: "Current park management rules allow swimming in specific areas.
"The amended rules presently under consultation allow the same.
"Individual areas have signs warning against swimming where it could be potentially unsafe."