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Swimmers may have to arrive in their costumes and the number of people in lanes be limited when pools reopen, to allow for social distancing.
For the time being indoor and outdoor pools must remain shut, despite the easing of some lockdown restrictions,
It's thought chlorine in swimming pools will kill coronavirus but Swim England has warned a "stricter regime" will still be needed when they do reopen.
The body has warned 500 pools in England could close permanently.
Pools cannot reopen before 4 July under the government's current plan for lifting lockdown restrictions and the advice also says people should not swim at the beach without a lifeguard present.
But as the weather has warmed up, people have headed to beaches, with three people seriously injured while jumping off a cliff into the sea at Durdle Door in Dorset on Saturday.
In London, the Serpentine Lido in Hyde Park was forced to close after attempting to reopen last week because it became too crowded, while police also reported crowds at Ruislip Lido.
Chlorinated water should kill the virus, but preventing it from spreading in changing rooms and other areas around pools remains a concern.
Swim England chief executive Jane Nickerson said guidance was still being finalised but that people might be asked not to use changing rooms, and pools could be told to limit how many people could be in the water at a time.
She told The Times people might have to arrive "beach ready" in their costumes.
Olympic gold-medallist Duncan Goodhew, who is president of the Swimathon charity, told Radio 4's Today programme there were 5,000 public pools in England, 10% of which might not be able to reopen with social-distancing measures as they were "old, inefficient and expensive to run".
He said: "A little like a restaurant, it becomes very difficult economically to make it work because you're just not getting the volume of people through."
Swim England has called for financial support from the government to help ensure pools are financially viable as the lockdown eases.
Ms Nickerson said: "We know there will be major financial challenges for pool operators, all of whom saw their income disappear overnight, and who will be faced with the dilemma of opening pools against the backdrop of less footfall and increased environmental costs."
Mr Goodhew, who won gold at 100m breaststroke gold in Moscow in 1980, added: "It's really important the pools open because there are many, many people out there, some people who are disabled or have bad hips, etc, who cannot do any other exercise.
"From a point of view of quality of life, we've got to get them open."
Prof Keith Neal, emeritus professor of epidemiology of infectious diseases at the University of Nottingham, said chlorine was "very easily able to inactivate most viruses including Covid-19", but "the main problem will be the social distancing, mostly the changing rooms".
Swim England is working with Public Health England on advice for pools reopening, which will be published on 15 June.
Among the issues which will be covered are water treatment, air circulation and social distancing.
The Swimming Teachers' Association is also liaising with the government on measures for after the lockdown.
Chief executive Dave Candler said there was no "one-size fits all" answer to personal hygiene and social distancing measures for the industry - which would "most likely mean smaller classes in the interim".