The group responsible for running the pool says there is not enough time or money to get it ready to open this year.
A survey by Portsmouth City Council revealed structural problems with the pool, including problems with the pipework.
Jane Smit
h, chairwoman of the Hilsea Lido Pool for the People group, said: 'These things take time.
'We had thought about opening the main pool but there is so much work still to be done and that is needed.
'We have decided that we didn't have enough time or money.'
As reported in The News, the group was set up with the intention of saving the pool from closure.
Council leaders handed over responsibility for the running of the main pool to the group last year.
They hoped to have it open ready for this summer.
But the group still has to jump through legal hoops before becoming a registered charity.
Only then can it work in earnest to raise the money needed to pay for repairs and refurbishment of the pool.
Ms Smith added: 'We are still wanting to become a registered charity and that is coming along very well and we are a now a company limited by guarantee which means we can trade but not for profit.'
The group plans on asking local businesses to help out with work on the pool once they have established the full extent of what needs to be done.
They also intend to apply for grants and loans from funded groups.
In the meantime the splashpool, which is still in the control of the city council, will be open this summer as usual.
Hilsea ward councillor Donna Jones said: 'The Hilsea Lido Pool for the People group has been working really hard to get the pool up and running.
'I've been working closely with them, and I am delighted that progress is being made.'
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