Approximately a third of England’s public leisure centres will remain closed on Saturday as a widespread picture of financial distress among community leisure operators overshadows the long-awaited reopening of gyms and indoor swimming pools.

While privately owned chains such as PureGym, David Lloyd and Virgin Active are eager to proceed with opening plans, the charitable trusts behind the country’s 2,116 council-owned sites, are being circumspect as coronavirus restrictions tip their finances into the red.

Jane Parish, the chief executive of Sencio, which runs three leisure centres and a golf course in Kent, said the future of its facilities was hanging in the balance after it ran out of cash during the quarantine period.

“We’ve been losing £100,000 a week of income but have still been incurring costs maintaining our buildings,” she said. “We’ve got no reserves left whatsoever.”

Parish said the need to limit visitor numbers meant Sencio would be making a loss when it opens its centres on 3 August.

Sencio has 11,500 members but its gyms and pools are popular with over-70s, some of whom were reluctant to return yet. It will take until early 2021 for income to reach even two-thirds of pre-pandemic levels, she predicts and is applying for a £700,000 emergency loan to tide it over.

“We applied for a business interruption loan with our bank but didn’t get it because they wanted security, which our council wouldn’t give us,” said Parish. “I employ 343 staff. That’s a lot of staff and livelihoods could be in jeopardy.”

She said “we won’t survive” if the loan request was later declined.

The UK has about 7,200 gyms and leisure centres, with approximately two-thirds run privately and the rest by councils or operators on their behalf.

Before the pandemic 10.4 million people had memberships but some of the large chains have reported losing up to a fifth of their clientele as Britons reined in spending during lockdown.

After a frustrating delay – gyms had hoped to reopen alongside England’s pubs and hotels – popular chains such as PureGym, David Lloyd and Virgin Active are champing at the bit despite the financial implications of half empty gyms, smaller exercise classes and expensive cleaning regimes. A date is yet to be set for gyms, leisure centres and swimming pools in Scotland and Wales to open, while facilities in Northern Ireland were allowed to open on 10 July.

The sports minister, Nigel Huddleston, said: “Given the huge benefits exercise has for physical and mental health, I know people across the country can’t wait to get back to the gym.

“But it’s vital that users feel safe. That’s why we have worked hard with the sector to make sure they have the guidance they need to put strict safety measures in place.”

Glenn Earlam, the chief executive of the David Lloyd chain, said he was hopeful gym usage would return to normal by the end of the year. The firm has lost about 10% of its 600,000 members mainly because it has been unable to offset the usual rate of attrition.

“Fitness is a successful growth business but this has been an enormous shock,” Earlam said. “We have survived four months of closure and we will be fine, providing people come back come back in normal numbers, even if it takes us a while to build back the volume we have lost.”

The shift to working from home is also creating opportunities for the upmarket chain, with its spacious centres and free wifi. Several companies have inquired about corporate memberships whereby staff could base themselves at a David Lloyd club.

However, there is a concern that nearly half of Britain’s public leisure centres will not be able to stay the course, meaning even those that open their doors in the coming days could be forced to close again.

UK Active and Community Leisure UK, the industry trade bodies, estimate 1,300 of the 2,727 leisure centres funded by local authorities and 20% of the UK’s swimming pools could go under by Christmas unless the government steps in to help.

“We have acute cashflow issues and are totally and utterly dependent on support from a council facing its own challenges,” said Chris Rushton, the chief executive of Active Tameside, which runs eight leisure centres in Greater Manchester. “We will open on a vastly restricted capacity and lose money as the furlough scheme winds down.”

Rushton added: “Swathes of our sector are at risk. Not everything will reopen, and not everything that opens will be the same as it was previously. We are a sector that is delivering untold health and social impact and that is what is in danger here.”