By Joe Tidy, Sky News Reporter
Park users could be asked to pay for membership as part of proposals to fund green spaces in Britain.
It is just one proposal put forward by a report from the Heritage Lottery Fund which warns that the country's parks and green spaces are "on the edge of a precipice".
A £700m cash boost in the mid 1990s from lottery money has helped get parks in good health but the report says that councils are cutting budgets in order to cut costs.
Dame Jenny Abramsky, chair of Heritage Lottery Fund, says: "Parks are highly valued, precious places that are vital to our physical and emotional well-being. Following decades of decline, lottery funding sparked a parks renaissance but that is now at risk.
"We realise these are financially tough times and that is why we need collaborative action and a fresh approach to halt this threat of decline and stop this cycle of boom and bust.
"Our parks are far too important not to act now."
Almost half of UK councils are considering selling parks and green spaces As parks are a non-statutory service, their budgets are highly vulnerable.
A survey of more than 170 councils found that 86% of parks managers' report cuts to revenue budgets since 2010, a trend they expect to continue over the next three years.
Forty-five per cent of local authorities said they are considering either selling parks and green spaces or transferring their management to others.
As well as potentially charging park users for membership, other ways to bring in money are being suggested.
Around 34 million people use Britain's parks each year For example, money could be raised through sponsorship or advertising in parks, small-scale agricultural projects like bee-keeping could be set up, or park space could be hired out privately.
Speaking to Sky News, park users had mixed feelings about the ideas.
One said: "I pay enough in my council tax so I wouldn't want to pay more despite councils being squeezed."
Another park user said: "I wouldn't mind sponsorship or advertising as long as it wasn't over the top as I think it could take away the enjoyment of the park a bit."
The report points to a short-term impact on park users with 85% of managers intending to increase fees for parking or facilities in the next three years.
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