The timed 5km runs - which till now have been free - are held in Little Stoke Park near Bristol every weekend, with around 300 runners attending. They are billed as a way of getting everyone in the community to feel comfortable exercising, by removing barriers to participating in physical activity, including any sort of charge for participation.
However the Stoke Gifford Parish Council has now decided to introduce a charge for adult Parkrunners to contribute to the park's upkeep, particularly the paths which face "wear and tear" from joggers. It is believed to be the first council in the world to introduce a charge for Parkruns.
Parkrun organisers have warned the new charge will undermine the principles on which Parkrun is based and deter the people who most need the exercise from attending.
The news has sparked outrage across the UK, with nearly 50,000 people calling for the council's decision to be reversed. This weekend's Parkrun at Little Stoke has been cancelled amid fears that too many people will turn up in support of the event.
Dave Morris, London chair of the National Federation of Parks and Green Spaces, said the federation is "greatly heartened" by the national outpouring of solidarity with Parkrunners, but pointed out the real issue was to do with ongoing lack of funding for parks.
"Local councils are getting desperate due to the Government's continuing savage cuts to all public services, which threaten the survival of 'non-statutory' but essential provision like youth services, libraries and parks."
This state of affairs is "unacceptable" in a rich society, he added.
"This scandalous underfunding crisis must be reversed. We are calling for a National Inquiry into the funding for UK's parks and for their statutory recognition. As the voice of the movement of over 5,000 Friends of Parks Groups we are also calling on all park users everywhere to join their local Friends Groups and set up thousands more to fight for adequate funding, much-needed improvements and proper protection."
Little Stoke Park has hosted the events for the last three years, with around 300 runners each week. The council says the event has increased wear on the path and it is now facing a £60,000 repair bill, which Parkrunners should contribute to.
It argues that unlimited numbers of runners can attend the events, and that they "monopolise" the park paths and car parks for two hours each Saturday and Sunday, as well as using toilets, washing facilities and council storage space. Residents have also reportedly complained about runners parking on pavements and grass verges, and other "incidents involving runners" during events.
The council also says many of the runners come from outside Stoke Gifford and do not pay taxes towards the park's upkeep.
The Little Stoke Parkrun team has been fighting the plans for a year. Parkrun founder Paul Sinton-Hewitt said in a letter to supporters that the group was "extremely disappointed" with the council's decision. Legal avenues to challenge the decision are now being investigated.
Tom Williams, chief operating officer for Parkrun, said: "As we look towards opening our 1,000th location later this year it is clear that a per-event or per-runner charge simply would not be sustainable and would threaten our free-to-participate ethos. By agreeing to a charge in relation to use of the land at Little Stoke Park we would be establishing a precedent that would put the future of parkrun at risk."
The group pointed out that Parkrun was recently described as "a new model for community sport volunteering" in the Department of Culture, Media and Sport's Sporting Future paper. And it says it has been proven that charging participants a fee creates a significant barrier to entry, particularly amongst those who are currently inactive.
Williams said: "Parkrun has successfully moved nearly 60,000 previously inactive people into regular healthy activity. The key to this success has been a focus on removing barriers to event delivery as much as barriers to participation."
Graham Evans MP, chair of the All Party Parliamentary Group for Running, said: "Parkruns provide an invaluable way of utilising public spaces and getting the whole community involved – young and old – in physical activity, which we all know is massively important for our health and wellbeing.
"I have written to this Parish Council with some suggestions of how they may like to fundraise towards the maintenance of the park if they have found that the costs are above and beyond that raised by council tax contributions."
Neil Gray, SNP MP for Airdrie & Shotts, said the decision was "incredibly shortsighted and disappointing", adding: "I hope Stoke Gifford Parish Council will reverse its decision and no other local authorities will follow its poor example."