The report Park Land, published today, outlines the state of parks cuts across the country with councils in the north east cutting deepest by almost 40 per cent over three years.
The think tank is urging the Government to establish a freely-available national and online urban green space map for the UK.
This would crowd-source information from organisations such as councils and charities as well as the public.
People would be able to use their smart phones to upload pictures of graffiti, vandalism, dog fouling and disrepair. They would also be able to compare ratings with other parks, access information on opening times, facilities and events.
According to Policy Exchange the map would encourage existing and new volunteer and community groups to improve the quality of their parks when councils or others have failed to act. It would also ensure that public money was being well spent and that clever innovations in improving green spaces could be shared.
The report found that current available green space maps are woefully inadequate. It says the City of Westminster, for example, underestimates the amount of urban green space in its borough by around 40 per cent.
One successful project is the Love Lewisham app which allowed the public to photograph graffiti or fly-tipping and report it to the council. Within two years the number of complaints about graffiti had fallen by almost a third.
Report author Katherine Drayson, said, "Flourishing parks and green spaces are central to the success of our cities. They are places to exercise, to socialise and to relax. They also support our wildlife, clean our air, reduce flooding and even cool our cities down. Yet we’ve all gone for a walk in our local park only to find used needles, dog excrement and litter ruining our beautiful green spaces.
"A ‘Markmypark’ website would allow the public and councils to work together to tackle much of the anti-social behaviour that blights our parks."
Commenting on the report, parks champion, The Parks Alliance, which was set up by 40 key executives from across the public parks sector said: "We hope that policy makers and those that fund public services will read and respond to the report and help turn this proposal into a reality. By supporting the report's idea of mapping the quality of parks, local parks users can add their voice to the debate about the long term funding of parks across the UK."