At Glastonbury, the Green Police are no more. They have been relieved of their duties to stop people littering and peeing on the ground by Gaia's Guardians, a 200-strong group of like-minded and committed stewards, singers, media people, water scientists, toilet enthusiasts, photographers and film-makers, all who revere the Goddess Gaia.

The idea of the Green Police was gentle humiliation. When they caught someone dropping a fag butt or peeing where they shouldn't, they would blow their whistles and make a spectacle of the offender. But this superficial approach was not creating long-term behaviour change, and the mess after each Glastonbury was the same or more, as consumer-lifestyle-driven revellers brought cheap imported tat, equipment and tents and left them onsite for someone else to clear up.

The environmental implications of having so many people together in one rural location are considerable. In their thousands, revellers who pee on the ground pollute the water table. The ground water runs into the central Whitelake River and down the valley, affecting wildlife and fish for miles around. During the festival, the Environment Agency tests the water regularly, and has the power to close down the site if too many people have urinated and polluted the site. Plastic litter, tent pegs and general waste takes its obvious toll on wildlife and farm animals, and each cigarette butt can contaminate 8 litres of ground water when it's dropped on the soil, taking up to 14 years to degrade.

Bernadette Vallely, who ran the Green Police for 10 years, was asked by Glastonbury's Liz Eliot to propose a new way of looking at an old problem. Bernadette said, "At the same time I was personally on my own journey of observing Earth Goddesses and thought Earth Goddesses could be the theme - hence the name Gaia's Guardians - Gaia's Guardians as guardians and stewards of the festival and the Earth.

She understood that by connecting people to the Earth as a living being would bring them some level of responsibility and connection to Mother Earth. "I wanted to explore new ways, perhaps more subtle ways and hence the choir was born."

Bernadette sifted through 50 applicants for the position of Musical Director and one person shone above all the others: Susie Ro Prater, already a gifted group singing leader, who worked at the Unicorn Voice Camp teaching other choir leaders. Susie formed and directed Shakti Sings, a national choir which became the major part of Gaia's Guardians.

Members of the choir dressed in red, looked beautiful and sang lilting lullabies and deep spiritual soul music to awaken that part in people that feels good when we nurture and do no harm. Singing had penetrated their awareness, and hearts. Revellers came up with a nickname, "the red people", and were curious about their message.

Singing was the core of Gaia's Guardians' operation, but the media team widened the message on social media to be picked up by revellers, and by getting more widespread coverage on national media. Film-maker Mark Whitely made several short films which were shown on the large screens at the Pyramid Stage between bands. These ads, which appealed to festival-goers' better nature, were seen by 100,000 people.

The culture shift was on.

One of the main tools the choir used to stop littering was The Pledge. They asked people to touch the Earth with their left hand, and say "I pledge to love the farm and do no harm." People went nuts over this, cheering and feeling good, and walking away with behaviour changed.

Bernadette said, "Touching the Earth is a conscious decision. Connecting and allowing the Earth to connect with us started a conversation of subtle, delicate, powerful connection. Psychically people connected on an Earth level. And I realised many, many people go about their ordinary lives and never touch the Earth - they go to their offices in trains and cars - it was fresh and new to ask young people to bend down and connect with Her and touch Her. For a lot of people that would've been a novel experience."

And yes, it worked. Dulcie, a Glastonbury litter picker for many years, said the area around the Pyramid Stage was the cleanest she had ever seen it. People had started to take personal responsibility because they pledged not to do harm, and because gentle, deep singing had penetrated their awareness.

A week after the festival, the good weather meant the site was already looking amazing. Litter pickers were 10 times faster than normal. Because the site was so clean so quickly, Michael Eavis was able to donate the unused clean-up costs, a hefty £1.25 million, to Oxfam, Greenpeace and Wateraid.

Bernadette said, "Some of that is definitely down to Gaia's Guardians, helping to get the message across and helping people love the farm and do no harm with such joy and love. Overall, the Gaia's Guardians were fantastic, and very well received. We invoked the spirit of Glastonbury in an inspirational way."

Shakti Singer Zoe Thomas said, "I just had the best time at Glastonbury and I know our message touched at least a few. On the outskirts of Mumford and Sons, Kate and I were spotted as two of the Red People and were told how much our singing had been enjoyed and how one admiring lovely couple had not thrown anything on the ground since! I am sure this filtered through to many, many more."

And singer Bharati Pardhy added, "A friend of mine admitted to peeing on the ground early on when we met up on site. He subsequently took 'the pledge' and then after the festival he said, when asked, that he hadn't done it again. Result!"

Bernadette said the Environment Agency reported a lower level of urine in the water around the site. She added, "The truth is that litter picking is always easier when it doesn't rain so I'm not claiming it's better. But the site was much cleaner than in previous years."

So the Glastonbury litter culture is being addressed through people taking personal responsibility and not bowing to humiliation. 2013's cleaner site may be the first year on the road to a future festival which is perfectly clean at the beginning and at the end.

Bernadette concluded, "We understand we have some way to go. We are moving people from ego to eco, on an individual level. We'll be back next year, even better. People can join Shakti Sings. It's a national choir."

Julia Lockwood is Press Officer for Gaia's Guardians