It’s unlikely anyone testing the water at Hampstead Heath’s many ponds expected their checks for bugs like E.coli would ever become part of a performance art project.

Ham & High: One of the binaural mics Catherine and Sarah used to produce the Fleet Footing project. Picture: Catherine KontzOne of the binaural mics Catherine and Sarah used to produce the Fleet Footing project. Picture: Catherine Kontz (Image: Archant)

But in the new Fleet Footing project by Catherine Kontz and Sarah Grange, the openly available data becomes just that.

Sarah and Catherine, long-time friends, have put together an immersive experience that invites users to follow the path of the historic hidden Fleet river under London.

Start at Hampstead Heath, where if you swim in the ponds you are technically swimming in the Fleet, and follow the trail all the way down to Blackfriars and you might just learn a little more about the city.

Sarah told the Ham&High: “It’s inviting the public to think a little bit differently about what’s around them – to look under their feet at the right times and see the ancient history of the Fleet. They will learn a little about Boudicca, and perhaps some Anglo-Saxon.”

The project’s idea is a simple one: download the soundtrack, put in headphones, then follow the maps along the Fleet. With headphones in you will be treated to a mixture of specifically composed music, spoken word, and instructions about how to interact with the world you uncover during the walk.

The project has launched as part of the Tete-a-Tete Opera festival, which both artists have been involved in for several years.

It also uses cutting-edge binaural recording technology which means that the sounds one hears during the tour seem to be coming from all different directions.

Sarah explained: “It makes for a really 360-degree experience. We recorded at some of the points on the walk and you can get a really fascinating feeling of being part of the world.”

As for why they used the results of water testing, Sarah said: “We took the data and created something that’s simply based on the water. There’s water throughout the music – we even recorded a clarinettist who improvised with water in the bell of their instrument.”

The project takes walkers from the Vale of Health, where the old Hatchett’s Bottom bog first fed the Fleet, past the ponds and through Kentish Town before it meets the Thames at Blackfriars. Search for “Fleet Footing” for the soundtrack.