Capital pee: Amsterdam festival puts visitor urine to good use

Summer festivals: for most of us they spell rain, mud, dodgy takeaways, grungy portable toilets and worse. But the organisers of this year’s Sail Amsterdam are determined we’ll never see them in such a negative light again – once we realise how much urine they generate.

Generating urine is a good thing, say environmentalists, because it contains phosphates – particularly one called struvite or magnesium ammonium phosphate – which helps crops to grow more quickly in a world in which food security is an international priority.

That’s the good news. The bad news is that where phosphates are not generated naturally, they’re usually produced by mining, particularly in Africa and the Middle East – amid warnings that the world’s dwindling supply may not last much more than another 300 years.

That’s why Sail Amsterdam – the world’s largest free nautical festival, featuring more than 600 tall ships – plans to ask male visitors to the Dutch capital next week to pee in special locations, so that their urine can be “harvested” and turned into fertiliser.

Working with the city council, they aim to collect as much as 100,000 litres of urine during the five-day festival – giving “donors” the opportunity to vote for one of three green projects they believe should get the benefit of this veritable wave of environmental wellbeing.

“Phosphates are in short supply, and that’s why we are trying to show people that human waste need not be treated as rubbish,” said the festival’s spokeswoman, Danielle van Gerven.

Smoothly anticipating the next obvious question, Ms Van Gerven added that male donors were being targeted because it was “easier to collect uncontaminated urine from them”.

Producing fertiliser from urine is an idea whose time has come, it seems – and the Netherlands is determined to be at the forefront of this agricultural revolution.

Already, urine produced by some 600 civil servants at one go-ahead local authority headquarters in Assen, in the northeast of the country, is collected in special tanks and used as organic fertiliser by its parks department.

Urine is usually sterile when it leaves the body, and surveys in Sweden have shown that an average northern European adult pees enough plant nutrients to grow 50 per cent or more of the food he needs to sustain himself.

But while that may be convincing on paper, the problem, inevitably, is the “yuk!” factor.

Which is why the future for urine looks more likely, for the moment, to be golf courses and football pitches – producing their own turbo-charged local fertiliser courtesy of their own members and fans, and all with a minimum carbon footprint.