All life on earth relies on our rivers and lakes.


1992: (25km): 9 hrs 52 mins

When people think ‘most dangerous animal in Africa’ they usually think lion or leopard or snake. But it’s actually hippos and crocodiles. Hippos kill more people each year than any animal (after mosquitoes), and Lake Malawi has plenty of them.

They were all I was thinking about for the first 200m of this swim. I just wanted to get out into the safety of the deep water, so I kept my head down and focussed on speed. I didn’t even take a breath, let alone look where I was going.

Until I heard a shout from the support boat: my right arm is much stronger than my left, so I had swum a full circle and was still splashing around in the shallows! The pilot of the boat must have thought I was crazy…

The local people certainly did. No one had ever tried to swim across the lake before. We made it – but our equipment didn’t. The night before the swim all our gear was stolen – including sunscreen. Luckily I’d slept in my swimming costume, but I got really badly burned. Now I keep my essential swimming equipment with me at all times.


World Winter Swimming Championships, Finland

2006: Oulo Finland (500m)

Finland has the World Wife Carrying Championships, the World Air Guitar Championships, the World Mobile (phone) Throwing Championships … and the World Winter Swimming Championships, to which I was invited.

I arrived to minus 17°C and men with chainsaws cutting the top layer off the frozen Oulu River estuary to form a 25m temporary pool. There were swimmers from Finland, Sweden, Germany, Australia, Great Britain and Ireland. But I headed straight for the Russian cold-water swimmer Colonel Vladimir Lutov and challenged him to a 2km swim.

The press billed it as the Real Cold War, and the Colonel nominated two younger Russians to swim against me over 500m. I beat Alexander Brylin by 100m, and came in 150m ahead of Vladimir Nefatov (to be fair, both were swimming breaststroke). But the real victory was finding such camaraderie. When we three got out of the pool we shared a huge bear hug. Alexander and I traded swimming caps, dropped our bravado, and became firm friends. After all, when you’re only wearing a swimming costume there is simply nowhere to hide any animosity.



2006: (350kms): 21 days

When I dropped a stick into the water at the source of the Thames to test its flow, I couldn’t imagine that it would be dry seven weeks later. But when I arrived to begin my 350km swim of the River Thames from source to sea, there was no water whatsoever. I had to run 40kms in blistering heat before I found enough to swim in.

I thought it would take 10 days to reach the North Sea. It took twenty-one. I should have planned better. It was the worst drought in living memory, and the river was sluggish and often polluted. I got sick, repeatedly. The supporters along the way were amazing, but in London the harbourmaster wanted to throw me in jail. Still, the Prime Minister invited me to Number 10 to discuss the country’s carbon emissions, and the UK enacted the Climate Change Act soon afterwards.


Mt Everest, Nepal

2010: 22 mins 51 secs

I had resolved never to do another cold-water swim, but the Himalayas changed my mind. Glaciers are not just ice: they are a water lifeline for over 2 billion people, and if they melt away as scientists predict, the Himalayas will become the earth’s next big battle ground.

My kilometre swim across Lake Pumori, at 5,200m on Mt Everest, would draw attention to this issue. I took twenty-eight yaks and a speedo up the mountain, but I hadn’t factored in the radical tactical shift I would need to complete the swim.

Swimming at speed was not going to work at high altitude. Instead of minimising my time in the icy water and getting through the distance as quickly as possible, I was going to have to slow down. (Easier said than done in 2°C water.) This swim taught me that just because something has worked in the past, that doesn’t mean it will necessarily work in the future. I hope the world’s leaders are listening.

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