Martha's story: 'I love swimming and I am really looking forward to being the first person ever to officially swim through all the UK canal tunnels over one mile long. I'm starting with the Braunston Tunnel near Northampton. It's over 200 years old and is about 1,800 metres long.   

I recently went with my family on a boat trip through the Standedge Tunnel in West Yorkshire and really enjoyed it and that gave me the idea about swimming through tunnels. I was really surprised when the Canal and River Trust gave me permission to do this. They've been really helpful and are providing a boat to guide me and lots of support. All the money I raise will be shared between them and Wateraid.

The swim will be a real challenge for me. I'm excited and nervous. 

I've been practising over the summer at Jesus Green lido, the River Cam in Cambridge and also with my uncle Dan in the sea at Bosham.'

Donating through JustGiving is simple, fast and totally secure. Your details are safe with JustGiving – they’ll never sell them on or send unwanted emails. Once you donate, they’ll send your money directly to the charity and make sure Gift Aid is reclaimed on every eligible donation by a UK taxpayer. So it’s the most efficient way to donate - I raise more, whilst saving time and cutting costs for the charity.

So please dig deep and donate now.