searching the brown banks of the river thames. ifound a complete iron age pot, a tudor shoe. but alongside the treasures are more familiar items that have been flushed away. condoms, tampax applicators, sanitary towels, wet wipes. you name it, i ve found it. we are spoiling it, you know? we are pouring our waste into it and just destroying it. but deep beneath the river, the clean up plan is nearly ready to flow. a £5 billion tunnel, the largest and deepest the capital has ever seen. the reason we are riding on bikes through this tunnel is because it sjust so big it s 15 miles long, all the way across london, under the river thames. and the idea behind it is, well, that it will collect the sewage and storm water that at the moment goes into the river, and take it downhill to east london where it can
discharged raw sewage into the river thames after heavy rain. but that could be about to change, thanks to a vast tunnel that s been built underneath the river seven metres wide and 25km long. our environment correspondent jonah fisher was given a rare opportunity to ride a bike along the tunnel before it fills up with sewage. just looking for history. looking for stories, really. lara is a mudlark, forever searching the brown banks of the river thames. ifound a complete iron age pot, a tudor shoe. but alongside the treasures are more familiar items that have been flushed away. condoms, tampax applicators, sanitary towels, wet wipes. we are spoiling it, you know? we are pouring our waste into it and just destroying it. but deep beneath the river, the clean up plan is nearly ready to flow. a £5 billion tunnel, the largest and deepest the capital has ever seen.