Friday, 4 July 2014

Using large pipes as rainwater storage

In this interconnected age, whenever you have a great idea and start googling it, you usually find that somebody else has had the same one. In fact, you often find that somewhere there is a lively forum dedicated to implementing that idea, with five-star experts who have been sharing their experience since before the internet was invented.

So when you do have an idea and can't find anyone else who has done it, you start to wonder whether you are just being stupid, and have missed something very obvious that will stop it from working.
For the water storage system, I've been thinking about using pipes, around 15 or 20 cm in diameter, and looking for inspiration and advice on my pan-pipe design, which I think will look a lot nicer than the horizontal pipe rainwater storage system. Either way, I can't find anyone else who has tried it. At least if they have, they haven't blogged, written a book or made a website about it, so it doesn't count.

The closest I can find is the Green Building in Louiseville, Kentucky, which looks to have spiral pipes for rainwater collection.

Then I actually talked to someone about it.

"Wouldn't they be really expensive?" Oli asked. He had laid some pipe before and was shocked by the price he had been charged. I wondered whether that was a supply chain issue, but looking on the internet for white pvc pipes, as thick as possible, the best I could find was 11,130 for 4m lengths of 150mm VU pipe from They also had VP, which was a little more expensive. I think the difference is in the wall thickness, 11mm vs 20mm, and there's more information here if you're really interested.

Each 4m length would hold about 70 litres, so the tanks alone would price the system above commercially available ones.

There is a good site recommending low-cost solutions here. But most of them are also low-beauty.