I have a largish vegetable plot, and have recently put in new surface water drainage for the house, directing the water into a ditch nearby. I have a series of water butts in the vegetable patch which can all be kept at the same level using syphons, so I only need to supply water to one of them. The water in the ditch is much lower than the water buts and so I want to rig up a mechanism to raise it up to the required level. There are a numnber of approaches I could take, but I want something that is low maintenance, preferably something I could make myself, something that doesn't need to be plugged into the mains, and that will only try to pump when there is water there to be pumped.

I had idly wondered if I could rig up something water powered (bearing in mind that the only water in the ditch is what runs off my roof about 30m away, and therefore not likely to generate much power) - perhaps a screw thread in an angled pipe to feed a small header tank at the right height for the butts.

Anyone know of a design that might do the job please?

I'd need to raise it about a couple of metres I think. I did consider a solar powered pump, but wasn't sure how practical that was - are small pvs 12V? Are there any compatible water pumps? The non-pump electrics would have to be sufficiently moisture sealed, and presumably you'd need a battery as well (otherwise it wouldn't pump at night).

I know it's a bit Heath Robinson, but I still wonder it there's an entirely mechanical solution...

Sounds like a good approach. Have you any possible PV panels in mind? What about filtering the water?

I could do that (run water into a butt near the house and then a hose to the vegetable patch), but as I've just expended a huge amount of effort putting in the drains to take the water away from the house, the idea doesn't appeal, even though it would be simple. There will still be water butts by the house, and any one of them could be used for the purpose you describe, but it would mean having a hose pipe running a considerable distance, including over paths where aging relatives would be sure to trip over them, cars would drive over them, etc.

I like the solar powered marine pump idea though. I expect it would work out quite expensive (all things marine tend to be I understand)?

I like your thinking - perhaps an ornamental fountain that doubles as a sprinkler?

On a more serious note, I believe that the ifrst house in the country to have electricity used a small hydroelectric plant. Water power was also used to drive a pump on exactly your principle - a large mass of water falling a small distance used to pump a smaller volume of water half way up a hillside. On a drastically smaller scale, I had hoped to do the same.

Excellent and very much 'in keeping' with veg plot design ie doable from reused bits and bobs + hours of fun getting it to work. I see the 'weir' having a dual use dunking watering cans instead of waiting for them to fill from the water butt taps.

Yes Joe, I can't deny it - I'll probably end up running a hose pipe down the inside of the new drains I've put in so that it's protected and out of site. I still like the idea of a pump though, and will look into everyone's suggestions (thanks Paul_B)

Greenman.

Take a look at spiral water wheel pump on youtube. Fantastic.

Is it the technoprat one in the banana plantation we are supposed to be looking at?

I suppose it's (the banana plantation one) really just a modified form of the archimedes screw, which is what I had envisaged would possibly work for my application.

I was thinking I could put a suitable screw inside a plastic 30mm waste pipe, tilt it at an angle so that the pitch of the thread prevents the water running back, and then using the flow of the water to drive it. It would only run when rain water flows, but then there would be no point in it running the rest of the time! The main difficulty is how to source or make the screw...

Another aproach (and probably more effective) would be to put the thread on the inside of the pipe, and to rotate the pipe instead. This would have the advantages of there being fewer moving parts, and not having to engineer the screw to fine tolerances to create an adequate seal. Again though, making the screw thread would be tricky, and attaching it to the tube too for that matter...

Any suggestions anyone?

Thinking outside the box a little - why don't you just erect a small shed near your water butts and use the run off from that?