gravity fed drip irrigation

Apologies if this topic has been thoroughly discussed in this forum. And apologies again as I am somewhat abusing this forum as my system is not a rainwater catchment one (well, it was at some point but currently I'm pumping water to it from a well using solar panels). But I do have a water tank that is 1000 liters on a small hill at the back of my garden. I think the height difference between the tank and the garden where I have my crops is at most 10 meters (hard to measure precisely). I've drip irrigation system using standard inline emitters. And it seems to work reasonably well (sort of, really).

But two things concern me: occasionally a bird or a rodent pecks a hole in one of the drip lines -- sometimes the main line. In this case, the already not so high pressure drops noticeably. If this happens before I notice it, the crops can get poorly watered (I live elsewhere and visit the site about once a week). If I had more pressure, most emitters would still work despite the leak from bird damage.

Secondly, I'm concerned that if I add more beds and use longer drip lines, the pressure may drop too much. So I've to be cautious about how much I plant and ensure that the current gravity pressure supports any new bed that I add.

Is there a solution to this problem? I do have solar panels in the site that allows me to pump water to the tank when the sun is high. But I do not have a battery or an inverter and I sincerely don't want to buy them. Can you recommend me a reliable solar pump that can draw water from my tank and pump it with pressure to my drip lines?

Or perhaps is there a better way of irrigation than drip lines? I've read somewhere that using a normal hose punched with dry wall screws could be a good option (screw stays inside). This could be a labor intensive process but perhaps it may help with the bird damage as the hoses are thicker (not sure about the rodents though).

I would greatly appreciate any suggestions.

10 metres of head is actually a reasonable amount of pressure for most drip emitters, they don't need a lot. Main thing I've found is keeping your main pipe diameter generous enough so friction losses don't eat into it before it gets to the emitters. What kind of emitters are you planning to use?

You can improve things by adding more outlets to the tank, so as to bring multiple hoses (as fat as possible) down to the garden.  In the garden itself, it will help to even out the distribution by having no dead-ends in your drip hoses, but rather have them loop back to the supply, even if by means of a simple "Y" connector.  Otherwise on long runs the emitters closest to the supply will get more and those at the far end less.

Ahmet,

Actually, nice job with a full 10 meters—that’s a decent water head to work with.

I used drip irrigation from Dripworks.com, and you might consider constant flow emitters as opposed to pressure compensating emitters.  the constant flow emitters will emit a very consistent flow over a given length (maybe 7 meters or so, I would have to check).  They can work from a very low head of just 1-2 meters and sometimes even less.

But at 10 meters you might be in the range for pressure compensating emitters which are very, very precise and can make some very long runs.

As far as critters pecking or chewing holes, I would think seriously about getting some solid pipe from the tank down to the ground—and then bury a bit underground.

Hope that helps,



Eric