Small reliable (low maintenance) irrigation system from pond?

IHDiesel73L · Jul 13, 2022

I'm on 2 acres with a small (75' x 150' give or take) pond in the back that is about 6' deep in the middle. Essentially its just a hole in the swamp that the previous owner dug about 50 years ago. He took his backhoe into a wet area and started digging and mounded up the spoils on the low side, put an 8" overflow pipe in and since the pond is well below the water table it stays full year round. In the five years I've lived here I've seen it drop maybe 2-3" below the rim of the overflow. In any event, my daughters have really gotten into vegetable gardening and I don't see any reason to run my well pump (which is probably on borrowed time as it is) to water the garden when I've got nearly a quarter million gallons just downhill from the garden. The pond is about 200' from the garden and there is probably about a 30' difference in elevation between them. I have a small building right next to the garden that I could pull power from/use to house a pump. My questions are as follows:

What kind of pump should I be looking at given the suction requirements?
How large of a line should I be using from the pond to the pump? (Would 1" black poly work, etc...?)
What kind of a strainer should I have on the end of the line? Obviously I don't want crud getting into the pump but I don't want to have to be constantly unclogging the inlet every time I want to water the garden either.
I live in the Northeast-what should I plan to do with everything in winter? Obviously the pump should be winterized and most of the suction line should be empty, but I'm figuring I can locate my strainer rig close to the bottom where it won't freeze?

I should add that I'm not in a part of the country where water rights are an issue. We are blessed with an overabundance of water such that I don't need permits or language in my deed permitting me to draw from my pond, etc...

mapper · Jul 13, 2022

Make a rainy well next to the pond. Dig a hole about 5-6' deep next to the pond put a 2'-3' perforated pipe vertically in the hole. Backfill around it with gravel. It will fill with water very quickly, if not connect it to the pond with a gravel filled ditch.
This will filter the water and give you a place to use either a submersible or shallow draft pump.

bcp · Jul 13, 2022

No pump will pull the water up 30 feet. It must be pushed.

Pump should be located at about halfway or more down to the pond.

Bruce

jaxs · Jul 13, 2022

The ONLY reason you should consider pulling water from the pond rather than the existing well is whether the well has a limited flow and might be pumped dry leaving house without water and that sounds unlikly with a 30' water table. You say the well pump is on borrowed time but a replacement is cheaper than a pump plus pipe,valves and other components to pull from the pond. Why are you not considering this route?

jaxs · Jul 13, 2022

bcp said:
No pump will pull the water up 30 feet. It must be pushed.

Pump should be located at about halfway or more down to the pond.

Bruce

I'm advocating irrigating from existing well but for benifit of our general knowledge bank why wouldn't a conventional deep well pump pull water from the pond? 30' of head seems easy considering how deep many wells are.

mapper · Jul 14, 2022

bcp said:
No pump will pull the water up 30 feet. It must be pushed.

Pump should be located at about halfway or more down to the pond.

Bruce

Theoretically you can lift water 33.9 feet at sea level. Your pump would need to pull a perfect vacuum to do so. Would also need a strong pipe to avoid collapsing it.
Much better to put the pump at the bottom and push the water uphill.

ning · Jul 14, 2022

jaxs said:
I'm advocating irrigating from existing well but for benifit of our general knowledge bank why wouldn't a conventional deep well pump pull water from the pond? 30' of head seems easy considering how deep many wells are.

Well pumps are at the bottom of the well, not at the top.

ning · Jul 14, 2022

My experience with gardening on pond water is that everything will clog rapidly because pond water is filthy, even when it looks clear.

You can get high-flow filters in black housings which reduce filter clogging due to algal growth but it's still going to grow in your lines, as is other sludge.

Our land has water from a nearby irrigation canal (very clean) which fills a cistern via gravity; the land was originally (before my time) set up to pump water to the pond if needed, and another pump took water from the pond and irrigated with it. This was a mess, clogs etc even with a filter (which needed nonstop attention), I now irrigate directly with our tank water (and still filter it but the filter barely needs any cleaning).

Well water would be even cleaner.

Definitely use the well if it's at all reasonable.

ehcrain · Jul 14, 2022

I used a gas powered waste pump to irrigate from a pond, it's a 3" line with a 20' suction line that has a strainer on the end. Had aluminum 3"pipe in 20' sections that were coupled together and vertical sprinklers on 1" uprights every 40'. I could usually run 6 to 9 sprinklers depending on how far up from the pond the line ran, the furthest point from the pump was about 400' with a 10' elevation increase. The secret to cleaner water was to keep the strainer off of the pond bottom, a 2 to 3 foot rope attached to a couple of gallon jugs worked well.

I foolishly sold the aluminum pipe and will be getting a new setup soon using flexible discharge hose and a single rain gun. The hard pipe took up alot of room and was a bear to setup in the summer heat.