Pumping From Pond For Sprinkler System

GGB · May 23, 2012

I'm on a rural water system and it gets pretty expensive when I need to water the lawn. So I'm looking for input on what it would take to pump from our 2 acre pond. I'm not trying to create a golf course, but just keep the lawn reasonably healthy (1" per week as is recommended for fescue) when we aren't getting enough rainfall, like right now. I know the tradeoff is the additional cost of electricity, but am assuming that would far less expensive than the cost of the rural water, but let me know if that is wrong.

Our sprinkler lines are 3/4" with 4 heads per zone, and 8 zones in total, with a 1" supply line. I'm thinking of a setup where I could use quick connect fittings in order to move the pump to our other pond to do the same thing occasionally, althought just using tripod sprinklers on that one.

The pond is only about 60' from the backflow valve where I would hook into the current line, and it would only need to pump up about 3-4', depending on the level of the pond. I have 115 volt electrical service nearby which runs the septic tank lift pump, so that is already there. I still have the old pressure tank if that was needed, which was in service before the rural water system was available, although I'd prefer not to have to use it. By the way, I would not want to use the old well, as it didn't deliver enough water for normal household use, let alone trying to water a lawn.

I'm thinking I would just set up and turn on the pump and run only when I want to water. Any suggestions on the feasibility and what pumps to look at? Thanks.

Egon · May 23, 2012

It all depends on your required pumping rate and pressure requirements.

If low just an ordinary jet pump will work nicely.

If much higher start looking at a down hole pump properly set up in the pond and meeting your requirements.

rsewill · May 23, 2012

Check with your local water resources board to see if pumping from your pond is ok.

Kays Supply · May 23, 2012

If it is practical, a submersible pump is much easier to deal with and you get more bang for your buck. If you take the check valve out of the pump and just turn it on and off as needed, it can stay in the pond year round as long as it is below frost / ice level. If you use a poly pipe it won't hurt it to be above frost line. If your RPZ has unions in it , you could run poly to it and put a half union on the poly and connect it right to your existing system. You could even run it under ground and valve and tee it into the output side and make it a simple change over. If you do that, you might need a vacuum break so it will drain back. Check local codes, you may have to disconnect it from the city water to meet code.

J_J · May 24, 2012

A good A.O Smith 1 HP motor and pump, will pump all the water you could want. No problem with horizontal suction.

Float the draw pipe, a 2 ft, 1 1/4 pvc pipe with a filter on the end using an inner tube, then to the check valve and to pump.

Pumps up to 55 GPM or up to 40 psi . If your sprinkler heads put out 3 GPM, each leg could run 18 heads.

1/2 HP will only give about 6 GPM.

http://youtu.be/LRezWos2QUM

Carl_NH · May 24, 2012

As JJ says float the suction pipe - could use a gallon bottle also and a weight so it stays in place off the bottom of the pond with a check valve in the end.

With 115V available I would go with a 1/2 HP jet pump - 6 GPM should nicely cover 4 heads @ 1 GPM each.

I would disconnect the city water feed or add a shut off valve in the 1" line - not to trust the backflow preventer as you dont want pond water in your house.

Another more permanent option is dig a 4-5' deep hole 2-3' back from the pond and put in a 8-10" perforated pipe and put the suction pipe in that - the ground is a natural filter.

GGB · May 24, 2012

Thanks all for the input-this helps a lot. I hadn't thought of floating the intake line, so I'll definetly do that now. And I'll check on the GPM for the heads.

I'm leaning to using a 1HP motor, as I now realize I still have to have enough pressure to push the water up another 9' for the system in the front yard. Also, there is already a shutoff valve just before the backflow valve which I was going to use when pumping from the pond.

J.J., thanks for the link to the website. I'll check them out. By the looks of our weather pattern, I'd better be doing it pretty quickly. It's really gotten dry again in our area.

Fossil Farm · May 24, 2012

Depending on your sprinkler heads, you may need to filter the pond water as to not plug the heads.

Carl_NH · May 24, 2012

Fossil Farm,

You make a very good point - its not the nozzles, the valves too if they get a piece of dirt or sediment in them and they dont close, leaking and not shutting off. Our 16 zone system was a PIA every spring on the restart until I installed a 1" filter on the pressure line due to crap on the seats of the valves. Since that time no leaky valves not shutting off.

Taking apart valves in the ground is no fun - so a 1" pressure side filter is great, but also as mentioned a suction side pit close to the pond will filter the water, or wrap some wound polyethene (think rolled ridge vent) around the suction pipe and pull a nylon bag over it to keep the debris from getting in.