Question
QUESTION: I am running a 5HP deep well pump for an irrigation system producing/demanding roughly 20GPM per zone.  I have had too much trouble managing cycling with an 80 gal pressure tank.  I bought a new controller and pump relay to run the pump directly and only turned off/on by the controller.  However, I really worry about exposing various risk scenarios to the well pump.  Does it make sense to install a large 1000 to 1500 gal cistern and a much smaller irrigation pump adjacent to the well to provide irrigation pressure and only use the big well pump to maintain the cistern water level via high/low water switches?  The intent is to reduce the cycling, continuous running, and overall risk to the big well pump and move the risk a smaller surface mounted 1.5 HP surface pump.  I'd rather replace an irrigation pump myself at $400 rather than hire a pump company to replace the well pump $3K or $4K.

Thanks,

ANSWER: Your submersible pump will have the longest life if it does not cycle so often - I agree. Do you know the brand and model? At a first glance of your situation It seems that it may be oversized for what your actual irrigation system needs - kind of like being stuck in slow moving traffic driving an Audi that just wants to go full bore. Your storage tank and booster pump idea may be a good solution but before investing the money and the time let's find out a bit more.

Besides finding out what model of submersible you have - do you know any other information on your well such as depth to water level and recovery rate? If you have an irrigation system demand of 20gpm do you have a 1.5" or larger mainline? how many zones do you have and how long do you normally run them... these are just some surface questions to try and find out how much water you use in a typical irrigation cycle - if you ran the whole yard through in one night how much water is used? That's what we want to know and this will help determine the tank size you would need and the type of booster pump you will need. Also What kind of pressure do you have right now when the pump is operating? Can you snap a quick photo of the equipment and send it?

Let's start with that and get on the road to solving this for you.

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Pump House   QUESTION: Josh,

I gave you the wrong pump model in my previous response.  It is actually a Gould Model No. 18GS50412.

Answer
Leo: I think I was getting too detailed previously. Simply put, I think you should place a booster pump and a storage tank as you previously mentioned. One thing to keep in mind - your new 1500 gallon tank will be depleted in about an hour based on your 20gpm demand.You will need a float switch  for your submersible. I recommend going to and irrigation distribution house. I am unsure of where you live exactly. I'd be happy to point you in the right direction for qualified people that can help you in-person.

This type of problem is best worked-out on site and in person. I wish you the best and again, if it were me I would go with the tank and booster pump idea based on what you have told me.