Getting the most out of your irrigation system that is running on a well

Wells for irrigation systems are very common these days.  Many people have realized that it is much smarter and cheaper to irrigate their lawn with well water rather than city water.  And almost no one has enough rainwater to irrigate a lawn.  So, if you have a well that waters your lawn, you are one of the smart ones.  But there are some problems that arise in the use of well water for lawn irrigation that you need to be aware of. 

Most irrigation systems are set up to run on city water.  Irrigation contractors install irrigation systems for houses that have city water and/or well water.  But the vast majority of the installations are on city water only.  So, when they design the irrigation systems, the industry standard is to design and build the system around city water.  But many times, the optimal method for using a well is different.  So, lets look at a few changes that you can make to your irrigation system and your well to get the maximum benefit.  Note that many of these things are free or have minimal costs.  I recommend you start with the free ones first.  If you need more benefit, you can always start spending money.

Most irrigation systems are set up to water the entire yard in one night.  That way you can follow the irrigation restrictions that municipalities place on lawn sprinkling.  When the city says you can only water one or two days a week, then you had better have your controller set up for that or you get a fine (and a nasty look from your neighbors).  But your well doesn’t like this.  The well must run for several hours at a time to irrigate your yard.  The longer the pump runs, the more stress you are putting on your aquifer.  If your well makes 30 gpm and your irrigation system is demanding 25 gpm, it sounds like you could water indefinitely without any problems, right?  Yes, but that 30 gpm flow will fluctuate.  It will slow down some in the dry months when you need it the most.  And if your neighbors are all watering their yards at the same time then you are all pulling from the same source, and everyone loses.  You are asleep at night while your irrigation zones are running.  The first few zones are fine.  The wells are sitting full of water at the start up and you go to bed thinking everything is fine.  But that 4th zone only gets about half its water because the well sucked air and the pump shut off for a while.  You don’t notice until the grass turns brown.

The solution here is spread out your watering.  First of all, water every night of the week.  Now irrigators will tell you its not good to water a little on your grass every night, and they are right.  The grass needs a good watering and then a few days to let the soil dry out.  But you could water the front yard tonight, the back yard tomorrow, and the side yards the next day.  And then repeat that.  You are watering 1/3 of the normal amount each night and you are not stressing the aquifer as much. 

Another neat trick is to put in a delay between zones.  Water zone 1 and then water nothing for 30 minutes.  Then water zone 2 followed by another delay.  This allows your well to recuperate between zones.  Many irrigation controllers will allow for this.  But if yours does not, you can do what I did.  My controller is a cheap one and doesn’t have a way to have a delay.  I created a zone that doesn’t water anything.   Its zone 6 in my controller.  So, I water zone 1, and then zone 6, and then zone 2, and then 6, and zone 3.  The next night I water zone 4, 6, 5, 6, 7.  By doing this I always have a full well for each zone.

Ok, that is all the free tips.  The next one could cost you a little (but not too much).  Most irrigation systems are set up to use between 20 and 25 gpm.  City water meters typically supply 30 gpm, and the irrigators want you to have some water pressure in the middle of the night for the occasional shower or toilet flush.  But, if your well struggles to give you that flow, you can have your irrigation system adjusted to use less water.   This can be done in two different ways.

You can split up some of your biggest zones.  Have your irrigation contractor analyze the demand of each zone.  Those that are too big can be split in two.  If you were on city water, this might be a problem as you need to finish watering everything in one night.  But, on a well, you are not restricted to those daily watering schedules.   So split those zones and use half as much and give your well a break.

Another trick is to replace your irrigation heads.   Many irrigation heads have replaceable nozzles in them.  Let’s say you have a zone that has 6 heads each demanding 4 gpm.  That adds up to 24 gpm.  You probably will water that for 20 minutes.   If you change those nozzles to 3 gpm nozzles, then your demand drops to 18 gpm.  You will need to run that zone a little longer to put the same water on the yard.  But you didn’t stress your well as much.  Remember, time is on your side now that you have a well.  If your heads don’t have replaceable nozzles, then it might be time to spring for some new heads.

And now we move on to the well.  Here are three things you can do to get more water out of your well.  Add a storage tank system to your well.  You can have the well fill up a large tank that is filled throughout the day.  Then when you want to irrigate, your water is sitting in that tank ready to go.  It really makes a huge difference.  Instead of putting all your demand on your well in just a few hours, you can spread that demand over 24 hours, and you will be amazed at the results.

If you need to get more water out of the well, you may get some good results from jetting your well.  Jetting is a process where we clean out the bottom of the well.  There is usually some mud sitting in the bottom that is slowing your production.   That probably needs to be cleaned out every 10 to 20 years so that you get all the production.  We pull the pump and run a pipe to the bottom and blow all the sediment out of the well.

Another neat trick that we use is to acidize your well.   In this process, we pull the pump and inject acid into the rock formation that will eat away at the veins of the aquifer.  This opens up those channels for water to flow faster.  It doesn’t work on every well situation but on average, we see this triple the flow water available for your pump.

One other potential help is to lower your pump in the well.  Back when it was drilled and the water was high, you didn’t need to set the pump that deep.  But now, with the drought, you may need to be lower the pump to get all the available water.  The last trick is to deepen your well or drill a new well.  Of course, this is the most expensive option so I hope you can solve your irrigation problems without drilling.  But, if you need us, we can handle any job.