high water pressure

Smart Irrigation Month is Here

The HEAT is definitely on!  Welcome Summertime!

You may have heard by now, that July has been deemed “Smart Irrigation Month” by the Irrigation Association since 2005, because that’s typically when the hottest temperatures occur (here in Central Texas, our hottest months are August and September). With high and hot temperatures come higher water use, it’s just a given. We still want our landscapes to look as good as they have the rest of the year, so we crank up the water.

This year, I’d like to challenge you to do something different. It’s been a slightly different year already: we actually experienced a winter (all Native Texans can appreciate that!!) AND it was a wonderful spring—again, that’s amazing since we usually go from winter straight to summer!  We didn’t have a 100-degree day until this last week and really haven’t needed to use the irrigation system until June.

In honor of Smart Irrigation Month, I’m going to ask you to something different by investing in your irrigation system and upgrade where necessary.  Don’t just turn it on and forget it all summer.  I want to focus on sprinkler heads and water pressure. The type of sprinkler head being used determines several things, like how long to water, where to locate the heads, and also how much water is being emitted and, most importantly, how well that water is being used by your landscape.

There are two main types of sprinkler heads—spray heads and rotor (or rotary) heads. Both are usually buried underground and pop-up when watering. Spray heads spray water the same piece of grass, or landscaping, the entire time they are popped up. Rotor heads turn to the left, right, or in a circle, when they pop-up and do not water the same place the entire time they are popped up.  They can have one large stream of water spraying out or smaller streams of water spraying.  With either pattern, they turn, versus being stationary. See the pictures on the right for what each look like.

Rotor heads are the more efficient of the two head types. Tests have shown that the water is distributed more evenly by rotor heads than spray heads. The same amount of water is being emitted close to the head as midway as at the furthest end of the water. Usually people want to replace rotors with sprays, but I urge them not to. Again, they are more efficient than traditional spray heads. Rotor heads are desirable to use in large areas—fewer heads are required to cover a large space since they spray water out a further distance than spray heads.

Traditional spray heads are not quite as efficient, mainly due to variations in water pressure and head spacing (specifically heads placed too far apart). Misting is commonly seen with spray heads—this is lots of “clouding” coming off the heads. This cloud, or misting, is water drops that are so small they are just floating away into the air, rather than going down onto the landscape. You are paying for this water and it’s just floating away. Not good. This means you have to run the system for a longer time to get water down onto the ground, which will get expensive and is just wasteful. This is caused by water pressure that is too high.

An aside here, “good” or appropriate water pressure for irrigation systems is between 35-60 psi.

High pressure can be remedied in two main ways: installing a pressure reducing valve (PRV) on the irrigation system, or replacing the nozzles with ones that adjust or compensate for the high water pressure. So…which is better? That’s a hard question to give a quick answer for.

The PRV is a good fix if the entire irrigation system is running with high pressure. It’s one device that is installed near the backflow prevention device in your yard. A licensed irrigator should be contacted to install this device.

Replacing nozzles is a great way to fine-tune the irrigation system; here, you can just replace nozzles in the zones that have the high misting. This is a little more time consuming because you need to find and purchase the correct nozzle types (full circle, half circle, etc) and then physically unscrew the old nozzles and screw on the new ones, but overall it’s pretty inexpensive. Of course, a licensed irrigator can be hired to do this work as well. There are several brands of nozzles that have built-in pressure compensation and can be ordered online or found in local irrigation stores.

Both types of pressure reducing qualify for the City’s Efficient Irrigation Rebate program. I highly encourage you to take advantage of it if you notice misting in your irrigation system!

Smart Irrigation Month, Pt 3: Sprinkler Heads

SmartIrrMonthSo we’re still in July and still talking about automatic irrigation systems for Smart Irrigation Month.  It’s seems this week summer has hit (again), maybe “for real” this time, so an efficient irrigation system is more important than ever.

I’m going to continue the same topic as last time, which is upgrading your irrigation system when necessary.  We talked about sensors last week.  This week I’d like to focus on sprinkler heads and water pressure.  The type of sprinkler head being used determines several things, like how long to water, where to locate the heads, and also how much water is being emitted and, most importantly, how well that water is being used by your landscape.

There are two main types of sprinkler heads-spray heads and rotor (or rotatory) heads.  Both are usually located underground and pop-up when it’s their time to water. rotor sprinkler

The spray heads are the ones that water the same piece of grass, or landscaping, the entire time they are popped up.  Rotor heads rotate to the left and right when they pop-up and do not water the same place the entire time they are popped up.  See the pictures on the right for what each look like.

Rotor heads are the more efficient of the two head types.  Tests have shown that the water is distributed more evenly by rotor heads than spray heads.  The same amount of water is being emitted close to the head as midway as at the furthest end of the water.  Usually people want to replace rotors with sprays, but I urge them not to.  Again, they are more efficient than traditional spray heads.  They emit, on average  gallons of water per minute.  Rotor heads are desirable to use in large areas-fewer heads are required to cover a large space since they spray water out a further distance than spray heads.spray head

Traditional spray heads are not quite as efficient, mainly due to variations in water pressure and head spacing (specifically heads placed too far apart).  Misting is pretty commonly seen with spray heads-this is lots of “clouding” coming off the heads.  This cloud, or misting, is water drops that are so small they are just floating away into the air, rather than going down onto the landscape.  (See the picture, all that stuff in the air above the plants is the water droplets from the irrigation system).  You are paying for this water and it’s just floating away.  Not good.  This means you have to run the system for a longer time to get water down onto the ground, which will get expensive and is just wasteful.  This is caused by water pressure that is too high.

An aside here, “good” or appropriate water pressure for irrigation systems is between 30-50 psi.  high water pressure 2

High pressure can be remedied in two main ways: installing a pressure reducing valve (PRV) on the irrigation system, or replacing the nozzles with ones that adjust or compensate for the high water pressure.  So…which is better?  That’s a hard question to give a quick answer for.

The PRV is a good fix if the entire irrigation system is running with high pressure.  It’s one device that is installed near the backflow prevention device in your yard.  A licensed irrigator should be contacted to install this device.

Replacing nozzles is a great way to fine-tune the irrigation system; here, you can just replace nozzles in the zones that have the high misting.  This is a little more time consuming because you need to find and purchase the correct nozzle types (full circle, half circle, etc) and then physically unscrew the old nozzles and screw on the new ones, but overall it’s pretty inexpensive.  Of course, a licensed irrigator can be hired to do this work as well.  There are several brands of nozzles that have built-in pressure compensation and can be ordered online or found in local irrigation stores.

Both of these types of pressure reducing efficiency qualify for the City’s Efficient Irrigation Rebate program.  I highly encourage you to take advantage of it if you notice misting in your irrigation system!

Sooo…What is Water Waste?

Are you are aware of by now, the City has been in Stage 1 of our Drought Contingency Plan (DCP) since October 2013.  We’re still in them, still Stage 1.  At the beginning of the month, we started increasing enforcement of the restrictions and water waste by putting some signage around town, leaving door-hangers on homes where we’ve seen non-compliance, and sending postcards out to others regarding problems with water waste, watering on the wrong day, and other things.  So, it’s easy to understand what day you can water your yard on, and it’s very easy to figure out not to water during the heat of the dayleaking head…but what is water waste?

To put it simply, water waste is just that–wasted water.  Water that isn’t used for any purpose, it just flows or leaves a property without any benefit to that property.  There are several things we look for specifically when talking about water waste: broken or leaking heads or valves, runoff, water ponding in a gutter or parking area or street, overspray, and misting.  Let’s look at each of them up close.

    • Broken or Leaking heads or valves–this really could be more generalized to include anything broken or leaking water that can be fixed.  Broken sprinkler heads are what people typically think of as huge water wasters, but it’s really not the case.  Sure, they do use a little more water each minute the system is running with the broken head, it’s really the leaks that are leaking constantly that add up to trunoffhousands of gallons of water overtime.  This could also include the leaky faucet on the outside of the house.  The picture at the top right shows a broken head–it’s spraying water straight up into the air rather than low, like the other heads.  There’s also high pressure here, a broken head may not always spray up that high.  In the second picture, there’s a leaking head that has been leaking for so long there’s algae growing on the sidewalk!  Not good.  This leak is running 24/7 so is wasting a lot more water than the broken head.
    • Water running off propertythe same leak as mentioned above can be used again.  Runoff is just like it sounds, it’s water running off the property.  The water from that leaking sprinkler head is running (flowing) down the street for at least 50 feet into the intersection of the next street.  Really, if you’re watering your yard, you want the water to stay on your yard, right?  If water is running off, it means you’re watering too long and the soil can’t absorb all the water so you need to reduce how long the sprinkler is running; if you have a sloped yard and the angle is causing the water to run off, same thing, reduce the runtimes and water it multiple times (i.e. run it for 5 minutes once an hour at 3am, 4am, 5am so it would water for a total of 15 min.). If a sprinkler head is turned the wrong way and spraying more onto a hard surface (driveway, sidewalk, street) rather than the yard, that causes runoff too.  The head just needs to be adjusted to spray the grass.  All can be easily fixed.
    • Water ponding–This is wasteful, water just sitting in a parking lot or street gutter, or sidewalk that is just going to oversprayevaporate.  It’s caused by the same things that cause the runoff, above, and can also be a hazard due to the algae growth of standing water–people could slip and fall on it, bikes going across it could also slip or become unsteady. The standing water can also erode the pavement and break down the streets quicker than with normal wear and tear, causing added costs to the City to repair or replace them.
    • Overspray–this is an easy one.  It’s simply water that is over spraying the grass and landing in the street, or other impervious surface.  The nozzle can be adjusted to reduce how far the water sprays out by turning the little screw on the top of the sprinkler head clockwise.  The water that is landing in the street or sidewalk leads to runoff and ponding.  In the picture below, the overspray is evident by the wet pavement.  The sprinkler heads are behind the shrubs and spraying way out onto the sidewalk.  misting
  • Misting–this is caused by too high water pressure.  It’s a waste of water because most of the water is simply floating off into the atmosphere, rather than going down onto your yard.  The water droplets are so small, due to the force (the water pressure) pushing them out of the sprinkler nozzle, that the wind then carries them off.  The water droplets need to be larger, heavy, to fall down onto your yard.  Ideally, the sprinkler psi should be between 30-50psi.  If you have high pressure and misting, it can be reduced by installing new sprinkler nozzles with built in pressure regulation or installing a pressure reducing device on the entire system.  The City’s efficient irrigation rebate covers both of these ways to control high pressure.  In the picture below, the misting is the cloud-like appearance of the water spraying out of the sprinkler head.  It shouldn’t be like that, when the sprinkler is running, you should be able to see the individual water drops.

So you can see that a lot of these problems are related and often times caused by each other.  It’s easy to fix them with some simple adjusting of sprinkler heads or runtimes (minutes) in most cases. I ask you to make those changes and help save some water and some money!