Overspray is probably the most common issue we find on sprinkler systems and is a big waste of water. As the name implies, overspray happens anytime the water from a sprinkler head overshoots the grass and waters something that shouldn’t be watered like a driveway or fence. The most common areas in which overspray is present are side-strips, the thin area of grass between the sidewalk and the street. Whenever overspray occurs, that water is being wasted and often just goes down the storm drain.

Overspray can be caused by all sorts of other issues including inappropriate head types or nozzles, incorrect spray patterns, tilted heads, or even high pressure. Since each issue that causes overspray has a unique solution, read on below to learn how you can reduce overspray in your system.

Usually one of the easiest problems to spot, broken heads can waste a lot of water if not fixed promptly. Broken heads range from a small crack in the plastic body (possibly caused by a lawn mower running over it one too many times) to a geyser-forming break like the one in the image to the left.

In either case, water will pool around the head, and prevent the water from reaching its intended destination. So apart from wasting water, a broken head will also prevent your grass from getting the water it needs.

Unfortunately, a broken head can only be fixed by replacing it with a new one. Be sure to purchase the same make and model as the head you’re replacing. You can usually take a picture of the broken head into your local hardware store and they should be able to help you identify the right head to buy. Once you have the new head, carefully dig a hole around the broken head, exposing the connection to the underground pipes (it helps to keep the dirt and sod you dig up in one piece). Simply screw off the old head, screw on the new head, and return the dirt and sod to the hole, making sure the head is level with the ground.

Here’s a great video from Hafen Acre that shows you the process for digging up and replacing a broken head.

Along with low heads, the most common problem found on sprinkler systems is tilted heads. Over time, sprinkler heads settle, tilt, and sink due to the natural compaction of soil, foot traffic, and lawn mowers running over them. When a sprinkler head tilts in one direction, it changes the spray pattern from the original design. That change can cause uneven distribution of water, meaning some areas of your grass won’t be getting any water while other areas might get too much. This creates brown spots where grass isn’t getting enough water or causes run off where areas are getting too much water, or the head is now spraying the side walk.

Fixing a tilted head is fairly simple, though care should be taken not to hit and break the underground pipes. In order to fix tilted heads, simply use a shovel to dig around the head, remove the sod and carefully clear the vicinity of dirt. Next simply lift and straighten the head, packing soil under and around it until it is even with the ground and can easily clear the grass when it pops up. Then replace the sod piece back in place over the sprinkler head. For a more detailed explanation, watch this helpful video from Orbit.

Along with tilted heads, the most common problem found on sprinkler systems is low, or sunken heads. Over time, sprinkler heads settle, tilt, and sink due to the natural compaction of soil, foot traffic, and lawn mowers running over them. When a sprinkler head sinks low enough, the sprinkler is unable to pop-up above the grass, causing the water to hit the grass immediately around the head and prevent the water from reaching it’s intended area. Often this causes uneven distribution of water leading to brown, dry spots of grass and misting, the forming of small water droplets that are easily blown away by the wind or evaporated.

Fixing a sunken head is fairly simple, though care should be taken not to hit and break the underground pipes. In order to fix sunken heads, simply use a shovel to dig around the head, remove the sod and carefully clear the vicinity of dirt. Next simply lift and straighten the head, packing soil under and around it until it is even with the ground and can easily clear the grass when it pops up. Then replace the sod piece back in place over the sprinkler head. For a more detailed explanation, watch this helpful video from Orbit.

Just as the name implies, blocked heads are caused by an obstruction that prevents a sprinkler’s water from getting to where it needs to go. The most common obstruction are rocks, overgrown bushes and trees, or even really tall grass. With an obstruction blocking the spray from a sprinkler, the grass that should be getting water isn’t getting nearly enough. This will cause dry, brown spots in your lawn.

In order to fix the issue, you’ll need to remove the obstruction so that water can return to its intended location. If moving the obstruction isn’t possible, you’ll likely have to move the sprinkler head that’s being blocked. This is likely a far more time intensive and costly solution than removing the obstruction, so we recommend hiring an irrigation professional if moving a sprinkler head is necessary.

Clogged nozzles are caused by debris getting stuck in the nozzle or the filter of the head, most commonly in spray heads. This clog prevents the water from covering the entirety of the head’s intended coverage area and can lead to dry and brown spots.

Luckily, a clogged nozzle is one of the easiest problems to fix. First, make sure the system is off (you don’t want a wet surprise!). Then, simply lift the stem out of the head by the nozzle, screw the nozzle off of the spray head, making sure to hold onto the stem, or clamp it to prevent it from dropping back into the body. Take the filter out of the stem and wash out any debris in the filter or nozzle. Put the clean filter back into the stem and screw the nozzle back on to the stem. Finally, make sure to adjust the spray pattern to ensure that water is spraying on the intended coverage area.

For a better look at fixing a clogged nozzle, check out this video from the City of Round Rock, Texas.

Mixed heads, otherwise known as mixed zones, occur when a single irrigation zone has more than one type of sprinkler head. This is a very common design flaw on many sprinkler systems, and usually means there are some rotor heads and some spray heads on the same zone. It might not seem like a big problem but usually creates a nightmare when it comes time to program the control clock.

Since spray heads are designed to emit about 50% more water than rotor heads in the same time period, some areas of the mixed zone will either receive far toomuch water or not nearly enough. For instance, say you have a zone with 4 spray heads on one side and 4 rotor heads on the other. If you programmed the schedule to water just the right amount for the spray heads, the rotor heads won’t have enough time to give their area of grass as much water as it needs. Alternatively, if the schedule is meant for rotor heads, the area of grass covered by the spray heads will be getting too much water. So, either way its a tricky situation that could lead to either dry, brown spots of grass, or wasted water.

Unfortunately there isn’t an easy fix. In addition to spray heads emitting more water than rotors, they shoot water shorter than rotors. So if you were to simply to replace all of the spray heads with rotor heads, you would likely be causing overspray and wasting even more water. Depending on the design of your system, we recommend hiring a sprinkler professional to make some adjustments and slightly redesign the sprinkler system to create uniform zones.

Misting is relatively self-explanatory but the causes and solutions can vary widely. Misting turns the normal spray from a sprinkler head into a cloud of fine mist consisting of tiny water droplets. This mist is then easily carried away by wind or simply evaporates, wasting precious water. Misting may be caused by blocked heads or clogged nozzles, but the most common cause is high water pressure.

In order to fix this issue, make sure there are no obstructions in the way of the sprinkler’s spray pattern and ensure all of the nozzles are free of debris. If the problem still persists, it is likely a pressure issue. To reduce the pressure on the affected zone(s), you’ll need to install a pressure regulator on the valve that feeds a particular zone. Pressure regulators can be purchased online or your local hardware store that carries irrigation equipment.

Broken or leaking underground pipes is the most difficult problem to see with the naked eye. Since the pipes are buried a few feet underground, it’s difficult to spot without digging. And, as you can guess, a broken pipe can waste a lot of water and go unnoticed for quite some time. The two most tell-tale signs of broken pipes are overly soggy wet areas (if you’re not overwatering) or the sprinklers on a zone might not be popping up all the way and aren’t emitting water as far as they should be.

If you’re concerned you may have a broken pipe underground, we highly recommend getting in touch with a certified sprinkler pro to find the leak and repair the pipe for you.

A sprinkler system’s control valves are arguably the most important piece in the system. The valve communicates with the control clock, telling it to open and provide water to the zone it controls. If the valve is broken it is unable to distribute water to its zone or only distributes a small amount of water to the zone, leaving the sprinkler heads unable to pop up all the way and emit the amount of water the grass needs.

A broken valve will need to be replaced and since it is a more technical piece of equipment, we recommend hiring a sprinkler professional to install the new valve.

If left unchecked, improper pressure can cause some serious problems on the sprinkler system, and will result in very inefficient watering. High pressure causes smaller droplets to be sprayed out of the sprinkler head, see “Misting”.  This results in water being blown down the street or evaporating into the air. Consistently high pressure can also cause sprinkler heads to wear out more quickly, meaning you’ll have to replace them more frequently.

Low pressure prevents the heads from popping up all the way (like the image to the left), resulting in poor coverage and dry, brown spots of grass. While high pressure can be fixed by installing a pressure regulator on the affected zone, fixing low pressure isn’t so easy. Often times, low pressure is an indication that something else is wrong on the system, such as a broken head, leaking pipe, or malfunctioning valve.

When a sprinkler system is designed, it should incorporate “head-to-head spacing.” This means the spray of one head should reach the closest heads around it to ensure an even distribution of water. Without head-to-head spacing, a zone has probably has uneven distribution with poor head spacing. With that uneven distribution, some grass on the zone won’t get as much water as it needs, resulting in dry, brown spots of grass.

Unfortunately the only sure-fire fix to poor head spacing is completely redesigning the zones with the problem. If you choose to go this route, we definitely recommend working with a qualified sprinkler company to ensure the new design incorporates head-to-head spacing.

There are two common types of sprinkler heads; spray and rotor. Spray heads, with a shorter throw distance, are designed to cover smaller areas of grass like a front yard or side strip. Rotor heads, on the other hand, have much longer throw distances and are meant to cover larger areas of grass like a back yard or a ball field.

If spray heads are used on larger areas of grass, it’s likely that that grass won’t be getting covered with water as well as it should. That would result in dry, brown spots of grass. Alternatively, if rotor heads are used on a small patch of grass, you’ll almost certainly be left with overspray and waste water. Both instances are examples of an inappropriate head type being used on a zone.

To fix the issue, simply replace the inappropriate head type with the correct one. In some cases of spray heads being used on a larger zone, you may be able to replace the nozzle with a high-efficiency rotary nozzle. But make sure to increase the run time on that zone as high efficiency rotary nozzles emit one-third the amount of water a spray nozzle does in the same period of time.

When discussing incorrect nozzles, we mainly identify issues on spray heads. While rotor heads have nozzles, it is far more common for spray heads to have incorrect nozzles that affect the efficiency of the sprinkler system. A key term to understand on spray head nozzle selection is arc; the area of a circle a sprinkler head waters and is measured in degrees. So, if a nozzle has a 90 degree pattern, it waters a quarter of a circle, 180 degrees waters half a circle, and 360 degrees waters a full circle.

Depending on the arc of the head, an incorrect nozzle can have two impacts on the efficiency of the system. If a nozzle has an arc that is too small for the area it covers (think a 180 degree nozzle on an area that should have 360 degrees like this image) part of the grass will not be receiving as much water as it should, resulting in dry, brown spots. On the other side, if a nozzle has an arc that’s too large for the area (say a 180 degree nozzle on a corner that should have 90 degrees) it will result in significant overspray and lead to wasted water.

Luckily, the fix is relatively simple and inexpensive. Usually, you’ll just have to replace the nozzle with one that has the appropriate arc, or with a variable (or adjustable) arc nozzle. These variable arc nozzles allow you to adjust the arc to fit your system appropriately.

Check valves are a device inside a sprinkler head that essentially seals the head, preventing any water from leaking out of it after the zone turns off. This keeps water in the underground pipes and prevents gravity from pushing the leftover water out of the lowest heads in a zone. So, if your system lacks any check valves, you’ll probably notice a small stream of water coming from one or two heads on a zone after it turns off.

If you don’t have check valves, we highly recommend installing new heads with check valves built in on the lowest points in a zone, particularly if there is a slope in your lawn. Many newer models of heads have check valves built in. So when purchasing a new head, be sure to look for models that have check valves.