The Fourth of July and what I can’t do.

Well, I tried and couldn’t do it. Couldn’t figure out how to tie the Fourth of July into irrigation systems.

You’d think this would be easy. I’ve tied in zombies, Corvettes, the Bellagio and the Nile river into some aspect of irrigation: stream rotors, insecticides, nozzles and water barrels.

These have, admittedly, been a stretch at times.  Big stretch.  Can’t do it this time.

Instead, the staff at Sprinkler Warehouse hopes that you and yours have an enjoyable holiday. This is the day that started our country. On July 4th, 1776 the Second Continental Congress approved the Declaration of Independence, one of the most important documents in history. It’s the reason we are here. It’s a great day to enjoy and celebrate our freedoms.

Be careful with the fireworks. From experience I’ll tell you that you don’t want to hold bottle rockets in your hand, firecrackers going off in an open palm DO hurt, you don’t want to bend down to see if the rocket fuse is really lit, if you drop your sparkler don’t try and catch it by the wrong end and the best way to enjoy fireworks is to sit back and let someone else do the work.

Y’all have a good holiday.

Pipe Dreams? Or PVC Pipe dreams? There is a difference.

If you don’t know the difference we can’t help you here. This is not that kind of a blog. If you have nightmares about figuring out which pipe to use for your irrigation then we can help.

PVC stands for polyvinyl chloride. PVC is easier to say. PVC pipe accounts for about two thirds of the water distribution market, including drinking, irrigation and waste. So far the material has been found to be inert, meaning it doesn’t absorb or release harmful chemicals. Unless you burn it. Don’t sniff burning PVC.  It’s no fun, painful and the smoke can be hazardous.

The most common question we get is a two-parter: what size pipe should I use and what kind: Schedule 40 or Class 200? Knowing the differences can help you create an efficient system.

Remember the old “a picture is worth a thousand words” quote? I’ll give you a picture now and you can decide if you want to skip the other 476 words.

Let’s talk about Schedule 40 pipe first. It is the simplest. Schedule XX designates the wall thickness at a certain size. For example, a 1” pipe in schedule 40 has a wall thickness of .133”; schedule 80 has a wall thickness of .179”. Higher schedule = thicker wall.

You will care about this later. It does get more interesting, hopefully.

“Class” pipe is different and the original definitions go back to steam boilers. We’ll skip ahead. Class 200 pipe, the most common class pipe used in irrigation, is rated for 200 pounds per square inch pressure (psi) and has a wall thickness of .063” for a 1” pipe. Notice that is a lot thinner than schedule 40. This is about to become very important. Schedule 40, in comparison, is rated for 450 psi. This is not as important.

The average irrigation system is designed for about 30 to 50 psi. Plenty of safety factor built in. It is not, however, as much as you think. A poorly designed system can experience water hammer and a 60psi line can experience frequent surges of pressure up to about 170 psi. Still within safety range.

Now we can get into the “why do we care” part.  Everything in irrigation ties into gallons per minute. Your spray head puts out a certain number of gallons per minute (gpm). Your design revolves around it. If you have 13 gpm you can put six 2 gpm heads on that zone. Or four 2gpm and four 1 gpm. (Never design to the absolute max gpm.)

Look at the cross section of ¾” and 1” pipe both in schedule 40 and class 200. Check the comparative flows in the picture above. This difference in flow can make a big difference in how you design your zones. There are friction loss/flow charts available to help you.

So what do you choose? The rule of thumb is to use schedule 40 for the main line. Run it from the water meter, through the backflow and to the valves. Then use class 200 for the laterals, or after the valves.

Why schedule 40 when it allows fewer gallons per minute? Because the thick wall makes it tougher, harder to break. Your main is under constant pressure; the laterals are under pressure only when they are active and it is an open-end system. Before real pressure can build in your laterals the water is shooting out the sprays, keeping pressure down. Schedule 40 is more resistant to shovels (its sworn enemy), tent stakes, car tires, kids, dogs and other puncture/crack pressures.

There are exceptions to everything. There are situations where an entire system should be done in class 200 pipes. Same for schedule 40.  Now that you know the difference you can make a more informed decision and start dreaming about better things, like a 1973 Norton Commando.

Backflow = upchuck? Eeeewww…

Most people know they need a backflow for their irrigation system. They just don’t know why. I’m going to work this backwards. First I’ll show what can happen if a backflow is missing or broken. Then I’ll tell you how they work and why you want one for your system.

From the West Virginia Department of Health and Human Resources: “One of the most highly publicized cases of a backflow incident occurred in 1969 at Holy Cross University. The football season was canceled due to a large outbreak of infectious hepatitis among the team members. It was determined that backflow through an unprotected lawn sprinkler system at the practice football field caused the epidemic. Children carrying the hepatitis virus routinely played in puddles around the sprinkler heads. Fire fighting demands in the vicinity caused negative pressures at the sprinkler heads backsiphoning the contaminated water into the drinking water supply to the field.

One of the most famous cases of backflow occurred in California. A laborer had been using an aspirator attached to a garden hose to spray a driveway with weed-killer containing arsenic. At sometime during his work, the water pressure reversed. The man then disconnected the hose and unwittingly drank from the hose bib. Arsenic in the waterline killed him.”

Thirsty yet? Try this from the Environmental Protection Agency: “In 1991, an atmospheric vacuum breaker valve intended to protect a cross-connection between an irrigation system and the potable supply malfunctioned, allowing backflow of irrigation water into the public water system. The water system, located in Michigan, was contaminated with nematodes, rust, and debris.

In 1981, chlordane and heptachlor were backsiphoned through a garden hose submerged in a termite exterminator’s tank truck in Pennsylvania. An undisclosed number of illnesses occurred, and 75 apartment units were affected.”

THE BASICS If you lose water pressure to your house, for whatever reason, the water in the house will flow out to the main line. Because pressure is now reversed, going from house to main line, it creates a siphon effect and will pull anything in the sprinkler system and in the puddles around the sprinkler system with it. If your garden hose was on at the same time it becomes a siphon hose. Now all the fertilizer, insecticide, animal waste and many other things you don’t want are pulled into the drinking water.

GARDEN HOSE Notice the two involving garden hoses? How many of us drink from a garden hose when working outside on a hot summer day? Ever use that same hose to put out pesticides or fertilizer? Have a backflow preventer on the hose bib? Cheap, cheap protection.

I think it is important at this time to note that our very talented graphics department has absolutely nothing to do with the illustrations in this article. I stole their work and added my own touches.  I get the blame.

IRRIGATION SYSTEM Same principal. Have another bad drawing. A backflow works by shutting down the irrigation water line when you lose water pressure. The simplest works just like a stopper in your bathtub: a plug falls down, blocks the line. They get far more complicated, depending on application.

Don’t listen to your neighbor, me, anyone else on what type of backflow you should get. Ask your city or county or your water provider. In my area a pressure vacuum breaker is plenty. Two miles away a new jurisdiction starts and they insist on double-checks. Always verify local code requirements first.

To find out the different types of backflows look at the backflow section on To learn more about how they work check out backflows in Sprinkler School.

And stop drinking from your garden hose until it’s protected. Lemonade sounds better anyway.

Can’t afford a trip to the Bellagio? Stream rotors + your music + your lawn chair = you’re there!

The fountains at the Bellagio, Las Vegas, are world famous. They are designed to take you away from stress and trouble with their combination of dancing water, music and light. They are not, however, designed to keep you from gambling.

Each performance is a unique interpretation of a classic piece of music.  Their definition of classic covers a broad spectrum: Mozart, Glenn Miller, the Beatles and more. I hope they are working on Hank Williams. That might take a while. His work is pretty complicated.

If you can’t make it to the Bellagio, bring the fountains to you. Get stream rotors for your yard. You will enjoy the relaxing show and you will water your yard at the same time. Having a beautiful yard helps you relax even more. You benefit in many ways.

Stream rotors are different from standard rotors in that, instead of blasting a great deal of water out of one nozzle, they produce multiple streams of water of lower volume. These streams come out at different angles, some high, some low, ensuring even coverage. If you have sloped land the slow, even coverage minimizes the chance of water runoff. Blasting gallons of water every minute at sloped land just encourages runoff, as the soil cannot absorb the water as fast as it is applied.

In traditional stream rotors the Toro 340 is the answer. Designed to replace impact or gear driven rotors with a ¾” inlet it covers from 15 to 30 feet. It also has 9 easily set patterns to cover most any area. Great coverage, great application.

Don’t have a commercial application? Looking for the Bellagio effect at your home? No problem. In the last few years a number of manufactures have developed stream rotors that fit standard pop-up spray assemblies. The stream nozzles simply swap out with the standard spray nozzles and you are in business. Rain Bird and Hunter have every situation covered.

Not sure why you want to get rid of your old nozzles? Two good reasons come to mind. First, the stream nozzles cover up to 30 feet, where spray nozzles stop around 15 to 17 feet. This means that in many systems you can have the same coverage while eliminating a number of heads, saving water. Second, stream nozzles are not as sensitive to breezes as spray nozzles. The droplets are bigger and heavier; they go where they should when standard sprays are being blown away. Wait, I’ll add a third, no charge.  A zone with stream rotors can use 30% to 40% less water for the same coverage. Less water = less money.

The reason for their efficiency lies in their pattern. Small streams, slow application and constant, even movement add up to  more consistent, usable irrigation.Take a look at the spray pattern below.

Notice how closely it matches the Bellagio fountain pattern? Quality knows quality.

So turn on the stream nozzles, add music, sit back and enjoy the show. You can charge your neighbors admission if you wish. After all, look at the money you saved them by bringing the Bellagio to them.

And How Did You Tie Corvettes Into Sprinkler Nozzles?

Life is good. You just bought your first Corvette with all the features: 6.2 liter 430-hp LS3 V8, Bose® audio system, head-up display and, to top it off,  Mickey Thompson Baja Claw TTC radial tires for off-road mudding! Race track here we come!

Life gets better! You just moved into your dream home: ocean view, indoor pool, master chef kitchens (two, so you don’t have to walk too far), a personal theater furnished by Home Theater Gear, a private elevator and, out back, your own personal outhouse!  Time for a party!

In any system all parts must work equally to achieve the desired results. Let’s trade the Baja Claw tires for Goodyear Eagle F1 Run-Flats and see if we can’t get some plumbing into your new mansion.

Nozzles are the final and one of the most critical parts of your irrigation system. It does not mattop of a sprinkler nozzleter how good the system is; putting in the wrong nozzle will make it ineffective and a money waster.

Understanding nozzles is simple. For one, the notes you need are written right on top. It’s like having the answers to your history test on the same line as the question.

Look at the top of a standard nozzle. You’ll see three things: a number, a letter and some lines. On this sample the “10” means 10 foot radius, the “H” means Half Circle, or 180 degree coverage, and the line indicate the spray area. This notation is standard throughout the industry. A full circle nozzle has the distance and pattern but no line marks.

Specialty Nozzles

There are nozzles designed just for gardens and small areas. These are strip nozzles. Their patterns are as shown below.

sprinkler nozzle strip pattern diagram

Variable Nozzles

Variable nozzles are just that: variable. They can adjust spray patterns from 00 to 3600. Marking on these are usually the radius and either A for adjustable or VAN  or simply arrows pointing in both directions. These are excellent for small or unusual angles. To adjust you just turn the top ring or the side ring, depending on manufacturer.  Extremely versatile.

variable arc nozzles spray pattern diagram


Every manufacturer has specialty nozzles. Some are low angle, some are low flow, some have different nozzle design. Each has its benefits.  All, however, fall back to the same basic descriptions: they all have a radius/distance marking, they all have a pattern description.


There can be a great deal of difference in the amount of water two nozzles from different companies put out. For example a Hunter 15’ full pattern standard nozzle at 30psi puts out 3.72 gallons per minute (GPM). A Toro Precision series, same radius, pattern and pressure, puts out 2.31gpm.  That is a difference of 1.41gpm per minute.  Both fit a need and have a specific purpose. However, you do not want to mix the Hunter and the Toro on the same zone. You will either over or under water one area.

It is important to stay with the same manufacturer on nozzles to keep the same precipitation rates.

One Final Note

Most nozzles are female thread and will swap brand to brand without a problem. Some nozzles are male thread and are for certain brands only. Female thread tends to dominate the industry but make sure of what you have before you purchase replacements.

sprinkler nozzle threads

Every thing is good. You have the right tires, an actual indoor privy and perfect coverage for your yard.

Been to the Nile Lately? Bring mosquito spray?

The Nile is the longest river in the world, flowing through Rwanda, Ethiopia, Tanzania, Uganda, South Sudan, Sudan, and Egypt. In many ways it is literally the source of life and commerce for much of Africa. Remains of ancient civilizations abound on its shores, offering great insight into the history of the region. The area is well worth the visit, having something to offer everyone. Fortunately you only need to concern yourself with the East side of the Nile, which saves time and  money.

Why? Because mosquitoes are bringing the West Nile to you. In the 2011 Center for Disease Control study forty-five states had reports of West Nile Virus in humans. While the West Nile Virus is rarely fatal, with 80% of all people infected not even knowing they have it, it can have serious symptoms including neck stiffness, stupor, disorientation, coma, tremors, convulsions, muscle weakness, vision loss, numbness, and paralysis.  This is not good.

How do you avoid infections? First, strange as it sounds, don’t pick up any dead birds. Not sure why you would want to any way but don’t. Resist the urge. West Nile is very good at killing birds, crows in particular. If you do not know how the bird was killed (cat?) then assume it died of illness. If you must move a bird, use gloves or a shovel/scoop. West Nile is spread by mosquitoes biting infected birds and then biting you. Touching the bird will save the mosquito time and energy.

The next question becomes “How do I control mosquitoes?”

Glad you asked. Besides the standard suggestions about eliminating their breeding areas, you can simply kill them. That works pretty well to stop their biting. There is a system that can do that using your existing irrigation system. This means it covers your entire yard, not just part. It also means the insecticide goes to the low places that the water drains to.

The system is Skeet-R-Gone.mosquito control system for sprinklers Liquid pest repellent concentrate is injected into an existing sprinkler system by a 160 PSI pump that is housed in an exterior enclosure.  This enclosure also houses the concentrate.  The bug repellent concentrate is pumped through tubing that connects to a special mixing chamber and saddle valve.  The mixing chamber is installed directly into the water supply after the backflow preventer.  Once the pump is activated through the Skeet-R-Gone controller, the pest repellent will mix with water and be distributed throughout your yard by your sprinkler heads. mosquito control system for sprinklers

The all-natural pest control product is formulated with plant extracts from crops grown in North America. Precise blending with essential oils and spice extracts such as thyme, sage and oil of cedar give our Bug Slug Colloidal Pest Control muscle with NO hazardous chemical additives.

Some of the advantages of Skeet-R-Gone are:

  • Bug Slug Concentrate: Eco-Friendly
  • Bug Slug made from natural ingredients – it’s green!
  • Won’t harm grass, plants, people, or pets
  • Insects cannot build a resistance
  • Pesticide Free
  • High Performance
  • Contains no WHIMS regulated ingredients
  • Made from renewable natural resources

You and your family are far more important than the mosquitoes. At least, to us you are. Keep your health; stop the irritation, the scratching and the biting. Kill the bug.

By the way, it also kills flies, fleas, gnats, no-see-ums, mites, spiders, fruit flies, fire ants, chiggers, ticks, silverfish, crickets, moths, cinch bugs, ants, palmetto bugs and many more.

Anything that gets rid of fleas, ticks and chiggers has got to be good.