What to look for in a reputable irrigation contractor

Winter is finally upon us and it has come with a vengeance!  The hottest driest summer on record has been followed by the wettest December on record.  Hopefully the winter snowpack increases so another hot summer will not bring the same drought conditions back to the mountains.  All of the exceptional heat and lack of water last summer brought a huge demand for the services of irrigation repair and installation technicians.

When looking for the services of a proficient irrigation contractor the first thing that you should check is if they are licensed, insured and carry a current bond.  All of these are required to protect you, the customer.  If an unlicensed, uninsured contractor hurts themselves on your property or installs a faulty system that fails and damages your house it may come down to your own insurance to coverage the liability.  Current licenses, insurance and bonding can be checked with the sate landscape contractors board at:  

http://www.oregonlcb.com/contractorsearch.aspx

When interviewing potential irrigation contractors they should at a minimum, take pressure and flow measurements, take dimensions of the areas to be irrigated and do a preliminary head layout with flags or a layout using on-line map resources.  Any contractor worth their salt will be able to tell you available flow and pressure as this will determine irrigation zone sizing and even which irrigation options may be available.  If a sprinkler zone is oversized it will attempt to draw more water than is available resulting in too-low pressure, poor spray patterns and a lack of head to head coverage.  The end result will be a sprinkler system with burned areas in the lawn and zones that have to be run much longer too cover up in-efficient spray patterns.

A new properly designed system built using quality parts is not inexpensive but hiring a contractor that is not properly trained tends to cost more in the long run due to in-efficient coverage, areas not getting sufficient water, repairs due to poor installation techniques and cheap parts.

Asking your potential irrigation contractor a few questions regarding what they know about your water supply,  how they will lay out & design your system and how they will maintain it will benefit you greatly.  This benefit will extend past your systems completion but will be reflected in how healthy your landscape is in the long run!

Sprinkler coverage problems

Now that we are entering the final stretch of summer you should have a good idea of what your irrigation system's weak spots are and where coverage is lacking.  If your system was designed properly & built properly so flow does not exceed supply and we have head to head coverage this shouldn't be an issue.  However, landscapes change over time with plants maturing and sod/beds changing shape; heads can get blocked or be in the wrong place. 

The first thing I do when evaluating a system that is new to me is to run through each zone and make quick arc adjustments to heads, flag out heads that need to be straightened, that are clogged or need to be raised.  This is much like the spring start up process and can vastly improve coverage in lawn areas.  These are things that you, the homeowner, can easily accomplish on your own while also getting to know your system better.  All you need are a pair of channel lock pliers, a shovel and a willingness to stand in the sprinklers on a hot day!  For more information on how to do these adjustments, please check out my two earlier blog entries on basic sprinkler system maintenance.  I also keep an eye out for heads that may be buried in bushes and either prune them back or move the heads out from under them so the spray pattern is less affected.

Sprinkler coverage can also be lacking due to poor design or installation practices.  The way this is usually characterized are by brown arcs or spots in turf or plants that aren't getting sufficient water in beds areas.  Proper irrigation design dictates that head to head coverage is necessary for even coverage; this means each head should be hitting the adjacent head.  Coverage that falls short will usually show in brown areas that, even if they are getting hit, are not getting adequate amounts of water.

Coverage issues that are due to insufficient flow, pressure or head spacing is a little more difficult to resolve. Usually if you can push a head that's running back down into it's body with your hand, the pressure is too low.  Most spray nozzles are designed to run at 30 psi and most rotor heads are designed to run at 45 psi, if you can easily push the head down with your hand the operating pressure is less than 20 psi.  What this likely means is that your head is not spraying as far as it should (ie a 15 foot nozzle may only reach 11-12 feet) and spray patterns within that arc may not be uniform.  This pattern of non-uniform spray distribution is common with rotor heads and what you will see here is a doughnut or bulls-eye pattern of green grass several feet out from the head with brown grass in between.  Resolving these issues is getting into an area where a lot more skill and experience is necessary.  Steps such as renozzling heads, moving or adding heads or splitting zones up may be necessary to improve the coverage.

Basic sprinkler system maintenance, part 2 - adjusting pop-up spray heads.

Adjusting rotor heads (the heads that turn shooting out a stream of water) is a little more complex than pop-up spray heads.  Depending on the head manufacturer head ajustment may be tool-less, require a specialized key (Hunter PGPs) or a small flat-head screw-driver (Rainbird 3500 & 5000 series).  For the sake of keeping this blog simple we will review how to check adjustment on Rainbird 3500s and 5000s.  I won't be going over nozzling these heads because it is way too easy to disrupt the precipitation pattern in a rotor zone unless you know what you're doing.  The selection of nozzles not only involves distance the water is thrown but also the arc of the rotor (ie a rotor in a 1/4 arc, 90 degrees, will cover the same patch of ground 4 times in the time a full circle rotor covers the ground around it once).

• First, turn on the rotor zone, either manually from the valve or from the controller.
• Walk up to the first rotor head and watch it.  What you are looking for is that the head is perpendicular to the ground and not leaning one way or another, the wiper seal at the base of the rotor is not blown and leaking, that the nozzle is still in the rotor, the stream is reaching adjacent heads (maintaining head to head coverage) and that the head returning after hitting the end of it's arc (ie-it's not hitting the end of it's arc and get stuck in the same position).
• Now that you have checked to see if it's still working correctly let's check the adjustment on the arc.  When the rotor hits the outside of it's arc on either side it should be edge of what that zone is watering, typically with these it will be the edge of the lawn.  if it isn't reaching the edge or is over watering into an adjacent area we are going to have to make some adjustments.
• With all rotor heads one side of the spray is fixed and the other side is the adjustable side.  In other words you will line up the fixed side, on Rainbird 3500/5000s this will be the left side, with the left edge of what you're watering.  This will be to the left from behind the rotor, the dry side.  You can accomplish this by taking a pair of channel locks, grabbing the barrel of the rotor below the top inch or so that has the nozzle in it and carefully turning it.  Now that you have the left edge set, take the small flat-head screwdriver and put it through hole in the rubber cap with the +/- symbols next to it and turn it to adjust the arc.  It only takes a slight twist of the screwdriver to adjust the arc several degrees.  I like to make a slight adjustment and either let the rotor turn or grab the top and swing it to each end of the arc to evaluate coverage.
• Repeat this on each head in the zone, checking for leaks and other damage.

Drip irrigation is pretty simple to check as long as it was installed well.  What you will be checking for is that there aren't any breaks in the drip line and visible emitters are working properly.

• Turn on the drip zone and you should hear air/water starting to spit out of the emitters.
• Walk the length of the drip line, looking for leaks where the line has been damaged or emitters pulled out of the drip line.
• As you're walking, check individual emitters to see if they're dripping, if they aren't replace the clogged emitter.
• Make sure the water is getting delivered where it should be, sometimes plants die or get moved.  If water is no longer needed remove the emitter and replace it with a 'goof plug.' Sometimes 1/4" 'spaghetti tube' gets caught up in a rake and ripped out, if an emitter isn't putting water anywhere near the plant that needs it cut an appropriate length of spaghetti tube and run it from the emitter to the plant.  Secure the lose end with a bug cap and stake or at least a landscape staple.

Voila! Your irrigation should be in pretty decent shape now and if you keep this up yearly your system and landscape will benefit from more uniform watering and less wasted water.  If it has been a really  long time (10+ years) since it's had a tune-up there are probably quite a few components that need replacing and heads moved you may need to get the services of a professional irrigation tech to help you out.

Basic sprinkler system maintenance, part 1 - adjusting pop-up spray heads.

You can improve the efficiency and coverage of your irrigation with a few minutes of time and just three tools.  This week I'll be covering the basics on how I get a spray zone (fixed sprays, not rotor heads) adjusted.

• First, grab a small flat-head screwdriver, hand pruners and a small shovel to straighten heads.
• Walk to your controller and start the first zone of your sprinkler system.
• As you're walking around the zone look for any leaks.  Large leaks such as broken pvc laterals will cause the pressure in the whole zone to drop and will be pretty obvious (look for the geyser).  But smaller leaks may go unnoticed for some time.  The most common are worn heads that are leaking around the stem and are caused by worn out riser seals.
• Check that each head is spraying where you want the water to go.  Obvious, I know but there a many systems I've worked on where spray heads are spraying out into the street or turned and watering an area another zone is covering.  Take a pair of channel lock pliers and grab the stem of the sprinkler and turn it (preferably clockwise) until the spray is pointed in the correct direction.
• Check each head to see if the spray is partially blocked, there is no spray at all, heads are sitting too low (the nozzle is barely clearing soil/grass/mulch), spray is getting blocked by plantings or heads are crooked.  Use flags, sticks, whatever you can find to mark each head that will need adjustment.
• The spray should be a nice uniform fan, if there are gaps sometimes you can dislodge the offending particle with a small wire poker, if the nozzle is totally blocked (ie- no or little spray coming out) check the small set screw on top of the nozzle to see if it is screwed all the way down shutting off flow, if it is back the screw out until the nozzle starts spraying. 
• Now if the nozzle still isn't spraying it means that has a total blockage and needs to be replaced.  Please note the numbers on top of the nozzle (ie- 8Q, 8H, 8F, 10Q, 10H, 10F, 12Q, 12 H, 12F, 15Q, 15H, 15F, SST, EST, CST, etc, etc) and replace it with the same nozzle.  This is very important!  If you replace it with a different nozzle you will either throw water where it shouldn't be (sidewalks, roads, onto your house) or you will not have full coverage and get brown spots in your turf.  Your local irrigation supply house will have every nozzle you will need; Home Depot will have a pretty limited selection of nozzles.
• If your nozzle was full of debris chances are that the head is sitting too low in the ground.  The top cap of the sprinkler should be level with the top of mulch or 1/4-1/2 inch below the top of sod.  Dig up the head until you have the whole head and a foot or so of the flex pipe below exposed and raise the head so it's sitting at the proper height and back-fill.
• Once you've gone through and replaced nozzles, raised/straightened the heads turn the zone back on and check to make sure you haven't missed any heads and they are all spraying in the correct direction.
• If there are heads that are buried in shrubs/perennials you can either prune some leaves/branches out of the way or if the head is really buried it may have to be moved out from behind the plant.
• Finally now that all the sprinkler heads have been straightened, moved, re-nozzled restart the zone from the controller and check to see if you're getting good coverage.  For lawn areas and areas with thick ground-covers this means total coverage, ie all spaces should be getting hit by at least 2 sprinklers.  Shrubs and perennials are a little more forgiving in that every square inch doesn't necessarily need to be getting hit, but each plant will need watering. 
• Coverage issues take a bit more expertise and I would recommend that you contact a professional to take a look at your system if the above steps don't get you to the point where you have good coverage.  There are many variables that could be causing a lack of coverage than a simple nozzle change won't fix at times from a change in water supply pressure, faulty valves, poor system design, or nozzles having been swapped out to ones with a higher flow causing a pressure drop.
• Congratulations!  You've finished tuning your first zone, now move on to the next zone of spray heads and repeat!