April 20, 2009
In-ground lawn sprinklers are about 50% efficient. Evaporation, poor maintenance and bad design are the largest impact to that figure.
The spring season has many of us looking to use automatic lawn sprinklers to do our watering. Hopefully you have read my post on Chasing Lawn Sprinkler Leaks. This is a good start, but it just barely touches the subject of efficiency. Besides fixing leaks, there are numerous items that can be performed to make your system more efficient without sacrificing performance. Today, the dollar cost of water is still very reasonable, however water conservantion is really about using less and the long-term benefit. Even though this article will address issues specifically related to systems designed with pop-up type heads, many of the suggestions will work with other types as well.
General Design Considerations: Understanding how an irrigation system is engineered will help you understand how to make one work more efficiently. If you have a “blueprint” of your system you have a head start, if not, we will perform some hands-on analysis to obtain performance information.
- Elements of Design: All systems are designed based on water usage and gallons of water (GPM) per minutes used by each head. Typically the small pop-up heads use more water per head per square foot watered. Because they apply more water per square foot than other types, they work well for small and medium-sized residential properties. They can also be easily tuned to fit odd spaces with a host of nozzle choices.
- Zones or Sections: All sprinkler systems are broken down into zones or sections. The Irrigator calculates the zone size by using available water pressure, pipe size and maximum GPM per zone. Besides these items, zone adjustments may also include special watering needs such as side yards, gardens, flower beds or odd-shaped areas. Since additional zones require more material, labor and money many Irrigators will keep the costs down by limiting the number of zones installed, this is good for him and maybe not so good for you. As you analyze your system and you see one head out all by itself in the middle of another zone, the Irrigator needed a head in that location but did not have enough water budget left in the prevailing zone. This is all very common but can be problematic if you are attempting to manage your water usage at a higher degree than normal homeowners.
- Sprinkler Heads & Nozzles: There are a half a dozen types of sprinkler heads, but the pop-up style is still the most popular because they can meet varying needs. Pop-ups can be purchased in different levels of spray coverage and are promoted as providing better coverage because they are typically spaced closer together. Typical systems use heads designed with 10′, 12′ and 15′ radius spray patterns as well as strip sprays and bubblers. Larger properties can use Impulse or Rotary style heads to conserve water as they can be placed very far apart. Because they distribute water in more of a stream vs. spray found with a pop-up style, they do not waste quite as much water per square foot. Impulse and Rotary heads work well with wide open lots, but don’t work well when there are obstructions such as building structures, trees, and property lines.
- Mixing Head Types: No matter the sprinkler head style, it is perfectly normal to find a mix of spray pattern nozzles within each zone, and a mixtures of head types in a system, but NOT a mixture of head type (Pop-up, Rotary, Orbital) in the same zone. Mixing head type can make it difficult to properly manage coverage and watering levels.
- Optimal Design: The best designed systems account for the water required based on the environment. In other words, shrubs and flowers should be watered at a different rate than turf. Shaded turf may be watered less than turf placed in full sun. Grass type is also influential. Unfortunately, not all sprinkler systems are designed with these considerations as it can be more costly to engineer a system with greater efficiency. TIP: If you don’t currently have a sprinkler system, and are looking to purchase one, beware of the very low bids as some Irrigation Contractors will take short cuts on the items mentioned in an effort to win the business.
Stage I: Gain the most efficiency out of your existing system without impacting the design. All of Stage I is covered in detail in the “Sprinkler Leak” post. But here are the high points.
- Check for leaks in the pressure side of the system. Use your water meter to isolate the leaks in the sprinkler zones.
- Check for leaks in each zone. Most leaks are at the heads; repair and replace the heads and risers as necessary. Make sure you use the same style head and similar nozzle sizes as the one you are replacing. TIP: All the major manufacturers make pop-up heads, its okay to mix brands but if you stick with the same brand, you can always move and change nozzles between existing heads when needed because nozzles are not universal between manufacturers.
- Ensure all sprinkler heads are clean and providing the proper water pattern.
- Adjust the watering duration and times to match the season.
- If your watering durations continue to allow excessive water run off, try changing the watering times to a series of short cycles. For instance, change a single 15 minute cycle to 3 back-to-back 4 or 5 minute cycles. This can allow the water to saturate before the second and third cycle occurs. Typically, I don’t like the short cycle watering strategy, but if you perform it back-to-back, its okay.
- Consider using your system in manual mode only. Watering when only necessary will reduce your water usage substantially.
Stage II: Plan to get wet. This stage requires a bit more effort and the gains achieved may be small, but the intent is to make gradual changes that will increase efficiency without negatively effecting performance. This stage is intended to optimize the system by fine tuning the existing sprinkler heads.
- Look for excessive water accumulation. Not all landscapes require the same amount of water. Unfortunately, when irrigation systems are designed, this fact may not be included in the design. Read the system performance by looking for items such as excessive water, green moss or over saturated ground and plants.
- Fine tune individual sprinkler nozzles. Each sprinkler nozzle has a fine tuning screw on the top of the nozzle allowing you to change the water output. However, when you reduce the flow, you reduce the pattern spray coverage. In some cases, you may completely turn the water off at the nozzle. This is sort of a trial and error exercise, so you may need to make the adjustment and keep an eye on the area for proper coverage. Newer style nozzles may include a water saver disk found under the nozzle to equalize pressure and reduce water usage. Adding or removing this disk will also change the amount of water delivered.
- Parkway Watering: I mention this because this strip of grass found with many older homes is a large source of water waste with automatic lawn sprinklers. Run the zone that waters this area to determine how much waste is occurring. Adjust it as much as you can. If you still have excessive water run off you may consider adjusting the fine tune screw to the off position and either hand water it or let it go brown and just let the rain keep it green By completing Stage I & II, you should be reducing you water waste. You may be able to reduce your watering duration by the fact that you are wasting less water. Before you move to the next step, let the system run for several weeks/months. Monitor the performance and make further adjustments as necessary to the nozzles and watering duration.
After completing Stage I and II let the system run for a couple of months. Monitor the performance and the water usage, make adjustments as necessary. However, if you want to go further, I still have Stage III and IV recommendations. Look for my post next week on “Lawn Sprinkler Efficiency Upgrades Part II“.
Stay up to date on the latest HomeownerBOB articles by signing up for the email subscription.
March 7, 2009
SPRING HAS SPRUNG!! Okay not everywhere. Here in my part of the country the daffodils have been out for about 4weeks. Yep, it got here early, so if your local temperatures are above freezing and the trees are starting to bud, it’s time to move forward… its inevitable. It’s time to fix all those items that broke during the winter months, repair the items that have deteriorated over the last few months and perform a little preventative maintenance around the house. This seasonal reminder provides a list of items you need to review before the summer months set in. If you need details on what to look for or what to do, click on the link (if there is one) and it will take you to the post that was written on the subject and provide more detail.
- Heating/Cooling-Air Filters: Assuming you have a forced air system, change the filter prior to the heavy air conditioning months.
- Roofing-Looking For Leaks: Spring rains are approaching so inspect your roof for leaks, trim away any tree limbs and clean debris off the roof. Look for raised nails and any breaches in the roof surface.
- HVAC Outdoor Unit: Get your garden trimmers out and trim away any vines or growth away from the outside condenser. You should have 18″ to 2 feet clearance around the unit. Also take your water hose and wash down the outside coils that may have accumulated dirt. Check the condensation drain that comes from the air handler in the house. Ensure that it is clear of obstacles or debris by pouring water through it.
- Water Leaks: Check all water fixtures and toilets for leaks. Inspect fixture drains for water puddles or loose joints in the traps.
- Lawn Sprinklers: Exercise the system. Look for excessive water traveling down the driveway or sidewalks. Inspect the sprinkler heads, look for blow-by and odd spray patterns. Replace or repair the heads.
- Exterior Inspection: Walk around the house, look for rotted wood, peeling paint and other exposed surfaces. Use caulk to re-seal cracks and touch up paint to reseal the surfaces. Replace rotten wood as necessary.
- Interior Inspection: Winter dry-out will have caused some surface cracks around doorways and windows. Also re-caulk/grout any cracks that may have surfaced in the bathroom and kitchen, especially around the tub and shower. These two areas experience the most use and require the most maintenance. Replace or clean water filters, faucet strainers and vent-a-hood filters in the kitchen. Flush kitchen and bathroom sinks with scalding hot water for approximately 3-5 minutes.
- Water Heaters: Tank type water heaters should have their pressure release valve tested (opened and closed). This will also validate the the drain pipe is clear and open.
- Gutters and Downspouts: Clean you gutters of leaves and debris. Flush them with water to ensure they flow freely.
- Surface Water Drainage: Culverts, waterways, landscape drainage systems should be cleared of debris and overgrowth that may have occurred.
- Windows and doors: Look at the edges where the windows and doors connect to the house. Ensure the caulk is in good shape and add caulk as necessary, indoors and outdoors.
- Electrical Service: Inspect the Entrance, Mast and Weather-head. Look for any damage that may have occurred over the winter. Look for tree limbs that may be contacting the entrance cable.
- Electrical Service-Smoke Detectors: Clean your smoke detectors of cob webs and change the battery.
- Test your security system: Work with monitoring service to validate all the door, window, glass break, and motion sensors operate properly.
If you are needing some additional information on one of the topics that I have not written about, let me know and I will put it higher on the list of articles to write. Email to HomeownerBOB@gmail.com
February 28, 2009
Common water pressure should be somewhere between 45 and 125 psi.
There are many contributing factors that impact this value that may include 1) distances to the water source, 2) size of the distribution lines, 3) elevation of the water supply, 4) primary water line size and the list goes on. However, your plumbing system should work correctly if the pressure is within the 45/125 psi range. If you have just moved from the city to a rural area, do not be surprised if the water pressure is lower than what you have been used to. Contact your water provider to determine if they are within their specification at your house. (If your house is served by your own well, the primary pump will determine the pressure. Wells will be covered as a separate post.) There is no maintenance inspection associated with the water pressure item other than knowing what it is as a reference as it can cause the system to act differently than normal. Recognizing the changes will help to determine if any action is required during high pressure conditions, you may experience excessively noisy pipes, clanging or hammering. Low pressure is pretty obvious… low pressure and low flow. Typically, these conditions can be associated with the service provider performing work that required them to open up or turn off the water near by. If the condition does not pass in 24 hours, you may call them to determine how long the condition could continue. TIP: If you experience low pressure, take the opportunity to fill up some gallon jugs as you may totally loose water pressure before the water line repair is fixed.
If you suspect your water pressure to be out of range, you can check it using an inexpensive pressure gauge available at most any home improvement center. To check your water pressure, simply screw the pressure gauge on to an outside faucet (TIP: closest to the water meter) and open the faucet. This will provide an accurate reading. If you find it to be low or high and intend to call the water department, provide them the reading to assist them in their resolution. (TIP: Knowing what the water pressure is, under normal conditions, is also valuable information)
Since water lines stay under pressure and are considered a closed system, turning the water off, opening the pipes(s) and exposing the interior of the water line allows dirt and mud into the system. It doesn’t matter whether the work is performed by the water provider, plumber or yourself, it can cause clogged water filters, strainers and faucet nozzles. If you are aware of the work, wait about three days, then clean your faucet strainers/nozzles/filters. Look for a future post on this subject. Plumbing-Faucets.
January 21, 2009
Uninsulated pipes installed in unconditioned crawl spaces or attics can freeze when the outside ambient temperature falls to 20F or below.
I am a little late in the season for this one, but here in the Southwest part of the country, winterizing our plumbing is perceived as not a big deal, but in reality, we have more frozen pipes in our part of the country than Northern climates. Our building code are more lenient and allow methods that would never be considered in Michigan or Wisconsin. Several years ago, Southern Louisiana had extreme cold weather over the Christmas holidays. The amount of broken water pipes almost called out the National Guard, due to the extreme loss of water pressure in the city water supply. If you live in Baton Rouge or Houston, it would not be uncommon to find your main water pipe exposed on the outside wall of the house before it goes in the house. For that reason, these tips may apply to homeowners that live in zones 8A or greater as defined by the USADA Hardiness Zone Map.
According to the Building Research Council at the University of Illinois, uninsulated pipes installed in unconditioned crawl spaces or attics can freeze when the outside ambient temperature falls to 20F or below. However, high winds or “wind chill “can augment this number potentially causing frozen pipes at higher temperatures. Wind chill typically impacts pipes that may be exposed to insulation leaks in the building envelope. For example, a water pipe in an exterior wall without insulation is at risk, add the fact that a crack in the exterior wall near the pipe will allow colder temperatures to increase the opportunity for a frozen pipe.
Key Inspection Points and Action Items:
- Wrap exposed pipes: Especially outside pipes, but don’t forget pipes under the house in crawl spaces as well as in the attic. All Home Centers sell foam sleeves to cover the pipes. This is cheap insurance as these sleeve are about $2.00 per 8 feet.
- Cover or wrap the exterior faucets. Home Centers have a solution for faucets that protrude from the wall, but you will have to be creative for faucets that surface out of the ground. My grandmother always tied an old hand towel around the outside faucets…. its pretty ugly but it worked.
- Caulk the cracks: Check the exterior of the house, especially in relation to faucets or pipes on exterior walls. Ensure the surface is well sealed as not to allow cold air to seep into the wall cavity.
- Open cabinet doors: In extreme conditions or extended vacations, open cabinet doors associated with all kitchen and bathroom faucets.
- Dripping Faucets: If it appears you may experience sub 20 degree weather, and you have pipes (especially on the North side) that are at risk, let the hot and cold water run. Granted, this breaks my rule of wasting water, but if possible, try to capture the water in a pan or pail and water your house plants. They are probably drying out since your are running your heater anyway. TIP: If the open faucets stops dripping, leave it open as this will allow the ice formation to expand without damaging the pipes.
- Turn off and drain Lawn Sprinkler System: If cold weather conditions are forecasted for several days, you may consider turning off and draining your sprinkler system. Hopefully you have a cut off and drain. For some of us, watering in the winter is still necessary due to the lack of rain or snow, so you may just turn it off based on the weather forcast. TIP: If you do not have a drain at the sprinkler cut-off, you can activate the sprinkler system for a few seconds to remove presure from the lines.
- Disconnect and drain exterior water hoses: A water hose connected to an exterior faucet will telegraph a frozen condition into the faucet potentially causing the faucet to freeze.
- Extended vacation:If you are leaving the house for several months, you may consider turning the water off and draining the pipes. As an alternative to that, leaving your Central Heater on 60F, will alleviate this situation. Look for future posts on “Extended Winter Vacations” for more details.
January 14, 2009
The city provides a water meter to determine how much to charge for water usage and also a place to turn the water off. The meter can also be used as a tool to recognize water leaks. If your water bill dramatically changes and cannot be related to service work, changes in household routines, extra house guests or summer watering, the water meter should be the place to start to determine if there are any hidden water leaks. Obviously, if you have any recognizable leaky faucets, fixtures or toilets, these leaks should be addressed. $TIP$: Many municipalities charge related services (sewage, trash pickup) on the same bill, these charges can be relational to total water usage. If you have leaks you may be giving the city extra money due to a water leak. Look for the upcoming post on Chasing Water Leaks for a leak isolation method.