Watch Your Water!
As I see it, there are three main areas homeowners should focus on when designing a new landscape, retrofitting an existing one or simply making a few minor improvements to the irrigation system. The three areas of emphasis are: reduce the need for irrigation, irrigate wisely and use water more than once.
Probably the most important step to take when trying to minimize water use for irrigation is to plant only native or adaptive vegetation. Ideally, we want to get as close to a xeriscape condition as possible to reduce or even eliminate the need to use potable water for irrigation purposes. (Xeriscaping is an alternative approach to landscaping that emphasizes the use of drought-tolerant plants instead of turf to conserve water.)
One of the simplest ways to save water is to use plantings that require little or no water at all. There are attractive plants in every region, and they should be used as the foundation for any good landscape design. If you can’t xeriscape, try to complement your landscape design with water-stingy plants in order to improve water efficiency.
As much as possible, reduce or eliminate grass from your landscape. Grass does not make sense in many areas of the country, such as in the desert Southwest. Several municipalities around the country are offering cash rebates for removing grass from yards. The city of Las Vegas, Nev., for instance, currently offers homeowners one dollar for every square foot of turf grass they remove from a property.
If you live in an area that does not require irrigation for turf, then reduce watering as much as possible. Chances are you’ll have to live with some brown areas during extremely dry parts of the year, but you’ll still be able to enjoy your grass some of the time.
Mulching around the base of a plant will help to reduce water evaporation and can supply significant nutrients to the plant in times of stress. This is an inexpensive strategy that can be completed within a day or so.
In addition, use natural fertilizers and supplements instead of chemicals. All major home centers carry these products. Generally, they are no more expensive than non-natural options, and are easy to use.
For designs that require irrigation, use micro-irrigation technologies to apply water only where required, only when required and in only the amount required for optimal plant health. A micro-irrigation system can include common irrigation products like drip emitters, moisture sensors, and irrigation clocks or controllers.
Drip emitters deliver a specified amount of water to plants and come in various types. They can be carefully chosen to deliver one, five or more gallons of water per hour to selected plants, so these systems are very flexible. The homeowner simply has to select the proper emitter for a particular plant and then install the emitter at the chosen location. By using drip emitters, the evapotranspiration rate (the rate at which plants loose water through evaporation) is kept to a minimum, so water use is greatly reduced and water bills are correspondingly lowered.
At the beginning of each summer, check each drip emitter to ensure its proper operation. In many areas that have hard water, the emitters can become clogged and will cease to operate or will not deliver water at the specified amount. If the irrigation season has begun and this problem is not identified quickly, plantings can become damaged or even die.
There are several different types of irrigation controllers on the market, but the two most common are electromechanical and electronic.
Electromechanical controllers are driven by an electrically powered clock and use mechanical gears to activate the irrigation valves. These controllers are very reliable and not particularly sensitive to the quality of the power available. Power spikes, surges and brownouts do not normally affect the performance of the unit, and they will operate reliably for years. If a power outage does occur, generally the programmed schedule will not be lost, but delayed only for the duration of the power outage. These old reliables are readily available and cost less than more advanced electronic controllers, but features are limited, so you may want to consider a controller with more options.
Electronic controllers are operated by solid-state circuits that control the clock, memory and control functions. These controllers provide a large number of features at a relatively low cost and are very flexible. However, these systems are more susceptible to power failures than electromechanical controllers and will be affected by spikes, surges and brownouts.
I learned this the hard way after returning from a vacation during which a power surge occurred. My controller’s memory was completely blown, so I lost several plants. Others were damaged and struggle for life to this day. These controllers should be installed with electrical suppression devices and battery backup to ensure their reliable operation.
At a recent green building show I attended, I saw an interesting irrigation clock that receives data from weather satellites and controls irrigation water release based on humidity, storm conditions and other atmospheric data. This high-tech approach is certainly useful, but a homeowner would have to be technically gifted in order to stay on top of the electronics. If you enjoy electronic gadgetry, this is a great option for you.
Most controllers have a rain button that will override your pre-programmed watering cycle in the event of a rainstorm. Make sure you choose a unit with this feature, and learn how to use it.
Moisture sensors are an excellent upgrade if irrigation water is used. These units sense the amount of moisture in the soil and, much like an electrical light switch, will only close the loop and allow water to be delivered if the soil gets dry enough.
To me, it seems a shame to use potable water (water that is acceptable for human consumption) to irrigate landscape elements, especially when stormwater, municipally provided reclaimed water or graywater can be used instead.
Stormwater is a wonderful gift we can collect and use at our discretion. This strategy is as old as humanity itself, yet relatively few buildings have elements in place to collect and use stormwater. A 55-gallon drum or two connected to a home’s rain gutter is a simple solution that can be implemented easily and at a low cost. I’ve noticed that municipalities have started to offer these drums for purchase if you’re a resident, so check with your city to determine if such a program exists.
Many cities offer an opportunity to connect to their reclaimed-water line for irrigation purposes. Although usually an option only for new construction projects, it never hurts to investigate, so check with your city to see what types of programs are available.
Like the stormwater collection strategy mentioned above, the collection and use of graywater (the useable water that comes from sinks, showers and washing machines within the home) is a key strategy to be considered when attempting to reduce the use of potable water for irrigation. Graywater collection is most easily accomplished when the project is new construction, as separate drain lines need to be installed to direct the graywater to a holding tank, so it can be used for irrigation purposes. It is possible to retrofit an existing home for graywater use, but it can be more expensive.
Homes with crawl spaces or basements are obviously easier to retrofit than slab-on-grade buildings. The good news is that almost all of the water used within a typical home (except for toilet water and water used for food preparation) can be used as graywater.
Remember to use landscaping elements to improve the energy efficiency of your home whenever possible. Deciduous trees can be planted strategically to provide summer shade for those hot east- and west-side windows. When the trees loose their leaves in the fall, the warming sun can shine on through all winter long.
On a final note, when it comes to revamping your irrigation strategy, just do what you can. You will probably not be able to implement all of the ideas I’ve mentioned here immediately, but they are all effective ways to save water, and can be applied in a step-by-step manner. For now, do what you can afford to do, both financially and time-wise, and implement the rest when you can — hopefully before next spring, as many of these strategies will free you up from being a slave to your landscape during the summer, allowing you to spend more time with friends and family. So complete your irrigation analysis soon, while there’s time to enjoy the rest of the summer.
Charlie Popeck is the president of Green Ideas Environmental Building Consultants and a contributing editor to Smart HomeOwner. He can be reached at 877-887-9799 or Charlie@Egreenideas.com. Green Ideas specializes in helping design, construction and facility management teams understand and implement building science and sustainability into their projects.