Water-Saving Irrigation Strategies
By: Laura Fisher Kaiser
Rainwater can be collected in a rain barrel, which has a spigot to connect your hose.
Almost one-third of the water your family uses—some 100 gallons a day on average—ends up on your yard and garden, according to the Environmental Protection Agency. Nationwide, more than 7 billion gallons a day go to landscape irrigation. If that weren’t problem enough, as much as half that water is wasted. It falls on sidewalks or evaporates into the air before it ever reaches the ground. With a few simple changes to the way you water, you can save a precious resource and lower your bills at the same time. To remember the steps to take, just use our handy acronym: DIRTS, which stands for drip irrigation, recapture, timers, and sensors.
Drip irrigation sends water only where you need it
Drip irrigation systems can be a great way to save because they put water only where you want it. Unlike a soaker hose, which emits water all along its length, a drip system delivers water directly to plants’ roots, which cuts down on waste and also reduces weeds.
A drip system is basically a long, thin plastic tube sitting on the ground or, less often, buried right below the surface. Small fittings, called emitters, release water at rates of one-half to four gallons an hour. The tubing is attached to your outside faucet with a valve. You can turn on the drip manually or put it on a timer. Some systems also let you adjust the water flow, which can help prevent overwatering.
Installing a drip system is pretty easy. Attach the valve, run the tubing, and insert the emitters where you want water. The number of emitters you need depends on what you’re watering. A 10-foot tree that soaks up 60 gallons of water a week might need several emitters, while a small plant that only requires a couple of gallons would need just one.
A new drip system will cost about anywhere from $50 for about 20 plants to $200 or more for a whole yard. You can also convert your existing in-ground sprinkler system. Companies like RainBird make adapters that let you replace sprinkler heads with connectors for drip tubing. Going from sprinklers to drip irrigation can cut lawn water use by up to 50%, saving you about $70 off the average annual household water bill of $475.
Recapturing rainwater lets you irrigate for free
Plants love the purity of rainwater, and you can’t beat the price. One inch of rain on a 1,000-square-foot roof provides 600 gallons of runoff. Depending on your local rainfall, that could be enough to water your plants all summer.
All you need to harvest rainwater is a simple plastic or wooden drum with a spigot near the bottom where you can attach your hose. A 60-gallon model will set you back $75 to $150.
Just put the barrel underneath a downspout to catch rainwater coming off the roof. You’ll need to attach a flexible elbow to the downspout so it feeds into the barrel. In areas of heavy rainfall, you can expand your storage capacity with $10 connectors that let water flow from one barrel to another.
A few cautions. Roofs made of asbestos shingles, treated cedar shakes, or old tar and gravel aren’t good candidates for rainwater collection because the runoff may contain high levels of contaminants. To keep debris out and pests away, especially mosquitoes, cover your barrel with a fine mesh screen or lid. If you have kids, clamp the lid down to keep them from falling in.
Timers and sensors keep water waste to a minimum
Whatever watering system you choose, putting a timer on it will make your watering more efficient. Plus, if you live in a drought-prone area where watering schedules are restricted, a timer can keep you from getting a ticket.
Timer kits range from simple $20 dial models that screw onto the faucet and let you set on and off times manually to electronic controllers that let you program multiple on-off times and different watering schedules for different days of the week. If you want to track your water use, you can add a garden water meter for less than $10.
For even greater water savings, you need a sensor ($20-$30) that adjusts the water flow depending on how much rain you’ve had. These sensors measure either actual rainfall or the moisture in the soil, then automatically subtract that amount from the next watering cycle. Savings can be significant: A University of Florida study showed that soil moisture monitors can cut water use by more than 50%.
You can even give your water monitoring a high-tech spin with an ET (evapotranspiration) controller. These “smart” controllers use real-time satellite weather data to make watering adjustments. They can also be programmed to adjust for soil type, weather conditions, and slope. Installation requires a professional, but savings can be 20% to 40%, according to the Irrigation Association. Many water agencies in the West give rebates to customers who install “smart” systems; in southern California, installing an ET controller qualifies you for a $200 rebate.
Laura Fisher Kaiser is a contributing editor to Interior Design magazine and a former editor at This Old House Magazine. The secret to her Washington, D.C., garden is blood, sweat, tears, and mosquito repellent.
Used with permission of the NATIONAL ASSOCIATION OF REALTORS®. Copyright 2010.
All rights reserved.