The Art of Wasting Water with Drip Irrigation

When properly designed, drip can be the most efficient method of irrigation. But when installed incorrectly, drip can use as much water as ordinary sprinklers, if not more.

You’d be surprised just how much water can be wasted with bad drip irrigation. By its very nature, drip is simple to lay out and simple to operate: supply lines laid on top of the ground with emitters to release water precisely where it’s needed. When properly designed, drip can be the most efficient method of irrigation, delivering a steady stream of moisture directly into the roots of plants.

There are also plenty of ways to install it wrong: bizarre piles of overlapping, tangled drip tubes spaced too close together, and drip lines in rigid geometric patterns where nothing is growing.

Poorly designed drip systems can use as much, or many times more, water as ordinary sprinklers. SAWS irrigation rebates suggest drip deliver a half-inch of water per week with 18-inch tube spacing and individual emitters rated .6 gallons per hour.

Drip runs longer than other irrigation types — 45-60-minute run times are not uncommon. What the pictures don’t show is that many of the featured drip systems were set to water every day. It’s a common misperception that drip should run three times a week, or every day.

Remember, in a single cycle drip delivers a week’s worth of water to established perennials. There’s no need to run it every day.

Ideal Drip Irrigation w/ Inline Tubes:
Tubes: .6 gallons per hour, 18 inches between emitters
Spacing: 18 inches between tubes
Water: ½ inch per week
Precipitation rate: .43 inches per hour

    1. Drip is an odd choice for native plants. Once established, native trees, shrubs, grasses and perennials can grow on their own without irrigation.


    1. A concrete lamp post needs no irrigation at all. In this case the extra tubing could have easily been left out.


    1. Empty landscape beds don’t need water either, extra tubing just creates more opportunities for leaks like this. Inspect drip for leaks at least once a year.


    1. In-line drip tubing emits water out of regularly spaced emitters. Obviously, it should only be used where plants are growing.


    1. Drip is designed to deliver one-half inch of water per week. A deep-rooted tree like this will never need it.


    1. Here, drip was used in a landscape composed entirely of native wildflowers — where no irrigation was needed at all.


    1. These drip lines have been spaced at 6-inch intervals. Properly spaced drip lines should be laid at 18- or 24-inch intervals.


    1. This in-line drip tubing delivers 20 gallons of water per minute to a gravel bed without any plant materials.


    1. A huge spider web of drip tubing would be expensive to install and maintain. Actually running it might cost far more.


    1. A bubbler would have been a much more efficient means of watering this root ball.


    1. Running drip too long will inevitably drown plants.


    1. It doesn’t matter how much water is applied to concrete, it simply won’t grow.


    1. Here, drip was used to irrigate an air conditioning condenser.


    1. Yet another case of watering a concrete lamp post. Again, the extra tubing could have easily been left out.


    1. An entire landscape of native plants was drowned by excessive drip irrigation.


    1. Texas bluebonnets don’t care where they grow; the drip isn’t helping.


    1. Yucca needs no irrigation.


    1. SAWS offers an irrigation rebate to remove unnecessary drip irrigation.


    1. Drip is never needed to grow river rock.


    1. Proper 24-inch spacing.


    1. What’s the proper spacing of drip in areas without plants? None. Areas devoid of plants don’t need irrigation. Period.

Picture of Brad Wier
Brad Wier
Brad Wier is a SAWS conservation planner. Years in South Texas landscaping and public horticulture gave him a lasting enthusiasm for native plants that don’t die when sprinklers -- and gardeners -- break down. He’d rather save time and water for kayaking and tubing. He is a former kilt model, and hears hummingbirds.
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