According to the San Antonio Water System (SAWS) a typical commercial irrigation system uses on average 20,000 gallons of water per use. A poorly maintained, leaky system can triple that figure.
In a San Antonio Express-News interview about the ongoing drought, SAWS Conservation Director Karen Guz noted in that in 2011, the turf covered medians within the Stone Oak area, north of San Antonio, consumed 30 million gallons of water outdoors for irrigation. In contrast, in the same general area, North Central Baptist Hospital used 28 million gallons indoors.
When the City of San Antonio was flirting with stage three drought restrictions last summer, restricting landscape watering to once every other week, Guz revealed that 70 to 100 million gallons of water were being used by San Antonio residents each day on landscaping.
The Texas Water Development Board estimates that 40 percent of all municipal water use is outdoors. Of that, half is lost to runoff from the excessive watering of lawns.
This is drinking water that is simply wasted. This is water that could easily be conserved.
The 20,000 gallon system pictured above includes the filters and sanitation equipment that provide all of the drinking water needed for family of three who built their modern home near Bergheim, eliminating the need to drill a well. Despite two years of drought, the system averages 75% of full capacity. As the landscape is appropriate for the area—native turf and drought resistant plants, virtually no water is used outdoors.
Some may be thinking: I pay good money for my water, why should I care how much I use or if some of it is wasted?
San Antonio is dependent on a sole-source aquifer—the Edwards Aquifer. In order to comply with Federal law, limits have been placed on how much water can be withdrawn. To meet the water needs of this rapidly growing city, SAWS develops water from other sources.
Using water from other sources and wasting it outdoors is done at the expense of others—ultimately it strains the availability of drinking water of others.
The same areas began receiving surface water from Canyon Reservoir in 2007. SAWS customers in northwest San Antonio began receiving water from this source in 2006.
Non-Edwards sources like these are increasingly being exposed to the demands of the rapidly growing regional population in counties surrounding San Antonio such as western Comal and Kendall where rural residents have few, if any, alternate sources of water.
Whether it is taking personal responsibility for one’s water supply for a life in the Hill Country or changing the way one uses it in a city like San Antonio, we should consider that we are all part of the water cycle—all water is being used by something at some time.
Both our ground and surface water supplies originate with the first drop rain that falls on the land which in turn is captured by complex, large-scale ecological processes involving many variables including plants, animals, soils and geology.
When these natural processes function optimally our aquifers are replenished, springs flow, rivers run and lakes fill. When we reduce our water waste there’s more left not only for our enjoyment and consumption, but for the needs of all living things.
Remember that water conservation in times of plenty is just as prudent as it would be when it is in short supply. By changing the way we use water today, we may very well avoid having to make the choice between water for thirsty lawns or thirsty people tomorrow.
Milan J. Michalec is a Director on the Cow Creek Groundwater Conservation District in Kendall County and the 2013 President of the Hill Country Alliance, a non-profit organization dedicated to education, conservation and cooperation throughout the Texas Hill Country.