As Record Demand and Heat-Waves Loom, Texans Must Stop Over-Irrigating
Two times per week is more than enough for North Texas lawns As Texas emerges from a winter of deep-frozen quarantine and our western neighbors descend into a cauldron of drought and heat, the prospect of a green lawn outside our window feels unusually comforting. Before you greet the July sun with a full blast of irrigation, however, it’s worth remembering healthy lawns don’t need nearly as much water as you think.
In a year and era of truly wicked problems, watering wisely is a remarkably simple way for North Texas to address our deepening water crisis. Irrigating no more than twice per week is not only more than enough to keep lawns healthy, it will go a long way towards ensuring a resilient future water supply for North Texas.
Make no mistake, the over-irrigation of our proliferating lawns is a predicament worthy of the 2020s.
Landscape irrigation is the single-largest component of municipal water use in Texas—a reality largely obscured from the ground-level view of most North Texas homeowners. More than a quarter of all Texans live in North Texas and, in a staggering projection, the Texas Water Development Board anticipates the region’s population will double by 2070. This growth coincides with the predictions for hotter, drier decades of megadroughts. It’s a recipe for a water disaster that’s already underway. If our booming population continues to water its lawns without regard to conservation, we’ll face a water crunch that no amount of engineering and policy acrobatics can overcome.
The strain of satisfying unattainable water demand related to landscape irrigation will stretch our already over-burdened state and city decision-makers, utilities, and budgets to a breaking point. Additional water supplies are not cheap nor easy to come by. The groups that most suffer will disadvantaged lower-income households hit hardest by rising water prices—not to mention the wealth of fish and wildlife that depend on healthy flowing water in Texas.
Fortunately, unlike so many problems in our plagued times, there is a straightforward, solution to ease North Texas’ water supply challenges: we simply don’t need to water our lawns nearly as much as we currently do. In fact, according to researchers from the Texas A&M AgriLife and Research Center at Dallas, if we map the growth cycle of warm-season turf grasses to precipitation patterns for the DFW area, lawns with appropriately-chosen turfgrass varieties only need supplemental irrigation between June and September in a typical year. Yes, that’s right, choose the right variety of grass, and on average you’ll only need to turn on your sprinklers four months out of the year.
Furthermore, during those peak summer months, most turfgrasses only require minimal supplemental watering—an amount that can easily be met by watering once or, at most, twice a week. Overly-frequent watering creates what Texas A&M’s Dr. Rebecca Grubbs-Bowling calls a “codependent turf baby,”—a lawn that comes to expect your daily splash of water and thus never develops the deep, hardy roots it’s perfectly capable of growing. In contrast, less frequent irrigation gives time for top-soil to dry out, motivating your turf to grow deeper to find water that’s percolated further down. Deeper roots offer numerous benefits to your turfgrass from improved drought- and cold-tolerance to resilience in the face of common lawn pests like disease and weeds. Once or twice-per-week is thus not only a critical water conservation measure, it’s much better for your lawn.
With decades of research now in hand, the challenge moving forward is two-fold. First, those North Texas water utilities who have yet to adopt twice-per-week (at most) ordinances need to get on board. A recent survey of the region’s utilities reveals the implementation of watering schedules is uneven. While 62% of the region’s population is covered by twice-per-week ordinances, a full 70% of utilities have no limit on watering at all. If we want to make progress on ensuring a resilient water supply for North Texas, we need to get all utilities, big and small, to prioritize permanent no more than twice-per-week outdoor watering ordinances. Every single utility in North Texas has a role to play.
Utilities need considerable support in making this shift. Fortunately, targeted resources are increasingly available to them. This past fall, for example, a consortium of North Texas water utilities and conservation specialists held a first-ever summit to speak to the reasons for and ways to implement twice-per-week watering schedules. Decision-makers and utilities thus learned directly from peers how best to develop and implement effective watering ordinances, a learning format the consortium hopes to expand and repeat in coming years.
In a further sign that twice-per-week is now the consensus approach for the region, North Texas’ Region C Water Planning Group formally approved the 2021 Region C Water Plan in October 2020. This 50-year water supply plan for the 15-county region explicitly recommends no more than twice-per-week outdoor watering as a water management strategy. In fact, the plan concludes a shift to twice-weekly irrigation alone would bring a 3% reduction in total water-use, enabling communities to reduce their projected unmet water needs by at least 60%. The recommendation of the twice-weekly approach in the final 2021 Region C Water Plan makes clear water conservation is a growing and important water supply strategy for North Texas.
Our second challenge is bigger and more personal. We each need to truly understand that twice-per-week is more than enough to maintain our beautiful North Texas landscapes and adjust watering practices accordingly.
Our utilities can only do so much. If ever there was a time for us to show our Texas-bred love for common-sense and self-governance, it’s right now. Our beloved state is entering a bit of a dry patch. Let’s turn off the sprinkler more often and let our landscape take better root. The future water supply of North Texas depends on it.