“Imagine a day without water.” That’s what organizations across our country are asking us to do this Thursday. The purpose is to highlight how water is essential, valuable and in need of investment. But many Texans don’t need to imagine a day without water. Odds are they already lived through at least one day without water this year.
February’s winter storm calamities are well documented. Extreme cold temperatures, combined with ice and snow, wreaked havoc on the electric grid and water supply systems. Millions went days without running water. For some, a day (or days) without water was, at best, an exercise in discomfort – while for others a newfound misery in the darkness and cold.
Despite this experience, Texans still need to imagine a day without water in our future. Our state faces the perpetual question of whether we will have enough water to serve a growing, thirsty state. Ac- cording to the 2022 State Water Plan, Texas faces a long-term water deficit where, in 50 years, our water demands will outstrip available supplies during a drought.
In the meantime, nature will not help. Recently, Texas 2036 and the Office of the State Climatologist released an extreme weather report with a 15-year outlook that raises further concerns about the availability of future water supplies. First, the average Texas temperature will be three degrees warmer than those from the last half of the 20th century.
Warmer temperatures mean less water in lakes, rivers, and reservoirs. Specifically, rising temperatures could cause 4% more surface water loss during the summertime in 2036 than in 2000-2018.
Then comes the issue of drought. Data suggests that Texas will continue to experience precipitation variability. The best illustration of this variability comes from ten years ago. Throughout 2010, rainfall kept drought conditions at bay so that by October, according to the US Drought Monitor, only 9.5% of the state was in drought.
Then the rain stopped.
2011 was the worst one-year drought in the state’s recorded history. By October 2011, 100% of Texas was in drought, with nearly 92% of the state in the severe to exceptional drought category.
Our research concludes that this rainfall variability will continue, which means we may anticipate droughts or even multidecadal megadroughts observed in paleoclimatic records. Regardless, future droughts will be worse owing to increased temperatures and higher rates of surface water evaporation.
The upshot here is that we have time to adjust how we plan for water supply projects so that we can avoid a day without water.
First, Texas can include extreme weather data and trends into water supply planning projections. While our current State Water Plan observes that sedimentation will diminish available future water supplies, evaporative losses are not taken into account. Updating the water planning framework to include extreme weather impacts, namely hotter heat and drying lakes, is a reasonable step.
Further, state and regional planners should prioritize new water supply strategies that are resilient to heat and evaporation. According to the Water Plan, surface water resources, including reservoirs, will provide 37% of new water supplies by 2070. If heating and evaporative trends continue past 2036, then these supply strategies may yield less water than anticipated. Other drought-resilient strategies, including water reuse, aquifer storage and recovery, conservation, and desalination may be the more effective strategies moving forward.
Reliable water supplies are essential for living in our homes. Since extreme weather trends indicate that Texas may have less water available in our future, we should change our thinking to ensure state water planning and supply development policies do not relegate future generations to the fate we endured in February.
This piece was originally published by the Austin American-Statesman on October 21, 2021.