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Falling Behind

Water Planners Focus on a More Populous Texas, but Not a Hotter One

As state water planners prepare to spend $2 billion in public funds to address Texas’ water needs in the coming decades, scientists say state leaders' skepticism on climate change will only impair such planning.

By Neena Satija, The Texas Tribune and Reveal
Scientists say higher temperatures due to global warming are already diminishing water resources, and that climate change will cause the southern and western portions of the state to become drier. Those regions supply water for fast-growing cities like Austin, San Antonio and Dallas, as well as the Rio Grande Valley.

Falling Behind

Falling Behind is a 10-part series on the flip side of state leaders’ aggressive pursuit of the "Texas Miracle.” You can also read our related Hurting For Work series here, or subscribe to our water and education newsletters here.

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After Texans overwhelmingly approved spending $2 billion in public funds on new water infrastructure projects last November, Republicans and Democrats alike hailed the state’s ability to solve its water woes in the wake of explosive growth and debilitating drought.

But as state water planners prepare to spend that money and address Texas’ water needs in the coming decades, they are only planning for a bigger Texas — not a hotter one. Scientists say Texas Republican leaders’ aversion to reducing the state's economic dependency on carbon-polluting fossil fuels — and their reluctance to acknowledge climate change — prevent the state from properly planning for the impacts of a warming planet on natural resources crucial to its growing population.

“Climate change will affect water supply by 5 to 15 percent in the next 50 years,” said John Nielsen-Gammon, the state climatologist and a professor at Texas A&M University. “I don’t think [the effects] are small enough to ignore.”

Nielsen-Gammon and other scientists say higher temperatures due to global warming are already diminishing water resources, and that climate change will cause the southern and western portions of the state to become drier. Those regions supply water for fast-growing cities like Austin and San Antonio, as well as the Rio Grande Valley.

The Texas Water Development Board “does not have an official position on climate change,” said Robert Mace, deputy executive administrator of the agency. Nor does it consult with climate scientists on their long-term projections. Instead, the agency plans for how a larger population might deal with a repeat of the worst drought recorded in Texas history — considered the multiyear drought of the 1950s. 

That means the water board does not take into account that the state is at least one degree Fahrenheit hotter on average than it was 20 years ago, significantly exacerbating the drought gripping Texas. Because of higher temperatures, soil is often so dry it sucks up excess rainfall before that water runs off into rivers and reservoirs, and more water evaporates into the atmosphere. That trend is expected to continue, climate scientists say, and needs to be a part of the conversation when planning for the state’s water future.

Asked why the state’s chief water planning agency does not take climate change projections into account, Mace said, “You’d have to talk to the Legislature to answer that question.”

State Sen. Troy Fraser, R-Horseshoe Bay, who is chairman of the Senate Natural Resources Committee, said the Legislature has no plans to direct the agency to incorporate climate change projections into its water planning in the future.

"It's not a parameter that we've requested they look at," he said, adding that "there is a disagreement within the people of Texas on the science of greenhouse gases."

Austin’s Diminishing Water Resources

When Perry held up a skateboard to mark the beginning of the “X Games” sports competition in Austin last month, his message was clear: Texas’ capital city is booming, like the rest of the state, thanks to Texas Republicans’ fiscally conservative and business-friendly policies. Between 2011 and 2016, Forbes projects, Austin’s economy will grow more than 6 percent. In the last decade, the city has added 155,000 people. 

An hour-and-a-half northwest of Austin, there is a different picture. Lake Buchanan, one of two water-supply reservoirs for much of Central Texas, is so low that lakeside residents regularly drive their Jeeps in what should be 20 to 30 feet of water. Cracked culverts and foundations of old houses that were flooded to make room for the reservoirs more than 70 years ago are now easily visible where the lake once stood. Low levels on the second reservoir, Lake Travis, have caused some Central Texas cities to spend millions of dollars extending their pipes further into the lake to take in needed municipal water supplies. Other towns have had to truck in water.

There’s little doubt in climate scientists’ mind that warmer temperatures have played at least some part in the extensive drought. 2011 was the hottest summer ever on record in Texas, and the following summer broke the record again. In a 16-month period, the lakes lost 130 billion gallons of water, or about one-fifth of their capacity. Officials called that rate “staggering” and suggested the hydrology of the lakes was significantly different than in the past. In the last three years, evaporation has claimed as much or more water from the lakes as the city of Austin uses annually. 

Even as some significant rainfall has taken place in recent months, the lakes have not recovered, due in part to higher temperatures that dried out the soil, water officials and scientists say. “The soil just sucked up any rain that came in and it didn’t run off [into the reservoirs],” said Karen Bondy, senior vice president of water resources for the Lower Colorado River Authority (LCRA), which manages the reservoir system.

To point out the impact of hotter temperatures on an already severe drought, LCRA officials have noted that even though up to seven inches of rain fell on some parts of the lakes’ watershed last September, the lakes gained only one percent of their capacity. By contrast, less than half the rain fell in similar areas in 2007, but added four times as much water to the lakes.

What’s happening to Austin’s water supply, and that of all the fast-growing cities outside of it, rings eerily true to a climate change study that the LCRA commissioned a decade ago. CH2M Hill, an engineering firm, conducted the study and evaluated a large body of climate research at the time. 

“The analysis that we were seeing was telling us [that] the one thing we are going to see is higher temperatures,” said James Kowis, who was the LCRA’s director of water planning at the time. That would mean drier soils, less runoff and more evaporation. In other words, population increases and more economic activity — “demand-side” water issues — were not the only ones that would affect Texas’ water supply in the future. 'Supply-side’ issues could have a large impact too, Kowis said.

The study also found that while there was no clear consensus on rainfall projections, Texas should expect to see more weather extremes and shifts in climate that are even more sudden than is already common in the state.

While the public has "assumed that human societies can adapt to gradual climate change,” the study’s authors wrote, "... recent climate research has uncovered a disturbing feature of Earth’s climate system: it is capable of sudden, violent shifts.”

A 2010 article in the Texas Water Journal by 12 scientists, including some at the University of Texas, Texas Tech University and Texas A&M University, had similarly dire predictions for the state’s water resources. “Under essentially all climate model projections, Texas is susceptible to significant climate change in the future … and has the strong potential of extreme stress on its water resources.”

Today, models also strongly indicate that the dividing line between Texas’ rainier eastern portion and its drier western portion, which is roughly at Interstate 35, will move farther to the east. That has major implications for the water supplies of all the booming cities along I-35 — namely Dallas, Austin and San Antonio.

Projected change in precipitation during Texas' spring season by the end of the century. Much of Texas relies on spring rainfall to ensure the state has enough water supplies throughout summers, where precipitation is typically minimal.
Projected change in precipitation during Texas' spring season by the end of the century. Much of Texas relies on spring rainfall to ensure the state has enough water supplies throughout summers, where precipitation is typically minimal.

But while Bondy said the LCRA is taking some climate projections into account while planning, the state is not, though Texas’ 2012 State Water Plan does note: “Climate scientists have developed models to project what the Earth’s climate may be like in the future under certain assumptions, including the composition of the atmosphere.” Attempts in 2009 by some lawmakers to establish a climate advisory committee for the Texas Water Development Board were unsuccessful.

The state’s 16 regional planning groups can make their own tweaks to anticipate fewer water supplies in the future, and some have done so. But Texas has not funded a single study on the impacts of climate change on water resources.

“We look at demographic projections, we look at financial projections,” to plan for water resources, said Mark Shafer, a University of Oklahoma-based climate scientist and the author of a portion of the federal government-sponsored National Climate Assessment. “Climate’s just another piece of that … climate should be just like any other information. We can pretend that this stuff doesn’t exist, and then be surprised when it does happen.”

Getting hit the hardest

Bruce McCarl, an agricultural economist whose work on climate change impacts won him the Nobel Peace Prize in 2007 (he shared the prize with Al Gore and other scientists), believes climate change will affect water resources far more than just a 15-percent reduction, as the state climatologist projects. McCarl has spent much of his life studying the impacts of global warming on agriculture. That’s where he says the effects will be the most severe in Texas. 

“There may need to be some sort of farmer assistance, at least with enhanced education, about how to cope,” McCarl said.

While some Texas cities are making their own plans for a hotter and drier climate, Texans who make their living in agriculture and reside in more remote areas of the state might not have time on their side. Scientists say smaller towns in West Texas and the Panhandle will be the hardest hit, as will rapidly growing and urbanizing South Texas.

South and West Texas are already more arid than much of the state. But they are also expected to see less rainfall on average than they have historically as temperatures continue to climb and warm air dominates the state, pushing the typical “meeting point” between cold and warm air — which causes precipitation — further to the north and east. That means it could get too hot and too dry to grow many commodity crops in Texas, and farmers would be forced to move northward.

The map on the right displays what Texas' water demand will be simply with population increase and economic shifts. The map on the right incorporates the effects of climate change that are expected if global greenhouse gas emissions continue to rise.
The map on the right displays what Texas' water demand will be simply with population increase and economic shifts. The map on the right incorporates the effects of climate change that are expected if global greenhouse gas emissions continue to rise.

Barry Goldsmith, a warming coordination meteorologist at the National Weather Service in Brownsville, said temperatures in the Rio Grande Valley could be up to 10 degrees higher in 50 years than they are today, potentially prompting a reversal of the explosive growth occurring in the region. 

“Everybody’s [going] to flee the southland because there’s not enough water for all the people that are here,” Goldsmith said.

South and West Texas rely heavily on underground aquifers for their water supplies, which means rain needs to be able to fall over a large area and seep into the ground to “recharge” those aquifers. A major portion of the Rio Grande River’s flow comes from groundwater-fed rivers, streams and springs in West Texas, for instance. Less rainfall puts that at risk.

“The expectation is that recharge is threatened by climate change,” said Ron Green, a hydrologist at the Southwest Research Institute, a private, independent research organization in San Antonio. “It’s those areas that rely on a good rain every few years to replenish their system that are going to suffer.”

While the state is not consulting scientists regularly on any of this data, another conservative, Republican-led neighbor is: Oklahoma. The state has used climate change modeling in its water plan for almost 10 years, said Shafer, the University of Oklahoma-based climate scientist. As a result, the state is considering measuring the potential yield of reservoirs in a “drought of record” using not just historical data, but also taking into account the effects of higher temperatures on evaporation rates and soil moisture.

The Texas Water Development Board says Texas' 16 regional water planning groups have the option to do the same — but fewer than half have done it.

Oklahoma’s approach, meanwhile, is the result of funding appropriated by that state’s legislature more than a decade ago, when the politics of climate change were very different.

“A lot has changed since then,” Shafer said, and today, “I don’t know if they would get a similar authorization through."

Disclosure: Texas A&M University and the Lower Colorado River Authority are corporate sponsors of The Texas Tribune. A complete list of Texas Tribune donors and sponsors can be viewed here.

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