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Anna Mason, 11, catches tiny fish at Sailmaster Waterfall on Hurst Creek in Lakeway, which relies on runoff from The Hills golf course to prevent stagnation. “It is nice to see water running again,” said Andra Dearing, Lakeway Parks and Recreation director, after recent rainfall.

By Meagan O’Toole-Pitts
mpitts@ltview.com

With memories of last summer and beads of sweat still lingering from this sweltering heat, many of us wonder what’s happening to the Texas climate and water sources and what can we do about it.
Planning for infrastructure that will secure water sources for 2060 is under way throughout Texas, and experts are exploring answers to a common question: Why are Texas cities running out of water?
The good news is that the amount of water on Earth is fixed, so the planet as a whole is not running out of water. The bad news: Water is constantly shifting, requiring regular planning and building to meet the needs of 7.06 billion people and counting.
The problem isn’t the quantity of water, but the quality and placement of it. There is H2O aplenty on a planet covered more than two-thirds by water. The trouble lies in the cost of getting water to people and industry and navigating policies to plan sufficiently.
In addition to the hurdles in planning and funding new water infrastructure, conserving water while also meeting the needs of the public is another challenge.

092012 earth-water-distributionA look at water
Only 0.3 percent of the water on the planet is fresh water from lakes and rivers.
Nationwide, we withdraw 328 billion gallons per day from groundwater and 82.6 billion gallons per day from surface water, according to the U.S. Geological Survey.
The amount of water on Earth is finite. There is the same amount of water on Earth now as there ever has been, so the problem of drought is regional. Some of the water that filled Central Texas lakes and reservoirs is now somewhere else.
The questions are where to get water and how to conserve water while also meeting societal needs.
Water not only enables life, but also enables energy, industry, transportation, agriculture, recreation and cleanliness, said Dr. Michael Webber, assistant professor of mechanical engineering at University of Texas and co-director of Clean Energy Incubator.
“Agriculture doesn’t withdraw the most [water], but consumes the most,” Webber said.
Per capita, water withdraws are higher for wealthier countries, but poor countries use more water for agriculture, he said.
A large volume of water is used in the production of meat products and electricity, which affluent societies consume and use more, Webber said.
We use more water than we think – 1,321 gallons of water is used to produce 500 sheets of paper, he said.
More water is typically used during dry years, said Joe Cooper, general manager of the Lost Pines Groundwater Conservation District in Bastrop County.
“The evaporation process is a lot greater and people just use more water for things when it’s really hot and really dry,” Cooper said. “Typically, the greatest water use for any supplier is July, August, September and sometimes October.”
In September 2011, 2.06 million gallons of water and water-based retardant were used in snuffing out the Bastrop Complex and Union Chapel fires that burned a combined 33,120 acres and destroyed nearly 1,685 homes and 66 commercial structures in the Central Texas city, according to the Bastrop Complex Wildfire Case Study.

Water stress is increasing
Globally, sea levels rose 1.8 mm between 1963 and 2003. Heating of the oceans, which caused water expansion, and melting of snowcaps and glaciers contributed to 1.1 mm of the rise, Webber said.
In the debate on climate change, Webber argues that a water-energy nexus is to blame.
“Energy releases greenhouse gases, which contribute to climate change which causes us to move water using energy,” he said.
When regional water supplies run low, we look to other sources that are at a greater distance, requiring energy to be used in its transportation and expenses for its infrastructure.
When planning, the effects of infrastructure on the ecosystem and society must be considered.
Large water infrastructure projects, such as U.S. dams in the Appalachia and the West, displace people, Webber said.
Interbasin transfers divert water from one river basin to another, giving water to communities and cities with dwindling water supplies. But they’re not always popular.
Both interbasin transfers and water marketing can be controversial topics in Texas.
“There are a lot of parts of Texas that don’t have water, and there are lots of parts that have some water, and there’s some parts of Texas that have a lot of water,” Cooper said. “But getting that water to all of Texas that needs it can be a problem if it creates a deficit in an area that has rapid growth.”

Seeing surface water
In Texas, more than a million people depend on the Highland Lakes for their water.
The Highland Lakes, which include lakes Travis and Buchanan, form a chain of reservoirs on the Colorado River northwest of Austin created by the Lower Colorado River Authority from 1935 to 1951.
Many governmental entities throughout Central Texas that are in close proximity to the Colorado River and Lake Travis get their water via agreements with Lower Colorado River Authority.
The Brushy Creek Utility District and city of Round Rock, however, draw water from Lake Georgetown.
The cities of Bastrop and Elgin get their water from their own wells, and Aqua Water serves parts of those communities.
Smithville has its own water wells. Almost all communities below Austin (down the Colorado to Columbus) have their own municipal wells. The LCRA generally does not serve municipalities below Austin.

Between 2000 and 2010, the population of the greater Austin area grew by 20 percent to 1.72 million people and is projected to grow by 500,000 people by 2040, according to Austin Water Utility. To meet the needs, the city is in the midst of planning a third operational water treatment plant to take water from Lake Travis, slated for completion in summer 2014, said Raj Bhattarai, division manager at Austin Water.
During phase one of the project, the plant will pull 50 million gallons per day from Lake Travis, and may pull up to 300 million gallons per day in the future, he said.
After the closing of a water treatment plant in 2008, Austin was left with only two water treatment plants: the Davis Water Treatment Plant, built in 1954, and the Ullrich Water Treatment Plant, built in 1969.
Water infrastructure is aging, Bhattarai said, and there is a need for planning and action now.
Treating brackish water, which is groundwater than has more salinity than fresh water, could be another way to secure water for Austin, but reverse osmosis, used to remove salt from the water, is a complex and expensive process, Bhattarai said.
“We have great minds working on that,” he said.
The first public water system desalination production in Texas was just 30 years ago, but since then 44 public water supply desalination plants have popped up, Bhattarai said.
The state’s largest desalination plant, completed in 2007, is in El Paso. The plant, which has a capacity of 27.5 million gallons per day, cost $87 million to build. While treating 5 million gallons per day, maintenance and operations costs for the plant total $2.1 million annually.

Exploring groundwater
How much water an underground reservoir or aquifer holds is a hydrologist’s best guess.
“It can be calculated,” Cooper said. “When we go out and gauge a well, we know how far down the water is from the surface of the land, and then if you know the elevation of the surface of the land you know how far above sea level that water level is.”
In 2010, scientists at Stanford University discovered a way to monitor aquifer levels using images captured by satellites, but the technology is not yet readily available.
For now, most groundwater conservation districts monitor wells to estimate the capacity of aquifers.
The Lost Pines Groundwater Conservation District, which serves residents of Lee and Bastrop counties, set a moratorium on any new permits for non-exempt wells, which are wells that are capable of pumping more than 25,000 gallons a day and not used for agriculture or horticulture.
Non-exempt wells that pump more than 25,000 gallons a day are usually municipal wells and water supply corporations, which can pump up to 1 million gallons a day to sell to residents, Cooper said.
“The big requests at this time are from water marketers, people who have leased water rights and that want to come in and drill wells and pump water to – we don’t know exactly where but possibly San Antonio – other areas outside the district; that’s all we know,” he said.
Requests from water marketers to the Lost Pines district total more than 100,000 acre-feet.
An acre-foot is roughly 305,000 gallons or equal to the amount of water used by three average Austin homes in a year.
“We currently pump 20,000 acre-feet a year,” Cooper said. “If we pump too much water too fast, and we still have the high rate of growth that we do have, it could cause us to run out of adequate or sufficient supply by 2035 [or] 2040.”
The district’s largest user is Aqua Water Supply Corp., which uses 10,000 acre-feet per year to serve parts of Lee and Travis counties and nearly all of Bastrop County, he said.
The approximately 90,000 people in the district’s two counties get their water from the Colorado River Alluvium, which the city of Bastrop once used exclusively, Cooper said.
“It’s a good source of water – it receives recharge from river floods and also from rainfall,” he said. “But they’ve kind of outgrown it.”
Residents and commercial businesses are now looking at Carrizo-Wilcox wells, Cooper said.
Bastrop is growing, with the population expected to double or triple by 2030, he said.
“Our concern isn’t making sure we have water now; our concern is making sure we have water in five, 30, 50 years from now,” Cooper said. “There’s a whole lot to consider when you start giving up a resource long-term or permanently to some other that’s already outgrown its resources.”
In addition to serving Lee and Bastrop counties, water is transported from the district’s water supplies to Travis, Fayette and Williamson counties, Cooper said.
The groundwater district set the moratorium shortly after the 2005 passing of Texas House Bill 1768, which required districts to research what its future desired conditions would be in 2060, Cooper said.
The population of Texas is projected to more than double by 2060, increasing from 23 million to about 46 million people, according to the Texas Water Development Board.
According to the Texas State Water Plan, $53 billion will be needed just for new supplies by 2060, not including repair or replacement of prior systems, Webber said.

BELOW: Don Rauschuber, general manager of West Travis County Public Utility Agency, examines beds of anthracite coal in Trident water filters that process raw water from Lake Travis as it comes into the agency’s water treatment plant.


Photo by Meagan O’Toole-Pitts

092012 water series No 2 - water treatment plant

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