The answer to water scarcity can be found right under our boots
As the population grows in Texas and demand for fresh water increases, the state is turning to brackish water — water with slight to moderate salt content — as a source. How can the state sustainably tap into this?
Texas has an estimated 3.2 billion acre-feet of total brackish groundwater, with TDS concentrations between 1,000 and 10,000 mg/l. Brackish aquifers underlie most of the vast state, and brackish water wells dot the land. While almost every region has brackish water, the areas with the most are West Texas, North Central Texas, Central Texas, South Texas, and the Gulf Coast. Every major aquifer contains brackish water, and it can be found in almost all minor aquifers.
An enormous brackish aquifer in South Central Texas contains 417 million acre-feet of brackish water. On the Gulf Coast, an aquifer holds the state’s largest reserve at 522 million acre-feet, while the smallest reserve of approximately 9 million acre-feet is in the Lavaca region. Ample brackish water is available in the four regional water planning areas that have the greatest need.
Brackish groundwater, which is less salty than seawater but still too salty to drink, can be used for applications such as aquaculture, hydraulic fracturing, or cooling water for power plants, or it can be treated to provide a source of drinking water.
Brackish Water Needs Treatment
Brackish water causes scaling and corrosion in water wells and pipes and cannot be used in some industrial applications. It can cause health problems because it may also contain other dangerous contaminants, but salt alone can cause dehydration, dry mouth, thirst, fatigue, electrolyte imbalances, cramps, high blood pressure, heart disease, stroke, and in the case of high saline content, death.
Brackish water can also wreak havoc on agricultural production. Groundwater with TDS above 3,000 mg/l is not suitable for irrigation without dilution, and the buildup of salt in the soil from brackish water can keep land from supporting cultivation at all. It is generally unsafe for most poultry and livestock watering.
While water management and the public may be aware that salt can be removed from water, desalination has developed a reputation for being too costly. That might not be true.
Making Unusable Texas Brackish Water Useful
Desalination may be considered too costly for areas that can develop other water resources, such as fresh surface or groundwater, or nontraditional sources like treated wastewater. But is desalination more costly than crippling drought, water shortages that bring industry to a halt, and dry taps that radically alter daily life?
Water managers have developed a preference for reverse osmosis (RO) desalination because of its cost efficiency. RO removes salt by forcing water under pressure through semipermeable membranes that reject salt. The cost of preferred RO desalination has been trending down for the past decade, and the cost of water from traditional sources is going up. On a graph of desalination cost and traditional water cost, the lines eventually will cross, if they have not already, making desalination viable.
Another consideration is that cost-benefit analyses of desalination often pertain to seawater, but brackish water reverse osmosis (BWRO) desalination is far more cost-efficient than seawater desalination.
Additionally, Seven Seas’ BRWO projects are a sustainable solution to water scarcity, as they tap into abundant saline aquifers, leaving precious freshwater sources undisturbed.
Considering the heightened efficiency of brackish desalination, the lower costs of RO, the higher cost of traditional water sources, the growing scarcity of water in Texas, and the vast brackish water reserves underlying the state, it is not surprising that interest in utilizing them has risen.
While brackish desalination may be cost-effective, the initial costs may be prohibitive when a community, business, or industry has low access to capital. But Texans can secure financing for BWRO desalination.
One Texas City Tapped Its Brackish Reserves With a P3
The city of Alice, Texas, was experiencing recurrent drought and water shortages and had to pipe in water from 20 miles away at a high cost. To achieve better drought resilience, water independence, and lower costs, the city began construction of a brackish water desalination plant, but the project stalled because of a funding shortfall.
When decision-makers in Alice investigated their options for completing the plant, they learned about Seven Seas Water Group’s Water-as-a-Service®. Under the BOOT agreement, Seven Seas would complete the plant, own, operate, and maintain it, and transfer it to the city after a 15-year contract term. The city needs only to pay a bill for water delivered.
The Alice plant was the first Texas BWRO desalination plant under a P3 agreement, and it is erasing ambivalence about private participation in municipal utility services. Not only does the agreement guarantee quality and lower prices long-term, but it also lowers the prices the city was already paying for water. Now Alice is water independent, with a drought-resilient supply of water, and is free from decades of loan servicing.
If you are in Texas, the answer to your region’s water problems might be right underfoot. Contact Seven Seas to follow Alice’s lead toward water security and independence.
Image Credit: kanonsky/123RF
Erik Arfalk is the Senior Vice President of Business Development at Seven Seas, specializing in innovative and sustainable water and wastewater solutions in the US and the Caribbean. Previously, he was the Chief Commercial Officer at Fluence Corporation, where he launched MABR. Erik has held leadership roles at Atlas Copco and GE in Europe and the US, starting his career in strategy consulting. He holds a Master's in Business Administration and Economics from Lund University, Sweden. Erik's passion for water solutions and his talent for building strategic partnerships have established him as a respected industry leader.