Ensuring a Safe, Sustainable Future Water Supply

Water usage in Texas will exceed the available water supply by 2060

• Rapid population growth is projected

• A single source will not be adequate to supply demand

• Diverse combination of technologies must be developed and implemented

Future Water DemandsState of Texas

• 8.5 million acre-feet per year of new water supplies needed to meet 2060 demand

• One acre-foot is equivalent to approximately 326,000 gallons

• Strategic Water Management• Using existing sources wisely• Conservation

• Innovative Water Technologies• Desalination• Brackish Groundwater Desalination• Aquifer Storage and Recovery• Reuse• Rainwater Harvesting

Meeting Future Demand

Desalination

• Process of removing dissolved salts from saline water

• Infinite supply – 370 miles of Texas coastline– 67,000 - 112, 000 acre-feet / year capacity

• Challenges– Higher TDS concentration, higher energy costs– Produces toxic by-products that require disposal

• Benefits– Drought-proof source– Cost effective option due to optimization of existing

technology

Desalination Benefits & Challenges

Brackish Groundwater Desalination

• Important desalination water supply option• Brackish groundwater is abundant in Texas

– Estimated at 2.7 billion acre-feet

• Challenges– Lack of detailed information on water quality

parameters – Inadequate assessment tools

Brackish Resources Aquifer Characterization System (BRACS)

• Funding received in 2009 – Map and characterize brackish aquifers – Develop better tools to assess parameters– Groundwater flow models to determine aquifer

productivity– Develop pilot scale models of innovative desalination

technologies

Aquifer Storage and Recovery

• Appropriated surface water stored in wet years for subsequent retrieval during drought

• Injected into a geologic formation capable of underground storage

• 67 Class V aquifer storage wells in use Texas• Many more available

Source: Texas Water Development Board

Aquifer Storage and Recovery

Reuse

• Reclaimed Water • Domestic or municipal wastewater• Treated to a quality suitable for reuse

– Direct reuse– Indirect reuse

• Not the same as grey water

• Funding for initial infrastructure– $4 billion to meet 2060 demands– Mostly for treatment plants and pipelines

• Water rights / regulatory issues• Water quality• Balance between human and ecological needs

Reuse Challenges

Rainwater Harvesting

• Renewed interest in a forgotten practice• 1”of rain on a 2,000 sq foot roof yields 1,000 gal of

useable water• Average system collects about 32,000 gal per year• Suitable usages

– Landscape irrigation– Household usage– Drinking water (with minimum treatment)

Emerging Technologies

• Atmospheric water generation• Solar powered water farms• Solar powered desalination

Atmospheric Water Generation

• Freshwater is produced from the atmosphere

• Converts humidity to liquid water• Cools the air below its “dew point”• Site-specific designs• Brine or solid salt is not produced-no

desalination

Solar Powered Water Producing Farms

• Clean drinking water from air and sunlight• Eliminates the need for fossil fuel power sources• Low cost

Source: Airwaterwell - Water from Air.com

Solar Powered Desalination Unit

• Large scale production• Eliminates the need for adjacent power plant• Does not generate brine or solid salt

Source:desalwave.com

The time to plan for the future is now. Humankind cannot continue to

squander our most precious resource. There is no life without water.

There is No Substitute

Source: witicitafalls.gov

References

www.twdb.state.tx.us/

www.airwaterwell.com/

www.watair.com

www.desalwave.com/