Where will Texas' drinking water come from?

Idea person: Amanda Brock, C.E.O of Water Standard.

Big idea: We can make drinkable water from saltwater.

Where the idea came from: Brock grew up on a farm in Rhodesia/Zimbabwe. Her family grew cotton, sugar cane and wheat, and ran cattle and goats on the plains of the dry lowveld near traditional native tribesman. "You can't even begin to understand the suffering caused by droughts when I was growing up," she says.

Desalination: Brock attended the University of Natal in South Africa as a pre-law student, and after graduation moved to Baton Rouge to attend law school at Louisiana State University. After a stint at Vinson & Elkins and various energy companies, Brock started a company focused on desalinating and treating water for the oil and gas industry.

Desalination has been around for hundreds of years; sailors boiled seawater to make fresh water from evaporation. Yet it's only in the last few decades that large-scale desalination has become economically feasible. Brock is strongly in favor of conservation and reuse: better toilets and shower heads, updating our aging water infrastructure and taking every other available step. Still, she points out, "with even the best conservation and reuse efforts, we have a limited supply of water from our lakes and rivers, but we have an endless supply from the oceans."

That possibility drew Brock to the desalination business, and her energy background led her to offshore seawater treatment using desalination.

Brock thinks a lot about her adopted homeland. With Texas' population expected to double in 50 years, she worries how Houston and the state will manage to meet their long-term water needs. The drought of 2011 brought those worries home: Her ranch in the Brenham area lost over 200 trees, including oaks over 300 years old.

Brackish water is underneath our feet: Brackish water, though not potable, is typically less salty than ocean water. A 2003 study cited below found that there are approximately 2.7 billion acre feet of brackish groundwater in the state, with the Gulf Coast Aquifer having the largest supply. "But we don't know enough about the brackish water in these aquifers," Brock says. "They should be part of an overall water plan."

Next steps: Brock believes that to meet Houston's future needs, the city should carefully consider its brackish groundwater resources as well as seawater desalination: "We should at least know what our alternatives are and be able to develop a fast track project before it's too late."

Already El Paso has built the world's largest inland desalination plant in the middle of the Chihuahuan Desert. The Kay Bailey Hutchison Desalination Plant removes salt from brackish water. A joint project of El Paso Water Utilities and Ft. Bliss, it produces 27.5 million gallons of fresh water daily.

Urgency: "Without oil and gas we innovate," says Brock. "Without water we die."