Starting Feb. 1, drilling operators in Texas will have to report many of the chemicals they use in hydraulic fracturing. Environmentalists and landowners are looking forward to learning what acids, hydroxides and other materials have gone into a given well.

But a less-publicized part of the regulation is what some water experts are most interested in: the mandatory disclosure of the amount of water needed to “frack” each well. Experts call this an invaluable tool as they evaluate how fracking affects water supplies in the drought-prone state.

Hydraulic fracturing involves shooting water, sand and additives deep into the earth to retrieve oil or gas. Under the new rule, Texans will be able to check a website,, to view the chemical and water disclosures.

“It’s a huge step forward from where we were,” Amy Hardberger, an Environmental Defense Fund lawyer, said of the water-reporting rule.

The Texas Tribune thanks its sponsors. Become one.

Most fracked wells use 1 million to 5 million gallons of water over three to five days, said Justin Furnace, the president of the Texas Independent Producers & Royalty Owners Association.

Analysis from a June study prepared for the Texas Water Development Board suggested that less than 1 percent of the water used statewide went into fracking. Oil and gas groups say such numbers show their usage lags well behind that of cities.

But the data is a few years old, and drilling has since increased in places like South Texas’ Eagle Ford Shale. The amount of water used for fracking is “expected to increase significantly through 2020,” according to the state water plan published this month.

Dan Hardin, the water board’s resource planning director, said fracking is not expected to exceed 2 percent of Texas water use.

But drilling can send the water numbers much higher in rural areas, Hardin said. For example, he projects that in 2020, more than 40 percent of water demand in La Salle County, in the Eagle Ford, will go toward “mining,” a technical term that in this case means almost entirely fracking. Until recently, no water went toward mining there.

Researchers say predicting future water usage for drilling is tough, citing economic and technological uncertainties. Meanwhile, they want more data.

The Texas Tribune thanks its sponsors. Become one.

Jean-Philippe Nicot, a research scientist with the Bureau of Economic Geology at the University of Texas at Austin and the main author of the water board’s June study, noted that many drillers already report water usage to the Texas Railroad Commission (the commission’s new rule will mark the first time water disclosure is required).

Nicot would like to see more information about whether the water comes from aquifers or reservoirs or has been recycled from fracking operations.

Texas also needs better information about what is in water that has been in the earth and comes up in a well in addition to oil or gas, said Mark Engle, a geologist with the U.S. Geological Survey’s Eastern Energy Resources Science Center. That water can contain materials like grease and radioactive elements.

“Texas ranks pretty much dead-last of any state I’ve worked with for keeping track of that sort of data,” Engle said.

Texas Tribune donors or members may be quoted or mentioned in our stories, or may be the subject of them. For a complete list of contributors, click here.