WATER USE IN THE GAS-PRODUCING BARNETT SHALE AREA AND OTHER ISSUES

The Barnett Shale play, located in North Texas and currently the most prolific onshore natural gas play in the country, has seen a quick growth in the past decade with the development of new “frac” (aka, fracture stimulation) technologies needed to create flow pathways to produce gas in the very low permeability shales. This technology uses a large amount of fresh water (millions of gallons in a day or two on average) to develop a single gas well. As of end of year 2008, ~10,000 wells producing gas from the Barnett Shale have been drilled with thousands more likely to be drilled in the next couple of decades as the play expands out of its core area. A typical vertical and horizontal well completion consumes approximately 1.2 and 3.0 to 3.5 millions gallons of fresh water, respectively. This has raised some concerns among local communities and other groundwater stakeholders, especially in the footprint of the Trinity Aquifer.

We present results of a study assessing groundwater current and future use by industry in the Barnett Shale area. Future water use is highly uncertain, being dependent above all on the price of gas. Other important factors include geologic risk factors in the Barnett, technological factors (horizontal vs. vertical wells, water recycling), operational factors (number of well completions that can be done in a year, proximity of a fresh water source), and regulatory factors. We then contrast the gas play-specific groundwater use to other groundwater usages in the same area.