LOOKING BACK TO WATER USE PROJECTIONS IN THE GAS-PRODUCING BARNETT SHALE OF NORTH TEXAS

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 mid-2009, >12,000 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 overlying Trinity Aquifer. We first present results of a study assessing groundwater current and future use by industry in the Barnett Shale area. We contrast the gas play-specific groundwater use to other groundwater usages in the same area. Future gas production and water use are highly uncertain, being dependent above all on the price of gas as demonstrated by the recent natural gas price slump. Other important factors include geologic risk factors in the Barnett Shale area, technological factors (horizontal vs. vertical wells, water recycling), operational factors (drilling rig counts, number of well completions that can be done in a year, proximity of a fresh water source), and regulatory factors. The study projected a maximum water use of 24,500 AF/yr in 2009 (17,000 AF/yr of groundwater) for the whole play. As we engage in a new round of projections of water use in gas shales and tight sands for the whole state, we compare, in a third part of the presentation, projected and actual numbers for water use in the Barnett Shale.