Water Resource Reporting and Water Footprint from Marcellus Shale Development in West Virginia and Pennsylvania
Report and summary by Meghan Betcher and Evan Hansen, Downstream Strategies; and Dustin Mulvaney, San Jose State University
The use of hydraulic fracturing for natural gas extraction has greatly increased in recent years in the Marcellus Shale. Since the beginning of this shale gas boom, water resources have been a key concern; however, many questions have yet to be answered with a comprehensive analysis. Some of these questions include:
- What are sources of water?
- How much water is used?
- What happens to this water following injection into wells?
With so many unanswered questions, we took on the task of using publically available data to perform a life cycle analysis of water used for hydraulic fracturing in West Virginia and Pennsylvania.
Summary of Findings
Some of our interesting findings are summarized below:
- In West Virginia, approximately 5 million gallons of fluid are injected per fractured well, and in Pennsylvania approximately 4.3 million gallons of fluid are injected per fractured well.
- Surface water taken directly from rivers and streams makes up over 80% of the water used in hydraulic fracturing in West Virginia, which is by far the largest source of water for operators. Because most water used in Marcellus operations is withdrawn from surface waters, withdrawals can result in dewatering and severe impacts on small streams and aquatic life.
- Most of the water pumped underground—92% in West Virginia and 94% in Pennsylvania—remains there, lost from the hydrologic cycle.
- Reused flowback fluid accounts for approximately 8% of water used in West Virginia wells.
- Approximately one-third of waste generated in Pennsylvania is reused at other wells.
- As Marcellus development has expanded, waste generation has increased. In Pennsylvania, operators reported a total of 613 million gallons of waste, which is approximately a 70% increase in waste generated between 2010 and 2011.
- Currently, the three-state region—West Virginia, Pennsylvania, and Ohio—is tightly connected in terms of waste disposal. Almost one-half of flowback fluid recovered in West Virginia is transported out of state. Between 2010 and 2012, 22% of recovered flowback fluid from West Virginia was sent to Pennsylvania, primarily to be reused in other Marcellus operations, and 21% was sent to Ohio, primarily for disposal via underground injection control (UIC) wells. From 2009 through 2011, approximately 5% of total Pennsylvania Marcellus waste was sent to UIC wells in Ohio.
- The blue water footprint for hydraulic fracturing represents the volume of water required to produce a given unit of energy—in this case one thousand cubic feet of gas. To produce one thousand cubic feet of gas, West Virginia wells require 1-3 million gallons of water and Pennsylvania wells required 3-4 million gallons of water.
Table 1. Reported water withdrawals for Marcellus wells in West Virginia (million gallons, % of total withdrawals, 2010-2012)
As expected, we found that the volumes of water used to fracture Marcellus Shale gas wells are substantial, and the quantities of waste generated are significant. While a considerable amount of flowback fluid is now being reused and recycled, the data suggest that it displaces only a small percentage of freshwater withdrawals. West Virginia and Pennsylvania are generally water-rich states, but these findings indicate that extensive hydraulic fracturing operations could have significant impacts on water resources in more arid areas of the country.
While West Virginia and Pennsylvania have recently taken steps to improve data collection and reporting related to gas development, critical gaps persist that prevent researchers, policymakers, and the public from attaining a detailed picture of trends. Given this, it can be assumed that much more water is being withdrawn and more waste is being generated than is reported to state regulatory agencies.
Data Gaps Identified
We encountered numerous data gaps and challenges during our analysis:
- All data are self-reported by well operators, and quality assurance and quality control measures by the regulatory agencies are not always thorough.
- In West Virginia, operators are only required to report flowback fluid waste volumes. In Pennsylvania, operators are required to report all waste fluid that returns to the surface. Therefore in Pennsylvania, flowback fluid comprises only 38% of the total waste which means that in West Virginia, approximately 62% of their waste is not reported, leaving its fate a mystery.
- The Pennsylvania waste disposal database indicates waste volumes that were reused, but it is not possible to determine exactly the origin of this reused fluid.
- In West Virginia, withdrawal volumes are reported by well site rather than by the individual well, which makes tracking water from withdrawal location, to well, to waste disposal site very difficult.
- Much of the data reported is not publically available in a format that allows researchers to search and compare results across the database. Many operators report injection volumes to FracFocus; however, searching in FracFocus is cumbersome – as it only allows a user to view records for one well at a time in PDF format. Completion reports, required by the Pennsylvania Department of Environmental Protection (PADEP), contain information on water withdrawals but are only available in hard copy at PADEP offices.
In short, the true scale of water impacts can still only be estimated. There needs to be considerable improvements in industry reporting, data collection and sharing, and regulatory enforcement to ensure the data are accurate. The challenge of appropriately handling a growing volume of waste to avoid environmental harm will continue to loom large unless such steps are taken.
This FracTracker article is part of the Water Use Series