Marathon Oil recognizes that water is a valuable resource that we share with the communities where we operate. Our use of water is guided by the core water stewardship practices of responsible sourcing, conservation, reuse and disposal.
Our water usage in U.S. onshore operations decreased by 34 percent from 2014 to 2015 because of reduced drilling and completion activities. In 2015, we used an estimated 40 million barrels of water, of which 3 percent was recycled and 72 percent was from nonfresh water (i.e., water that meets U.S. drinking water quality standards).
In the Eagle Ford, which accounts for approximately 85 percent of our water use, we preferentially use nonfresh water sources for drilling and completion activities. In 2015, we reduced nonfresh water use by 40 percent from 2014 to 2015. We also permanently installed recycle technology that we had been piloting since 2013, and recycled 1.1 million barrels of produced water for reuse in either stimulation or workover jobs.
This data excludes water usage from international operations where process water is primarily sourced from seawater. We leverage lessons learned across our U.S. resource plays, employ best practices, and participate in industry efforts to be good stewards of water resources and drive technological innovation in water management.
Marathon Oil engages externally to identify solutions for preserving scarce water resources in our U.S. onshore operations. We participated in a multi-operator effort with the Texas Water Development Board (TWDB) to voluntarily provide information obtained from company-owned brackish water wells in South Texas. The collaborative effort allowed the TWDB to fulfill the requirements of Texas legislation to identify brackish groundwater production zones for municipal, industrial and agricultural uses. The proprietary information the companies shared also enables the TWDB to more accurately map the brackish water zones of key aquifers, thereby providing a better picture of this potential future resource.
We also participated in a multi-operator project sponsored by the South Texas Energy & Economic Roundtable (STEER) to study four aquifers in the Evergreen Underground Conservation District. The goal of the study is to provide the district with additional scientific data to allow for tailored withdrawal schemes for individual aquifers to better use the resource and protect stressed systems.