The Study Assessed Long-Term Trends in Air Quality in Oil and Gas Producing Regions in Texas and Colorado
July 13, 2026
HEI Energy has published a new report, Air Quality Trends in Texas and Colorado Associated with Unconventional Oil and Gas Development. This study, led by Gunnar Schade, Texas A&M University, and Detlev Helmig, Boulder AIR, assessed long-term trends in air quality in oil and gas producing regions in Texas (1997–2023) and Colorado (2008–2024).
The investigators found contrasting trends between states. Outdoor air concentrations of non-methane hydrocarbons and nitrogen oxides in Texas rose and then plateaued alongside oil and gas production volumes, whereas Colorado saw declining outdoor air concentrations despite continued increased production.
Key Takeaways:
- The investigators compiled publicly available data on methane, nonmethane hydrocarbons, and nitrogen oxides (NOx) concentrations from air quality monitoring stations in each state. They then evaluated long-term air quality trends associated with UOGD in both states using statistical techniques for analyzing time-series data.
- Long-term trends in nonmethane hydrocarbon and NOx concentrations increased and then stabilized over time in Texas, generally correlating with regional UOGD production volumes in the state. In contrast, long-term trends in nonmethane hydrocarbon and NOx concentrations declined over time in Colorado, and methane growth was slower than the global background, while UOGD production continued to increase.
- These findings suggest that emissions levels near UOGD sites are likely declining in Colorado but not noticeably in Texas, demonstrating that potential differences in long-term trends in air pollutant concentrations at different locations might be attributable to regulations, UOGD operational changes, and local meteorological factors.
