Over the course of their lifetimes, the two coal-fueled power plants in Colorado Springs, Martin Drake and Ray Nixon, have undergone a series of changes, finally culminating in the complete closure of Martin Drake in September 2022. Many of these changes were motivated by the desire to reduce air pollution in the city and its surroundings. This study explores the effects of changes at the two power plants on four different air pollutants. Data collected by the Environmental Protection Agency are split into ten periods characterized by changes at each plant, including plants being partially or entirely shut down, the addition of pollution control equipment, and fuel changes. The changes are found to have had profound effects on levels of sulfur dioxide, but negligible effects on other pollutants. Mean levels of sulfur dioxide have decreased by approximately 2.73 ppb since before the changes to the two plants began. There is substantial evidence to suggest that changes at the plants were the primary contributors to this effect. There is also some evidence to suggest that spikes in sulfur dioxide levels may be caused by plumes of pollution being carried by the wind from other counties and states. Changes in carbon monoxide have not been linked to any type of event, but the 95th percentile of yearly concentrations of carbon monoxide is decreasing significantly. Finally, El Paso County is approaching unlawfully high concentrations of ozone, although no statistically significant trends were found in ozone data. Altogether, the data suggest that local power plants are an important contributor to Colorado Springs air pollution, but they are not the only contributor. Furthermore, they are not necessarily linked with levels of ozone, which is the pollutant most likely to exceed the standards set by the Environmental Protection Agency in El Paso County.