Washington Department of Ecology - Air Quality ProgramThis map/layer displays geographic boundaries of areas that, at some point in the past, had failed to attain one of the National Ambient Air Quality Standards (NAAQS). EPA designates these areas as "nonattainment areas." Once the nonattainment area improves air quality and resolves the violation of the NAAQS, the area's status changes to "maintenance." In nontattainment areas, special air quality permitting requirements apply (eg. Nonattainment New Source Review.) Maintenance areas have additional planning and transportation conformity requirements for a minimum of 20 years after attaining the standard. Nonattainment and maintenance areas are eligible for additional funding to mitigate transportation emissions.ArcGIS FeatureLayerhttps://hub.arcgis.com/datasets/9f0e2e933c724af6b7f29c91760e5e5a_8engState of Washington Geospatial Open Data PortalPublicAir Quality Non-Attainment Areas [Washington (State)]Web servicesWashington (State)Last Modified: 2025-12-29