Regional Haze Program

In 1977, Congress added § 169 to the Clean Air Act (CAA), which set forth the following goal for restoring pristine conditions in national parks and wilderness areas:

Congress hereby declares as a national goal the prevention of any future, and the remedying of any existing, impairment of visibility in mandatory Class I Federal areas which impairment results from man-made air pollution.

In 1999, EPA promulgated the “Regional Haze Regulations: Final Rule” (also referred to as the Regional Haze Rule) to address the combined visibility effects of various pollution sources over a wide geographic region with the goal of achieving natural visibility conditions at designated Class I areas by 2064. This program requires all states, including those that do not have Class I areas to participate in planning, analysis, and emission control programs to comply with the Regional Haze Rule. States with Class I areas are required to conduct certain analyses to establish goals for each Class I area in the state to 1) improve visibility on the haziest days and 2) ensure no degradation occurs on the clearest days. These goals and long-term strategies to achieve these goals are to be included in state implementation plans (SIPs) covering each ten-year period leading up to 2064. Amendments to the Regional Haze Rule were finalized in 2005 and 2017.

Planning Period 1


Planning Period 2

The Proposed Regional Haze Planning Period II SIP has completed public review. The public period began on February 27, 2022, and ended March 29, 2022. Public Comments received are linked below.