On July 13, 2016, the Missouri Clean Water Commission approved the most recent revision to the Antidegradation Implementation Procedure (AIP). The AIP was approved by EPA on July 30, 2018. According to 40 CFR 131.12, this procedure is intended to satisfy a requirement for states to develop and adopt a statewide antidegradation policy and identify methods for implementing such policy.

With more than 10 years of experience, Missouri’s Antidegradation processes are well-developed. It has served Missouri well and provided reasonable wastewater treatment technology determinations that have helped maintain the quality of waters of the State. Since the earliest days of Antidegradation Implementation review, engineers identified a number of areas in which the AIP is unclear, situations that were not addressed, or elements that needed additional clarification. The goal of this revision is to address many of these elements and incorporate ideas that improve and streamline the process, while maintaining the fundamental goal of antidegradation, protecting and maintaining the quality of Missouri’s waters.

Antidegradation Implementation Procedure

Summary of Previous Comments and Staff Responses
Draft Revised Antidegradation Implementation Methods
Draft Antidegradation Considerations for Individual Pollutants

Upcoming Meetings

There are no new meetings currently scheduled. Please check back, because we anticipate new information soon!

Past Meetings



The Water Protection Program is hosting a final stakeholder meeting to discuss revisions to the Missouri Antidegradation Implementation Procedure (AIP).

Lewis and Clark State Office Building Gasconade Camp Conference Room 1101 Riverside Dr. Jefferson City


No additional information at this time.