The Washington Association for Colon Hydrotherapy (WAACH) is the first and only 100% peer-based collective of colon hydrotherapy professionals and Colon Hydrotherapy business owners in the state of Washington.

It was formed to ensure and promote the legal, safe and effective use of colon hydrotherapy in the state of Washington through education, political and legal activity.

WAACH was founded by three individuals, Tim Zimmer, Kristi Zimmer and Rebecca Harder; colon hydrotherapists and owners of colon hydrotherapy businesses.