Arizona Department of Environmental Quality (ADEQ) approved, on December 28, 2016, for permitting the construction and use of two site-built designs piloted by Watershed Management Group through a two-year process with 22 participating sites. The Proprietary Treatment Product Listing for the two designs now expands the range of composting toilet options available to Arizonans. The two batch-style composting toilet system designs are 1) a 55-gallon barrel system and 2) a masonry chamber system. The document provided here includes sizing information, technical details, and operations and maintenance of both systems. Updated 10 January 2017.