Publication Summary

These standards have been developed under the authorization and specific requirements delineated with RCW 90.46 (Reclaimed Water). The type of uses, treatment and legal definition within the standards were developed in association with the Reuse Advisory Committee established under RCW 90.46.

These standards have been developed under the authorization and specific requirements delineated with RCW 90.46 (Reclaimed Water). The type of uses, treatment and legal definition within the standards were developed in association with the Reuse Advisory Committee established under RCW 90.46.

Users of this document are advised that reclaimed water suitable for reuse requires significant treatment and disinfection that is generally over and above conventional waste treatment facilities. Disinfection practices for Class A , B, C, and D reclaimed water are measured in total coliform, rather than fecal coliform traditionally used to measure wastewater disinfection effectiveness. Sampling is to be performed daily and Class A and B require less than 2.2 total coliforms per 100 milliliters based on a 7 day average.

These standards require that reclaimed water must be reliably generated. Emergency storage or alternate permitted discharge locations must be provided for reclamation facilities for use during upset conditions.. The standards also require automated alarms, redundancy of treatment units and stringent operator training and certification to meet the reliability criteria.

The standards describe allowable beneficial uses, the required level of reclaimed water treatment appropriate for each beneficial use, and any specific statutory requirements from RCW 90.46. Some treatment and beneficial uses are regulated uniquely to reclaimed water projects. The key to these uses is that it specifies "Reclaimed Water" must be generated prior to the allowance for a specific beneficial use. All reclaimed water generation and use must be covered under a reclaimed water permit that is issued jointly between Ecology and Health.