Section 144-202-8 - WATER SUPPLY AND WASTE WATER DISPOSALA. Pool Water Supply1. The pool water supply must be adequate, of a safe, sanitary quality, and from a public water system or private source approved by the Department. (C).2. All portions of the water distribution system serving the public pool or spa must be protected against backflow and back-siphonage. Water introduced into the public pool or spa, either directly or to the recirculation system, must be supplied through an air gap or by another method approved by the local plumbing inspector (LPI) or the Department. (C).B. Public Pool or Spa Water Disposal1. The operator must obtain permission from the Department of Environmental Protection (DEP) or other proper authority, before any pool water is disposed of in a public sewer system, on any surface or into any body of water. (C)C. Backwash Disposal1. The operator must obtain permission from the proper authority before any backwash is disposed of in a public sewer system. (C)2. No backwash may be disposed of on any surface or in any body of water. (C)3. Backwash may be discharged in an approved subsurface wastewater disposal system sized, designed and installed in conformance with the Maine Subsurface Waste Water Disposal Rules, 10-144 CMR 241. (C)4. Backwash water must enter the approved disposal system through an air gap that is at least 1.5 times the backwash pipe diameter, or other LPI or Department-approved method to prevent backflow.10- 144 C.M.R. ch. 202, § 8