Protection of public water systems

1. Cross-connection control. a. Cross connections are prohibited except when and where, as approved by the authority having jurisdiction, suitable protective devices are installed, tested, and maintained to ensure proper operation on a continuing basis. b. A system shall be designed, installed, and maintained in such a manner as to prevent nonpotable liquids, solids, or gases from being introduced into the water through cross connections or any other piping connections to the system. 2. Interconnections. a. Interconnection between two or more systems shall be permitted only with the written approval of the department. b. Interconnection between a nonpublic and public water system shall not be permitted unless specifically approved in writing by the department. 3. Return of used water prohibited. Water used for cooling, heating, or other purposes shall not be returned to the system. Such water may be discharged into an approved drainage system through an airgap or may be used for nonpotable purposes. 4. Products in contact with water. All products that may come into contact with water intended for use in a public water system must meet American national standards institute/national sanitation foundation international standards 60 and 61. Suppliers of water for public water systems may not willfully introduce or permit the introduction of a product into the public water system which has not first been determined to meet these standards. At the discretion of the department, suppliers of water for public water systems shall compile and maintain on file for inspection by the department a list of all products used by the system. Prior to using a product not on the list, suppliers of water for public water systems shall either determine that the product meets appropriate American national standards institute/national sanitation foundation international standards or notify the department of the type, name, and manufacturer of the product. A product will be considered as meeting these standards if so certified by an organization accredited by the American national standards institute to test and certify such products. 5. Used materials. Containers, piping, or materials which have been used for any purpose other than conveying potable water shall not be used. 6. Water storage structures. Finished water storage structures shall have a watertight cover which excludes the entrance of birds, animals, insects, and excessive dust. Public water systems shall not construct uncovered finished water storage facilities. 7. Turbidity control. Subpart H systems that provide conventional filtration treatment or direct filtration shall develop individual filter profiles, perform individual filter self-assessments, and arrange for the completion of comprehensive performance evaluations as set forth under title 40 Code of Federal Regulations subparts P and T. At the direction of the department, systems that are required to conduct a comprehensive performance evaluation shall arrange for the completion of a full composite correction program and implement followup recommendations that result from the composite correction program. Comprehensive performance evaluations and composite correction programs shall be conducted by a party other than the system which is approved by the department.