No water service or fire sprinkler system connection shall remain or be installed to any customer unless the water supply system is adequately protected against cross connection by backflow prevention devices commensurate with the degree of hazard that either does or potentially may exist. The installation or maintenance of a cross connection that may endanger the water supply system quality shall be unlawful and is prohibited. Any such cross connections now existing or hereafter installed shall be abated. The control or elimination of cross connections shall be in accordance with this chapter, the most current Pacific Northwest section - American water works association cross connection control manual for accepted procedures and practices, and the Idaho regulations for public drinking water systems, section 01-8601.04, dated July 1985, or subsequent revisions, together with any other publications pertaining to cross connection control approved by the director of the state department of environmental quality. (2003 Code § 9-03-03)