Stormwater other than that exempted under Section 13.16.240 and all other unpolluted drainage shall be discharged to such sewers as are specifically designated as storm sewers, or to a natural outlet approved by the public works director and other regulatory agencies. Unpolluted industrial cooling water or process waters may be discharged, on approval of the public works director, to a storm sewer or natural outlet. (Ord. 603 (part), 2004)