§ 10-2-6 USE OF THE PUBLIC SEWERS.
   (A)   No person shall discharge or cause to be discharged any storm water, ground water, roof runoff, subsurface drainage, cooling water or unpolluted industrial process waters to any sanitary sewer.
   (B)   Storm water and all other unpolluted drainage shall be discharged to such sewers as are specifically designated as combined sewers or storm sewers, or to a natural outlet approved by the City Engineer. Industrial cooling water or unpolluted process waters may be discharged, upon approval of the City Engineer, to a storm sewer, combined sewer or natural outlet.
   (C)   Except as hereinafter provided, no person shall discharge or cause to be discharged any of the following described waters or wastes to any public sewer:
      (1)   Any liquid or vapor having a temperature higher than 150°F;
      (2)   Any water or waste which may contain more than 100 parts per million (100 ppm) by weight, of fat, oil or grease;
      (3)   Any gasoline, benzene, naphtha, fuel oil or other flammable or explosive liquid, solid or gas;
      (4)   Any garbage that has not been properly shredded;
      (5)   Any ashes, cinders, sand, mud, straw, shavings, metal, glass, rags, feathers, tar, plastics, wood, paunch manure, or any other solid or viscous substance capable of causing obstruction to the flow in sewers or other interference with the proper operation of the sewage works;
      (6)   Any waters or wastes having a pH lower than 5.5 or higher than 9.0 or having any other corrosive property capable of causing damage or hazard to structures, equipment and personnel of the sewage works;
      (7)   Any waters or wastes containing a toxic or poisonous substance in sufficient quantity to injure or interfere with any sewage treatment process, constitute a hazard to humans or animals, or create any hazard in the receiving waters of the sewage treatment plant;
      (8)   Any waters or wastes containing suspended solids of such character and quantity that unusual attention or expense is required to handle such materials at the sewage treatment plant; and
      (9)   Any noxious or malodorous gas or substance capable of creating a public nuisance.
   (D)   (1)   Grease, oil and sand interceptors shall be provided when, in the opinion of the City Engineer, they are necessary for the proper handling of liquid wastes containing grease in excessive amounts, or any flammable wastes, sand and other harmful ingredients; except that such interceptors shall not be required for private living quarters or dwelling units. All interceptors shall be of a type and capacity approved by the City Engineer, and shall be located as to be readily and easily accessible for cleaning and inspection.
      (2)   Grease and oil interceptors shall be constructed of impervious materials capable of withstanding abrupt and extreme changes in temperature. They shall be of substantial construction, water-tight, and equipped with easily removable covers which when bolted in place shall be gas-tight and water-tight.
   (E)   Where installed, all grease, oil and sand interceptors shall be maintained by the owner at his or her expense in continuously efficient operation at all times.
   (F)   (1)   The admission into the public sewers of any waters or wastes having any of the following shall be subject to the review and approval of the City Engineer:
         (a)   A five-day biochemical oxygen demand greater than 300 parts per million (300 ppm) by weight;
         (b)   Containing more than 350 parts per million (350 ppm) by weight of suspended solids;
         (c)   Containing any quantity of substances having the characteristics described in division (C) above; or
         (d)   Having an average daily flow greater than 2% of the average daily sewage flow of the city.
      (2)   Where necessary in the opinion of the City Engineer, the owner shall provide, at his or her expense, such preliminary treatment as may be necessary to:
         (a)   Reduce the biochemical oxygen demand to 300 parts per million (300 ppm) and the suspended solids to 350 parts per million (350 ppm) by weight;
         (b)   Reduce objectionable characteristics or constituents to within the maximum limits provided for in division (C) above; or
         (c)   Control the quantities and rates of discharge of such waters or wastes.
      (3)   Plans, specifications and any other pertinent information relating to proposed preliminary treatment facilities shall be submitted for the approval of the City Engineer and of the Water Pollution Control Commission of the state, and no construction of such facilities shall be commenced until said approvals are obtained in writing.
   (G)   Where preliminary treatment facilities are provided for any waters or wastes, they shall be maintained continuously in satisfactory and effective operation, by the owner at his or her expense.
   (H)   When required by the City Engineer, the owner of any property served by a building sewer carrying industrial wastes shall install a suitable control manhole in the building sewer to facilitate observation, sampling and measurement of the wastes. Such manhole when required shall be accessibly and safely located, and shall be constructed in accordance with plans approved by the City Engineer. The manhole shall be installed by the owner at his or her expense, and shall be maintained by him or her so as to be safe and accessible at all times.
   (I)   All measurements, tests and analysis of the characteristics of waters and wastes to which reference is made in divisions (C) and (F) above shall be determined in accordance with Standard Methods for the Examination of Water and Sewage, and shall be determined at the control manhole provided for in division (H) above, or upon suitable samples taken at said control manhole. In the event that no special manhole has been required, the control manhole shall be considered to be the nearest downstream manhole in the public sewer to the point at which the building sewer is connected.
   (J)   No statement contained in this section shall be construed as preventing any special agreement or arrangement between the city and an industrial concern whereby an industrial waste of unusual strength or character may be accepted by the city for treatment, subject to payment therefor by the industrial concern.
(1974 Code, § 7-5-6) (Ord. 459, passed 11-9-1960)