§ 51.51  PROHIBITED DISCHARGES.
   (A)   No person shall discharge or cause to be discharged any stormwater, surface water, groundwater, roof runoff, subsurface drainage, uncontaminated cooling water or unpolluted industrial process waters to any sanitary sewer.  Stormwater and all other unpolluted drainage shall be discharged to the sewers as are specifically designated as combined sewers or storm sewers or to a natural outlet approved by the Director of Public Works.  Industrial cooling water or unpolluted process waters may be discharged, on approval of the Director of Public Works, to a storm sewer, combined sewer or natural outlet.
   (B)   No person shall discharge or cause to be discharged any of the following described waters or wastes to any public sewer:
      (1)   Any gasoline, benzene, naphtha, fuel oil or other flammable or explosive liquid, solid or gas.
      (2)   Any waters or wastes containing toxic or poisonous solids, liquids or gases in sufficient quantity, either singly or by interaction with other wastes, to injure or interfere with any sewage treatment process, constitute a hazard to humans or animals, create a public nuisance, or create any hazard in the receiving waters of the sewage treatment plant, including but not limited to cyanides in excess of 2 mg/l as CN in the wastes as discharged to the public sewer.
      (3)   Any waters or wastes having a pH lower than 5.5 or having any other corrosive property capable of causing damage or hazard to structures, equipment, and personnel of the sewage works.
      (4)   Solid or viscous substances in quantities or of the size capable of causing obstruction to the flow in sewers, or other interference with the proper operation of the sewage works such as, but not limited to, ashes, cinders, sand, mud, straw, shavings, metal, glass, rags, feather, tar, plastics, wood, unground garbage, whole blood, paunch manure, hair and fleshings, entrails, and paper dishes, cups, milk containers, and the like, either whole or ground by garbage grinders.
   (C)   No person shall discharge or cause to be discharged the following described substances, materials, water, or wastes if it appears likely in the opinion of the Director of Public Works that the wastes can harm either the sewers, sewage treatment process or equipment, have an adverse effect on the receiving stream, or can otherwise endanger life, limb, public property, or constitute a nuisance.  In forming his or her opinion as to the acceptability of these wastes, the Director of Public Works will give consideration to the factors as the quantities of subject wastes in relation to flows and velocities in the sewers, materials of construction of the sewers, nature of the sewage treatment process, capacity of the sewage treatment plant, degree of treatability of wastes in the sewage treatment plant and other pertinent factors.  The substances prohibited are:
      (1)   Any liquid or vapor having a temperature higher than 150°F (65°C);
      (2)   Any water or waste containing fats, wax, grease, or oils, whether emulsified or not, in excess of 100 mg/l or containing substances which may solidify or become viscous at temperatures between 32 and 150°F (0 and 65°C);
      (3)   Any garbage that has not been properly shredded.  The installation and operation of any garbage grinder equipped with a motor of three- fourths horsepower (0.76 hp metric) or greater shall be subject to the review and approval of the Director of Public Works;
      (4)   Any waters or wastes containing strong acid iron pickling wastes, or concentrated plating solutions, whether neutralized or not;
      (5)   Any waters or wastes containing in excess of the following concentrations and similar objectionable or toxic substances; or wastes exerting an excessive chlorine requirement, to the degree that any material received in the composite sewage at the treatment works exceeds the limits established by the Director of Public Works for the materials.
Waste or Chemical
Concentration mg/l
Waste or Chemical
Concentration mg/l
Arsenic
0.5
Barium
4.0
Boron
1.0
Cadmium
2.0
Chlorine Demand
30.0
Chromium (Hexavalent)
0.5
Chromium (Trivalent)
2.0
Copper
2.0
Cyanide
0.025
Fluorine
2.0
Iron
4.0
Lead
0.1
Manganese
2.0
Mercury
0.0005
Nickel
2.0
Oil and Grease, etc.
30.0
(carbon tetrachloride extraction)
Phenols
0.5
Silver
0.2
Zinc
2.0
Total suspended solids
30.0
Total dissolved solids
3,500.0
 
      (6)   Any waters or wastes containing phenols or other taste- or odor-producing substances, in concentrations exceeding limits which may be established by the Director of Public Works as necessary, after treatment of the composite sewage, to meet the requirements of the state, federal or other public agencies of jurisdiction for the discharge to the receiving waters.
      (7)   Any radioactive wastes or isotopes of the half-life or concentration as may exceed limits established by the Superintendent in compliance with applicable state or federal regulations.
      (8)   Any waters or wastes having a pH in excess of 9.5.
      (9)   Materials which exert or cause:
         (a)   Unusual concentrations of inert suspended solids (such as, but not limited to, Fuller’s earth, lime slurries, and lime residues) or of dissolved solids (such as, but not limited to, sodium chloride and sodium sulfate);
         (b)   Excessive discoloration (such as, but not limited to, dye wastes and vegetable tanning solutions);
         (c)   Unusual B.O.D., chemical oxygen demand, or chlorine requirements in the quantities as to constitute a significant load on the sewage treatment works.
         (d)   Unusual volume of flow or concentration of wastes constituting “slugs” as defined herein.
      (10)   Waters or wastes containing substances which are not amenable to treatment or reduction by the sewage treatment processes employed, or are amenable to treatment only to the degree that the sewage treatment plant effluent cannot meet the requirements of other agencies having jurisdiction over discharge to the receiving waters.
(1992 Code, § 51.51)  (Am. Ord. 121277, passed 12-12-1977; Am. Ord. 2005-MC13, passed 10-24-2005)  Penalty, see § 51.99