Sec. 86-40Discharges into public sewers

(a) Unpolluted waters. No person shall discharge or cause to be discharged any stormwater, surface water, groundwater, roof runoff, subsurface drainage, cooling water, or unpolluted industrial process waters to any sanitary sewer.

(b) Use of storm sewers. Stormwater 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 superintendent. Industrial cooling water or unpolluted process waters may be discharged upon approval of the superintendent, or a storm sewer or natural outlet.

(c) Prohibited discharges. Except as provided in this section, 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 degrees Fahrenheit.

(2) Any water or waste which may contain more than 100 milligrams per liter of fat, oil, or greases.

(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. The fixed upper limits for the constituents listed as follows, in parts per million, shall be:

a. Cadmium

0.02

b. Chromium

1.0

c. Copper

1.0

d. Cyanide

0.2

e. Nickel

1.0

f. Silver

1.0

g. Lead

0.1

h. Zinc

3.0

i. Phenol

0.05

j. Arsenic

0.05

 

(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.

(9) Any noxious or malodorous gas or substance capable of creating a public nuisance.

(d) Grease, oil, and sand interceptors. Grease, oil, and sand interceptors shall be provided when, in the opinion of the superintendent, 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 superintendent and shall be located as to be readily and easily accessible for cleaning and inspection. 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, watertight and equipped with easily removable covers which when bolted in place shall be gastight and watertight. When 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.

(e) Discharges subject to review. The admission into the public sewers of any water or wastes having a five-day biochemical oxygen demand greater than 300 milligrams per liter, containing more than 350 milligrams per liter of suspended solids, containing any quantity of substance having the characteristics described in subsection (c) of this section, or having an average daily flow greater than two percent of the average daily sewage flow of the city, shall be subject to the review and approval of the superintendent.

(f) Preliminary treatment facilities. Where necessary in the opinion of the superintendent, the owner shall provide at his expense such preliminary treatment as may be necessary to reduce the biochemical oxygen demand to 300 milligrams per liter and the suspended solids to 350 milligrams per liter, reduce objectionable characteristics or constituents to within the maximum limits provided for in subsection (c) of this section, or control the quantities and rates of discharge of such water or wastes. Plans, specifications, and any other pertinent information relating to proposed preliminary treatment facilities shall be submitted for the approval of the superintendent, and no construction of such facilities shall be commenced until such approval is obtained in writing.

(g) Maintenance of treatment facilities. 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) Control manhole. When required by the superintendent, 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 observations, sampling and measurement of the wastes. Such manhole, when required, shall be accessible and safely located, and shall be constructed in accordance with plans approved by the superintendent. The manhole shall be installed by the owner at his expense, and the owner at his expense shall maintain the manhole so as to be safe and accessible at all times.

(i) Measurements, tests, and analyses; standards. All measurements, tests, and analysis of the characteristics of waters and wastes to which reference is made in subsections (c), (e), and (f) of this section shall be determined in accordance with the latest edition, at the time of analysis, of Standard Methods for the Examination of Water and Wastewater, as prepared, approved, and published jointly by the American Public health Association, the American Water Works Association and the Water Environment Federation, and shall be determined at the control manhole provided in subsection (h) of this section, or upon suitable samples taken at such control manhole. If 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) Special arrangements. No statement contained in this section shall be construed as preventing any special agreement or arrangement between the city and any 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.