Chapter 13.40
PUBLIC SEWERS – USE REGULATIONS

Sections:

13.40.010    Sanitary sewers – Prohibited discharges.

13.40.020    Combined and storm sewers – Natural outlets.

13.40.030    Public sewers – Prohibited waters or wastes.

13.40.040    Decision of public works director.

13.40.050    Discharge of prohibited substances – Subsequent procedures.

13.40.060    Interceptors required when.

13.40.070    Preliminary treatment or flow-equalizing facilities.

13.40.080    Industrial wastes – Control manholes.

13.40.090    Characteristics of water and wastes – Samples.

13.40.100    Industrial wastes – Special agreements.

13.40.010 Sanitary sewers – Prohibited discharges.

No person shall discharge or cause to be discharged any storm water, surface water, groundwater, roof runoff, subsurface drainage, uncontaminated cooling water, or unpolluted industrial process waters to any sanitary sewer. (Ord. B-102 Art. 5 § 1, 1978).

13.40.020 Combined and storm sewers – Natural outlets.

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 public works director. Industrial cooling water or unpolluted process waters may be discharged on approval of the public works director to a storm sewer, combined sewer, or natural outlet. (Ord. B-102 Art. 5 § 2, 1978).

13.40.030 Public sewers – Prohibited waters or wastes.*

No person shall discharge or cause to be discharged any of the following described waters or wastes to any public sewers:

A. Any gasoline, benzene, naphtha, fuel oil, or other flammable or explosive liquid, solid, or gas;

B. 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 two mg/l as CN in the wastes as discharged to the public sewer;

C. 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;

D. Solid or viscous substances in quantities of such 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, feathers, tar, plastics, wood, unground garbage, whole blood, paunch manure, hair and flashings, entrails and paper dishes, cups, milk containers, etc., either whole or ground by garbage grinders. (Ord. B-102 Art. 5 § 3, 1978).

*Prior ordinance history: Ord. 197 § 18, 1912.

13.40.040 Decision of public works director.

No person shall discharge or cause to be discharged the following described substances, materials, waters, or wastes if it appears likely in the opinion of the public works director that such 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 opinion as to the acceptability of these wastes, the public works director will give consideration to such factors as to 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 treatablilty of wastes in the sewage treatment plant, and other pertinent factors. The substances prohibited are:

A. Any liquid or vapor having a temperature higher than 150 degrees Fahrenheit;

B. Any water or waste containing fats, 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 degrees Fahrenheit;

C. Any garbage that has not been properly shredded. The installation and operation of any garbage grinder equipped with a motor of three-fourths horsepower or greater shall be subject to the review and approval of the public works director;

D. Any waters or wastes containing strong acid iron pickling wastes, or concentrated plating solutions whether neutralized or not;

E. Any waters or wastes containing iron, chromium, copper, zinc, and similar objectionable or toxic substances; or wastes exerting an excessive chlorine requirement, to such degree that any such material received in the composite sewage at the sewage treatment works exceeds the limits established by the public works director for such materials;

F. Any waters or wastes containing phenols or other taste-producing or odor-producing substances, in such concentrations exceeding limits which may be established by the public works director as necessary, after treatment of the composite sewage, to meet the requirements of the state, federal, or other public agencies of jurisdiction for such discharge to the receiving waters;

G. Any radioactive wastes or isotopes of such half life or concentration as may exceed limits established by the public works director in compliance with applicable state or federal regulations;

H. Any waters or wastes having a pH in excess of 9.5;

I. Materials which exert or cause:

1. 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),

2. Excessive discoloration (such as, but not limited to, dye wastes and vegetable tanning solutions),

3. Unusual BOD, chemical oxygen demand, or chlorine requirements in such quantities as to constitute a significant load on the sewage treatment works,

4. Unusual volume of flow or concentration of wastes constituting “slugs” as defined in TMC 13.22.010;

J. 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 such degree that the sewage treatment plant effluent cannot meet the requirements of other agencies having jurisdiction over discharge to the receiving waters. (Ord. B-102 Art. 5 § 4, 1978).

13.40.050 Discharge of prohibited substances – Subsequent procedures.

A. If any waters or wastes are discharged, or are proposed to be discharged to the public sewers, which waters contain the substances or possess the characteristics enumerated in TMC 13.40.040, and which in the judgment of the public works director may have a deleterious effect upon the sewage works, processes, equipment, or receiving waters, or which otherwise create a hazard to life or constitute a public nuisance, the public works director may:

1. Reject the wastes;

2. Require pretreatment to an acceptable condition for discharge to the public sewers;

3. Require control over the quantities and rates of discharge; and/or

4. Require payment to cover the added cost of handling and treating the wastes not covered by existing taxes or sewer charges under the provisions of TMC 13.40.100.

B. If the public works director permits the pretreatment or equalization of waste flows, the design and installation of the plants and equipment shall be subject to the review and approval of the public works director, and subject to the requirements of all applicable codes. (Ord. B-102 Art. 5 § 5, 1978).

13.40.060 Interceptors required when.

Grease, oil, and sand interceptors shall be provided when, in the opinion of the public works director, they are necessary for the proper handling of liquid wastes containing grease in excessive amounts, or any flammable wastes, sand, or 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 public works director, and shall be located as to be readily and easily accessible for cleaning and inspection. (Ord. B-102 Art. 5 § 6, 1978).

13.40.070 Preliminary treatment or flow-equalizing facilities.

Where preliminary treatment or flow-equalizing facilities are provided for any waters or wastes, they shall be maintained continuously in satisfactory and effective operation by the owner at his expense. (Ord. B-102 Art. 5 § 7, 1978).

13.40.080 Industrial wastes – Control manholes.

When required by the public works director, the owner of any property serviced by a building sewer carrying industrial wastes shall install a suitable control manhole together with such necessary meters and other appurtenances 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 public works director. The manhole shall be maintained by the owner at his expense, and shall be maintained by him so as to be safe and accessible at all times. (Ord. B-102 Art. 5 § 8, 1978).

13.40.090 Characteristics of water and wastes – Samples.

All measurements, tests, and analyses of the characteristics of waters and wastes to which reference is made in the ordinance codified in this chapter shall be determined in accordance with the latest edition of “Standard Methods for the Examination of Water and Wastewater,” published by the American Public Health Association, and shall be determined at the control manhole provided, 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. Sampling shall be carried out by customarily accepted methods to reflect the effect of constituents upon the sewage works and to determine the existence of hazards to life, limb, and property. (The particular analyses involved will determine whether a 24-hour composite of all outfalls of a premises is appropriate or whether a grab sample or samples should be taken. Normally, but not always, BOD and suspended solids analyses are obtained from 24-hour composites of all outfalls whereas pHs are determined from periodic grab samples.) (Ord. B-102 Art. 5 § 9, 1978).

13.40.100 Industrial wastes – Special agreements.

No statement contained in this chapter 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. (Ord. B-102 Art. 5 § 10, 1978).