(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.
(B) Stormwater 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 Manager. Industrial cooling water or unpolluted process waters may be discharged, on approval of the City Manager, to a storm sewer, combined sewer or natural outlet.
(C) No person shall discharge or cause to be discharged any of the following described waters or wastes to any public sewers:
(1) Gasoline, benzene, naphtha, fuel oil or other flammable or explosive liquid, solid or gas;
(2) 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;
(3) 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; and
(4) Solid or viscous substances in quantities or 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 fleshings, entrails and paper dishes, cups, milk containers and the like, either whole or ground by garbage grinders.
(D) 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 City Manager, after consultation with 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 or her opinion as to the acceptability of these wastes, the City Manager will give consideration to such factors as: quantities of subject wastes in relation to flows and velocities in the sewers; construction material capacity of the sewage treatment plant; degree of the sewers; nature of the sewage treatment process; treatability of wastes in the sewage treatment plant; and other pertinent factors. The substances prohibited are:
(1) Liquid or vapor having a temperature higher than 150°F (65°C);
(2) 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) 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 either the City Manager or Public Works Director;
(4) Waters or wastes containing strong acid iron pickling wastes, or concentrated plating solutions whether neutralized or not;
(5) 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 federal, state or local standards for such materials;
(6) Waters or wastes containing phenols, or other taste or odor-producing substances, in such concentrations which, after treatment of the composite sewage, exceed federal, state or local standards for discharge to the receiving waters;
(7) Radioactive wastes or isotopes of such half-life or concentration as may exceed limits established by the City Manager in compliance with state or federal regulations;
(8) 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, Fullers 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 BOD, chemical oxygen demand or chlorine requirements in such quantities as to constitute a significant load on the sewage treatment works; and
(d) Unusual volume of flow or concentration of wastes constituting “slugs” as defined in this subchapter.
(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 such degree that the sewage treatment plant effluent, cannot meet the requirements of other agencies having jurisdiction over discharge to the receiving waters.
(E) (1) If 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 division (D) above, and which in the judgment of the City Manager 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 City Manager may:
(a) Reject the wastes;
(b) Require pretreatment to an acceptable condition for discharge to the public sewers;
(c) Require control over the quantities and rates of discharge; and/or
(d) 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 division (L) below.
(2) If the City Manager 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 City Manager, and subject to the requirements of all applicable codes, ordinances and laws.
(F) Grease, oil and sand interceptors shall be installed in any type of business or establishment, excluding residential dwellings, where grease or other objectionable materials may be discharged into a public sewer. Such interceptors (i.e., trap or oil/water separator) shall be of a size and design approved by the City Engineer.
(1) Each grease interceptor shall be installed and connected so it is at all times easily accessible for inspection, maintenance and removal of intercepted grease. Buildings remodeled for use requiring interceptors shall also be subject to these regulations.
(2) All grease interceptors must be installed in accordance with the appropriate State Uniform Plumbing Code provisions, being OAR 918-750 et seq. Abandoned grease interceptors must be disconnected as required by the city.
(3) The interceptors shall be maintained in efficient operating condition by periodic removal of accumulated grease. The use of chemicals to dissolve grease must be approved by the city prior to use. No such accumulated grease, oil or other accumulated contaminants shall be introduced into any drainage piping or public or private sewer discharging to the agency system.
(4) In the event the city, during maintenance of public sewer lines, record situations of grease accumulating in lines sufficient to restrict the normal flow of waste, upstream users shall be inspected. If the City Public Works Director determines that an upstream user was responsible for the grease or oil discharge, the user will be required to cease discharge of the prohibited waste, install an interceptor, maintain the interceptor and may be charged for the cost of cleaning the line. When, due to accumulated grease or other material, an obstruction of the public sewer line occurs, is a violation of 40 C.F.R. § 403.5(b)(3) or (6) and violation of this division (F).
(G) When sewer inspections provide evidence that an existing business is discharging grease, oil, sand or other materials deleterious to the sewer system into the public sewers, they shall be notified by certified mail. The notice shall provide a date and time for compliance with installation of grease traps/interceptors. Within 30 calendar days, the business must respond in writing with either:
(1) A plan for mitigation of the discharge complete with all actions which will be taken to minimize such discharges with a request for an exemption to the requirement to install a trap/interceptor; or
(2) Notice to the city that an interceptor has been installed. If the measures are determined to be adequate by the City Public Works Director and City Engineer, the exemption shall be approved by the City Manager. If determined not to be sufficient, then a grease trap/interceptor shall be required. If the request for exemption is denied, this determination may be appealed by the business owner to the City Council, whose decision is final.
(H) If an exemption is granted, the city retains the right to inspect the premises at any time to ensure that the approved mitigation practices/program is being utilized. Such exemptions shall be permitted for not longer than 36 months but may be renewed for periods not exceeding 36 months. During the period of the permit, if an inspection of sewer mains occurs and the user is identified as still discharging unacceptable amounts of grease or other materials so as to significantly disrupt sewer flows or sewage treatment processes, the city may then revoke the permit providing 90 days’ notice and require installation of a grease trap/interceptor by the end of the 90-day period.
(I) 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 or her expense.
(J) When required by the City Manager, 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 wastes. Such manhole, when required, shall be accessibly and safely located and shall be constructed in accordance with plans approved by the City Manager and Public Works Director. 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.
(K) All measurements, tests and analyses of the characteristics of waters and wastes to which reference is made in this subchapter 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(s) should be taken. Normally, but not always, BOD and suspended solids analyses are obtained from 24-hour composites of all outfalls where pHs are determined by periodic grab samples.)
(L) 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.
(M) No person shall discharge or cause to be discharged into the public sewers, any waste from cesspools, septic tanks or residue from private sewer pump stations without a permit approved by the City Public Works Director.
(Ord. 1136, passed 2-19-1990; Ord. 1214, passed 1-17-2000) Penalty, see § 52.99