§ 21-49. Discharge restrictions to the sewer system.

(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 waters to any sanitary sewer.

(b) 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) 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 wastewater treatment process, constitute a hazard to humans or animals, create a public nuisance, or create any hazard in the receiving waters of the wastewater treatment plant.

(3) Any waters or waste 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 sewer system.

(4) 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 sewer system such as, but not limited to, ashes, cinders, sand, mud, straw, shavings, metal, glass, rags, cloth materials, feathers, tar, plastics, wood, unground garbage, whole blood, paunch manure, hair and fleshings, entrails, paper dishes, cups, milk containers, etc., either whole or ground by garbage grinders.

(c) The following described substances, materials, waters or wastes shall be limited in discharges to municipal systems to concentrations or quantities which will not harm either the sewers, wastewater treatment process or equipment, will not have an adverse effect on the receiving stream, or will not otherwise endanger lives, limb, public property, or constitute a nuisance. The director of utilities may set limitations lower than those established in the regulations below if in his opinion more severe limitations are necessary to meet the above objectives. In forming his opinion as to acceptability, the director of utilities will give consideration to such factors as the quantity of subject waste in relation to flows and velocities in the sewers, materials of construction of the sewers, the wastewater treatment process employed, capacity of the wastewater treatment plant, degree of treatability of the waste in the wastewater treatment plant, and other pertinent factors. The limitations or restrictions on materials or characteristics of waste or wastewater discharged to the sewer system shall not be violated without approval of the director of utilities and are as follows:

(1) Wastewater having a temperature higher than one hundred fifty (150) degrees Fahrenheit (six hundred fifty (650 Celsius) or which will cause the temperature at the influent to a treatment plant to exceed one hundred four (104) degrees Fahrenheit (four hundred (400) Celsius).

(2) Wastewater containing more than twenty-five (25) milligrams per liter of petroleum oil, nonbiodegradable cutting oils, or products of mineral oil origin.

(3) Wastewater containing more than one hundred (100) milligrams per liter of oils, fat or grease.

(4) Any garbage that has not been properly shredded. Garbage grinders may be connected to sanitary sewers from homes, hotels, institutions, restaurants, hospitals, catering establishments, or similar places where garbage originates from the preparation of food in the kitchen for the purpose of consumption on the premises or when served by caterers.

(5) Any waste water having an excess of (limits in parts per million or milligrams per liter): silver 0.10, barium 2.0, aluminum 0.2, iron 0.3, phenol 0.2, arsenic 0.05, boron 1.0, manganese 0.05, lead 0.015, mercury 0.002, nickel 0.1, zinc 1.0, copper 0.1, cadmium 0.005, chromium 0.1, selenium 0.05, chlorides 250, nitrate 10(as N), nitrite 1(as N), sodium 160, thallium 0.002, asbestos 7 MFL and any substance or combination thereof that reduces the BOD by ten (10) percent will be considered as a toxic material. In addition, the limits for the following are: antimony 0.0, beryllium 0.0, bismuth 0.0 cobalt 0.0, cyanide 0.0, molybdenum 0.0, rhenium 0.0, tellurium 0.0, uranyl ion 0.0, strontium 0.0, herbicides 0.0, fungicides 0.0, formaldehyde 0.0 and pesticides 0.0.

(6) Any waters or wastes containing odor-producing substances exceeding limits of 3 (threshold odor number) or exceeding limits which may be established by the director of utilities.

(7) Any radioactive wastes or isotopes of such half-life or concentration as may exceed limits established in compliance with the applicable state or federal regulations.

(8) Quantities of flow, concentration, or both which constitute a slug.

(9) Waters or wastes containing substances which are not amenable to treatment or reduction by the wastewater treatment process employed, or are amenable to treatment only to such degree that the wastewater plant effluent cannot meet the requirements of agencies having jurisdiction over discharge to receiving waters and Class I reliability.

(10) Any water or wastes which, by interaction with other water or wastes in the public sewer system, releases obnoxious gases, forms solids which interfere with the collection system, or creates a condition deleterious to structures and treatment processes.

(11) Wastewater containing constituents in concentrations which are in excess of the concentration set for normal wastewater (two hundred fifty (250) mg/l BOD and TSS, thirty (30) mg/l TKN, fifteen (15) mg/l phosphorous).

(12) Wastewater having a pH in excess of 8.5.

(Ord. No. 96-06, § 1, 5-21-96)