Chapter 22 PUBLIC WORKS AND IMPROVEMENTS*


Section 22-210 Definitions.


    The following words and terms as used in this article shall be deemed to mean and be construed as follows, unless the context specifically indicates otherwise:

     Bi-Monthly - Once every other month.

    Bi-Weekly - Once every other week.

    BOD (biochemical oxygen demand). The quantity of oxygen utilized in the biochemical oxidation of organic matter under standard laboratory procedure in five (5) days at twenty (20) degrees Celsius, expressed in milligrams per liter (mg/l).

    Building drain. That part of the lowest horizontal piping of a drainage system which receives the discharge from soil, waste and other drainage pipes inside the walls of the building and conveys it to the building sewer, beginning three (3) feet outside the exterior face of the building wall.

    Building sewer. The extension from the building drain to the public sewer or other place of disposal.

     Bypass - Means the intentional diversion of wastes from any portion of a treatment facility.    

    C.A. Control authority, City of Columbia.

    Capital charge. That portion of the total charges for sewage service which are levied for local capital costs, local investment in plant facilities and other local costs excluding operation, maintenance and replacement costs.

    Categorical pretreatment standard. Any regulation containing pollutant discharge limits promulgated by EPA in accordance with 33 U.S.C. § 1317 which applies to a specific category of users and which appear in 40 CFR Chapter I, Subchapter N, Parts 405-471.

    City. The City of Columbia, Missouri.

    City council. The duly elected mayor and council of the City of Columbia, Missouri, or their duly authorized representatives.

    COD (chemical oxygen demand). A quantitative measure of the amount of oxygen required for the chemical oxidation of carbonaceous (organic) material in wastewater using inorganic dichromate or permanganate salts as oxidants in a two-hour test, expressed in milligrams per liter (mg/l).

    Combined sewer. A sewer receiving both surface runoff and wastewater.

    Composite sample. A sample that is collected over time, formed either by continuous sampling or by mixing discrete samples. The sample may be composited either as a time composite sample: composed of discrete sample aliquots collected in one container at constant time intervals providing representative samples irrespective of flow; or a flow proportional composite sample: collected either as a constant sample volume at time intervals proportional to stream flow, or collected by increasing the volume of each aliquot as the flow increases while maintaining a constant time interval between the aliquots.

    Contributor. Any person responsible for the production of domestic, commercial or industrial waste which is directly or indirectly discharged into the city sanitary sewer system.

     Cooling Water -

(1)    Uncontaminated:  Water used for cooling purposes only which has no direct contact with any raw material, intermediate, or final product and which does not contain a level of contaminants detectably higher than that of the intake water.

(2)    Contaminated:  Water used for cooling purposes only which may become contaminated either through the use of water treatment chemicals used for corrosion inhibitors or biocides, or by direct contact with process materials and/or wastewater.

    Daily Maximum - The maximum allowable discharge of pollutant during a calendar day. Where daily maximum limitations are expressed in units of mass, the daily discharge is the total mass discharged over the course of the day.  Where daily maximum limitations are expressed in terms of a concentration, the daily discharge is the arithmetic average measurement of the pollutant concentration derived from all measurements taken that day.

    Director. The Director of the Department of Public Works of the City of Columbia, Missouri, or that person's authorized representative.

    Domestic wastewater. Wastewater discharging from dwellings (including apartment houses and hotels), office buildings, factories or institutions, and free from storm water, surface water and industrial wastewater.

    Dwelling unit. One or more rooms arranged for the use of one or more individuals living together as a single housekeeping unit, with cooking, living, sanitary and sleeping facilities.

    Garbage. Solid wastes from the preparation, cooking and dispensing of food, and from the handling, storage and sale of produce.

    Grab sample. An individual sample collected in less than fifteen (15) minutes, without regard for flow or time.

    Industrial wastewater. The water-carried wastes or liquid wastes from industrial or commercial processes as distinguished from domestic wastewater.

     Instantaneous Maximum Concentration - The maximum concentration allowed in any single grab sample.

    Interference. The inhibition or disruption of the City of Columbia's wastewater system or operations or its processing, use or disposal of sludge, by a user's discharge which alone or in conjunction with other discharges, causes, or contributes to the inhibition or disruption and which: (a) causes a violation of any requirement of the City of Columbia's NPDES Permit (including an increase in the magnitude or duration of a violation); or (b) prevents the use or disposal of sludge by the City of Columbia in compliance with the following statutes and regulations: Section 503 of the Clean Water Act; the Solid Waste Disposal Act; including Title II commonly referred to as the Resource Conservation and Recovery Act (RCRA); any state regulations contained in any state sludge management plan prepared pursuant to Subtitle D of the Solid Waste Disposal Act; the Clean Air Act; the Toxic Substances Control Act; or any more stringent state or local regulations. A user contributes interference when the user:

    (1)    Discharges a pollutant concentration or a daily pollutant loading in excess of that allowed by City of Columbia Ordinance or permit or by federal, state or local law;

    (2)    Discharges wastewater which substantially differs in nature and constituents from the user's normal average discharge;

    (3)    Knows or has reason to know that its discharge, alone or in conjunction with discharges from other users, would result in interference; or

    (4)    Knows or has reason to know that the City of Columbia is, for any reason, violating its NPDES Permit and that the user's discharge either alone or in conjunction with discharges from other users, increases the magnitude or duration of the City of Columbia's violations.

    mg/l. Milligrams per liter.

    Monthly Average - The arithmetic mean of the values for effluent samples collected during a calendar month or specified 30-day period (as opposed to a rolling 30-day window).

    Natural outlet. Any outlet into a watercourse, pond, ditch, lake or other body of surface water or groundwater.

    New source.

    (1)    Any building, structure, facility, or installation from which there is (or may be) a discharge of pollutants, the construction of which commenced after the publication of proposed pretreatment standards pursuant to 33 U.S.C. § 1317 which will be applicable to such source if such standards are thereafter promulgated in accordance with that section, provided that:

        a.    The building, structure, facility, or installation is constructed at a site at which no other source is located; or

        b.    The building, structure, facility, or installation totally replaces the process or production equipment that causes the discharge of pollutants at an existing source; or

        c.    The production or wastewater generating processes of the building, structure, facility, or installation are substantially independent of an existing source at the same site. In determining whether these are substantially independent, factors such as the extent to which the new facility is integrated with the existing plant, and the extent to which the new facility is engaged in the same general type of activity as the existing source, should be considered.

    (2)    Construction on a site at which an existing source is located results in a modification rather than a new source if the construction does not create a new building, structure, facility, or installation meeting the criteria of Section (1)(b) or (c) above but otherwise alters, replaces, or adds to existing process or production equipment.

    (3)    Construction of a new source as defined under this section has commenced if the owner or operator has:

        a.    Begun, or caused to begin, as part of a continuous on-site construction program

            1.    Any placement, assembly, or installation of facilities or equipment; or

            2.    Significant site preparation work including clearing, excavation, or removal of existing buildings, structures, or facilities which is necessary for the placement, assembly, or installation of new source facilities or equipment; or

        b.    Entered into a binding contractual obligation for the purchase of facilities or equipment which are intended to be used in its operation within a reasonable time. Options to purchase or contracts which can be terminated or modified without substantial loss, and contracts for feasibility, engineering, and design studies do not constitute a contractual obligation under this section.

    Normal wastewater. Wastewater which contains not over two hundred forty (240) mg/l of total suspended solids and not over two hundred (200) mg/l of BOD, and which does not contain any of the materials or substances listed in sections 22-215 and 22-215.1 in excess of allowable amounts specified in those sections.

    NPDES Permit. A permit issued under the National Pollutant Discharge Elimination System pursuant to the Federal Water Pollution Control Act, also known as the Clean Water Act, as amended, 33 U.S.C. § 1251 et seq., for a discharge into waters of the state.

    Pass through. A discharge of a pollutant from the City of Columbia's POTW into waters of the State of Missouri when such discharge causes a violation of any requirement of the City's NPDES permit, or a violation of a state or federal water quality standard or increases the magnitude or duration of any violation and which is the result of a user's discharge of the pollutant either alone or in conjunction with other users' discharges of the pollutant in the City of Columbia's POTW. A user contributes to pass through when the user:

    (1)    Discharges a pollutant concentration of a daily pollutant loading in excess of that allowed by City of Columbia ordinance or permit or by federal, state or local law;

    (2)    Discharges wastewater which substantially differs in nature and constituents from the user's normal average discharge;

    (3)    Knows or has reason to know that its discharge, alone or in conjunction with discharges from other users, would result in pass through; or

    (4)    Knows or has reason to know that the City of Columbia is, for any reason, violating its final effluent limitations in its NPDES permit and that the user's discharge either alone or in conjunction with discharge from other users, increases the magnitude or duration of the City of Columbia's violations.

    Person. Any individual, firm, company, association, society, corporation or group.

    pH. The logarithm (base ten) of the reciprocal of the hydrogen ion concentration in grams per liter of solution.

    (POTW) Publicly Owned Treatment Works. A treatment works as defined by 33 U.S.C. § 1292 which is owned by the City of Columbia. This definition includes any devices or systems used in collection, storage, treatment, recycling, and reclamation of wastewater or industrial wastes of liquid nature and any conveyances which convey wastewater to a POTW treatment plant. POTW shall also include any sewers that convey wastewater to the POTW from users outside the city limits of the City of Columbia who are by contract or agreement with the City, users of the City of Columbia POTW, even though the sewers may not have been constructed by or may not be maintained by the City of Columbia.

    Properly shredded garbage. The wastes from the preparation, cooking and dispensing of food that have been shredded to such degree that particles will be carried freely under the flow conditions normally prevailing in public sewers, with no particle greater than one-half inch in any dimension.

    Public sewer. A sewer in which all owners of abutting properties have equal rights, and which is controlled by public authority.

    Roof drain. A conduit for conveying the storm water or rainwater from a roof.

    Sanitary sewer. A sewer which carries domestic, industrial or normal wastewater and to which storm waters, surface waters and groundwaters are not admitted.

    Sewer. A pipe or conduit for carrying domestic, industrial or normal wastewater and other waste liquids or storm water.

    Significant industrial user (SIU). Noncategorical industry with >25,000 GPD; >5% of dry weather hydraulic or organic capacity; categorical industry; any industrial user designated by C.A. to have a reasonable potential to adversely affect POTW's operation.

    Significant noncompliance (SNC). Industrial user violations which meet one of the following criteria:

    (1)    Violation of wastewater discharge limits.

        a.    Chronic violations. Sixty-six (66) percent or more of the measurements exceed the same daily maximum limit or the same average limit in a six (6) month period.

        b.    Technical Review Criteria (TRC) violations. Thirty-three (33) percent or more of the measurements exceed the same daily maximum limit or the same average by more than the TRC in a six (6) month period.

    There are two (2) groups of TRCs:




Group I for conventional pollutants  
(BOD, TSS, fats, oil, and grease)  
TRC = 1.4  
Group II for all other pollutants  
TRC = 1.2  


        c.    Any other violation(s) of an effluent limit (average or daily maximum) that the control authority believes has caused, alone or in combination with other discharges, interference (e.q., slug loads) or pass-through, or endangered the health of the POTW personnel or the public.

        d.    Any discharge of a pollutant that has caused imminent endangerment to human health/welfare or to the environment and has resulted in the POTW's exercise of its emergency authority to halt or prevent such a discharge.

    (2)    Violations of compliance schedule milestones, contained in a local control mechanism or enforcement order, for starting construction, completing construction, and attaining final compliance by ninety (90) days or more after the schedule date.

    (3)    Failure to provide reports for compliance schedules, self-monitoring data, or categorical standards (baseline monitoring reports, ninety-day compliance reports, and periodic reports) within thirty (30) days from the due date.

    (4)    Failure to accurately report noncompliance.

     (5)   Any other violation or group of violations which the City of Columbia determines will adversely affect the operation or implementation of the local pretreatment program.

    Slug discharge. Any discharge at a flow rate or concentration which could cause interference as defined herein.

    Standard industrial classification. A classification pursuant to the latest edition of the Standard Industrial Classification Manual issued by the Executive Office of the President, Office of Management and Budget.

    Storm sewer or storm drain. A sewer which carries storm and surface waters and drainage, but excludes wastewater and industrial wastes; it may, however, carry acceptable cooling water and unpolluted water.

    Storm water. That portion of the rainfall or other precipitation which runs off over the surface during a storm and for a period of time following a storm during which the flow exceeds the normal runoff.

    Surface water. That portion of a rainfall or other precipitation which runs off over the surface of the ground.

    TSS (total suspended solids). Solids that either float on the surface of, or are in suspension in water, wastewater or other liquids and which are removable by laboratory filtering, expressed in milligrams per liter (mg/l).

     Upset - Means an exceptional incident in which there is unintentional and temporary noncompliance with technology-based permit effluent limitations because of factors beyond the reasonable control of the permittee, excluding such factors as operational error, improperly designed or inadequate treatment facilities, or improper operation and maintenance or lack thereof.

    User. The owner or occupant of property or premises that is connected directly or indirectly or has available to the property or premises the facilities of the POTW of the City of Columbia.

    User charge. That portion of the total charges for POTW service which are levied in a proportional and adequate manner for the cost of operation, maintenance and replacement of the wastewater treatment system.

    Wastewater or sewage. A combination of the water-carried wastes from residences, business buildings, institutions and industrial establishments.

    Wastewater system. All facilities for collecting, transporting, pumping, treating and disposing of wastewater.

    Wastewater treatment plant. The structures, equipment and processes used for treating wastewater.

    Wastewater treatment works (or sewerage system). All facilities for collecting, transporting, pumping, treating and disposing of wastewater.

    Watercourse. A channel in which a flow of water occurs, either continuously or intermittently.

     Weekly Average - The arithmetic mean of the values for effluent samples collected over a period of seven consecutive days.

(Code 1964, § 14.645; Ord. No. 10059, § 2, 2-6-84; Ord. No. 10857, § 1, 1-6-86; Ord. No. 14914, § 1, 8-5-96; Ord. No. 15324, § 1, 9-2-97; Ord. No. 16734, § 1, 1-2-01; Ord. No. 20922, § 1, 3-21-11)


(Ord. 20922, Amended, 03/21/2011, Prior Text; Ord. 16734, Amended, 01/02/2001, Prior Text)