(A) In order to apportion more accurately the costs of the wastewater facilities of the city among its users, the relative strength of wastewater discharged to the facilities must be considered. The base waste strength against which all users shall be compared shall be normal domestic sewage. All users shall be assigned a waste strength multiplier which, when multiplied by the adjusted actual flow, will produce the user’s billable flow. For nonindustrial users, the waste strength multiplier shall be based on the biochemical oxygen demand (B.O.D.) and suspended solids (SS) characteristics of the waste stream only. The waste strength multiplier of industrial users may be based on other considerations and waste constituents and shall be determined by the city on an individual basis.
(B) A user’s waste strength multiplier shall not be less than 1.0 and shall be determined by 1 of the following methods:
(1) Standard classification system. The city shall assign all nonindustrial users a waste strength multiplier in accordance with an officially adopted classification schedule.
(2) Sampling and testing method. Any user disagreeing with the city’s assignment of a waste strength factor from the standard classification system may request an individual determination of actual waste strength based on sampling and testing. The user requesting the individual determination shall pay all costs associated with sampling and testing of the wastewater strength, including but not limited to: access to waste piping, including installation of a manhole; acquisition of appropriate grab samples or composite samples; testing for constituent concentrations; staff, City Engineer, or other designated representative’s time; and all related expenses. The city shall establish appropriate policies and procedures in advance of sampling and testing. The waste strength multiplier to be assigned to a user based on sampling and testing shall be determined in accordance with the following relations:
Waste Strength Multiplier = B.O.D. Ratio + SS Ratio ≥ 1.0
2
2
Where:
B.O.D. Ratio = Concentration of B.O.D. in ma/I ≥ 1.0
200 mg/l
SS Ratio = Concentration of SS in mg/l ≥ 1.0
250 mg/l