(A) Calculating billable flows and loadings.
(1) Calculation of billable flows. The billable amount of flow will be calculated from the volume of metered water usage, or at the discretion of the city, from the measurement of effluent flow at user’s point of discharge. Measurements shall be according to a regular program prescribed by the city.
(2) Calculation of billable loadings.
(a) The billable amounts of BOD and TSS will be calculated by the measurement of these wastes according to a program prescribed by the city in keeping with the latest edition of “Standard Methods for the Examination of Water and Wastewater” and in accordance with this chapter.
(b) To insure compliance with § 51.122, the following procedures shall be followed in determining average loadings per billing period for industrial users:
1. When a particular reading indicates concentrations greater than or equal to normal domestic strength, the actual reading shall be entered into the average for billing purposes.
2. When a particular reading indicates concentrations less than normal domestic strength, normal domestic strength shall be entered into the average for billing purposes.
(B) Determination of sewer service charge for greater than normal domestic strength users.
SSC = Br + DSC + [Un x Bwv] + [Ubod x k x Bwv(Cbod-Nbod)]
+ [Utss x k x Bwv(Ctss-Ntss)]
SSC = Sewer service charge
Br = Base rate
DSC = Debt service charge
Un = Unit cost for the treatment of normal domestic strength wastewater.
Bwv = Billable wastewater volume of the particular user, in CCF.
Ubod = Unit cost for treatment of BOD in $/lb.
k = .00624 (conversion factor)
Cbod = Users concentration of BOD, in mg/l.
Nbod = 250 mg/l [Concentration of BOD in normal domestic strength wastes]
Utss = Unit cost for treatment of TSS in $/lb.
Ctss = User concentration of TSS, in mg/l.
Ntss = 300 mg/l [Concentration of TSS in normal domestic strength wastes]
(Ord. 150, passed 7-26-90)