(A) Classes.
(1) All users of the wastewater treatment works shall be identified as belonging to one of the following user classes:
(a) Residential;
(b) Commercial;
(c) Industrial;
(d) Institutional; or
(e) Governmental.
(2) The allocation of users to these classes for the purpose of assessing sewer service charges shall be the responsibility of the City Clerk-Treasurer. Allocation of all users to user classes shall be based on the substantive intent of the definitions contained in this chapter. Industrial users discharging segregated domestic-strength waste only can be classified as commercial users for the purpose of rate determination.
(B) User charges.
(1) Each user shall be assessed and pay user charges in proportion to the user’s proportionate contribution of wastewater flows and loadings to the treatment works, with a minimum rate for pollutant loadings being the rate established for domestic-strength waste.
(2) The charges assessed users discharging domestic-strength waste shall be established proportionately on the basis of billable wastewater volume. Billable wastewater volume shall generally be calculated as metered water usage.
(C) Capital recovery charges.
(1) Each user shall be assessed and pay capital recovery charges in proportion to the user’s proportionate contribution of wastewater flows and loadings to the treatment works, with a minimum rate for pollutant loadings being the rate established for domestic-strength waste.
(2) The charges assessed users discharging domestic-strength waste shall be established proportionately on the basis of billable wastewater volume. Billable wastewater volume shall generally be calculated as metered water usage.
(D) Billable wastewater volume and loadings.
(1) The billable wastewater volume shall be calculated from the volume of metered water usage. For all users discharging domestic-strength waste, billable wastewater volume shall be equal to the metered water usage, as measured throughout the year. The billable amounts of wastewater loadings shall be calculated from the volume of metered usage, where the billable quantities will be those attributable to domestic-strength waste.
(2) For users with unmetered water services or not connected to the city’s water system, the billable wastewater volume shall be calculated from the volume of metered water usage or, at the discretion of the city, from the measurement or estimate of effluent flow at the user’s point of discharge. Measurements shall be according to a regular program prescribed by the city.
(3) For all users discharging extra-strength waste, billable wastewater volume shall be calculated from the volume of metered water usage or, at the discretion of the city, from the measurement of effluent flow at the user’s point of discharge. Measurements shall be according to a regular program prescribed by the city. For all users discharging extra-strength waste, billable amounts of wastewater loadings shall 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 other provisions of this chapter.
(4) The city may, at its discretion, require any user to install a water meter, wastewater meter, or such additional water meters as may be necessary to determine wastewater volume. When so required, such meter shall be of a type approved by the city, equipped with a remote registering recorder, and located at an accessible site on the owner’s property.
(E) Determination of user charges.
(1) User charges shall consist of a volume charge for domestic-strength waste and, if necessary, a surcharge for extra-strength waste. Such charges shall be developed in accordance with the approved sewer service charge system and computed in accordance with the formula presented below.
(2) User charge is as follows: UC = MUC + (VUC x F) + SUC
Where:
UC = User charge
MUC = Minimum charge ($/billing period) for administration costs and one unit of domestic-strength wastewater (100 cubic feet).
VUC = Volume charge per 100 cubic feet for OM&R costs.
F = Billable wastewater volume in 100 cubic feet.
SUC = Surcharge for extra-strength waste.
(3) Surcharges for extra-strength waste, if applicable, shall be computed in accordance with the formula presented below.
SUC = 0.00624 x F x [(B x BOMR) + (T x TOMR) + (P x POMR)].
Where:
0.00624 = Conversion factor.
B = Concentration of BOD5 in excess of domestic-strength waste.
F = Billable wastewater volume in 100 cubic feet.
T = Concentration of TSS in excess of domestic-strength waste.
P = Concentration of phosphorus in excess of domestic-strength waste.
BOMR = Unit surcharge per pound of BOD5.
TOMR = Unit surcharge per pound of TSS.
POMR = Unit surcharge per pound of phosphorus.
SUC = Surcharge for extra-strength waste.
(F) Determination of capital recovery charges.
(1) Capital recovery charges shall consist of a volume charge for domestic-strength waste and, if necessary, a surcharge for extra-strength waste. Such charges shall be developed in accordance with the approved sewer service charge system and computed in accordance with the formula presented below.
CRC = MCR + (Vcr x F) + Scr
Where:
CRC = Capital recovery charge.
MCR = Minimum charge ($/billing period) for capital-related costs assigned to customer service and one unit of domestic-strength wastewater volume.
Vcr = Volume charge per 1,000 gallons for capital-related costs.
F = Billable wastewater volume in 1,000 gallons.
Scr = Surcharge for extra-strength waste.
(2) Surcharges for extra-strength waste, if applicable, shall be computed in accordance with the formula presented below.
Scr = 0.00624 x F x [(B x BCR) + (T x TCR) + (P x PCR)].
Where:
0.00624 = Conversion factor.
B = Concentration of BOD5 in excess of domestic-strength waste.
T = Concentration of TSS in excess of domestic-strength .
P = Concentration of phosphorus in excess of domestic-strength waste.
F = Billable wastewater volume in 1,000 gallons.
BCR = Unit surcharge per pound of BOD5.
TCR = Unit surcharge per pound of TSS.
PCR = Unit surcharge per pound of phosphorus.
Scr = Surcharge for extra-strength waste.
(G) Determination of sewer service charges. Sewer service charges shall be computed for each user in accordance with the formula presented below.
SSC = Uc + CRc
Where:
SSC = Sewer service charge.
Uc = User charge.
CRc = Capital recovery charge.
(H) Additional charges. The sewer service charges established in this chapter shall not prevent the assessment of additional charges to users who discharge extra-strength waste or wastes of unusual character, or contractual agreements with such users, as long as the following conditions are met:
(1) The user pays OM&R costs in proportion to the user’s proportionate contribution of wastewater flows and loadings to the treatment works and no user is charged at a rate less than that of domestic-strength waste; and
(2) The measurement of such wastes are conducted according to the latest edition of Standard Methods for the Examination of Water and Wastewater in a manner acceptable to the city, as provided for in this chapter.
(3) A study of unit costs of collection and treatment processes attributable to fixed service, flow, BOD5, TSS, and other significant loadings shall be developed for determining the proportionate allocation of costs to fixed service, flows, and loadings for users discharging extra-strength wastes or wastes of unusual character.
(Prior Code, § 3.19)