(A) Liability for surcharge. Each industrial or non-industrial user who discharges wastes into the sewerage system shall be subject to a surcharge, in addition to the regular sewer charges, based on both the biochemical oxygen demand (or on the chemical oxygen demand where BOD cannot be determined) and the suspended solids content of the wastes, if these wastes have a concentration greater than the following:
(1) A biochemical oxygen demand of 300 milligrams per liter; or where BOD cannot be determined, then, in lieu of BOD, a chemical oxygen demand of 600 milligrams per liter; or
(2) A suspended solids content of 350 milligrams per liter.
(B) Computation of surcharge.
(1) The surcharge shall be determined as follows.
(2) The excess pounds of BOD (or COD) and the suspended solids will each be computed by first multiplying the customer’s billing sewage volume measured in units of 1,000 gallons for the current billing period by the factor 0.00834 and then multiplying this product by the difference between:
(a) The concentrations measured in milligrams per liter of the BOD (or COD) and of the suspended solids respectively in the customer’s sewage; and
(b) The allowed concentrations set out in division (A) above. The surcharge for each constituent will then be determined by multiplying the excess pounds of each constituent by the appropriate rate of surcharge set out in division (C) below.
(C) Rates of surcharge. The rate of surcharge for each of the aforementioned constituents shall be as follows:
(1) For biochemical oxygen demand (BOD): $0.20/lb;
(2) For chemical oxygen demand (COD) where BOD cannot be determined: $0.20/lb; and
(3) For suspended solids: $0.14/lb.
(D) Revision of rates of surcharge. Prior to May 1 of each year, the Clerk-Treasurer shall submit to the Common Council a comparison of the calculated unit costs for removing BOD and suspended solids from the wastewater treatment plant effluent during the previous calendar year with the unit charges currently in effect in order that the Common Council may determine whether the current rates of surcharge are adequate or should be changed by the Council.
(2003 Code, § 13.12.040) (Ord. 80-1, passed 1-14-1980)