(A) In order that the rates and charges may be justly and equitably adjusted to the service rendered, the city shall impose in addition to the charge based on volume a surcharge based on the strength and character of the sewage and waste which it is required to treat and dispose of. The city shall have the right to measure and determine or cause to be measured and determined, the strength and content of all
sewage and waste discharged either directly or indirectly into the city's sanitary sewage system in such manner and by such methods as may be deemed practical in the light of the conditions and attending circumstances in order to determine the proper charge.
(B) Any and all commercial and industrial installations having an effluent discharge into the city's sewers with an average BOD exceeding 200 parts per million concentration and/or an average daily suspended solids exceeding 250 parts-per million concentration shall be deemed to be discharging sewage of such strength as to require a surcharge for the treatment and disposal thereof. The surcharges shall be as follows:
BOD in excess of 200 mg/l | $0.22 per pound |
SS in excess of 250 mg/l | $0.18 per pound |
Ammonia in excess of 40 mg/l | $1.01 per pound |
Compatible fats, oils and greases in excess of 100 mg/l | $0.25 per pound |
Phosphorous in excess of 1 mg/l | $0.90 per pound |
(C) The city is authorized to prohibit the dumping of waste into the city’s sewage system, which, in the city’s discretion are deemed harmful to the operation of the sewage treatment works of the city and is further authorized to require methods of pretreatment of the wastes to reduce the harmful characteristics of the waste prior to discharge thereof into the city’s system.
(D) The surcharges to be imposed by the city for the treatment of such waste shall be based upon the following formula:
Surcharge = (Bo (BOD5 - ba) + So (SS - Sa) + Ao (Amm - Aa) x (8.34 x V). For the purposes of this formula, the following definitions shall apply.
(1) Bo = Average unit cost of treatment, chargeable to BOD, dollars per pound.
(2) BOD5 + The concentration of BOD5 in the wastewater from a specific user, parts per million.
(3) Ba = Maximum concentration of BOD5 in parts per million which can be discharged into the city's collection system without a surcharge - 200 parts per million.
(4) So = Average unit cost of treatment (including sludge treatment) chargeable to suspended solids, dollars per pound.
(5) SS = The concentration of suspended solids in the wastewater from a specific user.
(6) Sa = Maximum concentration of suspended solids in parts per million which can be discharged into the city's collection system without a surcharge - 250 parts per million.
(7) Ao = Average unit cost of treatment chargeable to ammonia, dollars per pound.
(8) Amm = The concentration of ammonia in the wastewater from a specific user, parts per million.
(9) Aa = Maximum concentration of ammonia in parts per million which can be discharged into the city’s collection system without a surcharge - 40 parts per million.
(10) V = Volume in million gallons.
(E) Customers outside the city limits shall pay 125% of the calculated charges, unless governed by individual agreement between the customer and the Utility Service Board.
('75 Code, § 7.15) (Ord. CO-67-18, passed 11-28-67; Am. Ord. CO-80- 19, passed 11-24-80; Am. Ord. CO-83-6, passed 7-11-83; Am. Ord. 85- 13, passed 7-25-85; Am. Ord. CO-04-27, passed 11-8-04; Am. Ord. CO- 06-10, passed 3-13-06; Am. Ord. CO-07-08, passed 6-25-07; Am. Ord. 10-06, passed 6-14-10; Am. Ord. 14-02, passed 3-24-14; Am. Ord. 17-18, passed 12-5-17)