Chapter 14.08
INDUSTRIAL WASTE SEWER SERVICE CHARGES1
Sections:
14.08.010 Wastewater strength determination.
14.08.020 Wastewater volume determination.
14.08.030 Wastewater rate determination.
14.08.010 Wastewater strength determination.
A. Each person discharging industrial wastes into a public sanitary sewer may, at his option, or shall, when directed by the manager/plant superintendent, construct and maintain an approved control manhole together with such flow measurement, flow sampling and sample storage facilities for all waste entering the public sewer as may be required by the manager/plant superintendent. These facilities will be used to obtain flow and wastewater characteristics for use as a basis for an industrial wastewater service charge. These facilities will be installed and maintained at the discharger’s expense.
B. In lieu of directing the construction of measurement, sampling and sample storage facilities, the manager/plant superintendent may require each person discharging industrial wastes into a public sanitary sewer to procure and test at the discharger’s expense, and in a manner approved by the plant superintendent, sufficient composite samples on which to base and compute the person’s industrial waste sewer service charge. The plant superintendent may, at his option, procure and test the wastewater discharge to determine the wastewater strength for use as a basis for an industrial wastewater service charge.
C. At least three consecutive or separate twenty-four-hour composite waste samples shall be taken for the initial year. Additional composite waste samples shall be taken at least once during each subsequent eighteen-month period to determine changes in wastewater strengths. A “composite sample” is a series of samples mixed together so as to approximate the average strength of discharge to the sewer. The sampling period may include any twenty-four consecutive-hour period, not necessarily midnight-to-midnight. All measurement methods shall be approved by the plant superintendent.
D. The plant superintendent shall determine which industrial waste discharges require sampling to determine waste strengths and shall in accordance with this section, determine the wastewater strengths. (Ord. 1676(part), 1992; Ord. 1618 §16(part), 1989).
14.08.020 Wastewater volume determination.
The wastewater volume shall be determined on the basis of actual flow measurement. In the event that actual flow measurement is not provided, the industrial waste charge shall be computed using the metered water flow to the premises as a basis for water flow. Metered water flow shall include all water delivered to or used on the premises and which is discharged to regional facilities. Cooling waters or water not discharged to a sanitary sewer shall be separately metered at the user’s expense using deduct meters or any other manner approved by the plant superintendent prior to allowing deduction of such flow from the total water used on the premises in computing the industrial waste sewer service charge. All metered water flows shall be metered at the user’s expense. Allowances may be made in accordance with the requirements of this section. (Ord. 1676(part), 1992; Ord. 1618 §16(part), 1989).
14.08.030 Wastewater rate determination.
“Extra-strength industrial waste discharge” shall be defined as industrial, commercial or hospital industrial wastes discharged into the sewer system containing a total of more than sixty pounds of biochemical oxygen demand or suspended solids in any one day and having an average strength in excess of three hundred ppm of biochemical oxygen demand or suspended solids.
A. Composite Charge Rate.
1. For each extra-strength industrial waste discharger the composite charge rate shall normally be employed. The composite charge rate shall be based on the average of the composited samples obtained in accordance with the provisions of Section 14.08.010 and the wastewater volume as determined in accordance with Section 14.08.020.
2. The rate shall be established per three hundred ppm of biochemical oxygen demand, or suspended solids, or fraction thereof in excess of the first three hundred ppm of biochemical oxygen demand or suspended solids per one thousand gallons of water. The rate shall be for the higher concentration of either BOD or suspended solids, but not assessed for both.
B. Other Charge Rates. If unusual effluent conditions make the calculations by the composite method impossible or unrealistic, another method of sampling and computation may be implemented by the plant superintendent.
C. Allowances.
1. Appropriate allowances may be made at the discretion of the plant superintendent for the volume of domestic sewage at permissible limits of strength. The domestic sewage allowance shall be based on a ratio of one thousand gallons per month for each twenty-seven employees using the sanitary facilities.
2. Favorable consideration will be given to users that can discharge compatible wastes during low-flow periods of the night and on weekends. Case-by-case consideration will be given to those users at the discretion of the plant superintendent to make rate adjustments commensurate with decreased impact on the plant.
3. In the event wastewater volume determination is computed using metered water flow and deduct meters are not utilized, special allowances may be made at the discretion of the plant superintendent for water consumption or loss based on verifiable industry standards (e.g., evaporation, use in product, etc.).
D. Adjustments. The plant superintendent may check sewage strength as outlined in this section and give notice that extra strength charges be adjusted where applicable at any time in accordance with the most recent analysis.
E. Resampling Request--Fees. Any user may request the plant superintendent to resample wastewater at no charge if eighteen months or more have elapsed since the last such sampling. If less than eighteen months have elapsed since the last sampling, then requests for the plant superintendent to resample wastes shall be submitted in writing and accompanied by full payment for the resampling fee. The resampling fee for each day of sampling shall be established by the plant superintendent.
F. Implementation of Charges. Changes in extra strength charges shall be effective for the month next following the month in which notice of adjustment was given. (Ord. 1676(part), 1992; Ord. 1618 §16(part), 1989).
Prior ordinance history: Ord. 1502.