§ 36-442. Surcharges.

Sewer use surcharges will be applied for discharges having a five-day BOD greater than 300 mg/l, for discharges containing more than 300 mg/l of suspended solids, for discharges containing more than 20 mg/l of ammonia nitrogen, and for discharges that exceed maximum permitted volume. Where, in the city manager's opinion, the BOD does not provide a meaningful measurement of wastewater strength, the city manager may substitute COD limits and apply surcharges for wastewater having a COD greater than 600 mg/l.

(1)

For the purposes of applying surcharges, it has been determined that the costs of operating the POTW can reasonably be subdivided into four components, as follows:

a.

Flow related components including collection system elements, pumping facilities and hydraulic capacity at the treatment facilities, which together make up 20 percent of overall operating costs.

b.

Oxygen demand components, including biological treatment process elements, which together make up 25 percent of overall operating costs.

c.

Solids handling components, including clarifiers, digesters, drying beds and sludge disposal facilities, which together make up 35 percent of overall operating costs.

d.

Ammonia nitrogen handling components including a portion of the biological treatment process elements, which together make up 20 percent of overall operating costs.

_____

(2)

In any case where wastewater flow volume exceeds permit limits, or where the wastewater strength exceeds the surcharge limits established by this article, surcharge factors will be computed and applied to the user charges that would otherwise be due. Surcharge factors will be calculated for any or all components exceeding the surcharge limits, and individual components added together to produce a total surcharge factor to be applied as follows:

a.

Where BOD is used with 24-hour composite samples:

b.

Where COD is used with 24-hour composite samples:

c.

Where BOD is used with a single grab sample:

d.

Where COD is used with a single grab sample:

(Code 1989, § 10-102; Ord. of 10-2-1995, § 14.2)

_____