Industrial wastewater surcharge

The Industrial Wastewater Surcharge Program recovers costs associated with treating high-strength wastewater from industrial users with discharge permits.

High-strength refers to industrial wastewater that has higher concentrations of conventional pollutants than do typical households. Industrial wastewater can cost more for the County to treat because it can require higher levels of oxygen, create more biosolids, or require additional chemicals for treatment. The Industrial Wastewater Surcharge is charged in addition to the Sanitary District Unit Charge.

Onondaga County's wastewater treatment plants are designed to treat conventional pollutants, and excess treatment capacity is available to do so. Therefore, the County levies the cost of this service on the industrial users rather than imposing limits or spreading the cost out on all users. To reduce or eliminate their surcharge bill, some industrial users have installed their own private wastewater treatment systems.

How is the surcharge calculated?

WEP and each affected industry collect wastewater samples that are used to calculate wastewater strength. For the purpose of the surcharge program, wastewater strength is calculated based upon the concentrations of each of the following parameters:

5-day biochemical oxygen demand (BOD₅)
Total suspended solids (TSS)
Total phosphorus (TP)
Total Kjeldahl nitrogen (TKN).

These values are put in the surcharge formula to calculate the fee.

How to estimate a surcharge bill

WEP has developed an Excel spreadsheet to help you to estimate the surcharge bill that your company could receive based on the values that you input and current County costs. Projected costs can be estimated by changing the values for your industry or adjusting County fees.

Click here to use the Excel spreadsheet to estimate your costs.

Surcharge formula

The formula involves subtracting a threshold value from the concentration of surcharge parameters discharged by your industry and multiplying those values by the fee. The threshold value represents domestic wastewater discharges. Therefore, wastewater that exceeds the threshold (domestic) value is considered high-strength wastewater and is subject to a surcharge to recover the extra costs of treatment.

If the industrial wastewater shows concentrations of conventional parameters below threshold values, it is assumed that the unit charge is sufficient to cover wastewater treatment costs, and there is no surcharge.

Example

A company's surcharge could be calculated as follows.

Given parameters
BOD₅ threshold = 300 mg/L
Industry BOD₅ = 500 mg/L
Industry flow = 1,000,000 gal/yr
BOD₅ cost = $0.2459/lb
Conversion factor = 0.000008345

Example BOD₅ surcharge
(500 - 300) x 1,000,000 x 0.00000834 x $0.2459 = $410.16

This process is repeated to calculate charges for TSS, TP, and TKN.

For more information, please contact Sandra Tuori-Bell, 315-435-2260.