Surcharges

High strength surcharge billing is the method used by the City to ensure that dischargers of high strength wastewater pay their fair share of wastewater treatment costs.

Section 925.10 of the Sewer Use Code provides the basis for sewer rates and billing including high strength surcharge billing of both suspended solids (SS) and chemical oxygen demand (COD) levels in excess of “normal” domestic waste levels. The Sewer Use Code defines normal wastewater as having a suspended solids level of 250 milligrams per liter or less and a chemical oxygen demand level of 500 milligrams per liter or less. Any sewer user discharging wastewater with SS and COD concentrations above these levels may be subject to wastewater sampling, testing, and surcharge billing.

Sewer users subject to surcharge billing are sampled and the samples are analyzed to determine wastewater strength and characteristics. The wastewater samples are subject to laboratory analysis for both suspended solids and chemical oxygen demand concentrations. Those found to have concentrations in excess of normal levels are subject to surcharge billing. The basis for determining the extra strength costs are contained the City’s Sewer Use Code. Section 925.10(g) covers Suspended Solids while Section 925.10(h) deals with Chemical Oxygen Demand. Please call the Defiance Water Pollution Control Division at (419) 782-0841 with any questions regarding industrial pretreatment or surcharge billing.