New Billing Calculator Coming January 2026!
How to Read
Your Bill
Understanding any bill can be tough – we get it – so to help you learn more about your Four Rivers Sanitation Authority bill and how to read it, we offer a brief explanation.
Four Rivers Sanitation Authority (FRSA) receives water usage information (flow) for metered customer accounts from various water departments throughout Winnebago county. Well accounts, which are not metered, use an average flow based on metered accounts that have similar property usage. For instance, a one-family well account’s flow is calculated from the average flow of metered one-family accounts.
FRSA routinely samples and analyzes waste water from residential, commercial, industrial and government facilities. This analysis determines the Waste Water Characteristics (WWCs) that will be used for bill calculations. The WWCs for residential accounts are determined by annual group sampling and analysis.
The items that make up the WWCs are: Biochemical Oxygen Demand (BOD), Total Suspended Solids (TSS), Ammonia (NH4) and Phosphorus (PHO).
FRSA customers’ bills are calculated by multiplying the flow of fresh water as reported by your provider, and the concentrations of each of the WWC items by the current FRSA billing rate.
In September 2025, we simplified the residential bill format and condensed the technical language that describes the WWC’s into one simplified rate called “Domestic.”
For an example of our billing format, select the appropriate link below:
Still have questions? We’re ready to help – if you’re a residential customer, give us a call at 815-387-7500 or email our Customer Service Department for any questions or concerns regarding your bill. If you’re a commercial or industrial customer, call 815-387-7640 or email our Industrial / Commercial Billing Department. You can also always contact us via our Contact Us page.