​​Water Utility Financial Benchmarks

The Public Service Commission (PSC or Commission) calculates benchmark data for over 575 water utilities based on data from the PS​C Annual Reports​​. Benchmarks allow utilities to compare their statistics on expenses, revenues, and gallons pumped with statistics for all other utilities as well as utilities of similar size. 

Available Benchmark Data 

  • Statewide Benchmark: grouped by utility class and water source (surface water, groundwater, or purchased water).

  • Individual Water Utility Benchmarks: Compares statewide benchmarks with a selected utility’s reported amounts. The individual utility benchmarks appear in the far right-hand column of the report.​

The Commission groups water utilities into class AB, C or D categories based on the number of customers served. Class AB utilities have 4,000 or more customers, Class C utilities have between 1,000 and 4,000 customers, and Class D utilities have fewer than 1,000 customers.​ Additional items of note about benchmark reports:​​

    • Benchmark reports can be exported to Microsoft Excel.

    • ​Most utilities file their PSC Annual Reports in April and May. During this timeframe, the benchmark reports ​will fluctuate daily as new reports are added to the database.

    • ​​​​PSC Annual Reports contain utilities’ self-reported data, which may contain errors. While these errors do not likely have a material impact on benchmark averages, they can distort minimum and maximum values significantly.​

Benchmark Categories

  • ​Revenues – Two benchmarks use revenues in Account 461, Metered Sales to General Customers. These benchmarks include sales revenues per customer and sales revenues per thousand gallons of water sold.  This benchmark category also includes operating revenues per full-time equivalent employee.

  • Expenses – Because water supply sources and utility size can have significant impacts on utility operating and maintenance costs, the expense benchmarks segregate expense by utility class as well as water source.  Water supply sources include self-supplied groundwater or surface water, with Lake Winnebago utilities reported separately, or purchased water. Benchmarks for Account 408, Taxes, include separate reports for City and village owned water utilities and sanitary districts because sanitary districts do not pay the local and school property tax equivalent. This benchmark category includes expenses relative to average plant investment, total operating revenues, gallons of water sold, and number of customers. In order to eliminate potential duplication issues for utilities that bill public fire protection (PFP) service directly to customers, the number of customers excludes PFP customers. The expense benchmarks also include total operating expenses per full-time equivalent employee. 

  • Mass Property Plant Accounts – The benchmarks for mains, service lines, meters, and hydrants include the average cost for both plant additions and plant retirements. Plant value amounts are based on data in the Water Utility Plant in Service schedules for utility-financed and contributed plant.  Units added and retired are based on data in the related schedules. The number of hydrants includes flushing hydrants.
  • Pumping Statistics – Benchmarks include kilowatt hours of electricity used to operate pumps.
  • Financial Ratios – The benchmarks include the ratio of long-term debt compared to total capital structure at the end of the year. Total capital structure includes long term debt plus municipal earning equity. There is no benchmark for utilities with no long-term debt or with negative municipal equity. The other benchmark is rate of return on average net investment rate base.​​​ ​

Benchmark Depreciation Rates

Commission staff developed benchmark depreciation rates for municipal water utilities using a study of historical plant additions and retirements. A listing by account of depreciation rate ranges and a total utility composite rate range are contained in the Benchmark Depreciation Spreadsheet

  • The final column in the Excel file contains the recommended depreciation rate for each plant account. 
  • A utility may furnish information to support alternative depreciation rates when it applies for a conventional rate case. At the time of the rate case, Commission staff will certify the depreciation rates. ​

​ ​Reference Materials​

Query and Download Water Utility Data

Water Utility Reference Manual

The PSC's Water Utility Reference Manual is designed to help utilities interpret the Uniform System of Accounts, prepare annual reports, and apply tariffed rates properly.​


​​Filing the PSC Annual Report

Utilities use the following PSC systems to file annual reports:​

If you have any questions regarding the PSC Annual Report, please contact: