Wisconsin Administrative Code
Public Service Commission
Chapter PSC 185 - Standards For Water Public Utility Service
Subchapter III - Service and Billing
Section PSC 185.31 - Metered service

(1) Except where otherwise authorized by the commission, all water sold by a utility shall be on the basis of meter measurement except that the volume of water used for fire protection, street or sewer flushing, construction, or similar purposes where metering is not practicable may be estimated. (See s. PSC 185.15.)

(2) Wherever practicable, consumption of water within the utility itself, or by administrative units associated with it or with the municipality shall be metered.