Water Operations


The City of Sun Prairie is served by seven deep wells throughout the city. The well depths range from 860 feet to 905 feet. Combined pumpage is 8750 gallons per minute. All wells are checked and monitored daily, and water is treated with chlorine and fluoride before entering the water system. Water samples and test results are sent to the State according to the Wisconsin Department of Natural Resources requirements. Read the most current Water Quality Report here.

Water storage for the Sun Prairie water system includes three in-ground reservoirs and three elevated water tanks, holding total reserve capacity of 2.8 million gallons. This is less than the peak 1-day pumpage of 3.5 million gallons of water from July 6, 2010.

Sun Prairie Utilities maintains approximately 166 miles of water main throughout the city. We try to schedule some aged water main replacement every year to keep our system safe and robust. Water mains can break with the ground shifting pressures of rapid changing temperatures, or age. Sometimes breaks are man-made with construction projects. If you see water bubbling from the street, please note the location and call our office at 837-5500.

Requests to locate and/ or exercise curb valves will be scheduled and require 2 business day's notice.


Our water crew maintains nearly 1,800 public fire hydrants within the Sun Prairie water system. These hydrants are a critical component to the City’s public safety. Please maintain proper clearance around any fire hydrant so as to not impede City of Sun Prairie Emergency Service personnel from access in the case of an emergency. Please keep items, shrubbery, and snow clear of all hydrants.


Hydrant flushing is a release of water from fire hydrants. It is a controlled procedure that is vital to the general maintenance of Sun Prairie’s water distribution system.

Some utilities flush quite often, as much as monthly due to high mineral content, stagnant water, or other reasons. Fortunately, Sun Prairie does not have many iron or mineral issues. Sun Prairie Utilities flushes hydrants at least every other year as required by Wisconsin State code NR 810.13. In areas where water may move more slowly through the system, such as hydrants located on a dead-end main, hydrants are flushed twice annually to maintain water quality.

Primarily Sun Prairie Utilities flushes to operate and inspect each hydrant to ensure proper performance when needed and to replace damaged hydrants.

Visit our Hydrant Flushing FAQs for more information

Hydrant Meters

Sun Prairie Utilities will place, for a fee, a meter on a hydrant for temporary private use. Examples include filling an in-ground pool or new construction landscaping. The hose is not provided and cannot cross a city street. Requestors will be charged for the applicable set fee and any water usage through the meter. Current fees are listed on the Hydrant Meter Request Form. All hydrant meters must be set and removed by SPU employees and require appropriate backflow protection. To request a hydrant meter, fill out the Hydrant Meter Request Form and return it to the Sun Prairie Utilities business office at 125 West Main Street or email it to: hydrant_meters@myspu.org

Water Meter Upgrades

Electric and water meter ownership.

Our over 12,000 water meters are located inside almost every building in Sun Prairie, usually in the basement, to prevent freezing and damage. Some properties have an outside reader (OR) to allow an SPU meter reader to read the water meter every month without needing to access the inside meter or inconvenience our customers to gain entry.

Sun Prairie Utilities crew members are presently working to convert all water meters to a two-way communication device. SPU is transitioning to an Advanced Metering Infrastructure (AMI) smart meter where data collection devices read your meter from a distance and store that information in a format that is then downloaded into our billing software to help produce your monthly billing statement.

Sun Prairie Utilities is required by the State of Wisconsin to conduct periodic testing and maintenance on meters by a specific schedule. Please be cooperative and responsive if you receive a phone call or letter requesting an appointment to gain access to the meter inside your property. We will only need a few minutes inside to check or replace the meter.