Water Quality

Naperville’s Water Utility is proud to provide high-quality drinking water that is clean and safe for you and your family to use. In fact, the water supplied by the City complies with all Illinois Environmental Protection Agency (IEPA) standards, including those for lead. For details on the safety of our Lake Michigan drinking water supply, and its compliance with all standards listed in the Safe Drinking Water Act, view our latest Water Quality Report.

The City wants you to be informed as possible when it comes to your drinking water. There is no lead situation affecting the quality of Naperville’s water supply. However, it is possible that construction activities to repair or maintain infrastructure including water mains, lead service lines or water meters may temporarily increase lead levels in the water to your home. Having a lead service line does not necessarily mean you will have lead in your water, but it does indicate that you may be at greater risk if your lead service line is disrupted.

Water Quality Notification Requirements

The City is dedicated to taking proactive steps that help increase water quality awareness and reduce the potential for lead in drinking water.

As part of this commitment, and in compliance with IEPA water quality notification standards, the City provides notice of all water maintenance or replacement work being performed in areas developed prior to 1986. Although the City banned lead water pipes locally in 1960, their use was not prohibited nationally by the U.S. EPA until 1986. Notifying property owners in all areas developed prior to 1986 is one way the City provides proactive information, education and tips to ensure health and safety when it comes to our water supply.

All owners of properties built before 1986 that are affected by water-related construction activity will receive a notice at their door describing the project and listing contact information for questions or concerns. Types of construction activities requiring notice include:

• A water main replacement within one (1) block of your location.
• Repair of a water main break within one (1) block of your location.
• Replacement of your water meter.

Water Service Line Inventory Requirements

The Water Utility has been required under IEPA regulations since 2016 to provide an inventory of the materials used to construct all water service lines in the City. Water Utility personnel use all available source information to determine pipe material, including various City-issued permits, in-person observations and photograph submittals from property owners. If your property was constructed prior to 1986 and you would like an inspection to determine the material of your water service line, please contact Monica O’Loughlin at (630) 305-3775 to schedule an appointment.

The number of lead service lines in the City changes frequently as construction projects progress, individual property owners make upgrades, and outdated water pipes are removed from the system. You can view the most recent lead service line inventory report, as submitted to the IEPA. Scroll to the bottom of the page and type “Naperville” into the search bar to find our report.

Lead Service Line Replacement

The City is currently replacing lead service lines via two main methods:

1. In conjunction with current and future watermain replacement projects across the City.
   • Roughly 25 lead service line replacements were completed in 2021 as part of the Naperville Heights watermain replacement project. 
   • Future watermain replacement projects are anticipated to be budgeted in the following areas: Park Addition, West Highlands, Bay Colony, Mill Ponds, Baileywood, Martin’s Second Addition, River North, Kingston Green, Brush Hill, Indian Hill, Wil-O-Way, Columbia Estates, Bennington, Maplebrook and Hawthorn Square.
2. On an individual basis through the Lead Rebate Program.
   • Provides flexibility to property owners to replace their lead service lines on their own timeframe.

These efforts will be included and tracked in annual lead service line replacement plans, which the City will be required to submit to the IEPA beginning in April 2024.

Learn more about lead service line replacement

Lead Rebate Program

Naperville offers water customers a rebate program to assist with replacing their lead water service lines. Water customers with at least a portion of their water service line that is lead, and who replace the entire length of their water service line, qualify for this program. The amount of the rebate is determined by the side of the street on which the water main is located. Current rebate amounts are $4,250 for a long-side replacement, where the water main is across the street from the affected property; and $2,550 for a short-side replacement, where the water main is in the parkway directly adjacent the affected property.

Interested customers can begin the process by selecting a licensed plumbing contractor to perform the work and applying for a Plumbing Permit (Water Service Replacement/Upgrade) through the Transportation, Engineering and Development department. Upon permit approval, work can commence, with multiple inspections by City staff required throughout the work. Water Utility staff must witness at least a portion of the old water service being lead in order to qualify for the rebate. Upon completion of the water service line replacement and passage of all required permit inspections, payment will be made to the customer in two to four weeks.

For more information or questions, please contact Bill Bolster at (630) 420-4122.

Lead Service Lines in Naperville 

The History

• 1936: Water service lines in Naperville were required by ordinance to be “extra strong lead pipe.”
• 1948: Water service lines in Naperville were required by ordinance to be either “extra strong lead pipe” or “copper pipe.”
• 1960: Water service lines in Naperville were required by ordinance to be “copper pipe” or “cast iron pipe,” depending on their size. Joints in the service lines were still allowed to be “connecting brass with lead.”
• 1986: The U.S. EPA banned the use of lead piping in future construction and restricted lead content in solders and fixtures to 8%. Existing lead pipes were allowed to remain.
• 2014: Lead was banned nationwide in solders and plumbing.
• 2024: Water utilities in Illinois will be required to provide annual lead service line replacement plans to the IEPA.

Naperville’s Water Testing Standards

The City of Naperville’s water supply has consistently tested below minimum acceptable lead levels since 1997 when the City began sampling for lead under the Lead Copper Rule.  Currently, sampling and testing for lead in the Public Water Supply occurs every three years, with the City’s Water Utility collecting and analyzing 50 samples throughout the community for the presence of lead. The last sampling round was done in 2021 with six samples reporting the presence of lead marginally above the detection level of 5 micrograms per liter (parts per billion (ppb)), but below the action level of 15 micrograms per liter (ppb).  A record of the City’s water sampling results can be viewed on the IEPA Drinking Water Watch website.

Lead 101

Knowledge is power. The City is happy to provide these proactive tips for health and safety when it comes to your drinking water.

Determining If You Have a Lead Service Line in Your Home

A licensed plumber can test your water service line to determine if it’s made of lead or another material. Another way to determine if a pipe is made of lead is to carefully scratch it with a coin. If it is lead, the scratched area will turn bright silver.

Reduce Your Risk of Lead Exposure during Construction Projects in Your Neighborhood

Here are some preventive steps you can take to minimize your risk from lead:

• Consider using cold water for drinking, cooking and preparing baby formula. Lead dissolves more easily in hot or warm water. Boiling water will not remove lead.
• Run your water for a few minutes to flush out lead after periods of non-use, such as first-thing in the morning, after work and after a vacation.
• Look for alternative sources of treated water, such as bottled water, or purchase a water filter that is certified to remove “total lead.”
• Periodically remove and clean your faucet aerators, purchase lead-free faucet and plumbing components or replace the entire lead service line.
• Have your water tested. Since you cannot see, taste or smell lead dissolved in water, testing is a good way of telling whether lead is present. While the City does not perform testing in-house, we provide below a list of nearby laboratories certified to perform the testing. You can also find an accredited laboratory near you on the Illinois Environmental Protection Agency’s website. Laboratories will send you bottles for sample collection. Please note that the City is not affiliated with these laboratories, and they will charge you a fee. The certified laboratories closest to Naperville are:
  • First Environmental Laboratories, Inc., Naperville, IL, (630) 778-1200
  • Suburban Laboratories, Inc., Geneva, IL, (724) 580-2575

If you have any questions about water quality and/or lead levels, please contact the Department of Public Utilities – Water at (630) 420-6128.