Data Updates

December 2020 Data Update

Updated on 01/10/2021

The data for the July to December six-month monitoring period indicate that water quality in University Park has been restored.

In December 2020 alone, 98 percent of all compliance-sampled homes were at or below the Environmental Protection Agency’s threshold for lead, 15 micrograms per liter (ug/L), and the 90th percentile value was just 4 ug/L. This means that we achieved the government benchmark for water quality in University Park for three months in a row.

State and federal drinking water regulations require that 90 percent of regularly sampled homes have lead levels of 15 ug/L or less as measured over six-month monitoring periods – and data indicate that we achieved the 90th percentile benchmark for the July to December period.

As of December 2020, 91 percent of samples collected in the monitoring period were at or below the EPA’s threshold for lead.

.To view a table listing all compliance sample results for each sampled home from the July to December 2020 sampling events, please see here.

Achieving the 90th percentile benchmark for the six-month monitoring period is a significant water quality milestone that we have been working towards since day one, and we thank our customers and community partners for helping us get here.

It is important to note that this milestone reaffirms that our treatment is working. As the following graphic illustrates, the treatment establishes a protective coating inside customers’ home plumbing. The protective coating stops lead inside impacted customers’ internal plumbing from interacting with fresh water flowing into their homes.

As we continue working closely with state regulators and national experts on our approach to maintaining the water quality, University Park customers should continue to use their tap water normally throughout the home and use cold tap water at their kitchen sinks.

We thank our customers for their ongoing patience and cooperation and look forward to continued collaboration to rebuild trust in the community. As we move forward, together, we will continue to be here for our customers.

Customers can call 877.987.2782 at any time to request water sampling.

See below for more information about compliance sampling and our process or click here to view previous 2020 data updates or here to view 2019 data updates.

Archived Data Updates

Click the button below to view previously posted data updates. 

More Information About Compliance Sampling

Compliance Sampling in University Park

IEPA regulations require us to work with at least 40 homes and businesses in the University Park service area to conduct compliance sampling. Regulations require us to conduct sampling twice annually. Sample locations must be submitted to the IEPA before compliance sampling can begin.

We collected regularly scheduled samples in May 2019 as part of our biannual compliance testing schedule. On June 13, 2019, we began receiving those sampling results, some of which showed elevated lead levels. As a result, we began working with the IEPA on a treatment plan and voluntarily increased the sampling frequency, which now includes conducting monthly sampling, to help us understand and monitor progress as we resolve this issue.

All sample locations in the sampling pool were built before 1990, which means they likely have lead in their internal plumbing and represent “high-case” scenarios.

To complete compliance sampling, we schedule appointments with participating customers and a member of our team collects the samples after customers’ water has been unused for six or more hours. We then send the samples to an independent lab for testing.

What we Believe Happened and how we are Working to Fix it

We immediately issued a voluntary do-not-consume advisory on June 14, 2019 for all customers in the service area to be as protective as possible after receiving compliance samples that showed elevated lead levels in 14 homes on June 13, 2019. Thereafter, we investigated and gathered information about this situation. It is important to note that no state or federal regulation required us to issue the do-not-consume advisory and that we issued it as a precaution to protect the public until we learned more about the extent, cause and level of the issue AND until we could implement alternative protective health measures. We have since transitioned to a lead advisory to provide more useful guidance to customers. We are continuing our public education efforts, so impacted customers know the protective steps to take to consume their water.

We have identified that the likely cause of elevated lead levels is due to water chemistry interacting with lead solder in customers’ internal plumbing. Our information shows that the water in our distribution system and the University Park infrastructure do not have elevated levels of lead.

The EPA banned lead solder in 1986, and compliance testing results in post-1990 University Park homes have shown lead levels meet the EPA action level. We have since removed some areas from the advisory based on property age and water sample results. While not required, we still recommend customers whose properties have been lifted from the advisory run their tap water for two to three minutes and until they notice a temperature change before consumption. This ensures they receive fresh water from the mains in the street rather than water that has been sitting stagnant in their internal plumbing.

On June 15, 2019, we introduced a new treatment, orthophosphate (or, more specifically, a 90/10 phosphate blend), into the water system in the entire service area. This treatment is known for its ability to create a protective coating where lead is present, keeping the lead out of the water we consume. The treatment can take months to become effective. It is important to note that this treatment is not harmful to humans or pets.

A Message from the IEPA

The Centers for Disease Control and Prevention indicates there is no safe blood lead level in children. Lead exposures come from a combination of environmental sources, which may include lead in water. U.S. EPA estimates that water can make up 20 percent or more of a person’s total exposure to lead, and infants who consume mostly mixed formula can receive 40-60 percent of their exposure to lead from drinking water. The source of lead in water is most often from a building’s plumbing system.

The IEPA and Illinois Department of Public Health support point-of-use (POU) filters as a short-term strategy for reducing lead in drinking water. (Please note: Aqua Illinois is providing free faucet filters and pitcher filters to customers in University Park). A POU system filters water at the point where water is being used and is installed at the water connection, typically under the sink in the kitchen or bathroom. Water pitchers with POU filters may also be used. POU filters are commercially available and can be effective at removing most lead. There are several POU cartridge filter units on the market. They can vary in price and effectiveness. Filters should routinely be replaced or maintained in accordance with manufacturers guidelines and recommendations to remain effective.

To select a lead-reducing POU filter, check with the manufacturer or a third-party website (such as to verify the product was tested and certified for lead removal (NSF/ANSI Standard 53). For additional protection for particulate lead, look for a POU filter that is also certified against NSF/ANSI Standard 42 (for class I particulate reduction, 0.5 micrometers to less than 1 micrometers). To be effective, the POU filters should be installed at locations used for drinking water or for food preparation according to the manufacturer’s instructions. This includes kitchen water faucets and refrigerators with water dispensers and ice makers or in water pitchers.

POU filters should be considered an interim measure until [effective treatment is restored, or] the sources of lead have been removed and replaced with lead free plumbing materials. After replacement of lead plumbing materials or disturbance of a plumbing system, the plumbing system should be flushed for 30 minutes with aerators and screens removed from all faucets. Because you cannot see, smell, or taste lead in water, testing the water is the only way to determine if lead is present in drinking water.

To access additional information about lead in drinking water and a consumer tool for identifying POU filters certified to reduce lead, please visit U.S. EPA’s website at and

Lead in homes can also come from sources other than water. To access more information about other sources of lead, please visit IDPH’s website at:

Consider contacting your doctor to have your children tested if you are concerned about lead exposure.

The Lead and Copper Rule and Compliance Sampling Requirements

The EPA, through its Lead and Copper Rule, requires water utilities to work with their customers to collect regularly scheduled stagnation samples, or compliance samples. These samples must be taken after water has remained in customers’ pipes unused for six or more hours, therein providing high-case scenario data for lead exposure. Under the rule, utilities must choose sample locations that represent properties with the highest inventory of lead. For example, so-called “Tier 1” locations include those with lead service lines or lead solder on copper pipes within homes constructed after 1982.

The Lead and Copper Rule does not set a health-based lead limit; it is a treatment-based rule, which means if 90 percent of compliance samples test below 15 ug/L, treatment is deemed effective, and any samples with lead levels above 15 ug/L are analyzed on an individual basis.

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