Illinois’ capital city draws its drinking water from a man-made lake — and between PFAS from nearby military activity, aging lead pipes, and source water pressures, Springfield residents have reasons to pay attention.
Where Springfield Gets Its Water
City Water, Light and Power (CWLP) provides drinking water to Springfield and surrounding areas, serving roughly 120,000 people. The primary source is Lake Springfield, a man-made reservoir created in 1935 by damming Sugar Creek. The lake covers about 4,200 acres and serves double duty as a drinking water source and cooling water supply for CWLP’s coal-fired power plant. [NEEDS VERIFICATION: current status of CWLP’s coal plant operations]
That dual use has raised questions over the years. Thermal discharge from the power plant warms the lake, which can promote algal growth and affect water chemistry. Agricultural runoff from the surrounding watershed adds nutrients that fuel those algal blooms.
CWLP operates a conventional surface water treatment plant with coagulation, sedimentation, filtration, and chloramine disinfection.
PFAS: The Capital Airport Connection
Abraham Lincoln Capital Airport, located just southeast of Springfield, has a history of using aqueous film-forming foam (AFFF) for firefighting training — the same foam that’s contaminated groundwater near airports and military bases across the country.
PFAS compounds from AFFF are remarkably persistent. They don’t break down in the environment, and they migrate through soil into groundwater. Testing near the airport has detected PFAS in groundwater and nearby monitoring wells. [NEEDS VERIFICATION: specific PFAS levels detected near Capital Airport and whether contamination has reached Lake Springfield or its tributaries]
The Illinois EPA has been involved in assessment of PFAS contamination at the airport site. The concern for Springfield residents is whether PFAS from the airport — or other sources in the watershed — are making it into Lake Springfield and, ultimately, into treated drinking water.
CWLP has conducted PFAS testing of its treated water. Results should be available through the utility’s Consumer Confidence Report and the EPA’s UCMR (Unregulated Contaminant Monitoring Rule) data. As the EPA’s 2024 PFAS maximum contaminant levels take effect, Springfield’s system will need to demonstrate compliance.
Lead Pipes: Springfield’s Underground Problem
Springfield’s housing stock is old. The city was founded in 1821, and much of its residential infrastructure dates from the late 1800s through the mid-1900s. That means lead service lines — lots of them.
Illinois as a whole has a massive lead service line problem. The state is estimated to have over 680,000 lead service lines, second only to — or possibly exceeding — the number in any other state. [NEEDS VERIFICATION: Illinois’ current ranking in lead service line count] Chicago gets most of the attention, but cities like Springfield, Peoria, and Rockford all have significant inventories.
CWLP uses corrosion control treatment to minimize lead leaching from pipes, and the system’s Lead and Copper Rule results have shown 90th percentile levels below the action level. But again, that aggregate number can hide individual homes with much higher readings.
The city has been working on a lead service line inventory as required by the EPA’s revised Lead and Copper Rule Improvements. Replacement timelines depend on funding — and Springfield, like many mid-sized cities, faces budget constraints.
Industrial History and Source Water
Springfield’s industrial past includes rail yards, manufacturing facilities, and chemical storage operations. Several contamination sites in Sangamon County are tracked by the Illinois EPA, including sites with known groundwater contamination from VOCs and petroleum products.
While CWLP draws from Lake Springfield rather than groundwater, the lake’s watershed isn’t immune to contamination. Stormwater runoff carries pollutants from roads, parking lots, agricultural fields, and developed areas into the lake’s tributaries.
The lake also receives treated wastewater discharge from the Springfield Metro Sanitary District, which adds another potential source of pharmaceuticals, personal care products, and other emerging contaminants that conventional treatment may not fully remove. [NEEDS VERIFICATION: current discharge points into Lake Springfield watershed]
Algal Blooms and Source Water Quality
Lake Springfield has experienced harmful algal blooms (HABs), particularly during warm summer months. These blooms can produce cyanotoxins — notably microcystin — that pose health risks if they make it through the treatment process.
Factors contributing to algal blooms in the lake include:
- Nutrient loading from agricultural runoff (nitrogen and phosphorus)
- Thermal discharge from the power plant
- Shallow depth in parts of the reservoir
- Climate change extending warm-water seasons
CWLP monitors for cyanotoxins and adjusts treatment when blooms occur. The EPA established a health advisory level for microcystin in drinking water, and Illinois has monitoring requirements for public water systems using surface water sources susceptible to HABs.
What the Data Shows
EPA’s ECHO database shows CWLP’s general compliance with Safe Drinking Water Act standards. The system’s most recent Consumer Confidence Reports indicate:
- Lead and copper — 90th percentile below action levels, with corrosion control in place
- Disinfection byproducts — TTHMs and HAA5 detected but below MCLs; chloramine disinfection generally produces fewer byproducts than free chlorine
- Nitrates — present in source water from agricultural runoff but below the MCL after treatment
- Turbidity — generally well-controlled, with occasional spikes during heavy rain
The emerging concern is PFAS, and how Springfield’s numbers stack up against the new federal limits will become clearer as compliance testing ramps up.
What Springfield Residents Should Do
Check for lead service lines. Contact CWLP to find out if your home has a lead service line. Homes built before 1986 are most at risk. Even newer homes may have lead solder in the plumbing.
Test your tap water. Don’t rely solely on the utility’s system-wide results. Individual home testing can reveal problems specific to your plumbing. CWLP may offer free lead testing kits — contact them to find out.
Flush your pipes. Run the cold water for 30 seconds to 2 minutes before using it for drinking or cooking, especially first thing in the morning or after the water has sat for several hours.
Watch for algal bloom advisories. During summer months, pay attention to any advisories about Lake Springfield. While the treatment plant addresses cyanotoxins, extra caution doesn’t hurt.
Consider point-of-use filtration. An NSF/ANSI 53-certified filter handles lead. For broader protection including PFAS, a reverse osmosis system is your best option. Activated carbon filters (including pitcher filters) can reduce some PFAS compounds and improve taste.
If you’re concerned about your water quality, a certified water treatment professional can test your water and advise on solutions.