Lead in Drinking Water

Data source: U.S. EPA, CDC

What Is Lead Contamination in Water?

Lead does not occur naturally in drinking water sources — it enters tap water through corrosion of lead-containing plumbing materials. Homes built before 1986 are most likely to have lead service lines, lead solder, or brass fixtures that leach lead, especially when water is corrosive (low pH or low mineral content).

Health Effects

Lead is a potent neurotoxin. There is no safe level of lead exposure for children, according to the CDC.

• Children under 6: developmental delays, reduced IQ, learning disabilities, behavioral problems, hearing loss
• Infants: severe developmental harm when formula is prepared with lead-contaminated water
• Adults: high blood pressure, kidney damage, cardiovascular effects
• Pregnant women: increased risk of premature birth, reduced fetal growth

Lead exposure is cumulative — lead is stored in bones and can be released during pregnancy and aging.

How Lead Gets Into Water

Lead contamination is almost entirely a plumbing infrastructure problem, not a source water issue:

• Lead service lines (LSLs) — the pipes connecting the water main to a home; approximately 9 million LSLs remain in service across the U.S.
• Lead solder — used in copper plumbing joints until banned in 1986; older homes commonly have it
• Brass and bronze fixtures — faucets and valves manufactured before 2014 may contain up to 8% lead
• Corrosive water chemistry — low pH, low alkalinity, and certain disinfectants accelerate leaching

The highest lead levels occur in water that has sat in pipes for several hours (first-draw water).

EPA Standards

Lead has no Maximum Contaminant Level (MCL) — instead, the EPA uses an action level system under the Lead and Copper Rule:

• Action Level: 0.015 mg/L (15 ppb) — if 10% of sampled homes exceed this, the utility must take corrective action
• Treatment Technique Trigger: 0.010 mg/L (10 ppb) — triggers additional requirements under the 2024 Lead and Copper Rule Improvements (LCRI)
• LCRI (2024): requires all lead service lines to be replaced within 10 years regardless of water quality test results

Under the 2024 rule revisions, utilities must inventory all service line materials and provide annual notifications to customers served by lead lines.

How to Remove Lead From Drinking Water

Flushing cold water for 30–60 seconds before use reduces exposure but does not eliminate it. For reliable removal:

• Reverse osmosis (RO) — removes 95–99% of lead; NSF 58 certified
• Carbon block filters — must be NSF 53 certified specifically for lead; pitcher and faucet filters vary widely in effectiveness
• Distillation — effective but slow and energy-intensive
• NSF 53 pitcher filters (e.g., certain ZeroWater, Brita, PUR models) — check the specific product's NSF certification document, not just the packaging claim

Do not use hot tap water for drinking or cooking — hot water leaches lead faster.

Lead in U.S. Water Systems: What the Data Shows

ZipCheckup aggregates CCR data and EPA enforcement records to track lead contamination across the country:

• 41 water systems serving 1,153 ZIP codes reported lead detections in their most recent Consumer Confidence Reports
• 1,868 EPA enforcement actions for lead have been recorded across 364 ZIP codes
• In total, lead-related data affects 1,517 ZIP codes in our database

Lead is regulated under the action level system (15 ppb), not a traditional MCL — so even a single exceedance triggers mandatory corrective action by the utility.

Federal LSL Inventory (LCRR / 2026Q1)

Under the federal Lead and Copper Rule Revisions, every public water system must inventory the service lines connecting buildings to the water main and submit counts to its state primacy agency, which forwards them to the EPA. ZipCheckup integrates the 2026Q1 EPA SDWIS Federal Service Line Inventory release with state-portal LCRR datasets from NJDEP, MassDEP, FDEP, and NY DOH:

• 66,449 water systems in the integrated LSL dataset, covering 24,288 ZIP codes across all 50 states plus territories
• 1,952,290 confirmed lead service lines reported nationally — concentrated in Illinois (413,224), Ohio (265,118), Michigan (199,943), Indiana (169,436), and Wisconsin (147,022)
• 995,332 galvanized lines flagged as requiring replacement under LCRR
• 22,224,258 service lines with unknown material status — under LCRR these must be inventoried by 2027
• 30,795 individual water-system pages on ZipCheckup now surface this inventory data, including federal regulatory status (LCRR submission flag, ALE sample date, Rule 2E/4G violation flags) where reported

The 2024 LCRR finalization requires every confirmed lead and galvanized service line to be replaced within 10 years. To find inventory data for a specific water system, search by ZIP code or browse by state below.

Is Lead a Problem in Your Area?

Lead violations and action level exceedances are reported to the EPA SDWIS database. Older cities with pre-1986 housing stock — including Detroit, Chicago, Pittsburgh, and Newark — have documented elevated lead levels. However, any home with older plumbing is potentially at risk regardless of the utility's system-wide results.

ZipCheckup pulls EPA SDWIS violation data by ZIP code, including lead-specific monitoring results where available.