Lead in Drinking Water

Lead has no safe level in drinking water. Every Consumer Confidence Report must include a specific educational statement about lead — one of the few pieces of boilerplate that federal law mandates verbatim.

How lead gets into drinking water

Lead does not come from source water in most cases. It enters drinking water after treatment, through corrosion of lead service lines (the pipes connecting the water main to a home or building) and through lead-containing solder, fittings, and fixtures in household plumbing.

The chemistry matters here: water that is slightly acidic or low in minerals can strip lead from plumbing materials it contacts. This is why corrosion control — adjusting pH, adding phosphate or other inhibitors — is the primary regulatory lever the Lead and Copper Rule targets. When corrosion control fails or was never optimized, lead dissolves into water that has been sitting in contact with lead materials, sometimes at levels far above the action level.

Older housing stock concentrates the risk. Lead service lines were common before 1986, when the Safe Drinking Water Act amendments banned their installation. Lead solder was widely used before 1988. A home built before 1986 may have a lead service line even if the utility's distribution mains are lead-free. The utility may not own, and until recently had no obligation to inventory, the portion of a service line on the customer's side of the meter.

The Lead and Copper Rule Improvements (LCRI), finalized October 8, 2024 and published in the Federal Register on October 30, 2024 (89 FR 86416), require utilities to inventory all service lines — including the customer-side portion — and replace lead and galvanized-requiring-replacement (GRR) service lines within ten years of the November 1, 2027 compliance date. See the lead service lines page for the disclosure and inventory requirements.

Health effects

Who is most at risk

Lead is a neurotoxin with no known threshold for harm. The EPA has set the Maximum Contaminant Level Goal (MCLG) for lead at zero — meaning there is no concentration in drinking water that is established as safe. (40 CFR § 141.51.) The MCLG of zero reflects the judgment that no level of lead exposure is without risk, particularly for developing children and fetuses.

Children under six face the greatest developmental risk. Lead exposure during early childhood impairs cognitive development, reduces IQ, and affects behavior and attention. These effects are largely irreversible. Infants fed formula mixed with tap water are at elevated risk because formula can constitute a significant share of their total fluid intake.

In adults, lead exposure at elevated levels is associated with increased blood pressure, kidney damage, and cardiovascular disease. Pregnant people face additional risk: lead stored in bone can be remobilized during pregnancy and transferred to the fetus.

Mandated health-effects language

Federal regulations require every CCR to include the following lead-specific educational statement. The full required text — set out in Figure 1 to 40 CFR § 141.154(d)(1) (Cornell LII) — reads:

"Lead can cause serious health effects in people of all ages, especially pregnant people, infants (both formula-fed and breastfed), and young children. Lead in drinking water is primarily from materials and parts used in service lines and in home plumbing. [INSERT NAME OF SYSTEM] is responsible for providing high quality drinking water and removing lead pipes but cannot control the variety of materials used in the plumbing in your home. Because lead levels may vary over time, lead exposure is possible even when your tap sampling results do not detect lead at one point in time. You can help protect yourself and your family by identifying and removing lead materials within your home plumbing and taking steps to reduce your family's risk. Using a filter, certified by an American National Standards Institute accredited certifier to reduce lead, is effective in reducing lead exposures. Follow the instructions provided with the filter to ensure the filter is used properly. Use only cold water for drinking, cooking, and making baby formula. Boiling water does not remove lead from water. Before using tap water for drinking, cooking, or making baby formula, flush your pipes for several minutes. You can do this by running your tap, taking a shower, doing laundry or a load of dishes. If you have a lead service line or galvanized requiring replacement service line, you may need to flush your pipes for a longer period. If you are concerned about lead in your water and wish to have your water tested, contact [INSERT NAME OF SYSTEM and CONTACT INFORMATION]. Information on lead in drinking water, testing methods, and steps you can take to minimize exposure is available at https://www.epa.gov/safewater/lead."

— 40 CFR § 141.154(d)(1), Figure 1

Utilities may use an alternative educational statement with primacy agency approval (40 CFR § 141.154(d)(2)), but the default is the verbatim figure above.

How lead is regulated: LCR, LCRR, LCRI

Lead in drinking water has been regulated under the federal Lead and Copper Rule (LCR) since 1991. The rule has been revised twice since then — understanding all three versions is important because utilities are currently in a compliance transition.

LCR (1991): Established the original framework — action level of 15 µg/L (15 parts per billion), 90th-percentile tap sampling methodology, corrosion control treatment requirements, and public education obligations. The foundational structure of the lead rule still traces back to this version. (40 CFR Part 141 Subpart I.)

LCRR (Lead and Copper Rule Revisions, 2021): Finalized in January 2021. Required utilities to complete initial service line inventories by October 16, 2024. Strengthened sampling protocols and corrosion control trigger levels. The LCRR was finalized but, critically, its broader compliance date was pushed ahead by the LCRI before it ever took full effect.

LCRI (Lead and Copper Rule Improvements, 2024): Replaces the LCRR before the LCRR's compliance date arrived. Finalized October 8, 2024; published October 30, 2024. Full compliance required by November 1, 2027. The LCRI lowers the lead action level from 15 µg/L to 10 µg/L, mandates full lead service line replacement within ten years, and introduces paired 1st-and-5th-liter tap sampling at lead service line sites.

For a side-by-side comparison of all three rules, see the LCR vs. LCRR vs. LCRI glossary entry.

The CCR disclosure obligations sit separately from the monitoring rule. CCR requirements are codified at 40 CFR Part 141 Subpart O, §§ 141.151–141.156. The monitoring and corrosion control requirements live at 40 CFR Part 141 Subpart I. Both apply to community water systems. See the LCRI 2027 explainer for a full timeline of upcoming compliance milestones.

What the action level means

The action level (AL) for lead is not a Maximum Contaminant Level (MCL). That distinction matters.

An MCL is an enforceable limit: if a contaminant exceeds its MCL in the water leaving the treatment plant, the system has violated the standard. Lead works differently. The action level is a trigger: if the 90th percentile of tap water samples at high-risk sites exceeds the action level, the utility must take specified actions — optimizing corrosion control, increasing public education, replacing more lead service lines. Exceeding the action level is not itself an MCL violation; it triggers a response requirement.

Under the original LCR and the LCRR, the lead action level was 15 µg/L (micrograms per liter, equivalent to 15 parts per billion). Beginning November 1, 2027, the LCRI lowers it to 10 µg/L. (40 CFR § 141.80, as amended by LCRI; 89 FR 86416.) This is a meaningful reduction — a utility that was below the trigger under the LCR may find itself subject to action level response requirements under the LCRI with the same tap water results.

The action level is evaluated using the 90th percentile of samples collected at first-draw locations. Under the LCRI, systems sampling at lead service line sites must collect paired first-liter and fifth-liter samples and use the higher of the two values when calculating the 90th percentile. (89 FR 86416.)

The MCLG for lead remains zero — unchanged by any of the rule revisions. The gap between the MCLG (zero) and the action level (now 10 µg/L) is not a policy inconsistency; it reflects the reality that achieving zero lead in tap water is not technically achievable under current infrastructure conditions. The action level is set at the level where regulatory response mechanisms become triggered, not at the level of zero risk.

Lead service lines

A lead service line (LSL) is the pipe running from the water main to a home or building. These pipes are the largest single source of lead in drinking water. When a system tests tap water and finds elevated lead, the presence of a lead service line at that site is the most likely cause.

The LCRI requires every community water system to:

1. Complete and maintain a full service line inventory that classifies each service line as lead, galvanized requiring replacement (GRR), non-lead, or lead-status unknown.
2. Replace all lead and GRR service lines within ten years of November 1, 2027.
3. Replace the full service line — both the utility-owned portion and the customer-owned portion — when conducting a replacement under the LCRI's mandatory timeline. Full replacements are required; partial replacements that leave lead on either side of the meter are prohibited.

For details on what the CCR must disclose about lead service line inventories and replacement plans, see Lead Service Lines and Your CCR.

What you can do as a consumer

If you are a water consumer reading your CCR and you have concerns about lead:

Run the tap before drinking. If water has been sitting in pipes for several hours (overnight, or while you were away), flush for several minutes before drinking or cooking. Running the shower, doing laundry, or running the dishwasher accomplishes the same thing. If you have a lead service line, flush longer.

Use only cold water for drinking and cooking. Hot water dissolves lead from plumbing faster than cold water. Never use hot tap water for infant formula, cooking, or drinking. Boiling water does not remove lead — it concentrates it.

Use a certified filter. Pour-over and under-sink filters certified by an American National Standards Institute (ANSI) accredited certifier to NSF/ANSI Standard 53 (for lead reduction) are effective at reducing lead in tap water. Follow the manufacturer's replacement schedule; an expired filter cartridge can release lead back into water.

Find out if your home has a lead service line. Under the LCRI, utilities must publish their service line inventories in a format accessible to the public. Contact your water utility to ask whether your address has a lead, GRR, or unknown-material service line. If you rent, your landlord may have this information.

Get your water tested. If you have specific concerns — you live in an older home, you are pregnant, or you have a young child — you can request testing through your water utility or a certified laboratory. Your CCR will list contact information for your utility.

What utilities must disclose on the CCR

Water utilities have two distinct lead-related disclosure obligations in the CCR:

1. The mandatory health-effects educational statement at 40 CFR § 141.154(d). Every system must include this statement regardless of whether lead has been detected. The full required text is reproduced in the "Health effects" section above.

2. Monitoring results and action level status. If your system detects lead in tap water monitoring, you must report results in the CCR's contaminant table, including the 90th percentile value and the number of sample sites exceeding the action level. The reporting format follows 40 CFR § 141.153.

3. Service line inventory statement. Since the 2024 CCR Rule revisions (effective June 24, 2024; 89 FR 46013), every CCR must include a statement confirming that a service line inventory has been prepared and must direct consumers to where they can access it. This requirement is at 40 CFR § 141.153(h)(8). If your system has no lead, GRR, or unknown-material service lines, the inventory itself may be a written statement to that effect — but the CCR reference to the inventory is still required.

The interaction between these three elements means that lead generates more CCR content than almost any other contaminant: a health-effects block, a monitoring data table, and an inventory disclosure, regardless of whether any exceedance has occurred.

For California water systems, the State Water Resources Control Board Division of Drinking Water may have additional guidance on CCR presentation of lead data. Consult your primacy agency before finalizing lead-related content.

Last reviewed: 2026-05-03. Next scheduled review: every 6 months or after LCRI implementation milestones.