The Lead and Copper Rule has governed how public water systems monitor and control lead and copper in drinking water since 1991. The EPA’s Lead and Copper Rule Revisions (LCRR) introduce the most significant updates to these regulations in over three decades, establishing stricter standards, new inventory requirements, and expanded monitoring obligations that affect water systems of all sizes.

This guide walks through the key provisions of the LCRR and how to build a monitoring program that meets the new compliance requirements.

Key Changes in the Lead and Copper Rule Revisions

The LCRR represents a fundamental shift in how the EPA approaches lead contamination in drinking water. Rather than relying primarily on treatment optimization at the plant level, the revised rule emphasizes proactive identification and removal of lead sources throughout the distribution system.

The most significant changes include:

• Lowered trigger level: The lead trigger level has been reduced from 15 parts per billion (ppb) to 10 ppb. When the 90th percentile of tap water samples exceeds this trigger level, the water system must take corrective action, including accelerated lead service line replacement. The previous action level of 15 ppb remains in place as a separate threshold that triggers additional requirements.
• Mandatory lead service line replacement: Systems that exceed the trigger level must replace lead service lines at a rate determined by the severity of the exceedance. Even systems that do not exceed the trigger level are required to replace lead service lines at a baseline rate over time, reflecting the EPA’s position that no level of lead exposure is safe.
• Enhanced monitoring and reporting: The LCRR expands the scope of required monitoring, including new sampling protocols, larger sampling pools, and more frequent reporting to state primacy agencies. Systems must also monitor at locations that are most likely to have elevated lead levels, rather than relying on historical sampling sites that may underestimate system-wide risk.
• Mandatory public notification: Water systems must directly notify consumers served by lead service lines within a specified timeframe. This includes providing information about the health risks of lead exposure and steps residents can take to reduce exposure while service line replacement is pending.
• School and daycare testing: The LCRR introduces new provisions requiring water systems to conduct lead testing at schools and licensed childcare facilities within their service area. This represents a significant expansion of the rule’s scope and acknowledges the particular vulnerability of children to lead exposure.

These changes apply to all community water systems and non-transient non-community water systems across the country. The scale of the requirements varies based on system size, but no system is exempt from the core provisions.

Service Line Inventory Requirements and Deadlines

One of the most consequential provisions of the LCRR is the requirement for all water systems to develop and maintain a comprehensive inventory of their service line materials. This inventory forms the foundation for every other aspect of LCRR compliance, from identifying high-risk sampling locations to prioritizing service line replacement projects.

Inventory Classification Categories

Under the LCRR, every service line in a water system’s distribution network must be classified into one of four categories:

• Lead: Service lines confirmed to be made of lead, including lines with lead goosenecks, pigtails, or connectors.
• Galvanized requiring replacement (GRR): Galvanized service lines that are or were downstream of a lead service line. These lines can leach accumulated lead even after the upstream lead line has been replaced.
• Non-lead: Service lines confirmed to be made of copper, plastic, or other non-lead materials.
• Lead status unknown: Service lines for which the material cannot be determined based on available records or investigation. The LCRR requires systems to actively work to resolve unknown classifications over time.

Key Deadlines

The initial service line inventory deadline was October 2024. Water systems were required to submit their inventories to their state primacy agency by this date. Following the initial submission, inventories must be updated annually to reflect newly verified materials, completed replacements, and reclassifications.

For systems that exceed the lead trigger level, the LCRR establishes mandatory replacement timelines based on the severity of the exceedance. Systems must prioritize replacement in areas serving vulnerable populations, including schools, childcare facilities, and environmental justice communities.

Updated Sampling Protocols and Action Levels

The LCRR introduces substantial changes to how water systems collect and evaluate lead and copper samples. These changes are designed to produce a more accurate picture of lead exposure risk throughout the distribution system.

Fifth-Liter Sampling

Under the original Lead and Copper Rule, samples were collected from the first liter of water drawn from the tap after a period of stagnation. The LCRR changes this to fifth-liter sampling at locations served by lead service lines. The fifth liter is more representative of water that has been in contact with the lead service line itself, rather than interior plumbing, providing a better measure of the lead contribution from the service line.

Expanded Sampling Pool

The revised rule requires systems to draw samples from a wider pool of locations. Sampling sites must include locations with lead service lines, and systems can no longer rely on a small set of historical sampling points. This prevents undersampling of high-risk locations.

Compliance Calculations

The LCRR maintains the 90th percentile calculation for compliance. However, the combination of a lower trigger level (10 ppb), fifth-liter sampling, and a broader sampling pool means many systems previously in compliance may exceed the new thresholds.

Find-and-Fix Provisions

An important addition in the LCRR is the find-and-fix requirement. When any individual sample exceeds 15 ppb, the water system must investigate the cause and take corrective action at that specific location, regardless of whether the system-wide 90th percentile exceeds the trigger level. This provision ensures that isolated high-lead locations receive attention even in systems that are otherwise in compliance.

Small System Flexibilities

The LCRR includes flexibilities for small water systems (generally those serving fewer than 10,000 people), such as alternative monitoring schedules and additional time to complete inventories. However, small systems are not exempt from the core provisions and must ultimately achieve compliance.

How to Build a Compliant Lead and Copper Monitoring Program

Meeting the requirements of the LCRR demands a systematic approach. The following steps outline how water systems can build a monitoring program that satisfies the new regulations and protects public health.

Step 1: Complete Your Service Line Inventory

If your system has not yet completed its service line inventory, this should be the immediate priority. Begin with a comprehensive records review, including construction records, meter installation records, and historical inspection reports. Supplement records research with field verification using methods such as visual inspection, scratch testing, and predictive modeling based on construction era and neighborhood characteristics.

Step 2: Establish Sampling Sites Per New Protocols

Work with your state primacy agency to identify and approve sampling sites that meet the LCRR’s expanded requirements. Prioritize locations with confirmed lead service lines, and ensure your sampling pool is geographically representative of your entire service area. Document the rationale for each site selection to support future regulatory reviews.

Step 3: Partner with an Accredited Laboratory

Look for a lab that holds ISO 17025 accreditation and is approved to perform EPA Method 200.8 for lead and copper in drinking water. Accreditation ensures validated procedures, rigorous quality control, and defensible data.

AATLS provides lead and copper testing using EPA Method 200.8 with detection limits well below the LCRR trigger and action levels, equipped to handle both routine monitoring and large-scale sampling events.

Step 4: Implement Your Monitoring Schedule

The LCRR specifies monitoring frequencies based on system size and compliance history. Standard monitoring typically occurs on a semi-annual basis, though systems with consistently low results may qualify for reduced monitoring after demonstrating sustained compliance. Build a monitoring calendar that accounts for sampling windows, laboratory turnaround times, and reporting deadlines to avoid gaps in your compliance record.

Step 5: Develop a Communication Plan for Results

Prepare templates for notifying residents served by lead service lines, protocols for reporting results to state agencies, and procedures for responding to high-lead results under find-and-fix provisions. Transparent communication builds public trust.

How AATLS Supports Your Compliance Program

AATLS works with water systems across the country to meet LCRR compliance requirements. Our services include:

• EPA Method 200.8 analysis for lead and copper with rapid turnaround
• Sampling kits and collection guidance tailored to LCRR protocols
• Data reporting formatted for state primacy agency submissions
• Technical consultation on monitoring program design
• Volume pricing for large-scale sampling events

You can submit a sample through our streamlined process or place orders directly at orders.aatls.com.