Rapid and simple lead service line detection screening protocol using water sampling

Area of Science:

• Environmental Science
• Water Quality Management
• Public Health

Background:

• Water systems face challenges in identifying lead service lines (LSLs).
• Accurate detection of LSLs is essential for mitigating lead exposure risks.
• Corrosion control effectiveness varies, impacting lead leaching into drinking water.

Purpose of the Study:

• To evaluate the efficacy of two sampling approaches for predicting lead service lines.
• To compare a simple flushed sampling method with a more invasive sequential profile sampling method.
• To determine the reliability of lead concentration thresholds in identifying LSLs across different corrosion control conditions.

Main Methods:

• Investigated a simple drinking water flushed sampling approach.
• Employed a more complex sequential profile sampling approach.
• Sampled homes with and without existing lead service lines in two communities with varying corrosion control.

Main Results:

• The flushed sampling maximum lead concentration (FMC) accurately predicted 100% of LSL sites in a community with poor corrosion control and 60% in a community with good corrosion control.
• The weighted average sequential profile lead concentration (WASLC) identified the remaining 40% of LSL sites missed by flushed sampling, achieving 100% accuracy.
• WASLC and maximum sequential profile lead concentration demonstrated high reliability in identifying LSLs.

Conclusions:

• Simple flushed sampling can be effective for lead service line detection, particularly in systems with poor corrosion control.
• Sequential profile sampling significantly enhances the accuracy of lead service line identification, especially in systems with effective corrosion control.
• Establishing community-specific lead level thresholds is vital for accurate LSL prediction using water sampling data.