Role of Water Chemistry in Lead Release during Drinking Water Supply and Augmentation
type: CreativeWork
description: Lead is a toxic heavy metal and legacy contaminant in drinking water that can be released from lead service lines and lead-containing premise plumbing. Lead concentrations in water are sensitive to changes in water chemistry. The extent of lead release is often driven by the solubility of the corrosion products formed on the interior of the pipes. Therefore, it is critical to advance our understanding of the extent of lead released from different lead-based plumbing materials at equilibrium and the ability to control lead when it exceeds the regulatory levels. Lead measured in the 1st liter of water collected from a tap can be significantly different from the lead measured in the water parcels beyond the 1st liter. The differences in the lead measured are usually driven by the differences in the types of pipe materials in contact with water during stagnation in the overall configuration of a service line that supplies a residence and the premise plumbing within the residence. The lead measured at the tap is regulated by the United States Environmental Protection Agency under the Lead and Copper Rule of 1991, which stipulates that the 90th percentile of lead concentrations should be below 15 µg/L. Recent revisions to the LCR introduced a 5th liter sample collection in addition to 1st liter sample for monitoring lead at residences with lead service lines (LSLs). However, there is limited information regarding the extent to which the 1st and 5th liter lead concentrations will differ. A systematic approach based on equilibrium solubility modelling can be used to accurately predict the lead in the 5th liter if the water stagnates within the LSL long enough to reach equilibrium. A national database was created with information on the 90th percentile 1st liter lead and key water chemistry variables from 434 very large public water systems in the United States in 2019. The solubility-based model was used to estimate dissolved lead concentrations in equilibrium with the lead…
abstract: Lead is a toxic heavy metal and legacy contaminant in drinking water that can be released from lead service lines and lead-containing premise plumbing. Lead concentrations in water are sensitive to changes in water chemistry. The extent of lead release is often driven by the solubility of the corrosion products formed on the interior of the pipes. Therefore, it is critical to advance our understanding of the extent of lead released from different lead-based plumbing materials at equilibrium and the ability to control lead when it exceeds the regulatory levels. Lead measured in the 1st liter of water collected from a tap can be significantly different from the lead measured in the water parcels beyond the 1st liter. The differences in the lead measured are usually driven by the differences in the types of pipe materials in contact with water during stagnation in the overall configuration of a service line that supplies a residence and the premise plumbing within the residence. The lead measured at the tap is regulated by the United States Environmental Protection Agency under the Lead and Copper Rule of 1991, which stipulates that the 90th percentile of lead concentrations should be below 15 µg/L. Recent revisions to the LCR introduced a 5th liter sample collection in addition to 1st liter sample for monitoring lead at residences with lead service lines (LSLs). However, there is limited information regarding the extent to which the 1st and 5th liter lead concentrations will differ. A systematic approach based on equilibrium solubility modelling can be used to accurately predict the lead in the 5th liter if the water stagnates within the LSL long enough to reach equilibrium. A national database was created with information on the 90th percentile 1st liter lead and key water chemistry variables from 434 very large public water systems in the United States in 2019. The solubility-based model was used to estimate dissolved lead concentrations in equilibrium with the lead…
author: Mishrra, Anushka
language: English (en)
keywords: 90th percentile lead, Advanced treated water, Blending, corrosion control, Lead service line, sodium silicate, Environmental Engineering
date published: 2022-08-15T07:00:00Z
date modified: 2026-07-24T06:13:49Z
provider: Washington University in St. Louis
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: Washington University in St. Louis

PropertyValue
property ID: DOI
value: 10.7936/k3xy-xy04