Project description:The lead contamination of drinking water in homes and buildings remains an important public health concern. In order to assess strategies to measure and reduce exposure to lead from drinking water, models are needed that incorporate the multiple factors affecting lead concentrations in premise plumbing systems (PPS). In this study, the use of EPANET, a commonly used hydraulic and water quality model for water distribution systems, was assessed for its ability to predict lead concentrations in PPS. The model was calibrated and validated against data collected from multiple experiments in the EPA's Home Plumbing Simulator that contained a lead service line and other lead sources. The EPANET's first-order saturation kinetics model was used to simulate the dissolution of lead in the lead service line. A version of EPANET was developed to include one-dimensional mass dispersion. Modeling results were compared to experimental data, and recommendations were made to improve the EPANET-based modeling framework for predicting lead concentrations in PPS.
| S-EPMC7898126 | biostudies-literature
Project description:Extreme Stagnation within Premise Plumbing
Project description:Tools used to predict hydraulics and water quality within premise plumbing systems have gained recent interest. An open-source Python-based tool-PPMtools-for modeling and analyzing premise plumbing systems with WNTR or EPANET is presented. A relative water age-the time water has spent in a home-study using three real-world single-family homes was used to demonstrate PPMtools. Results showed that increased use-more people or higher flow fixtures-led to a general decrease in relative water ages. However, even with more use, one user could still experience water for a drinking activity with a relative water age equal to, or longer than, the duration of the longest stagnant period (sleeping or absence from home). Simulations also showed that the general relative water ages increased if the homes were plumbed with larger diameter piping [19.1 mm (3/4 in.) versus 12.7 mm (1/2 in.)]. Hot water heaters were found to have the largest impact on relative water age. Smaller volume uses generally had more variability in relative water ages, while larger volume uses (e.g., showering) resulted in generally low relative water ages with less variability because larger uses fully replaced water in the home with water from the main. This study highlights the potential for using PPMtools to explore more complex water quality modeling within premise plumbing systems.