Modeling Drinking Water Lead Exposure from Premise Plumbing
Citation:
Burkhardt, J., R. Murray, H. Woo, AND J. Mason. Modeling Drinking Water Lead Exposure from Premise Plumbing. Presented at EWRI 2018, Minneapolis, MN, June 03 - 07, 2018.
Impact/Purpose:
Understanding how users in a home or building are impacted by usage patterns, plumbing configurations, or other factors is a vital part of quantifying their risk. This work sets out to highlight the modeling effort that seeks to provide that understanding. Exposure to drinking water contaminants, specifically lead, remains an important health concern. Modeling lead release within home plumbing systems includes quantifying the dissolution of lead into the water from all lead sources, and the transport of that lead through the pipes/appliances to the points of water use (e.g., faucets). An appropriate chemical reaction model, accurate mapping of plumbing materials/sizes/configurations within a plumbing system, and unique water demand patterns in the home must be incorporated in a modeling effort. Each water use event in the demand pattern drives flow in the system and moves varying amounts of water to each faucet or fixture. However, the lead content of water consumed at a faucet is impacted by both current and previous water uses within the system. A modeling effort was undertaken to understand the impacts of premise plumbing layout and demand patterns to help predict exposure risk. In this study, EPANET and EPANET-MSX were used to model lead dissolution in premise plumbing and were compared to data collected in a Home Plumbing System Simulator at the United States Environmental Protection Agency. Modifications to made EPANET and EPANET-MSX to account for stagnant flow conditions found in premise plumbing systems will be discussed. This work highlights the validation and parameterization effort. Additionally, a series of Monte Carlo simulations will be discussed to highlight the impact of various relevant parameters—specifically, the impact of lead service line length, number of users in the home, configuration and size of the home plumbing system and types of usage patterns present.
Description:
Exposure to drinking water contaminants, specifically lead, remains an important health concern. Modeling lead release within home plumbing systems includes quantifying the dissolution of lead into the water from all lead sources, and the transport of that lead through the pipes/appliances to the points of water use (e.g., faucets). An appropriate chemical reaction model, accurate mapping of plumbing materials/sizes/configurations within a plumbing system, and unique water demand patterns in the home must be incorporated in a modeling effort. Each water use event in the demand pattern drives flow in the system and moves varying amounts of water to each faucet or fixture. However, the lead content of water consumed at a faucet is impacted by both current and previous water uses within the system. A modeling effort was undertaken to understand the impacts of premise plumbing layout and demand patterns to help predict exposure risk. In this study, EPANET and EPANET-MSX were used to model lead dissolution in premise plumbing and were compared to data collected in a Home Plumbing System Simulator at the United States Environmental Protection Agency. Modifications to made EPANET and EPANET-MSX to account for stagnant flow conditions found in premise plumbing systems will be discussed. This work highlights the validation and parameterization effort. Additionally, a series of Monte Carlo simulations will be discussed to highlight the impact of various relevant parameters—specifically, the impact of lead service line length, number of users in the home, configuration and size of the home plumbing system and types of usage patterns present.