Modeling Water Age in Premise Plumbing Systems
Citation:
Burkhardt, J., H. Woo, J. Mason, W. Platten, AND R. Murray. Modeling Water Age in Premise Plumbing Systems. World Environmental & Water Resources Congress 2019, Pittsburgh, Pennsylvania, May 19 - 23, 2019.
Impact/Purpose:
The purpose of this work is understand how home or building plumbing impacts the age of the water found under normal usage conditions. Water age can provide a general indication of water quality, and this work highlights its use in assessing how various factors impact water age. This supports ongoing work in NRMRL, NERL and Office of Water, related to premise plumbing and associated research. No specific results are presented in this abstract.
Description:
Water quality in homes and buildings is impacted by a combination of the incoming water chemistry, characteristics of the unique plumbing system, and how the water is used. Modeling premise plumbing systems enables the examination of different aspects of hydraulics and water quality. Water stagnation in buildings is known to result in degraded water quality. Intermittent usage by water using appliances and fixtures in premise plumbing systems results in a range of stagnation periods in different parts of a building through time. Water age can provide general information that can be an indicator of changes in water chemistry, contamination release from the pipe wall, and growth of microbial communities. Models of water age can help determine the location of stagnant water within a system, and can help identify strategies to improve water quality by changing plumbing materials, configuration, or water usage patterns. In this study, EPANET was used to model water age in three different systems: a laboratory home plumbing system simulator and two actual homes. All water using appliances and fixtures are represented in each of the three systems, including showers, toilets, hot water heaters, dishwashers, washing machines, refrigerators, and faucets. A Python script was used to generate realistic intermittent demand patterns reflecting typical use for 1-4 residents, run EPANET, and analyze the resulting output. The impact of different factors on water age will be explored, specifically, how usage patterns affect the volume of water in a building at different water ages. Strategies for reducing water age and improving water quality will be addressed.