Contaminant intrusion in water distribution systems: An ingress model

摘要

In a water distribution system, low or negative pressure may occur under normal operation and may lead to contaminant intrusion. To assess the risk associated with contaminant intrusion, exposure assessment is required. To obtain a more accurate intrusion exposure assessment, the effects of the surrounding soil on the intrusion rate must be considered. This article proposes a model that would provide a more realistic estimation of intrusion rate. A two-level factorial design was used to screen the effect of contributing factors in contaminant intrusion. The Buckingham π theorem was applied to group the influential factors into a set of dimensionless π parameters. The relationship among the π parameters was obtained by using the numerical data generated by a two-dimensional finite element model for flow in a saturated zone surrounding a pipe. A regression analysis was then applied to find the best fit for the data.