Stagnation in water supply systems as a factor in water quality degradation – an overview of the issue
DOI:
https://doi.org/10.17512/INSTAL.2026.03.02Keywords:
stagnation, water system, water quality, biofilm, building water managementAbstract
Stagnation in internal water systems is one of the key factors negatively affecting water quality for consumers. Under conditions of low flow and long residence time, a decrease in disinfectant levels, an increase in microorganism counts, and changes in the system's microbiome structure can be observed, along with an increased risk of metal release and deterioration of organoleptic properties (i.e., taste and odor). This article presents the mechanisms of water quality degradation caused by stagnation, typical locations of stagnant zones, and the role of temperature in shaping microbiological risk. The following section discusses contemporary design-related conditions, presents an example scenario of water quality degradation in a new building, and outlines the responsibilities of the designer and the facility manager. The importance of a risk-based approach and water system management programs is emphasized.
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Copyright (c) 2026 Karolina Herczyk, Anna Grobelak (Autor)
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