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Many public utilities that use chloramine as a secondary disinfectant have adopted an annual maintenance practice called chlorine-burn. Chlorine-burn is a practice whereby free chlorine is permitted to flow through the distribution network for two to eight weeks. The purpose of a...

During dichloramine decomposition, the relative importance of nitrogen and oxygen containing end-products from the reactive nitrogen species pathway is unknown.  At pH 9 with and without 10 μM total dimethylamine (TOTDMA) and 200, 400, or 800 μeq Cl2•L−1 initial dichloramine, nit...

Many factors, including microbiome structure and activity in the drinking water distribution system (DWDS), affect the colonization potential of opportunistic pathogens. The present study aims to describe the dynamics of active bacterial communities in DWDS and identify the facto...

Many public utilities that use chloramine as a secondary disinfectant have adopted an annual maintenance practice called chlorine-burn. Chlorine-burn is a practice whereby free chlorine is permitted to flow through the distribution network for two to eight weeks. The purpose of a...

The reaction mechanism for dichloramine decomposition has remained unresolved for several decades.  Previous studies have focused on the fate of the chloramine species, free ammonia, and nitrogen gas rather than the minor intermediates and decay products that comprise less t...

Finished water storage facilities are tanks or reservoirs used to store water that will undergo no further treatment to reduce microbial pathogens except residual disinfections. Storage tanks are vulnerable to contamination, and excess water retention time may cause depletion of ...

This report summarizes the results of infrastructure decontamination experiments performed at the WSTB.  These experiments focused on simulating contamination of drinking water distribution pipes with a commonly available insecticide formulation containing malathion.  M...

Finished water storage facilities are tanks or reservoirs used to store water that will undergo no further treatment to reduce microbial pathogens. Storage tanks are vulnerable to contamination and excess water retention time may cause depletion of disinfectant residual which cre...

Presentation will provide a summary of recently published manuscript:  Abulikemu, G., Mistry, J. H., Wahman, D. G., Alexander, M. T., Kennicutt, A. R., Bollman, J. D., and Pressman, J. G. (2023) Investigation of Chloramines, Disinfection By-products, and Nitrification in Chloram...

The lack of widely available methods for distinguishing and quantifying organic chloramines has raised concerns for maintaining effective disinfectant residuals in chloraminated drinking water distribution systems (CDWDSs). This study provided quantitative estimation of dichloram...

Plastic pollution is ubiquitous worldwide. Smaller pieces of plastic (<5 mm) denominated as microplastics (MPs) are of particular concern because they can be easily transported throughout the environment. As they travel, MPs can adsorb chemicals or nutrients, and develop a biofil...

This study represents an important first step towards using microelectrodes to (1) understand and provide direct measurement of oxidant microprofiles from the bulk water to the metal surface; (2) determine pipe wall reactivity using the directly measured concentrations profiles v...

Nitrite (NO2−) produced during nitrification episodes in chloraminated drinking water distribution systems (CDWDSs) is typically quantified using ion chromatography (IC) or colorimetric techniques.  NO2− can also be quantified using chemometric models (CMs) formulated using molar...

The chloramination of bromide containing waters results in the formation of the bromine containing haloamines: monobromamine, dibromamine, and bromochloramine (NHBrCl). Many studies have directly shown that bromamines are more reactive than chloramines in oxidation and substituti...

Periods of lowered to zero occupancy can be challenging for occupational building systems and may increase the risk of water system failures and other hazards for occupants. Water stagnation can lead to reduced water quality including presence of opportunistic pathogens (includin...

Finished water storage facilities are tanks or reservoirs used to store water that will undergo no further treatment to reduce microbial pathogens. Storage tanks are vulnerable to contamination, and excess water retention time may cause depletion of disinfectant residual which cr...

Finished water storage facilities are tanks or reservoirs used to store water that will undergo no further treatment to reduce microbial pathogens except residual disinfections. Storage tanks are vulnerable to contamination, and excess water retention time may cause depletion of ...

In this study, we investigated the efficacy of different treatment options on the microbial population and occurrence of these OPPPs along with phagocytic amoebae in a simulated home plumbing system (HPS). Water samples were collected from eight locations in the HPS on a weekly b...

Opportunistic premise plumbing pathogens (OPPPs) are frequently detected in the plumbing systems of large buildings. There are three major OPPPs such as Legionella pneumophila, three nontuberculous mycobacterial species (NTM) (e.g., Mycobacterium avium, M. intracellulare, and M. ...

EPA conducted a research study to understand how maintaining various drinking water distribution system disinfectant residual concentrations (affected by water age or operational practice) corresponded to the microbial communities (heterotrophic bacteria and Mycobacteria) found i...

This study investigated elemental surface coatings and multiple biofilm parameters across the depth of six pilot-scale aerated contactors treating groundwaters containing ammonia (NH3), iron (Fe), manganese (Mn), and arsenic (As). The biofilm parameters investigated were morpholo...

The mechanism for dichloramine decomposition has remained unresolved for over three decades, with previous studies focused on the fate of the chloramine species, free ammonia, and nitrogen gas rather than the relatively minor intermediates and decay products that comprise less th...

The use of ultraviolet (UV) lamps in water treatment is a promising alternative to conventional water disinfection techniques (e.g., chlorination and ozonation). UV disinfection inactivates a broad range of microorganisms without chemicals, thereby eliminating the problem of disi...

The use of ultraviolet (UV) lamps in water treatment is a promising alternative to conventional water disinfection techniques (e.g., chlorination and ozonation). UV disinfection inactivates a broad range of microorganisms without chemicals, thereby eliminating the problem of disi...

To evaluate natural organic matter (NOM) processing impacts on preformed monochloramine (PM) reactivity and as a first step in creating concentrated disinfection byproduct (DBP) mixtures from PM, a rational methodology was developed to proportionally scale PM NOM related demand i...