Chlorinous flavors at the tap are the leading cause of customers' complaints and dissatisfaction with drinking water. To characterize consumer perception and acceptance to chlorinous tastes, extensive taste testing was performed with both trained panelists and average consumers. Taste testing with trained panelists showed that chlorine perception is underestimated by disinfectant flavor thresholds reported in the literature. However, trained panelists significantly overestimate the average consumer's ability to perceive chlorine. In addition, consumer perception seems to be influenced by the chlorination practices of the country they live in. Among water quality characteristics that may influence chlorine perception, temperature was not found to induce any significant change. The influence of total dissolved solids (TDS) on chlorine perception remains unclear and, as reported elsewhere, background tastes such as musty, may significantly impact chlorine threshold.

Considering this rapid growth in the purchasing of bottled water and home filtration devices, utilities are increasingly concerned about consumer dissatisfaction with tap water quality. This project aimed to characterize public perceptions of chlorinous flavors in drinking water, and how these impact customers' choices with respect to consumption of tap water alternatives. On-site taste tests at seven water utilities with 30 to 40 panelists at each site, were conducted using a forced-choice triangle test method (ASTM method E679-91) to measure public sensitivity to chlorine and chloramine in drinking water. The chlor(am)ine concentration increased from set to set. The best-estimate sensitivity limit for each panelist was the geometric mean of that concentration at which the last miss occurred and the next (adjacent) higher concentration. The measured sensitivity limit of average American populations to free chlorine (159 persons tested) and chloramine (93 persons tested) in tap water were 0.8 and 3.7 mg/L Cl2, respectively. These thresholds are much higher than those previously reported in the literature using trained FPA panels. No significant differences were observed between tap water users and users of tap water alternatives or between the various markets tested with respect to average sensitivity, though individual sensitivity varied widely.

Stainless steels are corrosion‐resistant, but to take full advantage of their corrosion‐resistant properties, stainless steel piping and components must be properly specified, installed, and operated. The recommendations included in this article are intended to arm engineers and operators with a screening‐level tool for avoiding misapplication. To properly select the right grade of stainless steel for the various environmental conditions existing in different areas of the process, equipment, piping, and conveyance systems must be defined, including chlorides, pH, free chlorine in solution, bacteria, and temperature. Considering the environments that occur during idle, startup, normal operations, and shutdown conditions within treatment and conveyance facilities is also important. Once the stainless steel is specified and manufactured, proper care over its shipping, installation, and operation must be taken to protect the integrity of the materials to minimize corrosion.

The use and selection of microbial surrogates to validate ultraviolet (UV) reactor performance remain a challenge. Proper interpretation of bioassay results requires an appreciation of the relative UV dose–response of the surrogate and target organisms and the limitations surrogates impose. The aim of this study was to improve the understanding of MS2 coliphage's use as a bioassay surrogate for the waterborne pathogen Cryptosporidium parvum. Side‐by‐side MS2 and Cryptosporidium bioassays were performed to directly link MS2 and Cryptosporidium inactivation. At a flow rate of 757 L/min (200 gpm), the low‐pressure, high‐output UV reactor provided > 4.7‐log Cryptosporidium inactivation at an MS2 equivalent dose of 45 mJ/cm2. Although these data support the use of MS2 as a test organism to validate UV reactor performance, MS2 is a very conservative surrogate for Cryptosporidium. Use of a test organism with a more comparable UV dose–response would allow validation of much higher levels of log inactivation.

Customers are sensitive to the flavour of water. Customers evaluate drinking water based on their expectations, on experiences with their usual drinking water and on experiences with alternative waters. The Philadelphia Water Department provides one example of success in developing a better understanding of customer perceptions and attitudes about tap water taste and odour. Philadelphia found that customers do communicate in ways that water utilities can understand. Water utilities can enhance that communication and collect useful data. In addition, water utilities can characterise their tap water flavour, track it for changes and correlate changes to customer complaints.