Although recent studies suggest contamination by bacteria and nitrate in private drinking water systems is of increasing concern, data describing contaminants associated with the corrosion of onsite plumbing are scarce. This study reports on the analysis of 2,146 samples submitted by private system homeowners. Almost 20% of first draw samples submitted contained lead concentrations above the United States Environmental Protection Agency action level of 15 μg/L, suggesting that corrosion may be a significant public health problem. Correlations between lead, copper, and zinc suggested brass components as a likely lead source, and dug/bored wells had significantly higher lead concentrations as compared to drilled wells. A random subset of samples selected to quantify particulate lead indicated that, on average, 47% of lead in the first draws was in the particulate form, although the occurrence was highly variable. While flushing the tap reduced lead below 15 μg/L for most systems, some systems experienced an increase, perhaps attributable to particulate lead or lead-bearing components upstream of the faucet (e.g., valves, pumps). Results suggest that without including a focus on private as well as municipal systems it will be very difficult to meet the existing national public health goal to eliminate elevated blood lead levels in children.

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Although extensive literature documents corrosion in municipal water systems, only minimal data is available describing corrosion in private water systems (e.g., wells), which serve as a primary source of drinking water for approximately 47 million Americans. This study developed a profiling technique specifically tailored to evaluate lead release in these systems. When applied in an intensive field study of 15 private systems, three patterns of lead release were documented: no elevated lead or lead elevated in the first draw only (Type I), erratic spikes of particulate lead (Type II), and sustained detectable lead concentrations (Type III). While flushing protocols as short as 15-30 s may be sufficient to reduce lead concentrations below 15 μg/L for Types I and III exposure, flushing may not be an appropriate remediation strategy for Type II exposure. In addition, the sustained detectable lead concentrations observed with Type III exposure likely result from corrosion of components within the well and therefore cannot be reduced with increased flushing. As profiling techniques are labor- and sample-intensive, we discuss recommendations for simpler sampling schemes for initial private system surveys aimed at quantifying lead and protecting public health.

Over one million households rely on private water supplies (e.g. well, spring, cistern) in the Commonwealth of Virginia, USA. The present study tested 538 private wells and springs in 20 Virginia counties for total coliforms (TCs) and Escherichia coli along with a suite of chemical contaminants. A logistic regression analysis was used to investigate potential correlations between TC contamination and chemical parameters (e.g. NO3(-), turbidity), as well as homeowner-provided survey data describing system characteristics and perceived water quality. Of the 538 samples collected, 41% (n = 221) were positive for TCs and 10% (n = 53) for E. coli. Chemical parameters were not statistically predictive of microbial contamination. Well depth, water treatment, and farm location proximate to the water supply were factors in a regression model that predicted presence/absence of TCs with 74% accuracy. Microbial and chemical source tracking techniques (Bacteroides gene Bac32F and HF183 detection via polymerase chain reaction and optical brightener detection via fluorometry) identified four samples as likely contaminated with human wastewater.

Significant challenges in the provision of safe drinking water and appropriate, effective sanitation remain in the United States, particularly among communities with few financial resources and/or situated in challenging terrain. Though previous formal research is limited, anecdotal reports suggest that some households in Appalachia may rely on untreated, unregulated roadside "springs" as a primary source of potable water. This effort monitored the water quality at twenty-one of these springs in Central Appalachia and identified potential motivations for this behavior through volunteer surveys in order to better define community challenges and to establish communication for future outreach. The majority (>80%) of spring samples collected were positive for E. coli, indicating a potential risk of exposure to waterborne pathogens; measured concentrations of metals and nutrients were generally in accordance with USEPA recommendations for drinking water. Survey respondents generally had a piped source of in-home water available yet primarily collected the water due to "taste" and "quality/health" and used it directly for drinking. Multiple respondents included extra written information indicating that they either did not trust their in-home water source or considered it unreliable. Collectively these results suggest that these roadside springs do serve as a regular source of household water for some communities though they generally do not meet federal drinking water standards. Future efforts are encouraged to work with local municipal water authorities to rebuild community trust and/or to determine whether on-site treatment at these springs is practicable.

Section 9 of NSF International/American National Standards Institute (NSF/ANSI) Standard 61 evaluates lead‐leaching potential from end‐point devices to protect consumer health. However, because the NSF/ANSI protocol stipulates a high pH and alkalinity characteristic of municipal waters, it is not likely generalizable to the aggressive water chemistries more consistent with water quality observed in private systems. To assess lead release from components installed in private systems, this study exposed brass and galvanized steel that meet lead‐free requirements to more aggressive waters. As expected, lead leaching from C36000 brass increased with decreasing pH and alkalinity, but post‐2014 lead‐free brass released nondetectable concentrations when exposed to aggressive conditions. However, post‐2014 lead‐free galvanized steel may still release significant lead in aggressive waters as a result of the sorption of lead to plumbing. Although new lead‐free brass products are more protective of communities dependent on private systems, elevated lead from both legacy materials and galvanized steel remains an issue for systems without corrosion control.

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Elevated concentrations of fecal indicator bacteria in receiving waters during wet-weather flows are a considerable public health concern that is likely to be exacerbated by future climate change and urbanization. Knowledge of factors driving the fate and transport of fecal indicator bacteria in stormwater is limited, and even less is known about molecular fecal indicators, which may eventually supplant traditional culturable indicators. In this study, concentrations and loading rates of both culturable and molecular fecal indicators were quantified throughout six storm events in an instrumented inland urban stream. While both concentrations and loading rates of each fecal indicator increased rapidly during the rising limb of the storm hydrographs, it is the loading rates rather than instantaneous concentrations that provide a better estimate of transport through the stream during the entire storm. Concentrations of general fecal indicators (both culturable and molecular) correlated most highly with each other during storm events but not with the human-associated HF183 Bacteroides marker. Event loads of general fecal indicators most strongly correlated with total runoff volume, maximum discharge, and maximum turbidity, while event loads of HF183 most strongly correlated with the time to peak flow in a hydrograph. These observations suggest that collection of multiple samples during a storm event is critical for accurate predictions of fecal indicator loading rates and total loads during wet-weather flows, which are required for effective watershed management. In addition, existing predictive models based on general fecal indicators may not be sufficient to predict source-specific genetic markers of fecal contamination.