Monitoring Of Water Sources Research Articles

Determining Sources of Dissolved Organic Carbon and Disinfection Byproduct Precursors to the McKenzie River, Oregon

This study was conducted to determine the main sources of dissolved organic carbon (DOC) and disinfection byproduct (DBP) precursors to the McKenzie River, Oregon (USA). Water samples collected from the mainstem, tributaries, and reservoir outflows were analyzed for DOC concentration and DBP formation potentials (trihalomethanes [THMFPs] and haloacetic acids [HAAFPs]). In addition, optical properties (absorbance and fluorescence) of dissolved organic matter (DOM) were measured to provide insight into DOM composition and assess whether optical properties are useful proxies for DOC and DBP precursor concentrations. Optical properties indicative of composition suggest that DOM in the McKenzie River mainstem was primarily allochthonous--derived from soils and plant material in the upstream watershed. Downstream tributaries had higher DOC concentrations than mainstem sites (1.6 +/- 0.4 vs. 0.7 +/- 0.3 mg L(-1)) but comprised < 5% ofmainstem flows and had minimal effect on overall DBP precursor loads. Water exiting two large upstream reservoirs also had higher DOC concentrations than the mainstem site upstream of the reservoirs, but optical data did not support in situ algal production as a source of the added DOC during the study. Results suggest that the first major rain event in the fall contributes DOM with high DBP precursor content. Although there was interference in the absorbance spectra in downstream tributary samples, fluorescence data were strongly correlated to DOC concentration (R2 = 0.98), THMFP (R2 = 0.98), and HAAFP (R2 = 0.96). These results highlight the value of using optical measurements for identifying the concentration and sources of DBP precursors in watersheds, which will help drinking water utilities improve source water monitoring and management programs.

Mapping Ground Water Rule Requirements: Consumer Confidence Report, Public Notification, and Special Notice

This is the fifth and final column in a series developed by the U.S. Environmental Protection Agency (USEPA), Office of Ground Water and Drinking Water, summarizing key components of the Ground Water Rule (GWR). The previous four columns in the series focused on source water monitoring, compliance monitoring, sanitary surveys, and corrective action. This final column discusses GWR requirements regarding the Public Notification (PN) Rule, Consumer Confidence Report (CCR) Rule, and Special Notice.

Mapping Ground Water Rule Requirements: Sanitary Survey and Corrective Action

This is the fourth of five columns developed by the U.S. Environmental Protection Agency (USEPA), Office of Ground Water and Drinking Water, summarizing key components of the Ground Water Rule (GWR). Two of the four GWR requirements, source water and compliance monitoring, were discussed in Opflow's July and August 2010 issues, respectively. Source water monitoring, which includes triggered, additional, and assessment monitoring, is required for systems not providing 4‐log treatment. Compliance monitoring addresses how operators document 4‐log treatment of viruses through monitoring and maintaining a state‐determined minimum disinfectant residual. This column addresses sanitary surveys and corrective action.

Mapping Ground Water Rule Requirements: Source Water Compliance and Assessment Monitoring

This is the third of five columns developed by the U.S. Environmental Protection Agency (USEPA), summarizing key components of the Ground Water Rule (GWR). This column discusses the components of compliance monitoring and assessment source water monitoring. Compliance monitoring is required for groundwater systems (GWSs) that have notified the state that they reliably provide 4‐log treatment of viruses, and as a form of corrective action or in lieu of triggered source water monitoring. Assessment source water monitoring is a tool available to a state that suspects a system's groundwater source might be vulnerable to fecal contamination.

Mapping Ground Water Rule Requirements: Triggered and Additional Source Water Monitoring

This is the second of five columns developed by the U.S. Environmental Protection Agency (USEPA), summarizing key components of the Ground Water Rule (GWR). This column details source water monitoring, focusing on triggered and additional source water monitoring. These apply to groundwater systems (GWSs) that don't reliably provide 4‐log virus treatment, which includes inactivation or removal or a state‐approved combination of these technologies before or at the first customer. These systems may have to conduct source water monitoring to comply with the GWR if a total coliform‐positive (TC+) sample is collected in their distribution system.

Probabilistic design of a riverine early warning source water monitoring systemA paper submitted to the Journal of Environmental Engineering and Science.

Source water protection involves safeguarding water supplies from contamination and depletion. Despite best efforts, spills cannot always be prevented from entering a source water body. However, many spills can be prevented from entering a drinking water treatment plant if an early warning source water monitoring station is used. These stations provide downstream water utilities with advanced notification of spills so the utilities have time to implement their responses. This paper addresses the design of an early warning monitoring station for a riverine source of drinking water. Riverine water supplies face many threats related to accidental spills, which are inherently uncertain in nature. Therefore, designing a monitoring station for the detection of these events requires a probabilistic modelling approach. The design objectives include maximizing the probabilities of detection and of having a threshold amount of warning time. The methodology is applied to a water supply intake on the Grand River in southern Ontario.

Ground Water Rule Compliance

This article discusses the basic requirements for compliance to the Ground Water Rule beginning December 1, 2009. Topics covered include: sanitary surveys to review and evaluate eight elements including source, treatment, distribution system, finished water storage, pumps, pump facilities, and controls, monitoring, reporting, and data verification, system management and operations, and operator compliance with state requirements; source water monitoring; analytical methods for fecal indicators; corrective action requirements; compliance monitoring; and, compliance deadlines. A list of guidance manuals to assist groundwater systems and state primacy agencies in compliance with the Ground Water Rule is provided.

Occurrence and co‐occurrence of perchlorate and nitrate in California drinking water sources

Perchlorate, a chemical that affects the ability of the thyroid to absorb iodide, has been detected in many drinking water sources, mainly groundwaters. Perchlorate enters groundwater via permeation from surface water; other contaminants can enter groundwater in the same fashion. The purpose of this study was to determine the overall distribution of perchlorate and nitrate in California drinking water sources and the co‐occurrence (if any) of nitrate and perchlorate. The study used the California Department of Health Services Division of Drinking Water and Environmental Monitoring database of all source water monitoring results, including those for nitrate and perchlorate. Data for nitrate (1994–2003) and perchlorate (1997–2003) were queried, and results (including nondetects) were averaged. A similar query was performed for all results above the reporting limit. All sources with positive results for perchlorate were queried for nitrate results. Nitrate results collected within 180 days of a positive perchlorate result were used. Results indicated that the mean perchlorate level in California drinking water sources was 3.6 μg/L, and the mean nitrate level was 21,000 μg/L. Among sources with positive perchlorate results, the mean perchlorate result was 12 μg/L, and the mean nitrate result was 39,000 μg/L for nitrate. A weak but statistically significant correlation was found between the concentrations of perchlorate and nitrate (R2 = 0.31, p &lt; 0.001).

The Ground Water Rule: The First Federal Drinking Water Regulation to Require Microbial Source Water Monitoring

he nation’s ground water is an indispensable natural resource. One of many uses of ground water sources is to supply drinking water to millions of people across the country. Ensuring that Americans obtain safe drinking water is a key objective of the federal drinking water program. In 2006, the scope of the U.S. EPA drinking water program was expanded to include the Ground Water Rule (GWR)—a national primary drinking water regulation developed to address public health concerns related to fecal contamination in ground water systems (GWSs). The presence of fecal contamination in ground water sources indicates that the source may contain infectious viral or bacterial pathogens. Ingestion of these pathogens may cause adverse human health conditions. The Centers for Disease Control and Prevention’s (CDC) 1991 to 2000 water borne disease outbreak information provides evidence of health concerns related to contaminated ground water sources. The GWR is the first federal drinking water regulation in the United States that requires GWSs not under the influence of surface water to monitor their ground water sources for fecal indicators. In addition to source water monitoring, the rule requires states to perform periodic sanitary surveys of GWSs to inspect for significant deficiencies that may lead to contamination. The GWR requires systems that have an indication of fecal contamination or have detected significant deficiencies to take corrective action to ensure that the drinking water from ground water sources is safe for human consumption.

Source water monitoring pushes Seattle to the forefront

This report discusses Seattle Public Utilities' (SPU) use of Defined Substrate Technology (DST) for better detection of bacteria when monitoring its source water and distribution system water quality.

Response characteristics of an aquatic biomonitor used for rapid toxicity detection.

The response characteristics of an aquatic biomonitor that detects toxicity by monitoring changes in bluegill (Lepomis macrochirus Rafinesque) ventilatory and movement patterns were evaluated in single chemical laboratory studies at concentrations near the 96-h LC(50) concentration and at the EILATox-Oregon Workshop in sequential tests of multiple unknown samples. Baseline data collected prior to exposure allows each fish to serve as its own control. When at least 70% of exposed fish exhibit ventilatory or movement parameters significantly different from baseline observations, a group alarm is declared. In the laboratory studies, the aquatic biomonitor responded to the majority of chemicals at the 96-h lc(50) within an hour or less, although substantially higher response times were found for malathion and pentachlorophenol. Workshop tests of single chemical concentrations presented as blind samples were consistent with the laboratory test results. There were no alarms under control conditions in any test. Although data are limited, the aquatic biomonitor appears to respond more rapidly to chemicals causing membrane irritation, narcosis or polar narcosis than to acetylcholinesterase inhibitors or oxidative phosphorylation uncouplers. All four monitored parameters (ventilatory rate, cough rate, ventilatory depth and movement) contributed to identification of first alarms at acutely toxic levels. Understanding these response patterns can be useful in data interpretation for biomonitor applications such as surface water monitoring for watershed protection, wastewater treatment plant effluent monitoring or source water monitoring for drinking water protection.

QUALITY OF SOURCE WATER IN A RURAL AREA OF GUATEMALA

Over 75% of the world's.population lives in underdeveloped areas without access to safe drinking water. Water sources are scarce and frequently heavily contaminated. This has been linked to severe health problems, including diarrheal disease which causes an estimated 2.2 million deaths per year. In Latin America, it is estimated that 40% of households receive water inadequately treated or not treated at all. Water treatment to assure safe drinking water is not routinely performed in rural areas of Guatemala although municipal governments are compelled by law to disinfect water. Even though local villagers consider their water to be clean, it is generally thought by the scientific community that water in rural areas is unsafe. We studied the quality of the water sources of ten rural communities of San Juan Sacatepequez, located 30 kilometers from Guatemala City. The sources selected were available most of the year and frequently used. Initial water samples were collected during 1999 from a cross-sectional pilot study. These samples were analyzed for water quality for presence of bacteria, parasites and viruses. The samples screened for bacteria were processed using a modification of the most probable number method and tested with Colilert Quanti-tray® to quantify total coliforms and Escherichia coli. Water samples were collected using the USEPA Information Collection Rule (ICR) method for concentration and detection of protozoan parasites and viruses and measured by immunofluorescent assay (IFA) and cell culture assays, respectively. Additionally, the concentrates were subjected to community DNA extraction followed by PCR amplification and sequencing to identify the presence of Cyclospora cayetanensis and Microsporidia. Of a total of 35 water samples screened for bacteria, 25 (77%) showed presence of E. coli with an average contamination level of 2 x 103 UFC/100 ml. Ten of the most contaminated sources, with the highest levels of total coliforms and E. coli were examined for parasites and viruses. Of the 10 sample sites, seven were confirmed positive for Giardia lamblia and three for Cryptosporidium parvum. Enteroviruses were found in three out of the 10 sample sites. Six samples showed positive amplification for Microsporidial DNA and three were confirmed for C. cayetanensis. The most effective microbiological monitoring of water sources and drinking water in general is the determination of the presence of bacteria, especially E. coli, but water might contain a range of pathogens which would represent different risks. The non-bacterial pathogens found are the first documented reports of parasite and viruses found in drinking water in the country. Giardia and Cryptosporidium are not sensitive to regular disinfection by chlorine, its finding draws attention to the need of identifying other intervention strategies for their elimination. The results of this study demonstrate high levels of bacterial, parasitic and viral contamination on water sources in these rural communities. Water sources in these areas consist of reservoirs fed by springs or wells and available water is frequently contaminated by both human and animal feces.

Natural Protection of Spring and Well Drinking Water Against Surface Microbial Contamination. II. Indicators and Monitoring. Parameters for Parasites

Recent outbreaks of cryptosporidiosis and reports of other newly described para-sitic diseases associated with drinking water transmission prompted a reevaluation of source water monitoring criteria for public health protection. The field of microbial indicators was reviewed and each candidate sentinel evaluated in terms of its sensitivity, specificity, and technical feasibility. In addition, a clear distinction was made between source water monitoring and monitoring in the distribution system. Of all potential candidate microbial sentinels, Escherichia coli is deemed the most efficacious for public health protection. Based on a conservative estimate of its half-life in groundwater for 8 d. it is recommended that at least two samples be obtained during this half-life. In addition to E. coli, two water quality indicator sentinels, which are not necessarily direct public health threats, should also be monitored at the same frequency. These are the total coliform group and the enterococci. If E. coli is present in any source water sample, the borehole and any directly connected borehole should be embargoed. If either total coliforms or enterococci are detected, only that individual borehole should be taken off line and not used until the situation is remediated and the cause of the fecal contamination eliminated. Clostridium perfrigens spores serve as a useful long-lived indicator. However, their perseverance in a sample should not be considered a direct public health threat because spores may far outlive pathogens. As a parasite indicator, C. perfringens should have the same importance as a positive colifom or enterococcus analysis. Coliphages do not yet fulfill enough of the criteria to be routinely employed. Biological monitoring should be coupled with physicochemical monitoring to establish a long-term history of the source. Because all natural waters vary in the amounts of heterotrophic plate count bacteria, test methods should be employed that are refractory to them. A combination of rigorous source protection plus extraordinary source monitoring serve as sufficient multiple barriers for parasite protection.