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1.
The goals of environmental legislation and associated regulations are to protect public health, natural resources, and ecosystems. In this context, monitoring programs should provide timely and relevant information so that the regulatory community can implement legislation in a cost-effective and efficient manner. The Safe Drinking Water Act (SDWA) of 1974 attempts to ensure that public water systems (PWSs) supply safe water to its consumers. As is the case with many other federal environmental statutes, SDWA monitoring has been implemented in relatively uniform fashion across the United States. In this three part series, spatial and temporal patterns in water quality data are utilized to develop, compare, and evaluate the economic performance of alternative place-based monitoring approaches to current monitoring practice. Part II: Several factors affect the performance of monitoring strategies, including: measurable objectives, required precision in estimates, acceptable confidence levels of such estimates, available budget for sampling. In this paper, we develop place-based monitoring strategies based on extensive analysis of available historical water quality data (1960-1994) of 19 Iowa community water systems. These systems supply potable water to over 350,000 people. In the context of drinking water, the objective is to protect public health by utilizing monitoring resources to characterize contaminants that are detectable, and are close to exceeding health standards. A place-based monitoring strategy was developed in which contaminants were selected based on their historical occurrence, rather than their appearance on the SDWA contaminant list. In a subset of the water systems, the temporal frequency of monitoring for one ubiquitous contaminant, nitrate, was tailored to patterns in its historical occurrence and concentration. Three sampling allocation models (linear, quadratic, and cubic) based on historic patterns in peak occurrence were developed and evaluated. Random and fixed-interval sampling strategies within the context of such models were also developed and evaluated. Strategies were configured to incorporate a variety of options for frequency and number of samples (depending on budget and the desired precision in estimate of peak concentrations).  相似文献   

2.
The goals of environmental legislation and associated regulations are to protect public health, natural resources, and ecosystems. In this context, monitoring programs should provide timely and relevant information so that the regulatory community can implement legislation in a cost-effective and efficient manner. The Safe Drinking Water Act (SDWA) of 1974 attempts to ensure that public water systems (PWSs) supply safe water to its consumers. As is the case with many other federal environmental statutes, SDWA monitoring has been implemented in relatively uniform fashion across the USA. In this three part series, we present over 30 years of evidence to demonstrate unique patterns in water quality contaminants over space and time, develop alternative place-based monitoring approaches that exploit such patterns, and evaluate the economic performance of such approaches to current monitoring practice. Part III: Place-based (PBA) and current SDWA monitoring approaches were implemented on test datasets (1995-2001) from 19 water systems and evaluated based on the following criteria: percent of total detections, percent detections above threshold values (e.g. 20, 50, 90% of MCL), and cost. The PBA outperformed the current SDWA monitoring requirements in terms of total detections, missed only a small proportion of detections below the MCL, and captured all detections above 50% of the MCL. Essentially the same information obtained from current compliance monitoring requirements can be gained at approximately one-eighth the cost by implementing the PBA. Temporal sampling strategies were implemented on test datasets (1995-2001) from four water systems and evaluated by the following criteria: parameter estimation, percent deviation from "true" 90th, 95th, and 99th percentiles, and number of samples versus accuracy of the estimate. Non event-based (NEB) strategies were superior in estimating percentiles 1-50, but underestimated the higher percentiles. Event-based strategies were superior in estimating 95th and 99th percentiles, and required significantly fewer samples (than NEB strategies) to estimate the "true" 95th and 99th percentiles. Incorporation of place-based information significantly improves the performance of monitoring and temporal sampling strategies in the context of surface-influenced water systems in the state of Iowa. Application of similar methods to other areas and types of water systems would likely produce similar results. Compared to current SDWA monitoring, the place based approach allows for cost-effective, enhanced characterization of local contaminants of concern.  相似文献   

3.
Stormwater is one of the last major untapped urban water resources that can be exploited as an alternative water source in Australia. The information in the current Australian Guidelines for Water Recycling relating to stormwater harvesting and reuse only emphasises on a limited number of stormwater quality parameters. In order to supply stormwater as a source for higher value end-uses, a more comprehensive assessment on the potential public health risks has to be undertaken. Owing to the stochastic variations in rainfall, catchment hydrology and also the types of non-point pollution sources that can provide contaminants relating to different anthropogenic activities and catchment land uses, the characterisation of public health risks in stormwater is complex, tedious and not always possible through the conventional detection and analytical methods. In this study, a holistic approach was undertaken to assess the potential public health risks in urban stormwater samples from a medium-density residential catchment. A combined chemical–toxicological assessment was used to characterise the potential health risks arising from chemical contaminants, while a combination of standard culture methods and quantitative polymerase chain reaction (qPCR) methods was used for detection and quantification of faecal indicator bacteria (FIB) and pathogens in urban stormwater. Results showed that the concentration of chemical contaminants and associated toxicity were relatively low when benchmarked against other alternative water sources such as recycled wastewater. However, the concentrations of heavy metals particularly cadmium and lead have exceeded the Australian guideline values, indicating potential public health risks. Also, high numbers of FIB were detected in urban stormwater samples obtained from wet weather events. In addition, qPCR detection of human-related pathogens suggested there are frequent sewage ingressions into the urban stormwater runoff during wet weather events. Further water quality monitoring study will be conducted at different contrasting urban catchments in order to undertake a more comprehensive public health risk assessment for urban stormwater.  相似文献   

4.
The Clean Water Act (CWA) has regulated discharges of contaminants since 1972. However, evaluations of the CWA's effectiveness at improving regional water quality are lacking, primarily because integration of monitoring data from multiple dischargers to assess cumulative effects is not required. A rare opportunity exists to assess CWA effectiveness by integrating mass emissions data from all major sources of contaminants to the Southern California Bight from 1971 to 2000. While the coastal population grew by 56% and total effluent volume increased 31% since 1971, mass emissions of nearly all constituents decreased since passage of the CWA, most by greater than 65%. Publicly owned treatment works were the dominant point source of many contaminants, but also accounted for the greatest reductions in pollutant discharge since 1971. As point source treatment has improved, the relative contribution of non-point sources, such as storm water runoff has increased. Despite the increased importance of storm water discharges, regional monitoring and data compilation of this source is lacking, making it difficult to accurately assess trends in non-point source discharge.  相似文献   

5.
The European Water Framework Directive (WFD) is the overall driver for this environmental study and currently requires the identification of patterns and sources of pollution (monitoring) to support objective ecological sound decision making and specific measures to enhance river water quality (modelling). The purpose of this paper is to demonstrate in a case study the interrelationship between (1) hydrologic and water quality monitoring data for river basin characterization and (2) modelling applications to assess resources management alternatives. The study deals with monitoring assessment and modelling of river water quality data of the main stem Saale River and its principal tributaries. For a period of 6 years the data, which was sampled by Environmental Agencies of the German states of Thuringia, Saxony and Saxony-Anhalt, was investigated to assess sources and indicators of pollution. In addition to the assessment a modelling exercise of the routing of different pollutants was carried out in the lower part of the test basin. The modelling is a tool to facilitate the evaluation of alternative measures to reduce contaminant loadings and improve ecological status of a water body as required by WFD. The transport of suspended solids, salts and heavy metals was modelled along a selected Saale reach under strong anthropogenic influence in terms of contaminants and river morphology between the city of Halle and the confluence with the Elbe River. The simulations were carried out with the model WASP5 which is a dynamic flood-routing and water quality model package developed by the US Environmental Protection Agency.  相似文献   

6.
The U.S. National Environmental Policy Act (NEPA) of 1969 heralded in an era of more robust attention to environmental impacts resulting from larger scale federal projects. The number of other countries that have adopted NEPA's framework is evidence of the appeal of this type of environmental legislation. Mandates to review environmental impacts, identify alternatives, and provide mitigation plans before commencement of the project are at the heart of NEPA. Such project reviews have resulted in the development of a vast number of reports and large volumes of project-specific data that potentially can be used to better understand the components and processes of the natural environment and provide guidance for improved and efficient environmental protection. However, the environmental assessment (EA) or the more robust and intensive environmental impact statement (EIS) that are required for most major projects more frequently than not are developed to satisfy the procedural aspects of the NEPA legislation while they fail to provide the needed guidance for improved decision-making. While NEPA legislation recommends monitoring of project activities, this activity is not mandated, and in those situations where it has been incorporated, the monitoring showed that the EIS was inaccurate in direction and/or magnitude of the impact. Many reviews of NEPA have suggested that monitoring all project phases, from the design through the decommissioning, should be incorporated. Information gathered though a well-developed monitoring program can be managed in databases and benefit not only the specific project but would provide guidance how to better design and implement future activities designed to protect and enhance the natural environment.  相似文献   

7.
Water quality of rivers, natural lakes, and reservoirs in developing countries is being degraded because of the contaminated inflows. There is a serious need for appropriate water quality monitoring for future planning and management of clean water resources. Quality of water in Rawal Lake Pakistan has been investigated in this paper. Flows from the upstream of Rawal Lake and its surrounding villages are highly polluted. Lake water quality parameters like pH, turbidity, alkalinity, calcium, nitrite, sulfate, biological oxygen dissolved, dissolved oxygen, chloride, total dissolved solids (TDS), and coliforms were investigated. Samples of water from different locations of Korang River were collected and tested. Most of the data was collected by field sampling and field visits. However, long-term information was taken from different departments. Statistical parameters (standard deviation, maximum, minimum, mean, mode, kurtosis, skew, and Euclidean distance) of variables were determined. A distinct parameter based on the difference of the maximum value the variable and maximum allowable value of that variable defined by World Health Organization was used for analysis. Grouping and clustering of elements was made on the basis of this parameter. Trend of increasing or decreasing of values of variables over a long time was also taken into account for grouping the variables. It was concluded that the concentration of seven contaminants was higher as compared to the permissible limits under environmental standards. These variables need immediate attention. The environmentally bad conditions of Rawal Lake can only be rectified by appropriate lake environmental supervision, watershed management, and implementation of environmental legislation.  相似文献   

8.
This study identifies and quantifies the spatial variations of metal contamination in water, sediment and biota: the common cockle (Cerastoderma edule) and the Mermaid’s glove sponge (Haliclona oculata), within a heavily anthropogenically impacted semi-enclosed estuarine–coastal area with a low ability to disperse and flush contaminants (Poole Harbour, UK). The results showed that metal contamination was detected in all environmental compartments. Water was polluted with As, and Hg sediment metals were mostly within “the possible effect range” in which adverse effects occasionally occurs. Cockles had considerable concentrations of Ni, Ag and Hg in areas close to pollution sources, and sponges accumulate Cu and Zn with very high magnitude. A systematic monitoring approach that includes biological monitoring techniques, which covers all embayments, is needed, and an integrated management of the semi-enclosed coastal zones should be based on the overall hydrological characteristics of these sensitive areas and their ability to self‐restore which is different than open coastal zones.  相似文献   

9.
State water quality agencies are custodians of water quality management programs under the Clean Water Act of which the protection and restoration of biological integrity in surface waters is an integral goal. However, an inappropriate reliance on chemical/physical stressor and exposure data or administrative indicators in place of the direct measurement of ecological response has led to an incomplete foundation for water resource management. As point sources have declined in significance, the consequences of this flawed foundation for dealing with the major limitations to biological integrity (nonpoint sources, habitat degradation) have become more apparent. The use of biocriteria in Ohio, for example, resulted in the identification of 50% more impairment than a water chemistry approach alone and other inconsistencies of a flawed monitoring foundation are illustrated in the national 305(b) report statistics on waters monitored, aquatic life use attainment, and habitat degradation. Biological criteria (biocriteria) incorporates the broader concept of water resource integrity to supplement the roles of chemical and toxicological approaches and reduces the likelihood of making overly optimistic estimates of aquatic life condition. A carefully conceived ambient monitoring approach comprised of biological, chemical, and physical measures ensures all relevant stressors to water resource integrity are identified and that the efficacy of administrative actions can be directly measured with environmental results. New multimetric indices, such as the IBI, ICI, and BIBI represent a significant advancement in aquatic resource characterization that have allowed the inclusion of biological information into many States water quality management programs. Ohio adopted numerical biocriteria in the Ohio water quality standards regulations in May 1990 and, through multiple aquatic life uses that reflect a continuum of biological condition, represents a tiered approach to water resource management. Biocriteria provide the impetus and opportunity to recognize and account for natural, ecological variability in the environment, something which previously was been lacking in state water quality management programs. The upper Great Miami River in Ohio illustrates a case study where bioassessment data documented the efficacy of efforts to permit, fund, and construct municipal treatment systems in restoring aquatic life. In contrast, in the Mahoning River similar administrative actions were inadequate to restore aquatic life in an environment with severe sediment contamination and impacts from combined sewer overflows. A biocriteria-based goal of restoring 75% of aquatic life uses by the year 2000 in Ohio has led to the use of biological data to identify trends and forecast the status and the causes and sources of impairment to Ohio streams, an effort that should affect the strategic focus of our water resource management efforts. A biocriteria-based approach has profoundly influenced strategic planning and priority setting, water quality based permitting, water quality standards, basic monitoring and reporting, nonpoint source assessment, and problem discovery within Ohio EPA.  相似文献   

10.
简述了美国地表水监测管理体系,指出其健全的环境监测体系、完善的标准体系以及充分的信息公开和数据共享是保障水环境质量的基石、关键和枢纽。结合我国水环境监测管理的现状,提出,应加强水环境质量监测的立法工作,进一步完善水污染物排污许可证制度,建立以水环境质量为目标的水环境管理制度体系,进一步加大监测信息公开和数据共享力度,修订更适合我国的水环境质量监测指标。  相似文献   

11.
The science and practice of assessing the status and trends of ecological conditions in great rivers have not kept pace with perturbation wrought on these systems. Participants at a symposium sponsored by the U.S. Environmental Protection Agency (USEPA) and the Council of State Governments concluded that useful and efficient assessments of great river ecosystems require thoughtful alignment of sampling designs, spatial and temporal scales, indicators, management needs, and ecosystem characteristics. Site-specific physical, chemical, and biological data long accumulated by monitoring programs have value but fail to provide the integrated system-wide perspective required for adaptive management and the Clean Water Act. Use of existing data may be limited by methodological incompatibilities, access difficulties, and the exclusive applicability of data to specific habitats or sites. The transition from site-specific to system-wide assessments benefits from research being done by USEPA's Environmental Monitoring and Assessment Program (EMAP) and other programs that use probability surveys and biological indicators. Indicators of various taxa (in particular fish, algae, and benthic invertebrates) have been successfully developed for great rivers. However, optimizing the information these ecological indicators convey to managers and the public is the subject of ongoing research.  相似文献   

12.
Water quality monitoring involves a complex set of steps and a variety of approaches. Its goals include understanding of aquatic habitats, informing management and facilitating decision making, and educating citizens. Environmental nongovernmental organizations (ENGOs) are increasingly engaged in water quality monitoring and act as environmental watchdogs and stewards of water resources. These organizations exhibit different monitoring mandates. As government involvement in water quality monitoring continues to decline, it becomes essential that we understand their modi operandi. By doing so, we can enhance efficacy and encourage data sharing and communication. This research examined Canadian ENGOs that collect their own data on water quality with respect to water quality monitoring activities and information needs. This work had a twofold purpose: (1) to enhance knowledge about the Canadian ENGOs operating in the realm of water quality monitoring and (2) to guide and inform development of web-based geographic information systems (GIS) to support water quality monitoring, particularly using benthic macroinvertebrate protocols. A structured telephone survey was administered across 10 Canadian provinces to 21 ENGOs that undertake water quality monitoring. This generated information about barriers and challenges of data sharing, commonly collected metrics, human resources, and perceptions of volunteer-collected data. Results are presented on an aggregate level and among different groups of respondents. Use of geomatics technology was not consistent among respondents, and we found no noteworthy differences between organizations that did and did not use GIS tools. About one third of respondents did not employ computerized systems (including databases and spreadsheets) to support data management, analysis, and sharing. Despite their advantage as a holistic water quality indicator, benthic macroinvertebrates (BMIs) were not widely employed in stream monitoring. Although BMIs are particularly suitable for the purpose of citizen education, few organizations collected this metric, despite having public education and awareness as part of their mandate.  相似文献   

13.
Coral reefs worldwide are declining at an alarming rate and are under continuous threat from both natural and anthropogenic environmental stressors. Warmer sea temperatures attributed to global climate change and numerous human activities at local scales place these valuable ecosystems at risk. Reefs provide numerous services, including shoreline protection, fishing, tourism and biological diversity, which are lost through physical damage, overfishing, and pollution. Pollution can be controlled under provisions of the Clean Water Act, but these options have not been fully employed to protect coral reefs. No U.S. jurisdiction has implemented coral reef biocriteria, which are narrative or quantitative water quality standards based on the condition of a biological resource or assemblage. The President’s Ocean Action Plan directs the U.S. Environmental Protection Agency (EPA) to develop biological assessment methods and biological criteria for evaluating and maintaining the health of coral reef ecosystems. EPA has formed the Coral Reef Biocriteria Working Group (CRBWG) to foster development of coral reef biocriteria through focused research, evaluation and communication among Agency partners and U.S. jurisdictions. Ongoing CRBWG activities include development and evaluation of a rapid bioassessment protocol for application in biocriteria programs; development of a survey design and monitoring strategy for the U.S. Virgin Islands; comprehensive reviews of biocriteria approaches proposed by states and territories; and assembly of data from a variety of monitoring programs for additional metrics. Guidance documents are being prepared to assist U.S. jurisdictions in reaching protective and defensible biocriteria.  相似文献   

14.
The Micro Prespa basin is a trilateral catchment area of significant importance with a unique ecosystem closely related to the homonymous lake. In this frame, a fully operational monitoring project was carried out including continuous real-time measurements in Micro Prespa Lake with the use of a multi-sensor probe, as well as periodical sampling and analyses of all available water systems for an extended set of 85 parameters. Four main interacting water systems were identified, including alluvial and karstic aquifers, Micro Prespa Lake and adjacent drainage network. The results outlined that general environmental conditions are satisfying in respect to the relative legislation and the hydrogeochemical signatures. However, trends of environmental pressures were ascertained as a result of natural (geogenic) factors, embracing seasonal peaks for Ni, Pb, and NH4 mainly in groundwater systems. Based on chlorophyll a records, Micro Prespa is classified as oligotrophic to slightly mesotrophic, subjected to seasonal variations. Heavy metal concentrations are low, except Ni which appears to have elevated values during the dry hydrological period. Finally, the hydrogeochemistry of drainage network is primarily influenced by surface runoff of the surrounding mountainous areas, hence elevated phosphorus values of the Aghios Germanos stream are possibly linked with the leaching of the granitic formations on the east.  相似文献   

15.
新疆水环境质量监测现状、问题及对策   总被引:1,自引:0,他引:1  
杨春  沈志 《干旱环境监测》2009,23(3):134-137,151
水环境质量监测是环境质量监测的重要组成部分,其任务是说清区域水环境质量现状、问题及变化趋势,为环境管理决策提供依据。本文简要介绍了新疆环保系统的水环境质量监测工作现状及存在问题,并提出了相应的对策建议,以期为进一步改进新疆水环境质量监测与管理工作提供参考。  相似文献   

16.
During the 1994/1995 EMAP-Estauries program in the Carolinian Province we investigated the feasibility of using parasites of fish as response indicators. Parasites of fish are an indigenous component of healthy ecosystems. Within the EMAP-E design, the suite of environmental parameters which may affect parasite abundance, richness, prevalence, and diversity can be divided into three categories: 1) the physical and chemical characteristics of the water and sediment (including contaminants) external to the fish; 2) the internal environment defined by the physical condition (physiological) of individual fish; and 3) the presence and relative abundance of benthic macroinvertebrates, many of which serve as intermediate hosts. The biotic response of parasites to environmental stressors is also reflected in the health of fish. Parasite assemblages of silver perch Bairdiella chrysura respond to both natural and anthropogenic stressors. Our results showed that particular environmental stressors and specific parasites that respond include: temperature and monogeneans; contaminants and nematodes; low dissolved oxygen and protists; and salinity, together with a mixture of metal and organic contaminants and crustacea. Parasites of fish are useful biomarkers and appear to be more sensitive to environmental stressors than are the fish themselves. Parasite responses to selected environmental stressors may be used to discriminate polluted and unpolluted sites. The use of parasites of fish as biomarkers has relevant application to fisheries management and coastal monitoring programs.  相似文献   

17.
Water quality indices (WQIs) have been developed to assess the suitability of water for a variety of uses. These indices reflect the status of water quality in lakes, streams, rivers, and reservoirs. The concept of WQIs is based on a comparison of the concentration of contaminants with the respective environmental standards. The number, frequency, and magnitude by which the environmental standards for specific variables are not met in a given time period are reflected in WQIs. Further, the water quality trend analysis predicts the behavior of the water quality parameters and overall water quality in the time domain. In this paper, the concept of WQI was applied to three selected watersheds of Atlantic region: the Mersey River, the Point Wolfe River, and the Dunk River sites. To have robust study, two different water quality indices are used: Canadian Water Quality Index (CWQI), and British Columbia Water Quality Index (BWQI). The complete study was conducted in two steps. The first step was to organize and process the data into a format compatible with WQI analysis. After processing the input data, the WQI was calculated. The second step outlined in the paper discusses detailed trend analysis using linear and quadratic models for all the three sites. As per the 25 years trend analysis, overall water quality for agriculture use observed an improving trend at all the three sites studied. Water quality for raw water used for drinking (prior to treatment) and aquatic uses has shown improving trend at Point Wolfe River. It is further observed that pH, SO4, and NO3 concentrations are improving at Dunk River, Mersey River, and Point Wolfe River sites. To ascertain the reliability and significance of the trend analysis, a detailed error analysis and parametric significance tests were also conducted It was observed that for most of the sites and water uses quadratic trend models were a better fit than the linear models.  相似文献   

18.
19.
McMurdo Station is the largest research station in Antarctica and has a population that ranges from 250 to 1200 people. Wastewater from the Station is macerated, was sometimes mixed with waste brine from the desalinization plant and is discharged to McMurdo Sound. Effluent water quality has been routinely monitored since 1989, and a special ambient water quality study was conducted by Idaho National Engineering Laboratory (INEL) personnel in 1992. Results of the effluent monitoring efforts show that low concentrations of a few organic contaminants have been detected, while concentrations of metals, particularly copper, are considerably higher. Ambient water quality and sea ice monitoring detected very few contaminants, all at very low levels. Only minor and variable dissolved oxygen depression was detected near the outfall. Diatom communities near the outfall differ in relative abundance, cell counts, and chlorophyll a content compared to control sites. For the purpose of evaluating the impact of McMurdo`s effluent on ambient water quality, improved effluent monitoring and sediment quality monitoring are recommended instead of frequent monitoring of ambient water quality.  相似文献   

20.
乌鲁木齐市饮用水状况卫生监测分析   总被引:2,自引:0,他引:2  
为了评价乌鲁木齐市居民饮用水卫生状况,对该市6个自来水厂的出厂水,末梢水和二次供水的水质及卫生设施进行监督监测。结果表明,该市居民供水水质基本符合国家生活饮水卫生标准规定,但末梢水和二次供水中余氯合格率偏低,分别为61.02%和45%。二次供水设施使用的防水材料均未按国家规定输涉及水产品卫生许可批件。  相似文献   

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