Potential Impacts on Treated Water Quality of Recycling Dewatered Sludge Supernatant during Harmful Cyanobacterial Blooms

Cyanobacterial blooms and the associated release of cyanotoxins pose problems for many conventional water treatment plants due to their limited removal by typical unit operations. In this study, a conventional water treatment process consisting of coagulation, flocculation, sedimentation, filtration, and sludge dewatering was assessed in lab-scale experiments to measure the removal of microcystin-LR and Microcystis aeruginosa cells using liquid chromatography with mass spectrometer (LC-MS) and a hemacytometer, respectively. The overall goal was to determine the effect of recycling cyanotoxin-laden dewatered sludge supernatant on treated water quality. The lab-scale experimental system was able to maintain the effluent water quality below relevant the United States Environmental Protection Agency (US EPA) and World Health Organisation (WHO) standards for every parameter analyzed at influent concentrations of M. aeruginosa above 106 cells/mL. However, substantial increases of 0.171 NTU (Nephelometric Turbidity Unit), 7 × 104 cells/L, and 0.26 µg/L in turbidity, cyanobacteria cell counts, and microcystin-LR concentration were observed at the time of dewatered supernatant injection. Microcystin-LR concentrations of 1.55 µg/L and 0.25 µg/L were still observed in the dewatering process over 24 and 48 h, respectively, after the initial addition of M.aeruginosa cells, suggesting the possibility that a single cyanobacterial bloom may affect the filtered water quality long after the bloom has dissipated when sludge supernatant recycling is practiced.

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Assessment of Radon Levels in Drinking Water Wells in St. Catherine, Jamaica

Journal of Health and Pollution ◽

10.5696/2156-9614-7.16.31 ◽

2017 ◽

Vol 7 (16) ◽

pp. 31-37 ◽

Cited By ~ 3

Author(s):

Leonard Smith ◽

Mitko Voutchkov

Keyword(s):

Water Quality ◽

Drinking Water ◽

Environmental Protection Agency ◽

Monitoring Program ◽

The United States ◽

Drinking Water Quality ◽

World Health ◽

Potential Health ◽

Water Wells ◽

Study Results

Background. Radon is a known carcinogen and contaminant in drinking water wells, but is not monitored in drinking water quality programs in Jamaica. Objective. The present study was conducted to obtain radon data in local drinking water and evaluate potential health risks. The data will contribute to determining the level of compliance to public health criteria for radon and to develop a monitoring program based on the identified risks. Methods. This study assesses the concentration of radon in 22 drinking water wells in the parish of St. Catherine, Jamaica. Samples were collected for radon, with 12 other measurements gathered including pH, conductivity, TDS, alkalinity, hardness, phosphates, nitrates, chloride, sulfates, turbidity, well depth and geological features. The data were analyzed for compliance to international limits and association with geological and other parameters. Results. The average radon level was 18 Bq/L ± 2 Bq/L and varied from a low of 11 Bq/L ± 1 Bq/L to a high of 41 Bq/L ± 1 Bq/L. There was a positive correlation between radon levels and both alkalinity and turbidity. No relationship of any significance, however, was identified with the other physicochemical parameters. All the study results fell within the European Union (EU) limit of 100 Bq/L, and well within the United States Environmental Protection Agency (USEPA) limit of 147 Bq/L. Most of the wells in this parish have radon levels exceeding the proposed USEPA limit of 11 Bq/L. The proposed limits are intended to support radon mitigation programs to manage radon in air. No limits are provided in the newest edition of the World Health Organization's (WHO) Guidelines for Safe Drinking Water Quality. Conclusions. Most wells in the study area met existing international limits. Almost all, however, did not meet the proposed USEPA limit for locations without radon mitigation programs. This indicates the need to establish national screening levels for radon, consistent with WHO and USEPA recommendations. Competing Interests. The authors declare no competing financial interests.

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Worldwide Regulations and Guidelines for Agricultural Water Reuse: A Critical Review

Water ◽

10.3390/w12040971 ◽

2020 ◽

Vol 12 (4) ◽

pp. 971 ◽

Cited By ~ 7

Author(s):

Farshid Shoushtarian ◽

Masoud Negahban-Azar

Keyword(s):

Water Quality ◽

Environmental Protection Agency ◽

Water Reuse ◽

Agricultural Sector ◽

Specific Treatment ◽

The United States ◽

World Health ◽

Agricultural Water ◽

Treatment Processes ◽

Regulations And Guidelines

Water reuse is gaining momentum as a beneficial practice to address the water crisis, especially in the agricultural sector as the largest water consumer worldwide. With recent advancements in wastewater treatment technologies, it is possible to produce almost any water quality. However, the main human and environmental concerns are still to determine what constituents must be removed and to what extent. The main objectives of this study were to compile, evaluate, and compare the current agricultural water reuse regulations and guidelines worldwide, and identify the gaps. In total, 70 regulations and guidelines, including Environmental Protection Agency (EPA), International Organization for Standardization (ISO), Food and Agriculture Organization of the United Nations (FAO), World Health Organization (WHO), the United States (state by state), European Commission, Canada (all provinces), Australia, Mexico, Iran, Egypt, Tunisia, Jordan, Palestine, Oman, China, Kuwait, Israel, Saudi Arabia, France, Cyprus, Spain, Greece, Portugal, and Italy were investigated in this study. These regulations and guidelines were examined to compile a comprehensive database, including all of the water quality monitoring parameters, and necessary treatment processes. In summary, results showed that the regulations and guidelines are mainly human-health centered, insufficient regarding some of the potentially dangerous pollutants such as emerging constituents, and with large discrepancies when compared with each other. In addition, some of the important water quality parameters such as some of the pathogens, heavy metals, and salinity are only included in a small group of regulations and guidelines investigated in this study. Finally, specific treatment processes have been only mentioned in some of the regulations and guidelines, and with high levels of discrepancy.

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Icyano: a cyanobacterial bloom vulnerability index for drinking water treatment plants

Water Science & Technology Water Supply ◽

10.2166/ws.2020.239 ◽

2020 ◽

Vol 20 (8) ◽

pp. 3517-3530

Author(s):

Mário U. G. Barros ◽

João I. R. Leitão ◽

Thaís R. B. T. Aranha ◽

Serhat Simsek ◽

Riley P. Buley ◽

...

Keyword(s):

Water Quality ◽

Water Treatment ◽

Environmental Changes ◽

Cyanobacterial Bloom ◽

Cyanobacterial Blooms ◽

Treatment Technology ◽

Treatment Unit ◽

Direct Filtration ◽

Water Treatment Plants ◽

Pre Treatment

Abstract Managing freshwater systems has become a challenge for global water utilities given that cyanobacterial blooms have been increasing in frequency and intensity. Consequently, a water quality index that uses conventional measurements to assess toxic cyanobacterial hazards and guide the selection of proper treatment technologies could benefit water resource managers about water quality parameters routinely analyzed in line with environmental changes. An index model, called Icyano, showed that chlorophyll-a, cyanobacterial concentration, and total nitrogen were most important for the index. All reservoirs classified as good by Icyano used direct filtration water treatment technology. Many of the medium Icyano-classified reservoirs used a pre-treatment unit followed by a direct filtration unit. Two reservoirs that were classified as bad or very bad have been utilizing pre-treatment + direct filtration or a complete cycle technology, respectively. As the Icyano index increases, water treatment plants should switch from direct filtration to using a pre-treatment to improve finished water quality. Findings from this project suggest that the direct filtration technology initially used in water treatment plants is not capable of meeting the current water quality guidelines in reservoirs that contain adverse water quality conditions, mostly related to an increase in toxic cyanobacterial blooms. As such, based on our findings, we recommend prioritizing financial resources towards pre-treatment technology or changes to more advanced technologies when Icyano index values increase.

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Evaluation of the Efficiency and Quality of the Water of the Al-Hartha Water Treatment Plant in Basra City

Current World Environment ◽

10.12944/cwe.15.1.11 ◽

2020 ◽

Vol 15 (1) ◽

pp. 75-86

Author(s):

Ahmed Sadiq Al Chalabi ◽

Keyword(s):

Water Quality ◽

Water Treatment ◽

Ph Value ◽

Treatment Plant ◽

Water Treatment Plant ◽

World Health Organisation ◽

World Health ◽

Treated Water ◽

Sedimentation Basins ◽

Physical And Chemical

This study was conducted on the Al-Hartha Water Treatment Plant (HWTP), the largest water treatment plant in the city of Basra, during the period from December 2017 to March 2018. This study gives a description of the units and components of the HWTP, and aimed to evaluate the efficiency of the plant by calculating the efficiency of its sedimentation, filtration and sterilisation basins. Additionally, it aimed to examine its water quality by examining the physical and chemical characteristics of the raw water and treated water at this plant and then comparing the findings with the World Health Organisation (WHO) and Iraqi standard limitations. The results of this study showed that the efficiency of the sedimentation basins is 57%, while the efficiency of the filtration basins is 13.3%, and the sterilisation efficiency ranges from 27 to 50%. The laboratory results for the treated water quality have shown that the turbidity is equal to 12.8 NTU, electrical conductivity (EC) is equal to 7750 µs/cm, the total salt concentration of the total dissolved solids (TDS) is equal to 5200 mg/l, and the concentration of the total suspended solids (TSS) is equal to 65 mg/l of the water outside from the HWTP. All these water quality results are higher than the WHO and Iraqi standard limitations, except the pH value of 6.95, which is within the permissible limits.

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Picking Up Where the TMDL Leaves Off: Using the Partnership Wild and Scenic River Framework for Collaborative River Restoration

Sustainability ◽

10.3390/su13041878 ◽

2021 ◽

Vol 13 (4) ◽

pp. 1878

Author(s):

Alan R. Hunt ◽

Meiyin Wu ◽

Tsung-Ta David Hsu ◽

Nancy Roberts-Lawler ◽

Jessica Miller ◽

...

Keyword(s):

Water Quality ◽

Environmental Protection Agency ◽

Bacterial Contamination ◽

Resource Constraints ◽

Clean Water Act ◽

The United States ◽

Clean Water ◽

Private Land ◽

The Public ◽

Wild And Scenic Rivers

The National Wild and Scenic Rivers Act protects less than ¼ of a percent of the United States’ river miles, focusing on free-flowing rivers of good water quality with outstandingly remarkable values for recreation, scenery, and other unique river attributes. It predates the enactment of the Clean Water Act, yet includes a clear anti-degradation principle, that pollution should be reduced and eliminated on designated rivers, in cooperation with the federal Environmental Protection Agency and state pollution control agencies. However, the federal Clean Water Act lacks a clear management framework for implementing restoration activities to reduce non-point source pollution, of which bacterial contamination impacts nearly 40% of the Wild and Scenic Rivers. A case study of the Musconetcong River, in rural mountainous New Jersey, indicates that the Wild and Scenic Rivers Act can be utilized to mobilize and align non-governmental, governmental, philanthropic, and private land-owner resources for restoring river water quality. For example, coordinated restoration efforts on one tributary reduced bacterial contamination by 95%, surpassing the TMDL goal of a 93% reduction. Stakeholder interviews and focus groups indicated widespread knowledge and motivation to improve water quality, but resource constraints limited the scale and scope of restoration efforts. The authors postulate that the Partnership framework, enabled in the Wild and Scenic Rivers Act, facilitated neo-endogenous rural development through improving water quality for recreational usage, whereby bottom-up restoration activities were catalyzed via federal designation and resource provision. However, further efforts to address water quality via voluntary participatory frameworks were ultimately limited by the public sector’s inadequate funding and inaction with regard to water and wildlife resources in the public trust.

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Assessing clarity of message communication for mandated USEPA drinking water quality reports

Journal of Water and Health ◽

10.2166/wh.2015.134 ◽

2015 ◽

Vol 14 (2) ◽

pp. 223-235 ◽

Cited By ~ 2

Author(s):

Katherine Phetxumphou ◽

Siddhartha Roy ◽

Brenda M. Davy ◽

Paul A. Estabrooks ◽

Wen You ◽

...

Keyword(s):

Water Quality ◽

Drinking Water ◽

Environmental Protection Agency ◽

Water System ◽

System Size ◽

The United States ◽

National Sample ◽

Evaluation Tool ◽

Index Index ◽

State Of The Science

The United States Environmental Protection Agency mandates that community water systems (CWSs), or drinking water utilities, provide annual consumer confidence reports (CCRs) reporting on water quality, compliance with regulations, source water, and consumer education. While certain report formats are prescribed, there are no criteria ensuring that consumers understand messages in these reports. To assess clarity of message, trained raters evaluated a national sample of 30 CCRs using the Centers for Disease Control Clear Communication Index (Index) indices: (1) Main Message/Call to Action; (2) Language; (3) Information Design; (4) State of the Science; (5) Behavioral Recommendations; (6) Numbers; and (7) Risk. Communication materials are considered qualifying if they achieve a 90% Index score. Overall mean score across CCRs was 50 ± 14% and none scored 90% or higher. CCRs did not differ significantly by water system size. State of the Science (3 ± 15%) and Behavioral Recommendations (77 ± 36%) indices were the lowest and highest, respectively. Only 63% of CCRs explicitly stated if the water was safe to drink according to federal and state standards and regulations. None of the CCRs had passing Index scores, signaling that CWSs are not effectively communicating with their consumers; thus, the Index can serve as an evaluation tool for CCR effectiveness and a guide to improve water quality communications.

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Cyanobacteria and microcystin contamination in untreated and treated drinking water in Ghana

Advances in Oceanography and Limnology ◽

10.4081/aiol.2017.6323 ◽

2017 ◽

Vol 8 (1) ◽

Cited By ~ 1

Author(s):

Gloria Naa Dzama Addico ◽

Jörg D. Hardege ◽

Jiri Kohoutek ◽

Kweku Amoaku Atta DeGraft-Johnson ◽

Pavel Babica

Keyword(s):

Drinking Water ◽

Water Treatment ◽

Human Health ◽

Metropolitan Area ◽

Cyanobacterial Blooms ◽

Maximal Concentration ◽

Raw Water ◽

Treated Water ◽

Treated Drinking Water ◽

Who Guideline

Although cyanobacterial blooms and cyanotoxins represent a worldwide-occurring phenomenon, there are large differences among different countries in cyanotoxin-related human health risk assessment, management practices and policies. While national standards, guideline values and detailed regulatory frameworks for effective management of cyanotoxin risks have been implemented in many industrialized countries, the extent of cyanobacteria occurrence and cyanotoxin contamination in certain geographical regions is under-reported and not very well understood. Such regions include major parts of tropical West and Central Africa, a region constisting of more than 25 countries occupying an area of 12 million km2, with a total population of 500 milion people. Only few studies focusing on cyanotoxin occurrence in this region have been published so far, and reports dealing specifically with cyanotoxin contamination in drinking water are extremely scarce. In this study, we report seasonal data on cyanobacteria and microcystin (MC) contamination in drinking water reservoirs and adjacent treatment plants located in Ghana, West Africa. During January-June 2005, concentrations of MCs were monitored in four treatment plants supplying drinking water to major metropolitan areas in Ghana: the treatment plants Barekese and Owabi, which serve Kumasi Metropolitan Area, and the plants Kpong and Weija, providing water for Accra-Tema Metropolitan Area. HPLC analyses showed that 65% samples of raw water at the intake of the treatment plants contained intracellular MCs (maximal detected concentration was 8.73 µg L-1), whereas dissolved toxins were detected in 33% of the samples. Significant reduction of cyanobacterial cell counts and MC concentrations was achieved during the entire monitoring period by the applied conventional water treatment methods (alum flocculation, sedimentation, rapid sand filtration and chlorination), and MC concentration in the final treated water never exceeded 1 µg L-1 (WHO guideline limit for MCs in drinking water). However, cyanobacterial cells (93-3,055 cell mL-1) were frequently found in the final treated water and intracellular MCs were detected in 17% of the samples (maximal concentration 0.61 µg L-1), while dissolved MCs were present in 14% of the final treated water samples (maximal concentration 0.81 µg L-1). It indicates a borderline efficiency of the water treatment, thus MC concentrations in drinking water might exceed the WHO guideline limit if the treatment efficiency gets compromised. In addition, MC concentrations found in the raw water intake might represent significant human health risks for people living in areas with only a limited access to the treated or underground drinking water.

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Carbonaceous Aerosols in Fine Particulate Matter of Santiago Metropolitan Area, Chile

The Scientific World JOURNAL ◽

10.1155/2014/794590 ◽

2014 ◽

Vol 2014 ◽

pp. 1-12 ◽

Cited By ~ 7

Author(s):

Richard Toro Araya ◽

Robert Flocchini ◽

Rául G. E. Morales Segura ◽

Manuel A. Leiva Guzmán

Keyword(s):

Particulate Matter ◽

Organic Carbon ◽

Environmental Protection Agency ◽

Fine Particulate Matter ◽

Warm Season ◽

The United States ◽

Carbonaceous Aerosol ◽

World Health ◽

Carbonaceous Aerosols ◽

Fine Particulate

Measurements of carbonaceous aerosols in South American cities are limited, and most existing data are of short term and limited to only a few locations. For 6 years (2002–2007), concentrations of fine particulate matter and organic and elemental carbon were measured continuously in the capital of Chile. The contribution of carbonaceous aerosols to the primary and secondary fractions was estimated at three different sampling sites and in the warm and cool seasons. The results demonstrate that there are significant differences in the levels in both the cold (March to August) and warm (September to February) seasons at all sites studied. The percent contribution of total carbonaceous aerosol fine particulate matter was greater in the cool season (53 ± 41%) than in the warm season (44 ± 18%). On average, the secondary organic carbon in the city corresponded to 29% of the total organic carbon. In cold periods, this proportion may reach an average of 38%. A comparison of the results with the air quality standards for fine particulate matter indicates that the total carbonaceous fraction alone exceeds the World Health Organization standard (10 µg/m3) and the United States Environmental Protection Agency standard (15 µg/m3) for fine particulate matter.

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Water Quality Assessment of Cimanuk River in West Java Using Pollution Index

E3S Web of Conferences ◽

10.1051/e3sconf/20186804009 ◽

2018 ◽

Vol 68 ◽

pp. 04009 ◽

Cited By ~ 2

Author(s):

Ihya Sulthonuddin ◽

Djoko Mulyo Hartono ◽

Suyud Warno Utomo

Keyword(s):

Water Quality ◽

Environmental Protection Agency ◽

Government Regulation ◽

Pollution Index ◽

Quality Standard ◽

World Health ◽

West Java ◽

Index Method ◽

Water Quality Standard

Cimanuk river is one of the seven rivers in West Java. Cimanuk river pollution is indicated to have suffered as a result of the activity of domestic waste, industrial and agricultural uncontrolled in the riparian area of Cimanuk river. This research aims to analize water quality of Cimanuk river based on water quality standard on Government Regulation of Republic of Indonesia (IDN), Regulation of the Governor of West Java (WJ), World Health Organization (WHO), Enviromental Standard of United Kingdom (UK), Environmental Protection Agency (EPA), Enviromental Quality Standard (EQS), and Department of Environment (DOE). This research used pollution index method. The result is water quality of Cimanuk river not meet water quality standard where the TSS (94.85±84,60 mg/L), BOD (9.61±3.16 mg/L), COD (37.69±14.01 mg/L), DO (5.12±1.22 mg/L), NH3N (0.25±0.24 mg/L). Degradation of water quality of Cimanuk river from upstream to downstream marked by increased pollution index value annually. Pollution index of Cimanuk river ranging from 1.25 to 20.31. Water quality status of Cimanuk river has been from lightly polluted to heavilypolluted.

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Investigating disinfectant by-products in Harare potable water supply, Zimbabwe

Journal of Water Sanitation and Hygiene for Development ◽

10.2166/washdev.2018.104 ◽

2018 ◽

Vol 8 (3) ◽

pp. 415-428 ◽

Cited By ~ 4

Author(s):

Kuitakwashe Nhongo ◽

Zvikomborero Hoko ◽

Jameson Kugara

Keyword(s):

Water Supply ◽

Environmental Protection Agency ◽

Distribution System ◽

Water Distribution ◽

The United States ◽

World Health ◽

Residual Chlorine ◽

By Products ◽

Trihalomethanes Formation

Abstract Formation of disinfectant by-products was investigated in the Harare water supply system from February to April 2015. Sampling sites were selected from the lake, Morton Jaffray Water Treatment Works and critical points in the distribution system. The spatial variations of trihalomethanes and selected water quality parameters were investigated for 15 sampling points in 5 sampling campaigns to assess suitability for drinking. All trihalomethane species were measured, namely chloroform, bromodichloromethane, dibromochloromethane and bromoform. Only chloroform and bromodichloromethane were detected. The study confirmed that there is trihalomethanes formation in the Harare water distribution system and that it is affected by the residence time and presence of organic matter in the system. However, the levels of trihalomethanes are generally within the levels suggested by the World Health Organization. Only bromodichloromethane presents a risk for long-term exposure as it had levels that exceeded the limit for long-term exposure suggested by the United States Environmental Protection Agency. Bromodichloromethane, turbidity and free residual chlorine levels were not suitable for drinking in some of the zones. Boosting of chlorine residuals is necessary especially in areas with free chlorine less than 0.2 mg/L. Injection of ammonia, periodic cleaning of storage reservoirs, and flushing of lines will reduce trihalomethanes formation.

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