scholarly journals Detection of Cryptosporidium species and sources of contamination with Cryptosporidium hominis during a waterborne outbreak in north west Wales

2009 ◽  
Vol 8 (2) ◽  
pp. 311-325 ◽  
Author(s):  
Rachel M. Chalmers ◽  
Guy Robinson ◽  
Kristin Elwin ◽  
Stephen J. Hadfield ◽  
Euron Thomas ◽  
...  
Keyword(s):  
Wastewater Treatment ◽  
Water Supply ◽  
Treatment Plant ◽  
Small Subunit ◽  
Base Flow ◽  
Septic Tank ◽  
Cryptosporidium Hominis ◽  
Genotype I ◽  
Waterborne Outbreak ◽  
North West

As part of investigations into the cause of a waterborne outbreak of Cryptosporidium hominis infection linked to a mains water supply, surface waters and wastewater treatment plants were tested for Cryptosporidium spp. Oocyst counts in base flow surface water samples ranged from nil to 29 per 10 l. Oocyst counts in effluent from a community wastewater treatment plant were up to 63 fold higher and breakout from one septic tank five logs higher. There were no peak (storm) flow events during the investigation. C. hominis, four named genotypes (cervine, muskrat II, rat, W19) and six new small subunit ribosomal RNA gene sequences were identified. Four of the new sequences were closely related to Cryptosporidium muskrat genotype I, one was closely related to the fox genotype and one to Cryptosporidium canis. C. hominis was found extensively in the catchment, but only at sites contaminated by wastewater, and in the treated water supply to the affected area. All were gp60 subtype IbA10G2, the outbreak subtype. Multiple routes of contamination of the reservoir were identified, resulting in persistent detection of low numbers of oocysts in the final water. This work demonstrates the utility of genotyping Cryptosporidium isolates in environmental samples during outbreak investigations.

Management of the Occoquan River basin: a 20-year case history

1995 ◽  
Vol 32 (5-6) ◽  
pp. 235-243 ◽  
Author(s):  
C. W. Randall ◽  
T. J. Grizzard
Keyword(s):  
Water Quality ◽  
Land Use ◽  
Drinking Water ◽  
Wastewater Treatment ◽  
Water Supply ◽  
Land Use Changes ◽  
Treatment Plant ◽  
Water Reservoir ◽  
Land Use Management ◽  
Early Results

The high dam on the Occoquan River of Northern Virginia, United States of America, was constructed in 1957, forming a drinking water reservoir with a capacity of 37.1 × 106m3 formed by drainage from a 1 460 km2 watershed, and providing a safe yield of 189 251 m3 per day. Deteriorating water quality in the late 1960s led to a special “policy” for the watershed, designed to preserve the reservoir as a drinking water supply. Key provisions of the policy mandated replacement of the watershed's 11 publicly owned wastewater treatment works with a single advanced wastewater treatment plant (AWT), and establishment of the Occoquan Watershed Monitoring Programme. Early results from the programme established non-point nutrient pollution as a major cause of water quality deterioration and resulted in the implementation of non-point pollution controls throughout the watershed during the late 1970s. The AWT plant went on-line in July 1978. Continuous monitoring since 1973 has demonstrated both the necessity and the effectiveness of point and non-point nutrient controls for the preservation of the reservoir's water quality. The AWT plant provides excellent removal of organics and phosphorus, plus complete nitrification. The nitrates are discharged to the receiving stream to enhance conditions in the reservoir. Control policies include land-use management for the preservation of this essential water supply for 750 000 people in the Washington, D.C. suburbs. Land-use management decisions are based on the results obtained with a watershed-reservoir linked computer model which predicts water quality changes resulting from land-use changes.

scholarly journals Meta-Analysis of the Reduction of Norovirus and Male-Specific Coliphage Concentrations in Wastewater Treatment Plants

2015 ◽  
Vol 81 (14) ◽  
pp. 4669-4681 ◽  
Author(s):  
Régis Pouillot ◽  
Jane M. Van Doren ◽  
Jacquelina Woods ◽  
Daniel Plante ◽  
Mark Smith ◽  
...  
Keyword(s):  
United States ◽  
Wastewater Treatment ◽  
Meta Analysis ◽  
Treatment Plant ◽  
Credible Interval ◽  
The United States ◽  
Genotype I ◽  
Chlorine Disinfection ◽  
The Mean ◽  
Male Specific

ABSTRACTHuman norovirus (NoV) is the leading cause of foodborne illness in the United States and Canada. Wastewater treatment plant (WWTP) effluents impacting bivalve mollusk-growing areas are potential sources of NoV contamination. We have developed a meta-analysis that evaluates WWTP influent concentrations and log10reductions of NoV genotype I (NoV GI; in numbers of genome copies per liter [gc/liter]), NoV genotype II (NoV GII; in gc/liter), and male-specific coliphage (MSC; in number of PFU per liter), a proposed viral surrogate for NoV. The meta-analysis included relevant data (2,943 measurements) reported in the scientific literature through September 2013 and previously unpublished surveillance data from the United States and Canada. Model results indicated that the mean WWTP influent concentration of NoV GII (3.9 log10gc/liter; 95% credible interval [CI], 3.5, 4.3 log10gc/liter) is larger than the value for NoV GI (1.5 log10gc/liter; 95% CI, 0.4, 2.4 log10gc/liter), with large variations occurring from one WWTP to another. For WWTPs with mechanical systems and chlorine disinfection, mean log10reductions were −2.4 log10gc/liter (95% CI, −3.9, −1.1 log10gc/liter) for NoV GI, −2.7 log10gc/liter (95% CI, −3.6, −1.9 log10gc/liter) for NoV GII, and −2.9 log10PFU per liter (95% CI, −3.4, −2.4 log10PFU per liter) for MSCs. Comparable values for WWTPs with lagoon systems and chlorine disinfection were −1.4 log10gc/liter (95% CI, −3.3, 0.5 log10gc/liter) for NoV GI, −1.7 log10gc/liter (95% CI, −3.1, −0.3 log10gc/liter) for NoV GII, and −3.6 log10PFU per liter (95% CI, −4.8, −2.4 PFU per liter) for MSCs. Within WWTPs, correlations exist between mean NoV GI and NoV GII influent concentrations and between the mean log10reduction in NoV GII and the mean log10reduction in MSCs.

scholarly journals Assessment of the technological reliability of a hybrid constructed wetland for wastewater treatment in a mountain eco-tourist farm in Poland

2017 ◽  
Vol 75 (11) ◽  
pp. 2649-2658 ◽  
Author(s):  
Andrzej Jucherski ◽  
Maria Nastawny ◽  
Andrzej Walczowski ◽  
Krzysztof Jóźwiakowski ◽  
Magdalena Gajewska
Keyword(s):  
Wastewater Treatment ◽  
Treatment Plant ◽  
Oxygen Demand ◽  
Operational Reliability ◽  
Septic Tank ◽  
Clay Material ◽  
Lognormal Distributions ◽  
Total Nitrogen Removal ◽  
High Level ◽  
Test Treatment

The aim of the present study was to assess the technological reliability of a domestic hybrid wastewater treatment installation consisting of a classic three-chambered (volume 6 m3) septic tank, a vertical flow trickling bed filled with granules of a calcinated clay material (KERAMZYT), a special wetland bed constructed on a slope, and a permeable pond used as a receiver. The test treatment plant was located at a mountain eco-tourist farm on the periphery of the spa municipality of Krynica-Zdrój, Poland. The plant's operational reliability in reducing the concentration of organic matter, measured as biochemical oxygen demand (BOD5) and chemical oxygen demand (COD), was 100% when modelled by both the Weibull and the lognormal distributions. The respective reliability values for total nitrogen removal were 76.8% and 77.0%, total suspended solids – 99.5% and 92.6%, and PO4-P – 98.2% and 95.2%, with the differences being negligible. The installation was characterized by a very high level of technological reliability when compared with other solutions of this type. The Weibull method employed for statistical evaluation of technological reliability can also be used for comparison purposes. From the ecological perspective, the facility presented in the study has proven to be an effective tool for protecting local aquifer areas.

scholarly journals Variable dynamics of sewage supply to wastewater treatment plant depending on the amount of precipitation water inflowing to sewerage network

2017 ◽  
Vol 33 (1) ◽  
pp. 57-63 ◽  
Author(s):  
Piotr M. Bugajski ◽  
Grzegorz Kaczor ◽  
Krzysztof Chmielowski
Keyword(s):  
Wastewater Treatment ◽  
Water Supply ◽  
Wastewater Treatment Plant ◽  
Treatment Plant ◽  
Sewerage System ◽  
Sewage System ◽  
Treated Sewage ◽  
Precipitation Water ◽  
Sewerage Network ◽  
Maximum Design

AbstractThe paper analyzes the effect of precipitation water that inflowing to sanitary sewage system as accidental water on the changes in the total amount of treated sewage. The effects of accidental water supply on the total amount of sewage inflowing to treatment plant were analyzed based on mean daily amounts from the investigated periods and mean daily amounts from incidental supplies. The study was conducted in the years 2010–2015. Six characteristic research periods were identified (one per each calendar year), when the amount of sewage in the sanitary sewage system was greater than during dry weather. The analysis of changes in the amount of sewage supplied to the sewerage system in the six investigated periods revealed that the accidental water constituted from 26.8% to 48.4% of total sewage inflowing to the wastewater treatment plant (WWTP). In exceptional situations, during intense rains, the share of precipitation water in the sewerage system would increase up to 75%. Then, the rainwater inflowing the sewerage system caused hydraulic overloading of the WWTP by exceeding its maximum design supply.

scholarly journals The small Wastewater Treatment Plants – Hydrobotanical Systems in Environmental Protection

2013 ◽  
Vol 39 (1) ◽  
pp. 3-16 ◽  
Author(s):  
Katarzyna Pawęska ◽  
Krzysztof Kuczewski
Keyword(s):  
Wastewater Treatment ◽  
Constructed Wetland ◽  
Mechanical Treatment ◽  
Wastewater Treatment Plants ◽  
Treatment Plant ◽  
Domestic Sewage ◽  
Septic Tank ◽  
Educational Institutions ◽  
Wetland Treatment

Abstract The paper presents results of research concerning operating of five small wastewater treatment plants working in two different technologies: hydrobotanical wastewater treatment plant and constructed wetland. Each object was designed for the treatment of domestic sewage after preliminary mechanical treatment in a septic tank. Hydrobotanical wastewater treatment plants and one of constructed wetland beds were built for treating sewage produced in educational institutions and resort. In the article attention is paid to possibility of exceeding the maximum allowable concentration of pollutants for three main indicators of pollution: BOD5, COD, and total suspension. The reduction of these indices is required by the Regulation of the Minister of Environment [14] for wastewater treatment plants with PE < 2000. In addition, the paper presents the effects of wastewater treatment to reduce biogens. The best quality of outflow was reached by outflows from constructed wetland treatment plants. None of the observed objects fulfilled the requirements in terms of allowable concentrations for total suspension. The most effective were objects operating in technology of “constructed wetland”.

Engineered ecosystem for on-site wastewater treatment in tropical areas

2012 ◽  
Vol 66 (10) ◽  
pp. 2131-2137 ◽  
Author(s):  
André Luis de Sá Salomão ◽  
Marcia Marques ◽  
Raul Gonçalves Severo ◽  
Odir Clécio da Cruz Roque
Keyword(s):  
Wastewater Treatment ◽  
Aquatic Macrophytes ◽  
Suspended Solids ◽  
Treatment Options ◽  
Treatment Plant ◽  
Oxygen Demand ◽  
Septic Tank ◽  
Decentralized Wastewater Treatment ◽  
Tropical Areas ◽  
Aerated Filter

There is a worldwide demand for decentralized wastewater treatment options. An on-site engineered ecosystem (EE) treatment plant was designed with a multistage approach for small wastewater generators in tropical areas. The array of treatment units included a septic tank, a submersed aerated filter, and a secondary decanter followed by three vegetated tanks containing aquatic macrophytes intercalated with one tank of algae. During 11 months of operation with a flow rate of 52 L h−1, the system removed on average 93.2% and 92.9% of the chemical oxygen demand (COD) and volatile suspended solids (VSS) reaching final concentrations of 36.3 ± 12.7 and 13.7 ± 4.2 mg L−1, respectively. Regarding ammonia-N (NH4-N) and total phosphorus (TP), the system removed on average 69.8% and 54.5% with final concentrations of 18.8 ± 9.3 and 14.0 ± 2.5 mg L−1, respectively. The tanks with algae and macrophytes together contributed to the overall nutrient removal with 33.6% for NH4-N and 26.4% for TP. The final concentrations for all parameters except TP met the discharge threshold limits established by Brazilian and EU legislation. The EE was considered appropriate for the purpose for which it was created.

scholarly journals Physico-chemical investigation of wastewater from the Sebdou-Tlemcen textile complex North-West Algeria

2021 ◽  
Vol 6 (2) ◽  
pp. 361-370
Author(s):  
Asma Khelassi- Sefaoui ◽  
Abderrahmane Khechekhouche ◽  
Manel Zaoui-Djelloul Daouadji ◽  
Hamza Idrici
Keyword(s):  
Wastewater Treatment ◽  
Chemical Oxygen Demand ◽  
Water Temperature ◽  
Biochemical Oxygen Demand ◽  
Suspended Solids ◽  
Treatment Plant ◽  
Oxygen Demand ◽  
North West ◽  
Physico Chemical ◽  
West Algeria

Wastewater treatment is a process used in several countries, particularly in Algeria. A study on Earth for one month was carried out at the sewage plant of the Sebdou textile complex, Tlemcen, north-west of Algeria. Regular samples gave average values at the outlet such that the water temperature is 22 ° C, the ph 7.43, the biochemical oxygen demand BOD5 is 36.5 mg / l, the chemical oxygen demand COD vary between 100 and 200 mg / l at the exit of the WWTP mg / l and finally suspended solids SS is of the order of 36.2 mg / l. All these values conform with the standards and therefore the treatment plant operates within Algerian standards.

Elements for setting up discharge standards in developing countries based on actual wastewater treatment plant performance

2008 ◽  
Vol 58 (10) ◽  
pp. 2001-2008 ◽  
Author(s):  
Sílvia C. Oliveira ◽  
Marcos von Sperling
Keyword(s):  
Developing Countries ◽  
Wastewater Treatment ◽  
Treatment Plant ◽  
Poor Performance ◽  
Plant Performance ◽  
Septic Tank ◽  
Best Available Technologies ◽  
Treatment Processes ◽  
Wide Range ◽  
Uasb Reactors

The paper analyses the capability of 166 full-scale wastewater treatment plants operating in Brazil, in order to achieve different quality targets for wastewater discharge. These targets cover a wide range of possible situations, reflecting usual practices adopted worldwide. Six different treatment processes have been investigated: septic tank + anaerobic filter, facultative pond, anaerobic pond + facultative pond, activated sludge, UASB reactors alone, UASB reactors followed by post-treatment. The parameters investigated were: BOD, COD, suspended solids, total nitrogen, total phosphorus and thermotolerant coliforms. Most technologies showed a poor performance, and some of them were not capable to achieve even relaxed standards. The paper presents elements for setting up discharge standards in developing countries, based either on values that may be achieved by treatment processes commonly applied or on best available technologies.

scholarly journals Baseline carbon emission assessment in water utilities in Jordan using ECAM tool

2019 ◽  
Vol 68 (6) ◽  
pp. 460-473 ◽  
Author(s):  
Motasem Saidan ◽  
Hussam J. Khasawneh ◽  
Hassan Aboelnga ◽  
Sureyya Meric ◽  
Ioannis Kalavrouziotis ◽  
...  
Keyword(s):  
Wastewater Treatment ◽  
Water Supply ◽  
Carbon Emissions ◽  
Distribution Systems ◽  
Energy Use ◽  
Ghg Emissions ◽  
Treatment Plant ◽  
Energy Performance ◽  
Water Utilities ◽  
Ghg Reduction

Abstract This study presents a baseline assessment of carbon emissions in water utilities in Madaba, Jordan. The Energy Performance and Carbon Emissions Assessment and Monitoring Tool (ECAM) is applied in the present study in order to reduce indirect and direct emissions. Input data for the assessment included inter alia, population, water volumes, energy consumption, and type of wastewater treatment. The methodology focuses on the greenhouse gas (GHG) emissions and energy use that is directly associated with the utility operations covering the whole water cycle. The ECAM's Quick Assessment revealed that 89.7% of the energy is consumed in abstraction and distribution systems of water supply, whereas wastewater collection, treatment, and discharge consumed only 10.3% in Madaba. The detailed ECAM tool assessment results showed that total GHG emissions from the entire water and wastewater system in Madaba are approximately 28.122 million kg CO2/year. The water supply is the major contributor to GHG accounting for 62.4%, while 37.6% of GHG emissions result from sewage treatment, and are associated with treatment process requirements considered in this work, in addition to sludge transport from septic tanks to the wastewater treatment plant. The findings of this work can help the utility to undertake energy efficiency and GHG reduction measures.

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