Off flavours in large waterbodies: physics, chemistry and biology in synchrony

2007 ◽  
Vol 55 (5) ◽  
pp. 1-8 ◽  
Author(s):  
S.B. Watson ◽  
M. Charlton ◽  
Y.R. Rao ◽  
T. Howell ◽  
J. Ridal ◽  
...  
Keyword(s):  
Spatial Dynamics ◽  
Water Source ◽  
Past Century ◽  
Drinking Water Source ◽  
Physical Size ◽  
Spatial And Temporal Scales ◽  
Large Systems ◽  
Management Approaches ◽  
St Lawrence River

The Laurentian Great Lakes of North America are a drinking water source for millions of Canadian and US consumers. These waterbodies have undergone extensive change over the past century as a result of widespread degradation and remediation. Many of the Lakes are prone to taste and odour (T&O), and although these outbreaks have been poorly monitored, evidence suggests that they are increasing in frequency. Tracing and controlling T&O in such large systems presents a challenging task, due to their physical size and complexity. This paper presents an overview of recent investigative and management approaches to T&O in Lake Ontario and its outflow, the St. Lawrence River. We have identified three distinct patterns of T&O in these source-waters, caused by geosmin and 2-methylisoborneol and differing in their planktonic and benthic sources, and temporal and spatial dynamics. Each pattern has required a different approach by scientists and management, in partnership with the water industry. We have shown these T&O outbreaks are caused and moderated by physical, chemical and biological mechanisms over a spectrum of spatial and temporal scales. Canadian municipalities affected by these outbreaks have been key to the investigation of the links between T&O and ecosystem processes with the aim to develop more proactive water treatment and long-term management.

scholarly journals Sustained use of a household-scale water filtration device in rural Cambodia

2009 ◽  
Vol 7 (3) ◽  
pp. 404-412 ◽  
Author(s):  
Joe Brown ◽  
S. Proum ◽  
M. D. Sobsey
Keyword(s):  
Water Treatment ◽  
Water Source ◽  
Drinking Water Source ◽  
Ceramic Water Filters ◽  
Hygiene Practices ◽  
Point Of Use ◽  
Sanitation And Hygiene ◽  
Water Filters ◽  
Over Time

The effectiveness of point-of-use water treatment may be limited by declining use over time, particularly when water treatment is introduced via targeted intervention programmes. In order to evaluate the long-term uptake and use of locally produced ceramic water filters in rural Cambodia, we visited households that had received filters as part of NGO-subsidized distribution programmes over a 4 year period from 2002 to 2006. Of the more than 2,000 filters distributed, we visited 506 randomly selected households in 13 villages spanning three provinces to assess filter time in use and to collect data on factors potentially correlated with long-term use. Results indicate that filter use declined at the rate of approximately 2% per month after implementation, largely owing to breakages, and that, controlling for time since implementation, continued filter use over time was most closely positively associated with: related water, sanitation and hygiene practices in the home; cash investment in the technology by the household; and use of surface water as a primary drinking water source.

scholarly journals Norovirus Dynamics in Wastewater Discharges and in the Recipient Drinking Water Source: Long-Term Monitoring and Hydrodynamic Modeling

2016 ◽  
Vol 50 (20) ◽  
pp. 10851-10858 ◽  
Author(s):  
Olaf Dienus ◽  
Ekaterina Sokolova ◽  
Fredrik Nyström ◽  
Andreas Matussek ◽  
Sture Löfgren ◽  
...  
Keyword(s):  
Drinking Water ◽  
Water Source ◽  
Hydrodynamic Modeling ◽  
Drinking Water Source ◽  
Long Term Monitoring ◽  
Term Monitoring

NGO's “come back ayufish” campaign and preservation of drinking water sources in Murasaki River, Kitakyushu city, Japan

2006 ◽  
Vol 6 (2) ◽  
pp. 223-230
Author(s):  
A. Hashimoto
Keyword(s):  
Drinking Water ◽  
Water Source ◽  
Raw Material ◽  
Drinking Water Source ◽  
Japanese People ◽  
Quality Product ◽  
Physiological Impact ◽  
The Relationship ◽  
Term Monitoring

Good quality raw material gives a good quality product. This is a fundamental rule of production not only for commodities but also for our drinking water. The citizens of Kitakyushu city have been aware of this rule and started the campaign to preserve the drinking water source, and its surrounding natural environment. The catchphrase for the campaign is “Come back Ayufish to the river”. For Japanese people, ayufish is one of the most suitable indicators of clean water or clean river. More than a thousand citizens take part in this campaign every year. A group of environmental chemists have supported this campaign by sharing the long-term monitoring data for 40 years with the NGO and also the relationship between physiological impact of water quality such as BOD and MBAS on the behavior of ayufish to return to the river is discussed.

scholarly journals Temporal changes in distributions and the species atlas: How can British and Irish plant data shoulder the inferential burden?

2019 ◽  
Vol 1 (4) ◽  
pp. 250-282 ◽  
Author(s):  
Oliver L. Pescott ◽  
Thomas A. Humphrey ◽  
Peter A. Stroh ◽  
Kevin J. Walker
Keyword(s):  
Linear Models ◽  
Reporting Rate ◽  
Distribution Data ◽  
Past Century ◽  
Time Varying ◽  
Occupancy Models ◽  
Occupancy Modelling ◽  
Spatial And Temporal Scales ◽  
Smoothing Methods

Species distribution atlases often rely on volunteer effort to achieve their desired coverage, an activity now typically discussed, at least in academia, under the general theme of “citizen science”. Such data, however, are rarely without complex biases, particularly with respect to the estimation of trends in species’ distributions over many decades. The data of the Botanical Society of Britain and Ireland (BSBI) are no exception to this, and both careful thought in data aggregation (spatial, temporal, and taxonomic) and appropriate modelling procedures are required to overcome these challenges. We discuss these issues, with a primary focus on the statistical models that have been put forward to adjust for such biases. Such models include the Telfer method, various “reporting rate” approaches based on generalised linear models, the frequency scaling using local occupancy (“Frescalo”) model, occupancy models, and spatial smoothing methods. In each case the strengths and limitations in relation to estimating trends from distribution data with important time-varying biases are assessed. Various properties of BSBI data, in particular the increasing numbers of records at fine spatial and temporal scales over the past century, coupled with a general lack of re-visits to sites at such finer scales and the time-varying biases previously mentioned, imply that methods that can be sensibly applied at coarser levels are likely to be most appropriate for estimating accurate long-term trends in distributions. We conclude that Frescalo, which can be seen as a type of occupancy model where an adjustment for overlooked species is made in relation to spatial rather than temporal replication, whilst simultaneously adjusting for variable regional effort, is currently the most sophisticated tool for achieving this. Although recording community-accepted adjustments to data collection practices may allow for a greater application of occupancy modelling or other approaches in the future, methods that seek accurate trends over the long-term are necessarily limited either to scales at which various properties of the data in hand are most likely to be unbiased, or at which the biases are well enough understood to be modelled accurately.

scholarly journals Impact of climate forecasts on the microbial quality of a drinking water source in Norway using hydrodynamic modelling

2018 ◽  
Author(s):  
Hadi Mohammed ◽  
Andreas Longva ◽  
Razak Seidu
Keyword(s):  
Drinking Water ◽  
Water Supply ◽  
Management Strategies ◽  
Fold Increase ◽  
Water Source ◽  
Water Supply Systems ◽  
Drinking Water Source ◽  
E Coli ◽  
Risk Management Strategies

Abstract. This study develops hydrodynamic and water quality models for long-term prediction of E. coli concentrations at the raw water intake point of lake Brusdalsvatnet in Norway. The study is based on previously observed concentrations of E. coli in the tributaries of the lake and local projections of precipitation and air temperature in the region. The results indicate a gradual rise in the temperature of water at the intake point from the base year (2017) through to year 2075. Shorter spring circulation and longer autumn circulation periods are expected in the lake in future. Concentrations of E. coli at the intake point of the lake are expected to marginally increase in future. By the year 2075, the models predict a 3 fold and 2 fold increase in E. coli concentrations respectively for the spring and autumn seasons compared to current levels. The results is expected to provide the water supply system managers of Ålesund with the information necessary for long term planning and decisions in the protection of the drinking water source. The method used here can also be applied to similar water supply systems for developing effective risk management strategies for recent and future scenarios.

MODIS observations of cyanobacterial risks in a eutrophic lake: Implications for long-term safety evaluation in drinking-water source

2017 ◽  
Vol 122 ◽  
pp. 455-470 ◽  
Author(s):  
Hongtao Duan ◽  
Min Tao ◽  
Steven Arthur Loiselle ◽  
Wei Zhao ◽  
Zhigang Cao ◽  
...  
Keyword(s):  
Drinking Water ◽  
Safety Evaluation ◽  
Water Source ◽  
Eutrophic Lake ◽  
Drinking Water Source

Global return flow ratio

2017 ◽  
Author(s):  
Chloé Meyer
Keyword(s):  
Drinking Water ◽  
Water Source ◽  
Return Flow ◽  
Drinking Water Source ◽  
Chemical Contamination ◽  
Flow Ratio ◽  
Piped Water ◽  
Dug Wells

Population using an improved drinking water source (piped water into dwellings, yards or plots; public taps or standpipes; boreholes or tubewells; protected dug wells; or protected springs and rainwater) that is located on premises and available when needed and which is free of faecal and priority chemical contamination. Basin Pollution Quality Waste

scholarly journals Spatio-temporal Variation in Nutrient Profiles and Exchange Fluxes at the Sediment-Water Interface in Yuqiao Reservoir, China

2019 ◽  
Vol 16 (17) ◽  
pp. 3071 ◽  
Author(s):  
Wen ◽  
Wu ◽  
Yang ◽  
Jiang ◽  
Zhong
Keyword(s):  
Pore Water ◽  
Water Source ◽  
Water Soluble ◽  
Drinking Water Source ◽  
Eutrophic Lakes ◽  
Overlying Water ◽  
Total N ◽  
Yuqiao Reservoir ◽  
Nutrient Profiles ◽  
Main Component

Nutrients released from sediments have a significant influence on the water quality in eutrophic lakes and reservoirs. To clarify the internal nutrient load and provide reference for eutrophication control in Yuqiao Reservoir, a drinking water source reservoir in China, pore water profiles and sediment core incubation experiments were conducted. The nutrients in the water (soluble reactive P (SRP), nitrate-N (NO3−-N), nitrite-N (NO2−-N), and ammonium-N (NH4+-N)) and in the sediments (total N (TN), total P (TP) and total organic carbon (TOC)) were quantified. The results show that NH4+-N was the main component of inorganic N in the pore water. NH4+-N and SRP were higher in the pore water than in the overlying water, and the concentration gradient indicated a diffusion potential from the sediment to the overlying water. The NH4+-N, NO3−-N, and SRP fluxes showed significant differences amongst the seasons. The NH4+-N and SRP fluxes were significantly higher in the summer than in other seasons, while NO3−-N was higher in the autumn. The sediment generally acted as a source of NH4+-N and SRP and as a sink for NO3−-N and NO2−-N. The sediments release 1133.15 and 92.46 tons of N and P, respectively, to the overlying water each year.

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