The impact of watershed land use on maintaining acceptable quality influents for water treatment plants

2003 ◽  
Vol 52 (8) ◽  
pp. 587-596 ◽  
Author(s):  
Bilsen Beler Baykal ◽  
Aysegul Tanik ◽  
I. Ethem Gonenc
Keyword(s):  
Land Use ◽  
Water Treatment ◽  
Watershed Land Use ◽  
Water Treatment Plants ◽  
Acceptable Quality ◽  
The Impact

scholarly journals Cause of rapid monochloramine decay observed in treated water

2016 ◽  
Vol 17 (3) ◽  
pp. 752-758 ◽  
Author(s):  
Sam Hancock ◽  
Martin Harris ◽  
David Cook
Keyword(s):  
Water Treatment ◽  
Water Samples ◽  
Pilot Scale ◽  
The Other ◽  
Biological Degradation ◽  
Filter Media ◽  
Rapid Decay ◽  
Treated Water ◽  
Water Treatment Plants ◽  
The Impact

Rapid monochloramine decay has been observed in the product water of three River Murray water treatment plants (WTPs). Previous investigations identified that rapid monochloramine decay was microbiological in nature and observed in samples taken after media filtration but was absent in filtered water samples from a fourth WTP of similar design. The filters at the WTP not exhibiting rapid decay are backwashed with filtered non-disinfected water whereas the other WTPs backwash with treated chloraminated water. It was therefore hypothesised that backwashing filters with chloraminated water was the cause of the rapid monochloramine decay. A pilot-scale study was conducted to investigate the impact of backwashing with chloraminated water on the occurrence of microbiologically accelerated monochloramine decay. Additional samples were analysed to assess the impact of chloraminated backwash water on N-Nitrosodimethylamine (NDMA) formation and biological degradation of taste and odour compounds 2-methyl isoborneol (MIB) and geosmin in the filter media. Backwashing with chloraminated filtered water was concluded to be the cause of the observed rapid monochloramine decay, with rapid decay observed within 8 weeks for the filters backwashing with chloramines. Additionally, backwashing with chloraminated filtered water was observed to increase NDMA formation and impair the biological degradation performance of MIB and geosmin.

Characterization and destabilization of spent filter backwash water particles

2002 ◽  
Vol 2 (2) ◽  
pp. 115-122 ◽  
Author(s):  
A. Adin ◽  
L. Dean ◽  
F. Bonner ◽  
A. Nasser ◽  
Z. Huberman
Keyword(s):  
Water Treatment ◽  
Chemical Characterization ◽  
Physical Parameters ◽  
Ph Measurements ◽  
Particle Count ◽  
Water Treatment Plants ◽  
Physical Chemical ◽  
Organic Particles ◽  
The Impact

Inorganic and organic particles, including bacteria, viruses and parasites, which are retained within a granular filter during surface water filtration, are removed by backwashing the filter with clean water or water and air. The objective of the study was to characterize SFBW and determine its treatability by coagulation. Microbial and physical-chemical characterization of SFBW collected from a number of different water treatment plants was performed. Experiments to determine the impact of coagulation/flocculation on the SFBW samples were also conducted. SFBW was collected from six different water treatment plants and analyzed for microbial and physical parameters. Physical characterization was done on SFBW collected from all of the treatment plants. Turbidity and pH measurements were taken over the course of the backwash run, and the backwash samples were collected in two to four 20 L containers. A number of parameters were measured for the samples in each container, as well as for SFBW composites made by mixing equal portions of the container contents. The measured parameters included: turbidity, pH, TSS, DOC, UV-254 and alkalinity. Jar tests were carried out on individual containers, on SFBW composite and on SFBW composite that was allowed to settle for one hour. Turbidity and particle count data was collected for both settled and filtered samples.

Effect of Forest Cover on Water Treatment Costs

2017 ◽  
Vol 03 (04) ◽  
pp. 1750006 ◽  
Author(s):  
Travis Warziniack ◽  
Chi Ho Sham ◽  
Robert Morgan ◽  
Yasha Feferholtz
Keyword(s):  
Water Quality ◽  
Land Use ◽  
Water Treatment ◽  
Forest Cover ◽  
The United States ◽  
Economic Benefits ◽  
Treatment Costs ◽  
Quality Data ◽  
Water Quality Data ◽  
The Impact

This paper studies the relationship between forest cover and drinking water chemical treatment costs using land use data and a survey by the American Water Works Association (AWWA). The survey gathers cost and water quality data from 37 treatment plants in forested ecoregions of the United States. We model the effect of forest conversion on the cost of water treatment using a two-step process. First, we examine the effect of changes in land use on water quality through an ecological production function. Second, we examine the effect of changes in water quality on cost of treatment through an economic benefits function. We find a negative relationship between forest cover and turbidity, but no relationship between forest cover and total organic carbon (TOC). Increasing forest cover in a watershed by 1% reduces turbidity by 3%, and increasing development by 1% in a watershed increases turbidity by 3%. The impact of development is more consistent across models than the impact of forest cover. We also find a large impact on turbidity from grazing in the watershed. Our economic benefits function shows a 1% increase in turbidity increases water treatment costs by 0.19%, and 1% increase in TOC increases water treatment costs by 0.46%. TOC has a clearer impact on costs than turbidity, which becomes insignificant when we omit one of our observations with high turbidity.

scholarly journals Assessing the impact of watershed land use on Kebena river water quality in Addis Ababa, Ethiopia

2021 ◽  
Vol 10 (1) ◽  
Author(s):  
Kalkidan Asnake ◽  
Hailu Worku ◽  
Mekuria Argaw
Keyword(s):  
Water Quality ◽  
Land Use ◽  
River Water ◽  
Land Use Planning ◽  
Addis Ababa ◽  
Surface Water Quality ◽  
Wet Season ◽  
Watershed Land Use ◽  
Land Use Types ◽  
The Impact

Abstract Background The impact of watershed land-use on surface water quality is one of the under researched areas in mega cities of the developing countries like Addis Ababa. The study examined the impact of watershed land uses on the Kebena river water quality within its seasonal and spatial variation and assessed the relationship between river water pollution and dominant land-use types in the sub-watersheds. Method The main land use types in the sub-watersheds were digitized from aerial photograph of 2016, and quantified for water quality impact analysis. Water samples were collected from the main Kebena river and the three sub-watersheds source and outlet points. A total of 128 samples were collected during the dry and wet seasons of 2016 and 2017 and analyzed for various water quality parameters. The study employed ANOVA, independent t-tests and multiple regression analysis to examine variations in water quality and assess the influence of the different land uses on water quality. Results Forest, built-up area and cultivated lands are the three major land use types in the Kebena watershed accounting for 39.14, 32.51 and 27.25% of the total area, respectively. Kebena catchment is drained by three sub-watersheds namely, Denkaka (44.9% cultivated land), Little-Kebena (60.87% forested) and Ginfle (90.44% urban land). The concentration of pollutants in the Kebena river was significantly higher (P < 0.001) in the dry season than in the wet season. However, when compared to surface water quality standards, both the dry and wet season water quality records are exceptionally high. The urban and forest dominated sub-watersheds contribute significantly high amount of (P < 0.001) pollutant loads to the river which is associated with high runoff from impervious surfaces and sewerage discharge to the river from nearby urban settlements. Conclusion Integrating watershed planning with land use planning is of paramount importance to address water quality problems in urban areas. Thus, in the urban dominated sub-catchment, land-use planning should aim to relocating river front communities, providing sufficient river buffer-zones and forwarding appropriate storm water management schemes. In the forested sub-catchment, planning should protect, retain and enhance the existing natural green spaces through open space planning, and management schemes while providing wide river-buffer with natural vegetation cover to minimize pollution load to urban rivers from agriculture dominated sub-watershed.

scholarly journals  the Impact of Watershed Land Use on River Water Quality: Implication for Planning in the Case of Kebena River Watershed, Addis Ababa, Ethiopia

2020 ◽  
Author(s):  
Kalkidan Asnake ◽  
Hailu Worku ◽  
Mekuria Argaw
Keyword(s):  
Water Quality ◽  
Land Use ◽  
Surface Water Quality ◽  
Quality Parameters ◽  
Cultivated Land ◽  
Water Quality Indicators ◽  
Watershed Land Use ◽  
Land Use Types ◽  
Management Schemes ◽  
The Impact

Abstract Background: The impact of watershed land-use on surface water quality, especially in urbanized areas, has been investigated in numerous studies in developed countries, however, the issue is one of the under researched areas in developing cities of Africa. To study the impact of watershed land-use on surface water quality, we used the main land use types of the Kebena watershed from aerial photograph and collected river water samples during the dry and wet seasons for two consecutive years at different points from the river course. We calculated the share of each land use using ArcGIS and tested the water quality during each season. The variations in water quality parameters relating to the different land use types of the sub-watersheds were analyzed using ANOVA. Results: Kebena watershed is mainly covered by 39.14% forest, 32.51% built-up area and 27.25% cultivated land. At sub-catchment level, Denkaka, (agriculture dominated) sub-catchment with 44.90 % cultivated land, Little Kebena, (forest dominated) sub-catchment, with 60.87% forest cover and Ginfle (urban dominated) sub-catchment with 90.44% built-up area were identified. The variations in water quality parameters relating to the different land use types of Kebena watershed revealed the significantly high seasonal relationship between the concentration of the water quality indicators during the dry season at (P<0.001, P<0.05). Furthermore, there is a strong positive relationship between the urban and forest dominated sub-catchments and water quality indicators during both the wet and dry seasons than agriculture dominated sub-catchment.Conclusion: Integrating watershed planning with land use planning, therefore, becomes one of the vital tools to address water quality problems in a holistic manner to further prioritize restoration and protection strategies for specific sub-catchments. Thus, in the urban dominated sub-catchment, relocating riverfront communities, providing a well-designed sewage system, applying appropriate storm water management schemes, are some of the important measures while providing wide river buffers with various vegetation cover are necessary to minimize pollutants influx to the river from the agriculture dominated sub-catchment. Furthermore, in the forested sub-catchment, applying preventive measures to retain and enhance connectivity of the existing natural green spaces through open space planning, development and management schemes is crucial.

scholarly journals NOM characterization and removal at six Southern African water treatment plants

2009 ◽  
Vol 2 (2) ◽  
pp. 231-257 ◽  
Author(s):  
J. Haarhoff ◽  
M. Kubare ◽  
B. Mamba ◽  
R. Krause ◽  
T. Nkambule ◽  
...  
Keyword(s):  
Water Treatment ◽  
Process Design ◽  
Distribution Systems ◽  
Water Distribution ◽  
Treatment Plant ◽  
Drinking Water Treatment ◽  
Organic Pollution ◽  
Process Selection ◽  
Water Treatment Plants ◽  
The Impact

Abstract. Organic pollution is a major concern during drinking water treatment. Major challenges attributed to organic pollution include the proliferation of pathogenic micro-organisms, prevalence of toxic and physiologically disruptive organic micropollutants, and quality deterioration in water distribution systems. A major component of organic pollution is natural organic matter (NOM). The operational mechanisms of most unit processes are well understood. However, their interaction with NOM is still the subject of scientific research. This paper takes the form of a metastudy to capture some of the experiences with NOM monitoring and analysis at a number of Southern African Water Treatment Plants. It is written from the perspective of practical process selection, to try and coax some pointers from the available data for the design of more detailed pilot work. NOM was tracked at six water treatment plants using dissolved organic carbon (DOC) measurements. Fractionation of the DOC based on biodegradability and molecular weight distribution was done at a water treatment plant in Namibia. A third fractionation technique using ion exchange resins was used to assess the impact of ozonation on DOC. DOC measurements alone did not give much insight into NOM evolution through the treatment train. The more detailed characterization techniques showed that different unit processes preferentially remove different NOM fractions. Therefore these techniques provide better information for process design and optimisation than the DOC measurement which is routinely done during full scale operation at these water treatment plants. Further work will focus on streamlining and improving the reproducibility of selected fractionation techniques, characterization of NOM from different water sources, and synthesis of the results into a systematic, practical guideline for process design and optimisation.

scholarly journals Simulating sediment discharge at water treatment plants under different land use scenarios using cascade modelling with an expert-based erosion-runoff model and a deep neural network

2021 ◽  
Vol 25 (12) ◽  
pp. 6223-6238
Author(s):  
Edouard Patault ◽  
Valentin Landemaine ◽  
Jérôme Ledun ◽  
Arnaud Soulignac ◽  
Matthieu Fournier ◽  
...  
Keyword(s):  
Neural Network ◽  
Land Use ◽  
Water Treatment ◽  
Deep Neural Network ◽  
Treatment Plant ◽  
Water Treatment Plant ◽  
Sediment Discharge ◽  
Farming Practices ◽  
Water Treatment Plants ◽  
Land Use Scenarios

Abstract. Excessive sediment discharge in karstic regions can be highly disruptive to water treatment plants. It is essential for catchment stakeholders and drinking water suppliers to limit the impact of high sediment loads on potable water supply, but their strategic choices must be based on simulations integrating surface and groundwater transfers and taking into account possible changes in land use. Karstic environments are particularly challenging as they face a lack of accurate physical descriptions for the modelling process, and they can be particularly complex to predict due to the non-linearity of the processes generating sediment discharge. The aim of the study was to assess the sediment discharge variability at a water treatment plant according to multiple realistic land use scenarios. To reach that goal, we developed a new cascade modelling approach with an erosion-runoff geographic information system (GIS) model (WaterSed) and a deep neural network. The model was used in the Radicatel hydrogeological catchment (106 km2 in Normandy, France), where karstic spring water is extracted to a water treatment plant. The sediment discharge was simulated for five design storms under current land use and compared to four land use scenarios (baseline, ploughing up of grassland, eco-engineering, best farming practices, and coupling of eco-engineering/best farming practices). Daily rainfall time series and WaterSed modelling outputs extracted at connected sinkholes (positive dye tracing) were used as input data for the deep neural network model. The model structure was found by a classical trial-and-error procedure, and the model was trained on 2 significant hydrologic years. Evaluation on a test set showed a good performance of the model (NSE = 0.82), and the application of a monthly backward-chaining nested cross-validation revealed that the model is able to generalize on new datasets. Simulations made for the four land use scenarios suggested that ploughing up 33 % of grasslands would increase sediment discharge at the water treatment plant by 5 % on average. By contrast, eco-engineering and best farming practices will significantly reduce sediment discharge at the water treatment plant (respectively in the ranges of 10 %–44 % and 24 %–61 %). The coupling of these two strategies is the most efficient since it affects the hydro-sedimentary production and transfer processes (decreasing sediment discharge from 40 % to 80 %). The cascade modelling approach developed in this study offers interesting opportunities for sediment discharge prediction at karstic springs or water treatment plants under multiple land use scenarios. It also provides robust decision-making tools for land use planning and drinking water suppliers.

scholarly journals NOM characterization and removal at six Southern African water treatment plants

2010 ◽  
Vol 3 (1) ◽  
pp. 53-61 ◽  
Author(s):  
J. Haarhoff ◽  
M. Kubare ◽  
B. Mamba ◽  
R. Krause ◽  
T. Nkambule ◽  
...  
Keyword(s):  
Water Treatment ◽  
Distribution Systems ◽  
Water Distribution ◽  
Treatment Plant ◽  
Drinking Water Treatment ◽  
Water Treatment Plant ◽  
Organic Pollution ◽  
Process Selection ◽  
Water Treatment Plants ◽  
The Impact

Abstract. Organic pollution is a major concern during drinking water treatment. Major challenges attributed to organic pollution include the proliferation of pathogenic micro-organisms, prevalence of toxic and physiologically disruptive organic micro-pollutants, and quality deterioration in water distribution systems. A major component of organic pollution is natural organic matter (NOM). The operational mechanisms of most unit processes are well understood. However, their interaction with NOM is still the subject of scientific research. This paper takes the form of a meta-study to capture some of the experiences with NOM monitoring and analysis at a number of Southern African Water Treatment Plants. It is written from the perspective of practical process selection, to try and coax some pointers from the available data for the design of more detailed pilot work. NOM was tracked at six water treatment plants using dissolved organic carbon (DOC) measurements. Fractionation of the DOC based on biodegradability and molecular weight distribution was done at a water treatment plant in Namibia. A third fractionation technique using ion exchange resins was used to assess the impact of ozonation on DOC. DOC measurements alone did not give much insight into NOM evolution through the treatment train. The more detailed characterization techniques showed that different unit processes preferentially remove different NOM fractions. Therefore these techniques provide better information for process design and optimisation than the DOC measurement which is routinely done during full scale operation at these water treatment plants.

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