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  • 1.
    Aullón Alcaine, Anna
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630), Environmental Geochemistry and Ecotechnology.
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630), Environmental Geochemistry and Ecotechnology.
    Jacks, Gunnar
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630), Environmental Geochemistry and Ecotechnology.
    Schulz, C.
    Universidad Nacional de la Pampa, Argentina.
    Bundschuh, Jochen
    University of Southern Queensland, Australia.
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630), Environmental Physics.
    Mörth, Carl-Magnus
    Stockholms Universitet, Institutionen för geologiska vetenskaper.
    Geogenic arsenic and fluoride in shallow aquifers of northeastern La Pampa, Argentina: mobility constraints2013Conference paper (Other academic)
    Abstract [en]

    High concentrations of geogenic arsenic (As) and fluoride (F-) in groundwater have been reported at elevated concentrations in different parts of the Chaco-Pampean Plain, in Argentina, where more than 2 million people may be exposed to high levels of these toxic elements through drinking water. Groundwater from the shallow aquifer is far exceeding the permissible WHO Standard limits of 10 μg/L for As and 1.5 mg/L for fluoride, as well as the Argentinean Standard limit of 50 μg/L for As. Geogenic As results due to the weathering of ash originated by volcanic eruptions from the Andean Cordillera and transported by wind and deposited along with the sediments and also as discrete layers and lenses over large geographical area containing around 90% of rhyolitic glass. Groundwater is hosted in a sandy silty interconnected system of aquifers and aquitards within the The Pampean aquifer. A total of 44 groundwater samples were collected from the shallow aquifers in NE of La Pampa province. Two rural areas covering an area of 600km2 in Quemú Quemú (QQ) and 300km2 in Intendente Alvear (IA) were investigated in the present study. Groundwater was circum-neutral to alkaline (pH 7.43-9.18), predominantly oxidizing (Eh ~0.24 V) with widely variable EC range (456-11,400 μS/cm). The major cation dissolved in groundwater was Na+, while the predominant anions were HCO3-, Cl- and SO42-, respectively. Water type in QQ was mostly Na-HCO3- while in IA, the composition differed between Na-HCO3- and Na-Cl-SO42- water types. Groundwater composition showed high degree of mineralization and high salinity evidenced by high EC. In discharge areas, high evaporation rates result in high salinity of shallow groundwater and visible salts incrustations on the surface of the lakes. Elevated concentrations of NO3- and PO43- observed in some wells indicated possible anthropogenic contamination. Total As concentration in groundwater from QQ ranged from 5.58 to 535 μg/L, where 94% of the wells exceeded the WHO standard limit for safe drinking water of 10 μg/L, and 56% of the wells exceeded the old Argentine standard limit of 50 μg/L. F- concentrations revealed heterogeneity and high concentrations in some wells (0.5-14.2 mg/L), 78% of samples in QQ study area exceeded the WHO standard limit of 1.5 mg/L. Under oxidizing conditions and neutral to alkaline pH, arsenate (AsV) species predominated, mainly in HAsO42- forms. As "hotspots" indicated locally contamination and correlated positively with F-, HCO3-, B and V and showed negative correlation with salinity, dissolved Fe, Al and Mn. The mechanisms involved in the mobilization of As in the shallow aquifers are controlled by the rise of pH, variations in Eh conditions and the presence of competitor ions (HCO3-, PO43-, Si, V oxyanions). Geochemical processes like adsorption/desorption, precipitation/dissolution and redox reactions may trigger to As mobilization in the shallow aquifers of La Pampa region.

  • 2.
    Aullón Alcaine, Anna
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Sandhi, Arifin
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Jacks, Gunnar
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Bundschuh, Jochen
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Schulz, C.
    Mörth, C. M.
    Distribution and mobility of geogenic arsenic in the shallow aquifers of the northeast of La Pampa, Argentina2012In: Understanding the Geological and Medical Interface of Arsenic, As 2012 - 4th International Congress: Arsenic in the Environment, 2012, p. 132-134Conference paper (Refereed)
    Abstract [en]

    Groundwater contamination with elevated Arsenic (As) and other toxic trace elements has been studied in the central part of the vast Chaco-Pampean Plain, in the city of Quemú Quemú, northeastern La Pampa, Argentina. The groundwater samples were mostly alkaline with pH ranging up to 9.18, oxidizing and characterized by high EC. The concentration of total As (5.58-535 μg/L) and fluoride (0.5-14.2 mg/L) in some samples exceeded the recommended WHO drinking water guideline and the Argentine national drinking water standard. Arsenic was positively correlated with bicarbonate (HCO 3 -), Boron (B), Fluoride (F) and Vanadium (V). Long-term consumption of the groundwater could pose a severe health threat for the local community.

  • 3.
    Bhattacharya, Prosun
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Jacks, Gunnar
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering. International Groundwater Arsenic Research Group.
    von Brömssen, Mattias
    Department of Soil and Water Environment Ramböll Sweden AB.
    Targeting Arsenic-Safe Aquifers in Regions with High Arsenic Groundwater and its Worldwide Implications (TASA)2015Report (Other academic)
  • 4.
    Bundschuh, Jochen
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    von Brömssen, Mattias
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    Jakariya, Md
    Jacks, Gunnar
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Management and Assessment.
    Litter, M.I.
    Garcia, M.E.
    Arsenic-safe aquifers as a socially acceptable source of safe drinking water: What can rural Latin America learn from Bangladesh experiences?2009In: Natural Arsenic in Groundwater of Latin America: Occurrence, health impact and remediation, The Netherlands: CRC Press/Balkema , 2009, p. 677-685Chapter in book (Refereed)
  • 5.
    Engström, Emma
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Balfors, Berit
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Mörtberg, Ulla
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Gaily, Tarig
    Mangold, Mikael
    Prevalence of microbiological contaminants in groundwater sources and risk factor assessment in Juba, South Sudan2015In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 515-516, p. 181-187Article in journal (Refereed)
    Abstract [en]

    In low-income regions, drinking water is often derived from groundwater sources, which might spread diarrheal disease if they are microbiologically polluted. This study aimed to investigate the occurrence of fecal contamination in 147 improved groundwater sources in Juba, South Sudan and to assess potential contributing risk factors, based on bivariate statistical analysis. Thermotolerant coliforms (TTCs) were detected in 66% of the investigated sources, including 95 boreholes, breaching the health-based recommendations for drinking water. A significant association (p<. 0.05) was determined between the presence of TTCs and the depth of cumulative, long-term prior precipitation (both within the previous five days and within the past month). No such link was found to short-term rainfall, the presence of latrines or damages in the borehole apron. However, the risk factor analysis further suggested, to a lesser degree, that the local topography and on-site hygiene were additionally significant. In summary, the analysis indicated that an important contamination mechanism was fecal pollution of the contributing groundwater, which was unlikely due to the presence of latrines; instead, infiltration from contaminated surface water was more probable. The reduction in fecal sources in the environment in Juba is thus recommended, for example, through constructing latrines or designating protection areas near water sources. The study results contribute to the understanding of microbiological contamination of groundwater sources in areas with low incomes and high population densities, tropical climates and weathered basement complex environments, which are common in urban sub-Saharan Africa.

  • 6.
    Engström, Emma
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630), Environmental Management and Assessment.
    Balfors, Berit
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630), Environmental Management and Assessment.
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630), Environmental Management and Assessment.
    Modeling bacterial transport and removal in a constructed wetland system2010In: Proceedings of the COMSOL Conference, 2010, Paris, 2010Conference paper (Refereed)
  • 7.
    Engström, Emma
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Management and Assessment.
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Management and Assessment.
    Balfors, Berit
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Management and Assessment.
    Predicting the transport and fate of Escherichia coli in unsaturated sand filters2011In: Journal of Contaminant Hydrology, ISSN 0169-7722, E-ISSN 1873-6009Article in journal (Other academic)
  • 8.
    Engström, Emma
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Kulabako, Robina
    Makerere University, Department of Civil Engineering, Kampala, Uganda.
    Balfors, Berit
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Water Transport, Retention, and Survival of Escherichia coli in Unsaturated Porous Media: A Comprehensive Review of Processes, Models, and Factors2015In: Critical reviews in environmental science and technology, ISSN 1064-3389, E-ISSN 1547-6537, Vol. 45, no 1Article, review/survey (Refereed)
    Abstract [en]

    The vadose zone can function as both a filter and a passage for bacteria. This review evaluates when and why either effect will apply based on available literature. It summarizes theories and experimental research that address the related, underlying bacterial attenuation processes, the applied macro-scale modeling approaches, and the influencing factors - including the cell, soil, solution and system characteristics. Results point to that the relative importance of each removal mechanism depends on the moisture content and the solution ionic strength. The limitations of available modeling approaches are discussed. It remains unclear in which contexts these are reliable for predictions. The temporal first-order kinetic Escherichia coli (E. coli) removal coefficient ranges three orders of magnitude, from 10(-4) to 10(-1)/min. Results suggest that this rate depends on the pore-water velocity. Spatial filtration of E. coli increases with slower flow and higher collector surface heterogeneity. It could be insignificant in the case of heavy and sudden infiltration and subsequent transport in preferential flow paths, induced, for example, by plant roots or cracks in clayey soils. Future research thus needs to address transport as an effect of extreme weather events such as droughts and subsequent floods.

  • 9.
    Engström, Emma
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630), Environmental Management and Assessment.
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630), Environmental Management and Assessment.
    Kulabako, Robinah
    Department of Civil Engineering, Makerere University, Kampala, Uganda.
    Balfors, Berit
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630), Environmental Management and Assessment.
    Escherichia coli transport and fate in unsaturated porous media: a literature review of experimental findings and theories relating to processes, models and influencing factors2011In: Critical reviews in environmental science and technology, ISSN 1064-3389, E-ISSN 1547-6537Article in journal (Other academic)
  • 10.
    Hamisi, Rajabu
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Balfors, Berit
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Jansson, Per-Erik
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Hamerlynck, O
    Duvail, S
    Applications of Process Base Models for Sustainable Water Utilizations in a Competing Demands and Climate Variability: A Case of the Lower Rufiji, Tanzania2013Conference paper (Refereed)
  • 11.
    Hamisi, Rajabu
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering. SEED-KTH.
    Renman, Gunno
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering. SEED-KTH.
    Brokking Balfors, Berit
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering. SEED-KTH.
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering. SEED-KTH.
    A new modelling approach for phosphorus mobility and retention processes in the Oxundaån catchment, SwedenManuscript (preprint) (Other academic)
    Abstract [en]

    Eutrophication is the most significant threat towater quality in the entire Baltic Sea region. Its causes are nutrientover-enrichment from diffuse and point sources. Thematic strategies forsustainable mitigation of phosphorus loss from sewage drainage systems andrunoffs from arable land require a holistic approach to identify the criticalpolluting sources and implement relevant policy for adaptive water qualitymanagement. The use of constructed wetlands constitutes one such strategy thatcan mitigate phosphorus loss. However, insufficient understanding about phosphorusmobility and retention in catchments significantly hinders efforts to identifysuitable sites for constructed wetlands and implement alternative, adaptive andeffective management actions. This study aims to evaluate the long-termphosphorus mobility and retention in the Oxudaån catchment in Sweden, andthereby propose suitable sites to localize constructed wetlands. The Soil andWater Assessment watershed model was applied to map and quantify the phosphorusloading from diffuse and point sources under the scenarios of land usemanagement practices. Simulation results have demonstrated the positivecorrelation between the phosphorus concentration with the surface runoffs andnegative correlation with the pH. Overall, Oxundaån catchment indicates a decreasingtrend of phosphorus loading in the Verkaån and Oxundaån riverine of around 2.1% and 1.3 % per year, respectively. The present study suggests the suitablesites for localizing constructed wetlands in the south-west and north-east ofOxundaån lake based on the factor of low slope topography and soilpermeability. The simulation results from the SWAT model offer evidence thatcan guide the localization and choice of management interventions to achieve asustainable mitigation of phosphorus loss. This study concludes that, while singlemanagement actions can help solve the problem of eutrophication, a moreeffective and sustainable mitigation of eutrophication will require the integrationof multiple adaptive land use management approaches.

  • 12.
    Hamisi, Rajabu
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering. SEED-KTH.
    Renman, Gunno
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering. SEED-KTH.
    Herrmann, Inga
    Department of Civil, Environmental and Natural Resources Engineering.
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering. SEED-KTH.
    Reactive transport modelling of long-term phosphorus dynamic in the compact constructed   wetland using COMSOL MultiphysicsIn: Ecological Engineering JournalArticle in journal (Other academic)
    Abstract [en]

    A three-dimensional reactive transport model (RETRAP-3D) was developed by this study in the COMSOL Multiphysics®software to evaluate the long-term sorption capacity and mechanisms of dissolved reactive phosphorus removal in reactive adsorbent. The model coupledphysics interfaces for water flow, transport of reactive species, reaction kinetics for chemical compositions and biofilm development. Simulations were conducted for Polonite®, Filtralite P®, and Blast Furnace Slag mediaat fully saturated media, equilibrium miscible solution and isothermal heat transfer conditions. The model was validated using column experimental data ofsimilar media for application in constructed filter beds. The general modelling results showed good agreement with the measured breakthrough data. The most significant DIP retention capacity (P < 0.02) and longest residence time(1250 days) has been found for Polonite® and the most insignificant DIP retention for blast furnace slag (P > 0.54). The DIP removal was significantly correlated to factors of pH change, media characteristics, hydraulic dosage and retention times. These results demonstrate the reliability of the model as aflexible tool to predict the long-term performance of filter media and better understand processes within the system under various operational, weather and wastewater conditions.

  • 13. Hossain, M.
    et al.
    Mainul Islam, M.
    Rashid, S. M. A.
    Moklesur Rahman, M.
    Rahman, M.
    Sultana, S.
    Ahmed, K. M.
    Aziz Hasan, M.
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630).
    Jacks, Gunnar
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630).
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630).
    Von Brömssen, M.
    Delimiting the shallow aquifer characteristics using Vertical Electric Soundings (VES) and hydrochemical variability in a region with high arsenic groundwater in southeastern Bangladesh2010In: Arsenic in Geosphere and Human Diseases, As 2010 - 3rd International Congress: Arsenic in the Environment, 2010, p. 105-107Conference paper (Refereed)
  • 14.
    Kizito, Frank
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Djuraboev, Djamshid
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Akol, Gilbert
    Mugisha, Feriha
    Ngirane-Katashaya, Gaddi
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    A web-based Customer Account Management portal for an urban water utility in UgandaManuscript (preprint) (Other academic)
    Abstract [en]

    The Kampala Water Supply Service Area (KWSSA) is one of twenty-two urban centres managed by theNational Water and Sewerage Corporation (NWSC), a public utility owned by the Government of Uganda. Owing to the size of the city and the scope of operations, management of KWSSA is decentralized to eleven administrative units referred to as Branches, which in turn are further subdivided into smaller geographical units, called Territories.

    “Territorial Management”, a concept practiced within KWSSA, involves sub-division of the area ofoperation of a utility into geographical units small enough for a designated individual, the TerritorialManager (TM), to gain a personal knowledge of, and greater contact with, the customers within hisjurisdiction. This closer focus should, in principle, enable the TM to better control aspects of water sales and revenue collection within his territory, and at the same time make him more directly accountable forits performance relative to that of the company as a whole. Proper territorial management should act bothas an incentive for competition amongst territories (leading to global performance gains) and a basis forreward of exceptional achievers.

    This paper describes the establishment of a web portal providing an integration framework for various GIS tools and services designed to support territorial customer account management within KWSSA. Inthe paper, a geodatabase has been established for a selected “Model Branch”, and a set of prototype webmappingapplications designed and implemented. These tools provide functionality for tracking the connection status of individual customers, their consumption and payment histories, as well as complaints received from the customers. The various tools have been brought together within a single vertical webportal, which also provides links to other kinds of information as well as customized content aggregations(mash-ups) relating to the organization.

  • 15.
    Kizito, Frank
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Mugisha, Feriha
    Ameda, Emmanuel
    Kamanyi, Joseph
    Ngirane-Katashaya, Gaddi
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Hydraulic modelling as a tool for problem analysis and decision support: Case study of the Naguru water supply system in UgandaIn: Journal of Hydroinformatics, ISSN 1464-7141, E-ISSN 1465-1734Article in journal (Other academic)
    Abstract [en]

    This paper describes a study in which hydraulic modeling was applied as a tool to guide planningand decision-making to address water distribution bottlenecks within an urban water supplysystem in Uganda. In response to chronic supply intermittencies and an ever-increasing outcryfrom affected customers, a number of interventions were proposed - and some implemented -formulated largely based on intuition, rule-of-thumb, and experience of the network operationalstaff. However, in recognition of the constraints of this approach in the face of an increasinglycomplex and ever-expanding network, a more rigorous and scientific approach was applied, inwhich simulation modeling was used to evaluate system performance under the various proposed interventions. Model results indicated that most of the proposed alternatives, including those thathad already been implemented, would yield unsatisfactory performance in the medium to longterm, albeit providing minimal relief in the short term. The study thus demonstrated the importance of application of formal tools such as hydraulic modeling as a replacement for moreintuitive and judgment-based network management approaches, especially given the large,complex and problem-prone water supply systems characteristic of urban utilities in developingcountries.

  • 16.
    Kizito, Frank
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Management and Assessment.
    Mutikanga, Harrison
    Ngirane-Katashaya, Gaddi
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Management and Assessment.
    Development of decision support tools for decentralised urban water supply management in Uganda: An action research approach2009In: Computers, Environment and Urban Systems, ISSN 0198-9715, E-ISSN 1873-7587, Vol. 33, no 2, p. 122-137Article in journal (Refereed)
    Abstract [en]

    This paper presents a study in which four real-life problem situations are used to explore the challenges of developing and implementing decision support tools within air urban water utility. In the Study, all Action Research approach is used. with theoretical considerations leading to specific actions being implemented, which ill turn yield results that are used to reflect upon the original theoretical assumptions. Results of the study emphasize the need for proper problem-structuring prior to the formulation of actions, the challenges of moving from planning to action; the importance of User involvement in the development of tools; and how a good match of people, problem-structuring, proactiveness and participatory tools development is required for effective decision support provision. The study also highlights the challenges of embedding decision support within existing work systems ill organizations. The Action Research approach is shown to be useful in bridging the gap between theory and practice, aiding the development of decision Support tools of immediate and practical benefit to organizations.

  • 17.
    Kizito, Frank
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Ngirane-Katashaya, Gaddi
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Bridging the gap between academic research and technological practice: Roles, benefits and pitfalls of action research in information systems developmentManuscript (Other academic)
    Abstract [en]

    This paper highlights the shortfalls of traditional approaches to academic research in the technological sciences, with respect to their failure to effectively impact on practice and tosupport joint learning between academicians and practitioners. Action Research (AR) is proposedas a suitable way of bridging this gap. AR is an inquiry process that involves partnership between researchers and practitioners for the purpose of addressing a real life problem issue, while simultaneously generating scientific knowledge. It is recognized that AR methods provide apotential avenue to improve the practical relevance of Information Systems (IS) research. An ARapproach has been used in an ongoing study involving the development of Decision SupportSystems (DSS) for water supply management in Uganda. The study seeks to explore how thedegree of adoption of DSS in practice, generally perceived to be low, may be improved.However, AR is not without its challenges, many of which are both contextual and emergent innature, and these are highlighted in the paper. The case study thus provides an opportunity, notonly to carry out research specific to the particular field of study (IS development), but also to reflect on the roles, benefits and pitfalls of AR as a research approach.

  • 18.
    Kizito, Frank
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Ngirane-Katashaya, Gaddi
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Exploring “commercial” water losses in an urban water supply system in Uganda: A geostatistical modeling approach2008In: Applied Spatial Analysis and Policy, ISSN 1874-463XArticle in journal (Other academic)
    Abstract [en]

    Like many urban water utilities, Kampala Water (KW) in Uganda has faced challenges in dealing with Non-Revenue Water, defined as the difference between water produced and water sold. One particular challenge has been in quantifying and localizing the “apparent” or “commercial” losses fraction of the water balance relating to the KW service area. This paper presents a study in which geostatistical modelling was used to investigate the possible causes of stagnation in watersales volumes within a selected part of the KW service area, despite continued growth in thecustomer base resulting from connection of new customers. In the study, a variogram model ofwater sales volumes was established. This model was then used to predict water sales volumes ona raster grid throughout the study area. The predicted volumes were compared with actual watersales for a selected period, and a difference map was generated. Subsequently, post plots of thelocations of various reported field anomalies (aged and defective meters, water supplyinsufficiencies, leaks, illegal consumption, disconnected accounts, and accounts billed onestimated consumption) were overlaid in turn on the difference map of water sales volumes.These map overlays were used to explore the spatial correlations between the prevalence of thedifferent categories of field anomalies and occurrences of large differences between actual andpredicted water sales volumes. The comparisons served to highlight the locations and possiblecauses of significant drops in water sales volumes. Through the study, a geostatistical analysis toolwas developed consisting of computer code written using R, an open-source statistical computingand graphics language and environment. This tool will be incorporated as a module within aspatial decision support system prototype being developed for the KW service area.

  • 19.
    Kizito, Frank
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Management and Assessment.
    Ngirane-Katashaya, Gaddi
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Management and Assessment.
    Using geovisualisation to support participatory problem structuring and decision making for an urban water utility in Uganda2008In: Applied GIS, ISSN 1832-5505, Vol. 4, no 2, p. 1-33Article in journal (Refereed)
    Abstract [en]

    This paper describes the application of geovisualisation to facilitate participatory identification and structuring of problems in an urban water supply system in Uganda. The city of Kampala has experienced rapid expansion over the years, with a corresponding increase inthe demand for piped water supply. However, this demand was not well matched with expansion of the water supply system, and as a result parts of the city have been facingchronic supply anomalies and insufficiencies. Faced with the task of identifying remedies to theproblems in the system, the city water company undertook a formal participatory problemstructuring and decision analysis process, to try and understand the underlying causes of system failures as well as the geospatial patterns of these failures. As part of this process,analysis, mapping and geovisualisation of data derived from historical records of waterconsumption, as well as records of pipe breakages, supply intermittences, and other recordedcustomer complaints, was done. The maps so produced were key in bringing the variousstakeholders and decision makers to a common understanding of the problem issues, andhelped in the formulation of alternative courses of action. Furthermore, with the establishment of a formal discussion forum for problem analysis and decision making, structured participatory decision making was entrenched within the company’s work ethos. It is hoped that in future,the coupling of the geovisualisation tools with the existing operational databases in thecompany will result in the development of a functional spatial decision support system and adynamic framework for system performance monitoring and reliability assessment.

  • 20.
    Kizito, Frank
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Ngirane-Katashaya, Gaddi
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    When Action Plans Yield No Actions: Challenges of ImplementingNon-Revenue Water Reduction Strategies in an Urban Water Utilityin UgandaManuscript (preprint) (Other academic)
    Abstract [en]

    The classical approach to water loss management in a piped water supply system is to gain anunderstanding of the underlying factors contributing to losses, both physical and non-physical,within the system, and there after to formulate and implement strategies and actions aimed attackling these underlying causes. However, undertaking extensive root-cause analysis, and generating detailed Action Plans as an output of this process, does not in itself guaranteeeffective redress in the face of high system losses, nor do detailed Action Plans automatically translate into effective remedial actions. Based on experiences within a real-life organization, this paper explores the challenge of moving from planning to action and from problem analysis to theeffective implementation of identified solutions, and a number of prerequisites to achieving this end are proposed.

  • 21.
    Kulabako, N. R.
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Management and Assessment.
    Nalubega, M.
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Management and Assessment.
    Phosphorus transport in shallow groundwater in peri-urban Kampala, Uganda: results from field and laboratory measurements2008In: Environmental Geology, ISSN 0943-0105, E-ISSN 1432-0495, Vol. 53, no 7, p. 1535-1551Article in journal (Refereed)
    Abstract [en]

    To understand Phosphorus (P) sources and transport processes in the subsurface in Bwaise III Parish, Kampala, P attenuation and adsorption capacities of soils were studied in situ and from laboratory measurements. Relationships between sorption parameters and soil matrix properties, rates and mechanism of the adsorption process and soil P fractions were also investigated. P was generally higher in the wet than the dry season, but for both seasons, the maximum was 5 mgP/l. P transport mechanisms appeared to be a combination of adsorption, precipitation, leaching from the soil media and by colloids with the latter two playing an important role in the wet season. The sorption process comprised two phases with the first stage rate constants being about fourfold those of the second stage. The Langmuir isotherm described the sorption data well (R-2 >= 0.95) with the second soil layer exhibiting the highest sorption maximum (C-max) (average value 0.6 +/- 0.17 mgP/gDW). The best prediction of C-max had organic carbon, Ca, available P and soil pH. Residual P consisting mostly of organics was the main fraction in all the layers followed by inorganic HCl-P and NaOH-P in the top and middle layers, respectively. Loosely bound P (NH4Cl-P) was the least fraction (< 0.4% of total P) in all layers indicating the high binding capacity of P by the soils. The study results suggest that P dynamics is related to Ca, Fe and organic carbon content of the soils.

  • 22.
    Kulabako, N. R.
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Management and Assessment.
    Nalubega, M.
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Management and Assessment.
    Study of the impact of land use and hydrogeological settings on the shallow groundwater quality in a peri-urban area of Kampala, Uganda2007In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 381, no 03-jan, p. 180-199Article in journal (Refereed)
    Abstract [en]

    A study to assess the impacts of land use and hydrogeological characteristics on the shallow groundwater in one of Kampala's peri-urban areas (Bwaise III Parish) was undertaken for a period of 19 months. Water quality monitoring was carried out for 16 installed wells and one operational protected spring to ascertain the seasonal variation. The aspects of hydrogeological setting investigated in the study were the subsurface unconsolidated material characteristics (stratigraphy, lithology, hydraulic conductivity, porosity and chemical content), seasonal groundwater depths and spring discharge, topography and rainfall of the area. Both laboratory and field measurements were carried out to determine the soil and water characteristics. Field surveys were also undertaken to identify and locate the various land use activities that may potentially pollute. The results demonstrate that the water table in the area responds rapidly to short rains (48 h) due to the pervious (10(-5)-10(-3) ms(-1)) and shallow (< 1 mbgl) vadose zone, which consists of foreign material (due to reclamation). This anthropogenically influenced vadose zone has a limited contaminant attenuation capacity resulting in water quality deterioration following the rains. There is widespread contamination of the groundwater with high organic (up to 370 mgTKN/l and 779 mgNO(3)(-)/l), thermotolerant coliforms (TTCs) and faecal streptococci (FS) (median values as high as 126E3 cfu/100 ml and 154E3 cfu/100 ml respectively) and total phosphorus (up to 13 mg/l) levels originating from multiple sources of contamination. These include animal rearing, solid waste dumping, pit latrine construction and greywater/stormwater disposal in unlined channels leading to increased localised microbial (faecal) and organic (TKNNO3-) contamination during the rains. The spring discharge (range 1.22-1.48 m(3)/h) with high nitrate levels (median values of 117 and 129 mg/l in the wet and dry seasons) did not vary significantly with season (p=0.087) suggesting that this source is fed by regional base flow. However, the microbial quality deterioration observed in the spring discharge after a rain event (median values of 815TTCs cftr/100ml and 433 FS cfa/100ml) was attributed to the poor maintenance of the protection structure. Identification and selection of appropriate management solutions for the protection of shallow groundwater in informal settlements should not only be based on water quality problems and the causal physical characteristics as demonstrated by this study, but also institutional and socio-economic factors.

  • 23. Kulabako, R. N.
    et al.
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Nalubega, M.
    Soutter, L. A.
    Numerical modeling for preliminary assessment of natural remediation of phosphorus in variably saturated soil in a peri-urban settlement in Kampala, Uganda2011In: Geochemical Modeling of Groundwater, Vadose and Geothermal Systems, CRC Press , 2011, p. 267-283Chapter in book (Other academic)
    Abstract [en]

    The limited financial and technological resources available to clean polluted aquifers particularly in the developing countries such as in Sub-Saharan Africa where degradation of groundwater is recognized as one of the most serious water resources problem implies that contamination of groundwater resources remains a growing public health hazard (Xu and Usher, 2006). In this case, natural attenuation (or monitored natural attenuation-MNA) appears to be a possible contaminated land management option necessitating investigation. Attenuation is generally most effective in the unsaturated (vadose) zone. 

  • 24.
    Kulabako, Robinah N.
    et al.
    KTH, Superseded Departments, Land and Water Resources Engineering. KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Management and Assessment.
    Nalubega, Mai
    Thunvik, Roger
    KTH, Superseded Departments, Land and Water Resources Engineering. KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Management and Assessment.
    Characterization of peri-urban anthropogenic pollution in Kampala, Uganda2004In: WEDC International Conference on people centred approaches to water and environmental sanitation, 2004, p. 474-482Conference paper (Refereed)
  • 25.
    Kulabako, Robinah Nakawunde
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Management and Assessment.
    Nalubega, Maimuna
    Wozei, Eleanor
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Management and Assessment.
    Environmental health practices, constraints and possible interventions in peri-urban settlements in developing countries - a review of Kampala, Uganda2010In: International Journal of Environmental Health Research, ISSN 0960-3123, E-ISSN 1369-1619, Vol. 20, no 4, p. 231-257Article in journal (Refereed)
    Abstract [en]

    Like most cities in developing countries, Uganda's capital city, Kampala, is experiencing urbanisation leading to an increase in population, and rapid development of peri-urban (informal) settlements. More than 60% of the city's population resides in these settlements which have the lowest basic service levels (sanitation, water supply, solid waste collection, stormwater and greywater disposal). A review of earlier studies on infrastructure development and sustainability within Kampala's peri-urban settlements, field surveys in a typical peri-urban settlement in the city (Bwaise III Parish), and structured interviews with key personnel from the National Water and Sewerage Corporation (NWSC), Kampala City Council (KCC), and the National Environment Management Authority (NEMA) were undertaken. Findings on current environmental health practices as well as perspectives of local communities and interviewed institutions on problems, constraints and possible solutions to basic service provision are presented. The implications of these viewpoints for possible environmental health interventions are presented.

  • 26. Kulabako, Robinah
    et al.
    Nalubega, Mai
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Shallow groundwater quality in peri-urban KampalaIn: Water Science and Technology, ISSN 0273-1223, E-ISSN 1996-9732Article in journal (Other academic)
  • 27. Kulabako, Robinah
    et al.
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Management and Assessment.
    Nalubega, M.
    Soutter, A. L.
    Using field measurements and solute transport modelling to assess potential for natural remediation of phosphorus in variably staturated soil in a peri-urban settlement in Kampala, UgandaArticle in journal (Other academic)
  • 28.
    Kulabako, Robinah
    et al.
    Makerere University.
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Nalubega, Mai
    Soutter, A. L.
    Hydrodynamic modelling of subsurface flow and contaminant transport in a Peri-urban settlement in KampalaIn: Journal of Contaminant Hydrology, ISSN 0169-7722, E-ISSN 1873-6009Article in journal (Other academic)
  • 29.
    Kulabako, Robinah
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Management and Assessment.
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Management and Assessment.
    Soutter, L. A.
    Nalubega, M.
    Modelling of flow and phosphorus transport in variably saturated soil in a peri-urban settlement in Kampala, UgandaArticle in journal (Other academic)
  • 30. Kumar, Manish
    et al.
    Kumar, Pankaj
    Ramanathan, A. L.
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Management and Assessment.
    Singh, Umesh K.
    Tsujimura, M.
    Sracek, Ondra
    Arsenic enrichment in groundwater in the middle Gangetic Plain of Ghazipur District in Uttar Pradesh, India2010In: Journal of Geochemical Exploration, ISSN 0375-6742, E-ISSN 1879-1689, Vol. 105, no 3, p. 83-94Article in journal (Refereed)
    Abstract [en]

    Groundwater with high geogenic arsenic (As) is extensively present in the Holocene alluvial aquifers of Ghazipur District in the middle Gangetic Plain, India. A shift in the climatic conditions, weathering of carbonate and silicate minerals, surface water interactions, ion exchange, redox processes, and anthropogenic activities are responsible for high concentrations of cations, anions and As in the groundwater. The spatial and temporal variations for As concentrations were greater in the pre-monsoon (6.4-259.5 mu g/L) when compared to the post-monsoon period (5.1-205.5 mu g/L). The As enrichment was encountered in the sampling sites that were close to the Ganges River (i.e. south and southeast part of Ghazipur district). The depth profile of As revealed that low concentrations of NO3- are associated with high concentration of As and that As depleted with increasing depth. The poor relationship between As and Fe indicates the As release into the groundwater, depends on several processes such as mineral weathering, O-2 consumption, and NO3- reduction and is de-coupled from Fe cycling. Correlation matrix and factor analysis were used to identify various factors influencing the gradual As enrichment in the middle Gangetic Plain. Groundwater is generally supersaturated with respect to calcite and dolomite in post-monsoon period, but not in pre-monsoon period. Saturation in both periods is reached for crystalline Fe phases such as goethite, but not with respect to poorly crystalline Fe phases and any As-bearing phase. The results indicate release of arsenic in redox processes in dry period and dilution of arsenic concentration by recharge during monsoon. Increased concentrations of bicarbonate after monsoon are caused by intense flushing of unsaturated zone, where CO2 is formed by decomposition of organic matter and reactions with carbonate minerals in solid phase. The present study is vital considering the fact that groundwater is an exclusive source of drinking water in the region which not only makes situation alarming but also calls for the immediate attention.

  • 31. Mahanta, C.
    et al.
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630).
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630).
    Jacks, Gunnar
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630).
    Sracek, O.
    Nickson, R. T.
    Enmark, G.
    Norborg, D.
    Herbert, R.
    Groundwater arsenic in the Holocene Brahmaputra floodplains of Assam, Northeastern India: Distribution and trends of hydrogeochemical variations2010In: Arsenic in Geosphere and Human Diseases, As 2010 - 3rd International Congress: Arsenic in the Environment, 2010, p. 21-22Conference paper (Refereed)
  • 32. Maity, Jyoti Prakash
    et al.
    Nath, Bibhash
    Chen, Chien-Yen
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    Sracek, Ondra
    Bundschuh, Jochen
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Kar, Sandeep
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Management and Assessment.
    Chatterjee, Debashis
    Ahmed, Kazi Matin
    Jacks, Gunnar
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    Mukherjee, Arun B.
    Jean, Jiin-Shuh
    Arsenic-enriched groundwaters of India, Bangladesh and Taiwan-Comparison of hydrochemical characteristics and mobility constraints2011In: Journal of Environmental Science and Health. Part A: Toxic/Hazardous Substances and Environmental Engineering, ISSN 1093-4529, E-ISSN 1532-4117, Vol. 46, no 11, p. 1163-1176Article in journal (Refereed)
    Abstract [en]

    Arsenic (As) enrichment in groundwater has become a major global environmental disaster. Groundwater samples were collected from 64 sites located in the districts of 24-Parganas (S), and Nadia in West Bengal, India (Bhagirathi sub-basin), and 51 sites located in the districts of Comilla, Noakhali, Magura, Brahman baria, Laxmipur, Munshiganj, Faridpur and Jhenaida in Bangladesh (Padma-Meghna sub-basin). Groundwater samples were also collected from two As-affected areas (Chianan and Lanyang plains) of Taiwan (n = 26). The concentrations of major solutes in groundwater of the Padma-Meghna sub-basin are more variable than the Bhagirathi sub-basin, suggesting variations in the depositional and hydrological settings. Arsenic concentrations in groundwaters of the studied areas showed large variations, with mean As concentrations of 125 mu g/L (range: 0.20 to 1,301 mu g/L) in Bhagirathi sub-basin, 145 mu g/L (range: 0.20 to 891 mu g/L) in Padma-Meghna sub-basin, 209 mu g/L (range: 1.3 to 575 mu g/L) in Chianan plain, and 102 mu g/L (range: 2.5 to 348 mu g/L) in Lanyang plain groundwater. The concentrations of Fe, and Mn are also highly variable, and are mostly above the WHO-recommended guideline values and local (Indian and Bangladeshi) drinking water standard. Piper plot shows that groundwaters of both Bhagirathi and Padma-Meghna sub-basins are of Ca-HCO(3) type. The Chianan plain groundwaters are of Na-Cl type, suggesting seawater intrusion, whereas Lanyang plain groundwaters are mostly of Na-HCO(3) type. The study shows that reductive dissolution of Fe(III)-oxyhydroxides is the dominant geochemical process releasing As from sediment to groundwater in all studied areas.

  • 33. Mukherjee, A.
    et al.
    Fryar, A. E.
    Scanlon, B. R.
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Bhattacharya, A.
    Wide spread arsenic in deeper groundwater of western Bengal basin, West Bengal, India: Implications for sustainable alternate drinking water sources2012In: Understanding the Geological and Medical Interface of Arsenic, As 2012 - 4th International Congress: Arsenic in the Environment, Taylor & Francis Group, 2012, p. 522-525Conference paper (Refereed)
    Abstract [en]

    Availability of safe drinking water is a major concern in the delta plains of the major Himalayan-Tibetan rivers in southern and southeastern Asia. While indiscriminate use of rivers and other surface water bodies for disposal of sewage and industrial waste has rendered them non-potable, natural, non-point source, elevated Arsenic (As) concentrations in groundwater exceeding the World Health Organization's (WHO) guideline value for drinking water of 0.01 mg/L have put millions of people at risk. Hence, finding an alternate, suitable and sustainable drinking-water source has been a priority in these areas. Generally, higher concentrations of dissolved As are found in groundwater of shallower aquifers and several studies have advocated deeper aquifers as a possible safe substitute. Using a composite hydro-geological approach, we demonstrate that regional-scale deeper groundwater As contamination in the western Bengal basin is dependent on the aquifer-aquitard framework and complex redox processes with partial equilibrium under natural flow conditions. Widespread deep irrigation pumping may be drawing shallower, contaminated groundwater down to greater depths. These findings have severe implications on finding alternate drinking water sources, in West Bengal, and adjoining areas of Bangladesh, with plausible similar geological and hydrogeological framework.

  • 34.
    Mukherjee, A.
    et al.
    IIT, Dept Geol & Geophys, Kharagpur, W Bengal, India..
    Fryar, A. E.
    Univ Kentucky, Dept Earth & Environm Sci, Lexington, KY USA..
    Scanlon, B. R.
    Univ Texas Austin, Bur Econ Geol, Jackson Sch Geosci, Austin, TX USA..
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Bhattacharya, A.
    Govt West Bengal, Publ Hlth Engn Directorate, Kolkata, India..
    Wide spread arsenic in deeper groundwater of western Bengal basin, West Bengal, India: Implications for sustainable alternate drinking water sources2012In: UNDERSTANDING THE GEOLOGICAL AND MEDICAL INTERFACE OF ARSENIC, AS 2012 / [ed] Ng, JC Noller, BN Naidu, R Bundschuh, J Bhattacharya, P, CRC PRESS-TAYLOR & FRANCIS GROUP , 2012, p. 522-525Conference paper (Refereed)
    Abstract [en]

    Availability of safe drinking water is a major concern in the delta plains of the major Himalayan-Tibetan rivers in southern and southeastern Asia. While indiscriminate use of rivers and other surface water bodies for disposal of sewage and industrial waste has rendered them non-potable, natural, non-point source, elevated Arsenic (As) concentrations in groundwater exceeding the World Health Organization's (WHO) guideline value for drinking water of 0.01 mg/L have put millions of people at risk. Hence, finding an alternate, suitable and sustainable drinking-water source has been a priority in these areas. Generally, higher concentrations of dissolved As are found in groundwater of shallower aquifers and several studies have advocated deeper aquifers as a possible safe substitute. Using a composite hydrogeological approach, we demonstrate that regional-scale deeper groundwater As contamination in the western Bengal basin is dependent on the aquifer-aquitard framework and complex redox processes with partial equilibrium under natural flow conditions. Widespread deep irrigation pumping may be drawing shallower, contaminated groundwater down to greater depths. These findings have severe implications on finding alternate drinking water sources, in West Bengal, and adjoining areas of Bangladesh, with plausible similar geological and hydrogeological framework.

  • 35. Ngirane-Katashaya, G.
    et al.
    Kizito, Frank William
    Makerere University, Kampala, Uganda .
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630), Environmental Geochemistry and Ecotechnology.
    Decision Support Systems for Water Resources Management in Uganda: The Need2007In: Sustainable Development of Water Resources, Water Supply and Environmental Sanitation: Proceedings of the 32nd WEDC International Conference, 2007, p. 267-270Conference paper (Refereed)
    Abstract [en]

    Water is a major factor in the socio-economic fabric of Ugandan society and a major determinant of the development potential of the country. However, management of water resources is a complex problem that typically involves a variety of stakeholder interests and environmental uncertainties. The plurality of concerns establishes a pressing need for improved planning and management capabilities, and in this respect it has been noted that decision-making related to water resource management would benefit from engineering expertise combined with suitable use of informatics. In spite of rapidly advancing computer technology and the proliferation of software for decision support, relatively few Decision Support Systems have been developed, implemented, and evaluated in the field of water resources management in Uganda. Such tools need to be structured to fit in with existing policy frameworks in Uganda?s water sector, and should be tailored to the local conditions prevailing in the country.

  • 36.
    Ormachea Muñoz, Mauricio
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Wern, Hannes
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Johnsson, Fredrick
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Sracek, O.
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Quintanilla, J.
    Bundschuh, Jochen
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Geogenic arsenic and other trace elements in the shallow hydrogeologic system of Southern Poopó Basin, Bolivian Altiplano2013In: Journal of Hazardous Materials, ISSN 0304-3894, E-ISSN 1873-3336, Vol. 262, p. 924-940Article in journal (Refereed)
    Abstract [en]

    Environmental settings in the southern area of Lake Poopó in the Bolivian highlands, the Altiplano, have generated elevated amounts of arsenic (As) in the water. The area is characterised by a semiarid climate, slow hydrological flow and geologic formations of predominantly volcanic origin. The present study aimed at mapping the extent of the water contamination in the area and to investigate the geogenic sources and processes involved in the release of As to the groundwater.Ground- and surface-water samples were collected from 24 different sites, including drinking water wells and rivers, in the southern Poopó basin in two different field campaigns during the dry and rainy seasons. The results revealed variable levels of As in shallow drinking water wells and average concentration exceeding the WHO guidelines value. Arsenic concentrations range from below 5.2μg/L (the detection level) to 207μg/L and averages 72μg/L. Additionally, high boron (B) concentrations (average 1902μg/L), and high salinity are further serious concerns for deteriorating the groundwater quality and rendering it unsuitable for drinking. Groundwater is predominantly of the Na-Cl-HCO3 type or the Ca-Na-HCO3 type with neutral or slightly alkaline pH and oxidising character. While farmers are seriously concerned about the water scarcity, and on a few occasions about salinity, there are no concerns about As and B present at levels exceeding the WHO guidelines, and causing negative long term effects on human health.Sediment samples from two soil profiles and a river bed along with fourteen rock samples were also collected and analysed. Sequential extractions of the sediments together with the calculation of the mineral saturation indices indicate that iron oxides and hydroxides are the important secondary minerals phases which are important adsorbents for As. High pH values, and the competition of As with HCO3 and dissolved silica for the adsorption sites probably seems to be an important process for the mobilisation of As in the shallow groundwaters of the region. Continuous monitoring and expansion of monitoring systems are necessary prerequisites for better understanding of the pattern of As mobilisation in the Southern Poopó Basin.

  • 37. Quintanilla, J.
    et al.
    Ramos Ramos, O.E.
    Ormachea, Muñoz Mauricio
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    Garcia, M.E.
    Medina, H.
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Management and Assessment.
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    Arsenic contamination, speciation and environmental consequences in the Bolivian plateau2009In: Natural Arsenic in Groundwater of Latin America: Occurrence, health impact and remediation, The Netherlands: CRC Press/Balkema , 2009, p. 91-100Chapter in book (Refereed)
  • 38. Ramanathan, A. L.
    et al.
    Tripathi, P.
    Ranjan, R.
    Kumar, M.
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630).
    Elfverson, Katarina
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630).
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630).
    Jacks, Gunnar
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630).
    Sracek, O.
    Bundschuh, Jochen
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630). Karlsruhe University of Applied Sciences, Karlsruhe, Germany .
    Tsujimura, M.
    Hydrogeochemistry of the alluvial aquifers of the central Gangetic Plain in India: Constraints on source and mobility of arsenic2010In: Arsenic in Geosphere and Human Diseases, As 2010 - 3rd International Congress: Arsenic in the Environment, 2010, p. 23-25Conference paper (Refereed)
  • 39. Ramanathan, A.L.
    et al.
    Tripathi, P.
    Kumar, M.
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Management and Assessment.
    Bundschuh, J.
    Arsenic distribution in the groundwater in Central Gangetic Plains of Uttar Pradesh, India2009In: Arsenic distribution in the groundwater in Central Gangetic Plains of Uttar Pradesh, India: Occurrence, health impact and remediation, The Netherlands: CRC Press/Balkema , 2009, p. 215-224Chapter in book (Refereed)
  • 40. Ramos, O.
    et al.
    Ormachea, M.
    Niura, M.
    García, M. E.
    Quintanilla, J.
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630).
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630).
    Jacks, Gunnar
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630).
    Sracek, O.
    Arsenic and other trace elements in groundwater and surface water of the Poopó Basin and drinking water quality in Bolivian Altiplano2010In: Arsenic in Geosphere and Human Diseases, As 2010 - 3rd International Congress: Arsenic in the Environment, 2010, p. 517-519Conference paper (Refereed)
  • 41.
    Ramos Ramos, Oswaldo Eduardo
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Cáceres, L.F.
    Ormachea Muñoz, Mauricio Rodolfo
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Quino, I.
    Quintanilla, J.
    Sracek, O.
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Bundschuh, Jochen
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    García, M. E.
    Sources and behavior of arsenic and trace elements in groundwater and surface water in the Poopó Lake Basin, Bolivian Altiplano2012In: Environmental Earth Sciences, ISSN 1866-6280, Vol. 66, no 3, p. 793-807Article in journal (Refereed)
    Abstract [en]

    Water management in semiarid and arid catchments such as the Poopó Lake Basin requires improved understanding of the complex behavior of the various contaminants, which affect the drinking water quality and considered as crucial for sustainable development of the region. Mechanisms of arsenic (As) release in the surface and groundwater were studied. Hydrochemical data for surface water (4 samples) and groundwater (28 samples) were collected in a small watershed in the Poopó catchment at the highland of the Bolivian Andes (Altiplano). All of them show high electrical conductivity values and moderately oxidizing conditions. The surface water contains high concentration of sulfate and the trace elements As, Zn and Pb in the zone affected by acid mine drainage. There is a large variability of the concentration of As and of the trace elements in the groundwater in the five different regions within the Poopó catchment. The metal concentrations sensitive to changes of redox state and results of speciation modeling suggest that As (V) is a predominant aqueous species, which conforms to the prevailing oxidizing conditions in the shallow groundwater environment. Two generalized trends for As distribution were identified in groundwater: (a) high concentrations are found in the arid zone (100-250 Όg/L) in the southern (region III) and in the northwestern (region V) regions, and (b) low concentrations (< 50 Όg/L) are found in the remaining part of the basin (region I, II and IV). However, the spatial distribution within these regions needs to be investigated further. A conclusion from the present study is that there are multiple sources of As as well as other trace elements (such as Cd, Mn and Zn) in the Poopó Lake Basin. Among the sources and the processes which led to the mobility of As and other trace metals in the region are: (a) weathering of sulfide minerals, (b) oxidation of pyrite and/or arsenopyrite in mineralized areas and (c) desorption from hydrous ferric oxide (HFO) surfaces. In non-mining areas, volcanic ash is suggested to be a significant source of As.

  • 42. Robinson, Clare
    et al.
    von Brömssen, Mattias
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    Häller, Sara
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    Bivén, Annelle
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    Hossain, Mohammed
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    Jacks, Gunnar
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    Ahmed, Kazi Matin
    Hasan, M. Aziz
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Management and Assessment.
    Dynamics of arsenic adsorption in the targeted arsenic-safe aquifers in Mat lab, south-eastern Bangladesh: Insight from experimental studies2011In: Journal of Applied Geochemistry, ISSN 0883-2927, Vol. 26, no 4, p. 624-635Article in journal (Refereed)
  • 43.
    Shammas, Mahaad
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Predictive simulation of flow and solute transport for managing the Salalah coastal aquifer, Oman2009In: Water resources management, ISSN 0920-4741, E-ISSN 1573-1650, Vol. 23, no 14, p. 2941-2963Article in journal (Refereed)
    Abstract [en]

    A three-dimensional numerical model for flow and solute transport was used for the management of the Salalah aquifer. The model calibration procedures consisted of calibrating the aquifer system hydraulic parameters by history matching under steady and transient conditions. The history of input and output of the aquifer were reconstructed in a transient calibration from 1993 to 2005. Predictive simulation of the aquifer was carried out under transient conditions to predict the future demand of groundwater supply for the next 15 years. A baseline scenario was worked out to obtain the piezometric surface and salinity distribution for the "business as usual" conditions of the aquifer. The "business as usual" scenario was predicted and simulated for the period 2006 until 2020. The effectiveness of seven management options was proposed and assessed for comparison with the "business as usual" conditions. The established simulation model was used to predict the distribution of the piezometric surface, salinity distribution, and mass balance under the proposed scenarios for the prediction period 2006-2020. The scenarios were: (1) relocate Garziz and MAF farms far from the freshwater zone, (2) suspend the abstraction of grass production for 4 months a year, (3) changes in agricultural and irrigation system patterns, (4) establish a desalination plant, (5) combined scenario (1 + 4), (6) combined scenario (1 + 3), and (7) combining all scenarios (1 + 2 + 3 + 4). The result of the simulation shows that the best effective option in terms of aquifer groundwater levels is the fifth proposed scenario and the sixth proposed scenario is the best effective option in terms of aquifer groundwater salinity situation during the next 15 years. This project suggested the application of scenario 6 as it is environmentally sound in terms of sustainable management. A prediction has been made which shows that further actions have to be taken within the next two decades to ensure continuity of the municipal water supply. The management scenarios are examined in the case of the Salalah coastal aquifer using groundwater simulation, which can also be applied to other regions with similar conditions. The established model is considered a reasonable representation of the physical conditions of the Salalah plain aquifer, and can be used as a tool by the water and environmental authorities in the management of the groundwater in the region.

  • 44.
    Sokrut, Nikolay
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Motovilov, Juri
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Skotte, G.
    Simulation of nitrate transport in the Vemmenhög catchment using the distributed hydrological model ECOMAG2005In: Nordic Hydrology, ISSN 0029-1277, E-ISSN 1996-9694Article in journal (Other academic)
  • 45.
    Sokrut, Nikolay
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Evaluation of uncertainties in simulation of hydraulic head fields by means of Bayesian updating techniques2005In: Journal of Geophysical Research, ISSN 0148-0227, E-ISSN 2156-2202Article in journal (Other academic)
  • 46.
    Sokrut, Nikolay
    et al.
    KTH, Superseded Departments, Land and Water Resources Engineering.
    Thunvik, Roger
    KTH, Superseded Departments, Land and Water Resources Engineering.
    Motovilov, Juri
    ECOFLOW: a Distributed Integrated Hydrological Model as a Tool for Catchment Management2003Conference paper (Refereed)
  • 47.
    Sokrut, Nikolay
    et al.
    KTH, Superseded Departments, Land and Water Resources Engineering.
    Thunvik, Roger
    KTH, Superseded Departments, Land and Water Resources Engineering.
    Motovilov, Juri
    Evaluation of uncertainties in simulation of hydraulic head fields by means of Bayesian updating techniques2003Conference paper (Refereed)
  • 48.
    Sokrut, Nikolay
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Motovilov, Juri
    Örsundaån case: an example of multiple-scale hydrological modelling2005In: Journal of Hydrology, ISSN 0022-1694, E-ISSN 1879-2707Article in journal (Other academic)
  • 49.
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Management and Assessment.
    Book review & dynamics of Fluids and Transport in Fractured Rock2008In: Geofluids, ISSN 1468-8115, E-ISSN 1468-8123, Vol. 8, no 2, p. 140-142Article in journal (Refereed)
  • 50.
    von Brömssen, Martin
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Markussen, Lars
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Ahmed, Kazi Matin
    Hossain, Mohammed
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Jacks, Gunnar
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Sracek, Ondra
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Hasan, Md Aziz
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Islam, M. Mainul
    Rahman, M. Mokhlesur
    Hydrogeological investigation for assessment of the sustainability of low-arsenic aquifers as a safe drinking water source in regions with high-arsenic groundwater in Matlab, southeastern Bangladesh2014In: Journal of Hydrology, ISSN 0022-1694, E-ISSN 1879-2707, Vol. 518, no C, p. 373-392Article in journal (Refereed)
    Abstract [en]

    Exploitation of groundwater from shallow, high prolific Holocene sedimentary aquifers has been a main element for achieving safe drinking water and food security in Bangladesh. However, the presence of elevated levels of geogenic arsenic (As) in these aquifers has undermined this success. Except for targeting safe aquifers through installations of tubewells to greater depth, no mitigation option has been successfully implemented on a larger scale. The objective of this study has been to characterise the hydrostratigraphy, groundwater flow patterns, the hydraulic properties to assess the sustainability of the low-arsenic aquifers at Matlab, in south-eastern Bangladesh, one of the worst arsenic-affected areas of Bangladesh. Combining groundwater modelling with monitoring hydraulic heads in multi-level piezometer tests, 14C-dating of groundwater, conventional hydraulic testing and assessment of groundwater abstraction rate proved to be a useful strategy. A model comprising of three aquifers covering the top 250 m of the model domain showed to best fit the evaluation criteria for calibration. Matlab is a recharge area, even though it is adjacent to the great Meghna River. Irrigation wells are placed in clusters and account for most of the groundwater abstraction. Even though the hydraulic heads are affected locally by seasonal pumping, the aquifer system is fully recharged during and after the monsoon period. Groundwater simulations demonstrated the presence of deep regional and horizontal flow systems with recharge areas in the eastern, hilly part of Bangladesh and shallow small local flow systems driven by local topography. Based on modelling and 14C groundwater data, it can be concluded that the natural local flow systems reach a depth of 30 m b.g.l. in the study area. A downwardvertical gradient of roughly 0.01 down to 200 m b.g.l. was observed and reproduced bycalibrated models. The vertical gradient is mainly the result of the aquifer system and-properties rather than abstraction rate, which is too limited at depth to make an imprint. Although irrigation wells substantially change local flow pattern, targeting low-As aquifers seems to be a suitable mitigation option for providing people with safe drinkingwater. However, installing new irrigation- or high capacity production wells at the same depth is strongly discouraged as these substantially change the groundwater flow pattern. The results from the present study and other similar studies can further contribute to develop a rational management and mitigation policy for the future use of the groundwater resources for drinking water supplies.

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