Display options:
Normal
Show Abstracts
Compact
Select/unselect all
Displaying article 1-11
p. 283-294
Received: 19 January 2012; in revised form: 1 March 2012 / Accepted: 1 March 2012 / Published: 23 March 2012
Show/Hide Abstract
| Download PDF Full-text (217 KB) | Download XML Full-text Abstract: In this work, the ability of a commercial spiral-wound nanofiltration membrane to remove hardness and ions from diluted seawater was studied. Experiments were carried out in the pressure range of 4–10 bar. Analyses of the samples, and permeates at different pressures, were performed and the effects of the trans-membrane pressure on the permeate flux were investigated. The results show that this nanofiltration membrane is capable of retaining 96–98% of the total hardness, 79–89% of the electrical conductivity and 79–89% of the total dissolved solid (TDS). Our results are in good agreement with those reported by the manufacturing company.
p. 295-320
Received: 7 February 2012; in revised form: 27 February 2012 / Accepted: 8 March 2012 / Published: 23 March 2012
Show/Hide Abstract
| Download PDF Full-text (2476 KB) | Download XML Full-text Abstract: The Dutch Delta Program is currently developing new government policies for flood protection and fresh water supply. Decision support instruments have to address the program’s technical and political complexity. The water system functions are highly interwoven and would benefit from an integrated approach on a national level, with decisions supported by a scientific Systems Analysis. Politically, there is a tendency towards broad participation and decentralization, and decision-making is typically supported by Conflict Resolution methods. To connect these two sides of the Delta Program’s task, an outline is presented of an internet community-based interactive instrument, preliminarily named SimDelta. On-line interactive maps and elements of serious gaming intuitively provide local Delta Program participants insight into the interaction between scenarios, problems, and solutions. SimDelta uses the internet to more frequently and efficiently present conceptual designs by architects and engineers to the Delta Program stakeholders, record their preferences, and “crowdsource” corrections, improvements and new ideas.
p. 321-344
Received: 2 February 2012; in revised form: 13 March 2012 / Accepted: 21 March 2012 / Published: 27 March 2012
Show/Hide Abstract
| Download PDF Full-text (1759 KB) | Download XML Full-text Abstract: The investigation of electric arc furnace (EAF) steel slag as a viable add-on technology to existing stormwater systems for the removal of dissolved phosphorus (P) was extended to explore the effects of varying environmental and treatment system conditions. Parameters such as stormwater composition, P concentration, metal concentration, pH, temperature, slag mass and slag particle size were varied. Observations relating to the method of P removal via EAF slag were also carefully considered to explain removal mechanisms involved. Results demonstrated that, although physisorption contributed to P reduction, it was not the key P removal mechanism. Instead, precipitation was observed to be a key removal pathway as evidenced by the correlation between the loss of iron (Fe) from slag and the amount of P removed from solution. The reduced removal of P by slag in a copper-dominant stormwater solution was attributed to the formation of a stable complex formed by the interaction of copper with the slag via the ion-exchange surface model. The stability of this complex inhibits the loss of Fe from the EAF slag and, consequently, P removal by means of precipitation. In terms of the effect of changing environmental and treatment system conditions on the P removal process, stormwater composition, P concentration, metal concentration, pH, temperature, slag mass and slag particle size were found to significantly influence the effectiveness of EAF slag in removing P from a given stormwater system. It was also established that a number of combinations of these factors influence P uptake differently.
p. 345-366
Received: 15 February 2012; in revised form: 12 March 2012 / Accepted: 29 March 2012 / Published: 10 April 2012
Show/Hide Abstract
| Download PDF Full-text (525 KB) | Download XML Full-text | Abstract: Water is the primary medium through which climate change influences the Earth’s ecosystems and therefore people’s livelihoods and wellbeing. Besides climatic change, current demographic trends, economic development and related land use changes have direct impact on increasing demand for freshwater resources. Taken together, the net effect of these supply and demand changes is affecting the vulnerability of water resources. The concept of ‘vulnerability’ is not straightforward as there is no universally accepted approach for assessing vulnerability. In this study, we review the evolution of approaches to vulnerability assessment related to water resources. From the current practices, we identify research gaps, and approaches to overcome these gaps a generalized assessment framework is developed. A feasibility study is then presented in the context of the Lower Brahmaputra River Basin (LBRB). The results of the feasibility study identify the current main constraints (e.g., lack of institutional coordination) and opportunities (e.g., adaptation) of LBRB. The results of this study can be helpful for innovative research and management initiatives and the described framework can be widely used as a guideline for the vulnerability assessment of water resources systems, particularly in developing countries.
p. 367-388
Received: 22 February 2012; in revised form: 16 March 2012 / Accepted: 26 March 2012 / Published: 11 April 2012
Show/Hide Abstract
| Download PDF Full-text (842 KB) | Download XML Full-text Abstract: Recent literature outlines significant impacts from climate change on many areas of the world, with much focus on causes and impacts. However the long-term trends demand adaptation strategies. While a variety of solutions have been suggested, some politically viable, others not, perhaps the most significant barrier to a cohesive approach to climate adaptation is the failure from the public and policy-makers to realize that different areas will be affected differently and that “one-size-fits-all” policy solutions will not be successful. In addition, as one area may identify and respond to challenges in their location, others should be supportive of those efforts, realizing that while such actions may be neither desirable nor appropriate for them, they may need support for solutions in the future in their areas. This project was designed as a framework to identify solutions and demonstrate differences between small regions and locales based on field conditions. The State of Florida was used as a case example to outline these differences because Florida is faced with significant challenges in the coming years related to water resources, the use of funds and political capital, and the potential for economic disruption. The intent is that the results of this project will lead to a series of recommendations and action steps for policy makers to conserve the state’s assets. A similar approach can be used in other states and countries to assess the likely policy and infrastructure needs for different locales.
p. 389-429
Received: 27 February 2012; in revised form: 26 March 2012 / Accepted: 26 March 2012 / Published: 11 April 2012
Show/Hide Abstract
| Download PDF Full-text (661 KB) | Download XML Full-text Abstract: Controversy regarding the amount of water consumed or saved as a result of human activity is currently paramount in water-scarce areas. In recent decades, golf—a land and water consuming activity—has been implanted in several areas of the Mediterranean basin, where the scarcity of water resources is well-known. As a result, the use of conventional water resources for golf course irrigation is increasingly contested and its replacement by reclaimed water has become essential. This paper examines the wide range of issues involved in its use on golf courses, including hazards—due to the presence of microorganisms and pollutants—and the corresponding risks that can appear. The resulting biological, chemical and physical water quality concerns are analyzed. Legal aspects related to the use of reclaimed water are also discussed and good reuse practices are suggested, including a detailed examination of risk assessment procedures and tools through observation or chemical, physical and microbiological analysis. The HACCP system—which focuses on quality determination in water samples from relevant control points—is described in detail, as it is generally accepted as one of the most scientific ways to detect health problems on a golf course. The paper concludes that, given the increasing availability of treated and reclaimed water and the water needs of golf courses, the future development of the sport in areas without surplus water resources—such as the Mediterranean basin—will predictably depend upon the use of reclaimed water. In recent years, risk assessment or analysis has emerged as an essential tool to guarantee the application of reclaimed water at an acceptable risk level. There certainly have been considerable advances and improvements in the tools that guarantee the safe use of reclaimed water, although current methods available require simplification for their practical application. Nevertheless, protocols applied at present seem to be adequate in order to address the key issue of enhancing the development of reclaimed water use on golf courses.
p. 430-459
Received: 25 February 2012; in revised form: 16 April 2012 / Accepted: 18 April 2012 / Published: 26 April 2012
Show/Hide Abstract
| Download PDF Full-text (1721 KB) | Download XML Full-text Abstract: This paper demonstrates a methodology for integrating existing models for the rapid simulation of coastal flood events across a large and varied case study area on the UK south coast. Following validation against observations from real coastal floods, synthetic events driven by realistic waves and water levels and the full range of failure mechanisms were modelled for a range of loadings to generate peak flood water depths and an overview of impacts across this spectrum of possible floods. Overtopping is relatively important compared to breaching as coastal floodplains are small. This modelling system supports multiple potential applications, such as planning flood warnings, coastal defence upgrade, and land use, including under sea-level rise. The concepts drawn from this study are transferable to similar coastal regions.
p. 460-473
Received: 27 February 2012; in revised form: 27 March 2012 / Accepted: 13 April 2012 / Published: 27 April 2012
Show/Hide Abstract
| Download PDF Full-text (1072 KB) | Download XML Full-text | Abstract: Microalgae can be used for the treatment of municipal wastewater. The application of microalgal biofilms in wastewater treatment systems seems attractive, being able to remove nitrogen, phosphorus and COD from wastewater at a short hydraulic retention time. This study therefore investigates the area requirement, achieved effluent concentrations and biomass production of a hypothetical large-scale microalgal biofilm system treating municipal wastewater. Three scenarios were defined: using microalgal biofilms: (1) as a post-treatment; (2) as a second stage of wastewater treatment, after a first stage in which COD is removed by activated sludge; and (3) in a symbiotic microalgal/heterotrophic system. The analysis showed that in the Netherlands, the area requirements for these three scenarios range from 0.32 to 2.1 m2 per person equivalent. Moreover, it was found that it was not possible to simultaneously remove all nitrogen and phosphorus from the wastewater, because of the nitrogen:phosphorus ratio in the wastewater. Phosphorus was limiting in the post-treatment scenario, while nitrogen was limiting in the two other scenarios. Furthermore, a substantial amount of microalgal biomass was produced, ranging from 13 to 59 g per person equivalent per day. These findings show that microalgal biofilm systems hold large potential as seasonal wastewater treatment systems and that it is worthwhile to investigate these systems further.
p. 474-493
Received: 9 April 2012; in revised form: 2 May 2012 / Accepted: 4 May 2012 / Published: 11 May 2012
Show/Hide Abstract
| Download PDF Full-text (566 KB) | Download XML Full-text Abstract: The Rhine River Delta is crucial to the Dutch economy. The Maeslant barrier was built in 1997 to protect the Rhine estuary, with the city and port of Rotterdam, from storm surges. This research takes a simple approach to quantify the influence of the Maeslant storm surge barrier on design water levels behind the barrier. The dikes in the area are supposed to be able to withstand these levels. Equal Level Curves approach is used to calculate the Rotterdam water levels by using Rhine discharges and sea water levels as input. Their joint probability function generates the occurrence frequency of a certain combination that will lead to a certain high water level in Rotterdam. The results show that the flood frequency in Rotterdam is reduced effectively with the controlled barrier in current and in future scenarios influenced by climate change. In addition, an investigation of the sensitivity of the operational parameters suggests that there is a negligible influence on the high water level frequency when the decision closing water level for the barrier is set higher due to the benefits of navigation (but not exceeding the design safety level 4 m MSL).
p. 494-495
Received: 16 May 2012 / Published: 18 May 2012
Show/Hide Abstract
| Download PDF Full-text (122 KB) | Download XML Full-text Abstract: The following paragraphs are reproduced from the website of the publisher [1].Disinfection By-Products and Human Health is based on contributions from speakers who participated in May 2011 workshops on Disinfection By-Products (DBPs) and Human Health at Ozwater 11 in Adelaide, Australia or at an AWA sponsored workshop at the Curtin Water Quality Research Centre, Perth, Australia.The contributions are prepared to facilitate communication with practitioners, rather than researchers, making use of overview illustrations rather than dense text or data tables. Each chapter concludes with up to 5 key findings that are take-home messages for practitioners. [...]
p. 496-509
Received: 24 February 2012; in revised form: 15 May 2012 / Accepted: 18 May 2012 / Published: 29 May 2012
Show/Hide Abstract
| Download PDF Full-text (416 KB) | Download XML Full-text Abstract: Several studies have shown concern over nitrate and nitrite contamination of prepared infant formula used by infants less than six months old, as it may lead to methemoglobinemia and death. One possible source of contamination is through the use of improperly treated drinking water. Contamination of water could result from fertilizers and manure runoff, not fully treated and released human and industrial waste, or from disinfection processes. In the United Arab Emirates (UAE), bottled water is the major source of drinking water and may be used for the preparation of infant formula. Therefore, in this study, several bottled water brands that are sold on the UAE market, and could be used for preparation of infant formula, were tested for nitrate and nitrite and other anions to show their compatibility with the permissible levels of the United States Environmental Protection Agency (U.S. EPA), United States Food and Drug Administration/Code of Federal Regulations (U.S. FDA/CFR), and other international organizations. All the bottled water samples demonstrated nitrate, nitrite, and other anions levels below the permissible levels accepted by U.S. EPA, U.S. FDA/CFR, and other international organizations, except for one sample that showed nitrite levels exceeding the European Commission and Drinking Water Directive (EC/DWD) permissible levels. Such study sheds light on the quality of bottled water sold not only in the UAE and the region, but also in other countries, such as France, since some of them are imported. In addition, the results shed light on the effectiveness of the treatment processes and possible sources of infant formula contamination that can affect the health of infants.
Select/unselect all
Displaying article 1-11
Export citation of selected articles as:
Plain Text
BibTeX
BibTeX (without abstracts)
Endnote
Endnote (without abstracts)
Tab-delimited
PubMed XML
DOAJ XML
AGRIS XML