Highway filter drain waste arisings: a challenge for urban source control management?

Essential maintenance activities on highway BMP drainage controls involve refurbishment of filter (French) drains which can generate substantial amounts of "controlled waste". An innovative procedure for their re-instatement is described which offers a more sustainable option for filter drain/trench management. The quality classification of these waste arisings is problematical and it is difficult to reliably identify the risks posed by such materials and the most effective forms of management and disposal options.     

Hydrosolidarity and beyond: can ethics and equity find a place in today's water resource management?

The notion of hydrosolidarity has permeated international discourses on water management, but it has received little comprehensive review. This paper traces the intellectual origins of hydrosolidarity and it explores how the concept has been applied by water scholars, organizations and in global water venues, like World Water Forums. Evolving conceptions and meanings of hydrosolidarity are presented and its kinship to related, sometimes oppositional terms, untangled. In particular, it explores how hydrosolidarity has evolved to serve as a socio-ethical annex to integrated water resources management. The paper concludes by examining some critiques and addressing the potential of hydrosolidarity in water management.     

On-site stormwater detention for Australian development projects: Does it meet frequent flow management objectives?

On-site stormwater detention(OSD) is a conventional component of urban drainage systems, designed with the intention of mitigating the increase to peak discharge of stormwater runoff that inevitably results from urbanization. In Australia, singular temporal patterns for design storms have governed the inputs of hydrograph generation and in turn the design process of OSD for the last three decades. This paper raises the concern that many existing OSD systems designed using the singular temporal pattern for design storms may not be achieving their stated objectives when they are assessed against a variety of alternative temporal patterns. The performance of twenty real OSD systems was investigated using two methods:(1) ensembles of design temporal patterns prescribed in the latest version of Australian Rainfall and Runoff, and(2) real recorded rainfall data taken from pluviograph stations modeled with continuous simulation. It is shown conclusively that the use of singular temporal patterns is ineffective in providing assurance that an OSD will mitigate the increase to peak discharge for all possible storm events. Ensemble analysis is shown to provide improved results. However, it also falls short of providing any guarantee in the face of naturally occurring rainfall.     

Integrated water resources management: lost on the road from ambition to realisation?

The recognition that water plays a central role in industrial, agricultural, economic, social and cultural development has, over the past half century, led to the development of strategic management approaches based on the concept of integrated water resources management (IWRM). This paper assesses the extent to which IWRM theory has been converted into practice and identifies existing "research gaps". We set out our arguments as a critique of IWRM; describing its basic tenets, exploring its value as a conceptual tool, considering its scientific pedigree, questioning its novelty as a resource management paradigm, and suggesting ways of translating the theory into more widespread practice. Finally, we argue that whilst models in their broadest sense can make a significant contribution to IWRM research and practice, a revised assessment of the source of their value is required.     

Policy options for promoting urban–rural cooperation in water management: a review

As most cities share their water basins with rural areas, an efficient and environmentally sensible urban water management system needs to consider the interplay between urban and rural water uses. This article analyses the three main challenges at this interface: increased competition for water resources (scarcity); flood management (abundance); and freshwater quality conservation (pollution). The merit of potential policy options is discussed from an economics perspective, taking examples from successful experiences in cities around the world. The benefits and challenges arising from enhanced coordination and integration between urban and rural water management are highlighted.     

Sleeping with the enemy? Capturing internal risks in the logical framework of a water management project

Logframes are fundamental to contemporary development. However, there are ongoing debates about their efficacy. This paper pinpoints the limitations of the logframe approach in a water project in Central Asia. Issues surrounding logframes are identified. These include addressing internal risks; the use of baseline studies for the accuracy of assumptions; the ability to adapt under an inflexible budget; and linking the logframe and contract. Findings show that rigid planning may constrain effective project implementation. Greater flexibility through embedded learning and adaptation, adjustable budgets and meaningful mainstreaming of risks may equip projects to cope with uncertainties to achieve sustainability.     

Particle counting as a tool to predict filterability in membrane bioreactors activated sludge?

Activated sludge quality is one of the major factors influencing flux decline in membrane bioreactors (MBRS). Sludge filterability is a recognized parameter to characterize the physical properties of activated sludge. Decrease in filterability is linked to a higher number of submicron particles. In our present research we studied whether particle counting techniques can be used to indicate deflocculation of the sludge suspended fraction to submicron particles, causing the aforementioned filterability decrease. A total number of 105 activated sludge samples were collected in four full scale municipal MBRS. Samples were tested for filterability and particle counting in the range 2-100 microm. In 88% of the membrane tank samples the filterability varied between good and poor, characterized by the deltaR20, being 0 < deltaR20 < 1. Filterability varied following the season of the year, stability of the MBR operation and recirculation ratio. The membrane tank filterability can be improved by applying low recirculation ratio between MBR tanks. The applied particle counting methodology generated reproducible and reliable results in the range 10-100 microm. Results show that differences in filterability cannot be explained by variations in particle size distribution in the range 10-100 microm. However, measurable deflocculation might be masked by the large numbers of particles present. Therefore, we cannot exclude the suspended particles as a possible source of submicron particles that are subsequently responsible for MBR sludge filterability deterioration.     

Irrigation infrastructure development in the Limarí Basin in Central Chile: implications for adaptation to climate variability and climate change

One option to deal with climate variability in agriculture is to build irrigation infrastructure, although this may lead to the overdevelopment of water resources, leading to ‘basin closure’. The Limarí Basin, in central north Chile, has relied on irrigation infrastructure over the last 30 years to increase water supply reliability and extend irrigated acreage, especially for permanent crops. This situation has reduced adaptation opportunities in the basin, which is currently experiencing a severe drought that, according to climate change projections, is expected to persist in the future, with important consequences for the sustainability of agriculture production.     

Water productivity and water footprint: misguided concepts or useful tools in water management and policy?

Water productivity (WP) and water footprint (WFP) are popular concepts in research and discourses on water management. Yet there are concerns about their theoretical validity and practical value. This paper shows that the water production function, the concept with a sound theoretical foundation, is the basis for WP. Total WFP is the reciprocal of WP. The practical value of WP and WFP depends on the context of water use and stress. Maximizing WP, not a panacea to all water problems, mainly suits arid rainfed areas. In other regions, economic and marginal WP for increasing overall production should take precedence in water management and policy decisions.     

Difficulties of fishing at Lake Naivasha,Kenya: is community participation in management the solution?

Unlike other lakes in tropical regions, Lake Naivasha exhibits low fish species diversity. The fishery is based on introduced fish species that are not native to the lake. The lake ecosystem is very fragile, as reflected in its fluctuating fish catches. The fishery almost completely collapsed in 2001, due partly to mismanagement and ignorance about needed conservation measures. The Kenyan government, like many governments around the world, recognized the need to involve fishers and other stakeholders, in order to ensure better management of the lake fisheries resources. Also referred to as collaborative management (co-management), this management approach provides the opportunity to share responsibility for managing the fishery resources between the government and the community. A total ban on fishing was imposed in February 2001, lasting for 1 year, to allow lake fish stocks to recover. This study analyses the co-management process for Lake Naivasha, and discusses the role played by the community during the fishing ban, as well as the successes and challenges encountered, and the tribulations and perceptions of the fishers regarding the new management strategy. It also comprises the first documentation of community participation in fisheries management begun for Lake Naivasha in the year 2001.     

The Afghan water law: “a legal solution foreign to reality”? 1

In this article the suggested permit and licence systems included in the draft Afghan Water Law of 2008 (superseding those laws of 1981 and 1991) are examined by comparing them with main canal data from two pilot studies within the Kunduz Basin. The comparison highlights the difficulty of making these proposed legal frameworks operative. Overall, it appears that the sections within the law on permits and licences are not implementable within or even useful for the traditional irrigation systems, but mainly play into the hands of the national hydrocracy and please international donors.     

Fouling cake layer in a submerged anaerobic membrane bioreactor treating saline wastewaters: curse or a blessing?

The treatment of inhibitory (saline) wastewaters is known to produce considerable amounts of soluble microbial products (SMPs), and this has been implicated in membrane fouling; the fate of these SMPs was of considerable interest in this work. This study also investigated the contribution of SMPs to membrane fouling of the; (a) cake layer/biofilm layer, (b) the compounds below the biofilm/cake layer and strongly attached to the surface of the membrane, (c) the compounds in the inner pores of the membrane, and (d) the membrane. It was found that the cake/biofilm layer was the main reason for fouling of the membrane. Interestingly, the bacteria attached to the cake/biofilm layer showed higher biodegradation rates compared with the bacteria in suspension. Moreover, the bacteria attached to the cake layer showed higher amounts of attached extracellular polysaccharides (EPS) compared with the bacteria in suspension, possibly due to accumulation of the released EPS from suspended biomass in the cake/biofilm layer. Molecular weight (MW) analysis of the effluent and reactor bulk showed that the cake layer can retain a large fraction of the SMPs in the reactor and prevent them from being released into the effluent. Hence, while cake layers lead to lower fluxes in submerged anaerobic membrane bioreactors (SAMBRS), and hence higher costs, they can improve the quality of the reactor effluent.     

Data-sharing bottlenecks in transboundary integrated water resources management: a case study of the Mekong River Commission’s procedures for data sharing in the Thai context

Integrated water resources management (IWRM) relies on co-ordination, co-operation and sharing of collected data amongst relevant organizations. This article presents the results of systematic research into non-technical barriers that influence IWRM-related data sharing in transboundary contexts, with a focus on the Mekong River Commission’s procedures for data sharing in Thailand. The current extent of data sharing is quite limited. The main bottlenecks hindering relevant Thai organizations’ sharing data across national boundaries appear to be a perception of limited gains, and concerns for national security. The article concludes that data sharing for IWRM implementation cannot be radically improved without significant changes in the mindsets of the relevant organizations, and suggests how to achieve this.     

Coping with water supply interruptions: can citizen voice in transdisciplinary research make a difference?

Despite explicit legal and policy commitments, many South African residents do not have reliable access to potable water. Resident dissatisfaction with municipal water service delivery is evidenced by frequent civil protests. We consider how gathering and understanding the lived experiences of citizens could influence official responses to water interruptions. We take a transdisciplinary, problem-focussed, research approach to the experience of, and responses to, water interruptions, reflecting on the limitations of research to effect change in the lived experience. As transdisciplinary research praxis increasingly seeks expression in social outcomes, it is vital to confront both opportunities and limitations.     

Let’s bring in the floods: de-poldering in the Netherlands as a strategy for long-term delta survival?

Controlled flooding, while heavily contested, is being experimented with in the Dutch delta as a new and ecologically oriented strategy to deal with floods, in contrast to the conventional flood prevention paradigm. The Noordwaard project (2012–15) represents an exemplary case. At the expense of agricultural practices, land is set aside occasionally to accommodate river floods, while restored flood and tidal dynamics aim to benefit nature development. It is argued that although controlled flooding aims to restore historical land and water dynamics in the area, the role of sedimentation processes has remained largely unaddressed in relation to shaping long-term delta futures.     

Invertebrate drift patterns in a regulated river: dams,periphyton biomass or longitudinal patterns?

Macroinvertebrate drift was sampled at 15 sites along the Tongariro River, New Zealand above and below two hydroelectric dams. Sixty‐seven invertebrate taxa were collected in the drift. Trichoptera (31) were the most diverse, followed by Diptera (13), Ephemeroptera (8) and Plecoptera (8). However, chironomidae were the numerically dominant taxa in the drift throughout the river and represented over 80% of all animals collected. Of these, Orthocladiinae and Diamesinae were the most abundant. Taxonomic richness declined with distance downstream and peaked at sites with intermediate levels of periphyton biomass. The per cent of Ephemeroptera, Plecoptera and Trichoptera (EPT) was 3–4 times higher in the unregulated section of the river and declined exponentially with both distance downstream and increase in periphyton biomass, but densities were similar along the river. Of the measured environmental variables periphyton biomass was most closely linked with drift community structure. Periphyton biomass was six times higher in the lower section of the river than the upper unregulated section. The autocorrelation between periphyton biomass and distance downstream complicates the interpretation of results. However, because of the distinct differences between above and below dam sections of river in periphyton biomass and the strong link between it and invertebrate drift we suggest that the alteration of flow patterns by the hydroelectric dams and the associated shift in periphyton biomass is the most likely explanation for invertebrate drift patterns in the river. Copyright © 2009 John Wiley & Sons, Ltd.     

Erratum to: Flood Forecasting and Decision Making in the new Millennium. Where are We?

Water Resources Management -     

From Marrakech through The Hague to Kyoto: Has the Global Debate on Water Reached a Dead End?

Abstract

Although the first World Water Forum was held in 1997, realization by the world community of the vast array of problems facing the water sector dates back to the seventies. Indeed, the Mar del Plata Water Conference that was held in 1977 can be considered the first world water forum. Since that time, a series of international conferences, including the three world water forums that were held in Marrakech, The Hague, and Kyoto, have been organized to discuss the existing and emerging water problems. Such conferences and forums have debated the major issues regarding management and development of water resources, and have adopted a number of resolutions, declarations, and action plans. The debate on many of those issues has sharpened in recent years and the resolutions, declarations, and action plans have multiplied. This article discusses the basic elements of the debate and the areas of differences between the various groups, and assesses the efficacy and impact of the resolutions, declarations, and action plans adopted at those conferences.

This is the first of a two-part article, the second of which will be published in the next issue of this Journal.     

Water Use and Climate Stressors in a Multiuser River Basin Setting: Who Benefits from Adaptation?

Adapting to new climate conditions will require an intricate mix of knowledge, planning, coordination, and foresight. There is increasing sectoral evidence on the implementation of successful adaptation actions. However, the success of these actions when we consider the interdependencies among sectors remains debatable. This paper aims to assess who benefits from implementing adaptation options in a multiuser river basin to both climate-induced and demographic stress on water use. Our analysis relies on a hydro-economic model that considers two sets of water users: agriculture and urban households. We innovate in our modelling approach by analyzing and explicitly integrating the household-level economic behavior through its water demand. We assess the cross-user consequences of autonomous and planned adaptation actions. We provide insights into the different trade-offs at the basin level, demonstrating the compatibilities and divergences between agriculture and household-level water demand. We found different consequences of implementing either autonomous or planned adaptation measures. For instance, a decentralized scheme would drive negative implications for the entire basin, although the less water-intensive sector will be better off. On the other hand, different policy interventions would drive positive consequences for the entire basin, with the most water-intensive sector benefiting the most. These results highlight the distributional consequences across users of different adaptation measures.