11-20 of 342 Results

Article

The Development Path of Urban Water and Sanitation Tariffs and Subsidies: A Conceptual Framework  

Dale Whittington, Marcus Wishart, David Kaczan, Hua Wang, Xiawei Liao, and Si Gou

The provision of universal, high-quality piped water and sanitation services on a financially sustainable basis continues to elude many urban areas globally. Water services suffer from political, technical, and financial “disequilibria,” in which governments are challenged to improve services, households are unwilling or unable to pay to cover the increased costs associated with those services, and both production and consumption efficiency remains low due to insufficient capital investment, low operating budgets, and poorly designed tariffs. Cities typically move along a water development path from low- to high-quality service provision, with movement between phases facilitated by shifts in these disequilibria. In the first phase, water supply coverage increases but quality of service and efficiency of consumption and production stagnates, trapped by insufficient government transfers and low tariffs. In the second phase, economic growth facilitates increased revenues, allowing for investments in service quality and increasing access to improved sanitation. Production efficiency improves, but consumption efficiency remains low due to weak price signals and poorly targeted subsidies, and environmental quality often degrades. In the third phase—which remains aspirational for many cities—governments and citizens demand improved environmental quality as well as improved service quality. Investments are made to improve the resilience of supply, and subsidies are more carefully targeted toward the poor. China demonstrates many of these patterns, with variation across cities reflecting different levels of development. There are, however, some differences that are a consequence of the country’s centrally planned economy prior to 1978. Reforms underway in China highlight the challenges of achieving this “third phase” urban water policy. These include revisions to the existing increasing block tariffs to improve financial sustainability, increased use of information provision to improve consumption efficiency, and asset management and investment planning that weighs the benefits and costs of new capital investments in the context of climate change.

Article

Ecosystem Benefits of Large Dead Wood in Freshwater Environments  

Ellen Wohl

Large wood in freshwater environments is downed, dead wood pieces in river channels, floodplains, wetlands, and lakes. Large wood was historically much more abundant in freshwaters, but decades to centuries of deforestation and direct wood removal have decreased wood loads—volumes of large wood per unit area—in freshwaters around the world. The widespread public perception that large wood is undesirable in freshwater environments contrasts with scientific understanding of the beneficial effects of large wood. Large wood tends to increase the spatial heterogeneity of hydraulics, substrate, channel planform, and the floodplain and hyporheic zone in rivers. This equates to greater habitat diversity and refugia for organisms, as well as energy dissipation and storage of materials during floods, which can increase the resilience of the river to disturbances such as wildfire, drought, and flooding. Similarly, wood in lakes increases lakeshore and lakebed heterogeneity of hydraulics, substrate, habitat, nutrient uptake, and storage of particulate organic matter and sediment. Large wood in rivers and lakes provides an array of vital ecosystem functions, and both individual species and biotic communities are adversely affected by a lack of wood in rivers and lakes that have been managed in a way that reduces wood loads. River and lake management are now more likely to include protection of existing large wood and active reintroduction of large wood, but numerous questions remain regarding appropriate targets for wood loads in different environmental settings, including potential threshold wood loads necessary to create desired effects. Large wood can also directly and indirectly enhance carbon storage in freshwater environments, but this storage remains poorly quantified.

Article

International Water Law and Its Developing Role in Conflict and Cooperation Over Transboundary Water Resources  

Susanne Schmeier

International water law plays a key role in guiding states’ behavior over water resources they share. Substantive and procedural principles provide an ex ante framework based on which states can interact in a manner that prevents or mitigates potential conflicts and fosters cooperation and its benefits while supporting the sustainable use and management of these transboundary resources. Through the international water law regime, cooperation has largely prevailed over conflict in the world’s transboundary basins. Nonetheless, international water law—and thus also its role in conflict prevention and cooperation promotion—faces various challenges as populations and economies grow, the climate changes, and states seem to increasingly value short-term unilateral considerations over long-term multilateralism gains. This will challenge key principles, such as the principle of equitable and reasonable utilization and the principle of no significant harm, and their implementation in different basins, possibly triggering new disagreements between riparian states. It will therefore be important for international water law to remain adaptive to change and ensure the long-term cooperative and sustainable governance of water resources shared between states.

Article

Water Risks and Rural Development in Coastal Bangladesh  

Sonia Hoque and Mohammad Shamsudduha

Rural populations in river deltas experience multiple water risks, emerging from intersecting anthropogenic and hydroclimatic drivers of change. For more than 20 million inhabitants of coastal Bangladesh—living on the lower reaches of the Ganges–Brahmaputra–Meghna mega-delta—these water risks relate to access to safe drinking water, management of water resources for farm-based livelihoods, and protection from water-related hazards. To address these risks, water policies in the 20th century emphasized infrastructure development, ranging from embankments for flood protection to handpumps for rural water supply. However, interventions designed to promote aggregate economic growth often resulted in sociospatial inequalities in risk distribution, particularly when policy-makers and practitioners failed to recognize the complex dynamics of human–environment interactions in the world’s most hydromorphologically active delta. In Bangladesh’s southwestern region, construction of the polder system (embanked islands interlaced with tidal rivers) since the late 1960s has augmented agricultural production by protecting low-lying land from diurnal tidal action and frequent storm surges. However, anthropogenic modification of the natural hydrology, emulating the Dutch dyke system, has altered the sedimentation patterns and resulted in severe waterlogging since the 1980s. Contrary to their intended purpose of keeping saline water out, the polders also facilitated growth of export-oriented brackish water shrimp aquaculture, resulting in widespread environmental degradation and social inequalities from shifting power dynamics between large and small landholding farmers. Throughout the 1990s, there were several incidences of violent conflicts between the local communities and government authorities, as well as between different farmer groups. Waterlogged communities demanded to revert to indigenous practices of controlled flooding. Despite being formally adopted as a policy response, the implementation of tidal river management by the government has only been partially successful owing to bureaucratic delays, unfair compensation, and design flaws. Similarly, antishrimp movements gained momentum in several polders to ban the deliberate flooding of cropland with saline water. These narratives of conflict and cooperation demonstrate the complexities of policy outcomes, the unequal distribution of water risks, and the need to integrate local knowledge in decision-making. Social and spatial inequalities are also prevalent in access to safe drinking water owing to heterogeneity in groundwater salinity and infrastructure investments. Public investments are skewed toward low-salinity areas where tubewells are feasible, while high-salinity areas are often served by uncoordinated donor investments in alternative technologies, such as small piped schemes, reverse osmosis plants, and pond sand filters, and household self-supply through shallow tubewells and rainwater harvesting. These struggles to meet daily water needs from multiple sources pose uncertain and unequal water quality and affordability risks to coastal populations. The path-dependent sequences of infrastructure and institutional interventions that shaped the development trajectory of coastal Bangladesh exemplify the complexities of managing water risks and varied responses by public and private actors. While structural solutions still dominate the global water policy discourse, there is increased recognition of the nonlinearity of risks and responses, as well as the need to incorporate adaptive decision-making processes with room for social learning and uncertainties.

Article

Ecosystem Services into Water Resource Planning and Management  

Phoebe Koundouri, Angelos Alamanos, Kostas Dellis, Conrad Landis, and Artemis Stratopoulou

The broad economic notion of ecosystem services (ES) refers to the benefits that humans derive, directly or indirectly, from ecosystem functions. Provisioning ES refer to human-centered benefits that can be extracted from nature (e.g., food, drinking water, timber, wood fuel, natural gas, oils, etc.), whereas regulating ES include ecosystem processes that moderate natural phenomena (pollination, decomposition, flood control, carbon storage, climate regulation, etc.). Cultural ES entail nonmaterial benefits accruing to the cultural advancement of people, such as the role of ecosystems in national and supranational cultures, recreation, and the spur of knowledge and creativity (music, art, architecture). Finally, supporting ES refer to the main natural cycles that nature needs to function, such as photosynthesis, nutrient cycling, the creation of soils, and the water cycle. Most ES either depend on or provide freshwater services, so they are linked to water resources management (WRM). The concept of ES initially had a pedagogical purpose to raise awareness on the importance of reasonable WRM; later, however, it started being measured with economic methods, and having policy implications. The valuation of ES is an important methodology aimed at achieving environmental, economic and sustainability goals. The total economic value of ecosystems includes market values (priced) as well as nonmarket values (not explicit in any market) of different services for humanity’s benefit. The valuation of ES inherently reflects human preferences and perceptions regarding the contribution of ecosystems and their functions to the economy and society. The ES concept and associated policies have been criticized on the technical weaknesses of the valuation methods, interdisciplinary conflicts (e.g., ecological vs. economic perception of value), and ethical aspects on the limits of economics, nature’s commodification, and its policy implications. Since valuation affects the incentives and policies aimed at conserving key ES, e.g., through payment schemes, it is important to understand the way that humans decide and develop preferences under uncertainty. Behavioral economics attempts to understand human behavior and psychology and can help to identify appropriate institutions and policies under uncertainty that enhance ecosystem services that are key to WRM.

Article

The Economic Value of Water  

Michael Hanemann and Dale Whittington

In economics, the value of an item—including water—to a person is defined as the most of something else of value (typically money, but sometimes time) the person is willing to give up to obtain that item (willingness to pay) or the minimum compensation the person would want to receive in exchange for forgoing the item (willingness to accept). These are measures of gross value; they are in principle quantitative; and they are subjective and idiosyncratic to the individual and the circumstances. The economic value of an item is not measured by its price. It is likely to vary with the amount of the item and should not be taken as a constant. A core conceptual distinction is between use value and nonuse value. A person’s use value for an item is the value that she places on the item from motives connected with the use of the item by someone, whether her own use or that of someone else. Nonuse value is the value she places on an item from motives not directly connected with the use of that item by anybody in any tangible way. For example, a person may value water to drink (a use value), but he may also value having water remain in its natural state (a nonuse value). Consumptive uses are use values, but nonconsumptive uses can also be use values (e.g., swimming in a lake). Other conceptual distinctions include that between wet water and paper water (water that exists on paper but is not actually accessible or usable), and that between raw water alone versus water accompanied by the infrastructure necessary to store it and convey it so as to make it available for use.

Article

The History of Synoptic Meteorology in the Age of Numerical Weather Forecasting  

Kristine C. Harper

Despite some early attempts in the 19th century, national weather services did not regularly create forecasts for public consumption until the early 20th century, and many of those were based on a handful of surface observations of dubious quality. With the invention of the balloon-borne radiosonde in the 1930s, upper-air observations became more common, and knowledge of upper-level processes was melded into forecasting practice. World War II brought its own challenges and opportunities, expanding the number of trained meteorologists worldwide, establishing many new observing stations in tropical and high-latitude locations, and opening the possibility of using radar to identify short-range severe weather. But the big change was the development of digital electronic computers, and with them the opportunity to calculate the weather. The first efforts were marginal at best, but international teams in the United States and Sweden continued their efforts, and by the late 1950s, midatmospheric prognosis charts were being transmitted to forecast offices, which would prepare the final local forecasts. Unfortunately for the synoptic forecasters in the field offices, the new objective numerical weather prediction (NWP) products were not comparable to the old subjective forecast charts that they had used for years. The resulting push and pull between the atmospheric modelers and the synoptic meteorologists ultimately changed both groups: the atmospheric modelers used forecaster feedback to upgrade the models, and the synoptic meteorologists learned to use the objective forecasts. The anticipated improvements in weather forecasting, however, did not follow immediately. As the decades passed, computing power increased and the introduction of satellites with multiple specialized sensors, purpose-built weather radar, and other remote sensing devices increased the availability of ground and upper-air data. As a result, more variables and the physics that defined them were added to NWP models, and the resulting products changed the way synoptic meteorologists made their forecasts, even if they did not change their feel for the atmosphere. Those changes continued into the 21st century, fueling the desire for specialized forecasts from multiple interest groups and the public’s desire for accurate, up-to-the-minute weather forecasts that extend up to 2 weeks into the future.

Article

Environmental Policy and the Double Dividend Hypothesis  

Antonio M. Bento

Since the 1990s, the so-called double-dividend debate—that is, the possibility that swaps of newly environmental taxes for existing distortionary taxes such as taxes on labor or capital could simultaneously improve environmental quality and reduce the distortionary costs of tax system—has attracted the attention of policymakers and academics. And while prior to the 1990s environmental economics as a field was not ready to inform this debate, scholars quickly moved to incorporate insights of the theory of second-best from public economics to inform the discussion. The result was a substantial advancement of the field of environmental economics, with the evaluation of the welfare effects of alternative policy instruments relying on general equilibrium models with pre-existing distortions. Initially, scholars casted substantially doubt on the prospects of a double dividend, and suggested that environmental tax reforms would not reduce the distortionary costs of the tax system. This is because studies documented that the tax-interaction effect dominated the revenue-recycling effect. That is, newly environmental taxes interact with pre-existing distortions in labor markets. And even when the revenues of environmental taxes are used to cut the rate of the labor tax, the environmental tax reform exacerbates, rather than alleviate, pre-existing distortions in labor markets. Throughout the 2000s and in more recent decades, the literature has documented many instances where a double dividend is more likely to exist, including in the context of developing countries.

Article

Hedging and Financial Tools for Water Management  

C. Dionisio Pérez-Blanco

The management of risky water episodes entails a comprehensive set of instruments that can be broadly divided into two groups: damage prevention and damage management. Damage prevention instruments aim at negating or minimizing the economic damage of water scarcity and water extremes, and they include hard and soft engineering, information and awareness campaigns, and regulations and economic incentives. Damage management instruments aim at compensating damages and facilitating recovery, and they include tort law and hedging and financial tools. The growing interconnections and cascading uncertainties across coupled human and water systems make it increasingly challenging to comprehensively predict and anticipate expected damages from water scarcity and extremes, which is giving higher prominence to the management of damages, notably through hedging and financial tools. Hedging and financial tools are a risk transfer mechanism by which a potential future damage is transferred from one party to another, typically in exchange of a pecuniary compensation (risk premium), albeit they can be also freely provided (e.g., state aid). Hedging and financial instruments are varied and include futures, options, insurance, self-capitalization, reinsurance, private actions such as charities or nongovernmental organizations, state aid, and solidarity funds. The first section of this document discusses the political context for disaster risk reduction efforts at an international level and provides key definitions. The second section presents a taxonomy for hedging and financial instruments; assesses their strengths and weaknesses, performance, and market penetration levels; and critically reviews reform propositions in the literature toward increasing their performance and adoption. The third section discusses the interconnections between hedging and financial tools and damage prevention tools, as well as how their design can enhance each other’s performance. The last section discusses barriers and enablers for the adoption of hedging and financial tools.

Article

Machine Learning Tools for Water Resources Modeling and Management  

Giorgio Guariso and Matteo Sangiorgio

The pervasive diffusion of information and communication technologies that has characterized the end of the 20th and the beginning of the 21st centuries has profoundly impacted the way water management issues are studied. The possibility of collecting and storing large data sets has allowed the development of new classes of models that try to infer the relationships between the variables of interest directly from data rather than fit the classical physical and chemical laws to them. This approach, known as “data-driven,” belongs to the broader area of machine learning (ML) methods and can be applied to many water management problems. In hydrological modeling, ML tools can process diverse data sets, including satellite imagery, meteorological data, and historical records, to enhance predictions of streamflow, groundwater levels, and water availability and thus support water allocation, infrastructure planning, and operational decision-making. In water demand management, ML models can analyze historical water consumption patterns, weather data, and socioeconomic factors to predict future water demands. These models can support water utilities and policymakers in optimizing water allocation, planning infrastructure, and implementing effective conservation strategies. In reservoir management, advanced ML tools may be used to determine the operating rule of water structures by directly searching for the management policy or by mimicking a set of decisions with some desired properties. They may also be used to develop surrogate models that can be rapidly executed to determine the optimal course of action as a component of a decision-support system. ML methods have revolutionized water management studies by showing the power of data-driven insights. Thanks to their ability to make accurate forecasts, enhanced monitoring, and optimized resource allocation, adopting these tools is predicted to expand and consistently modify water management practices. Continued advancements in ML tools, data availability, and interdisciplinary collaborations will further propel the use of ML methods to address global water challenges and pave the way for a more resilient and sustainable water future.