Efficient Water Allocation and Water Conservation Policy Modeling in the Aral Sea Basin

Increasing water demand in the Aral Sea basin (ASB) challenges policy makers to implement in-time and effective water management measures to mitigate both the on-going and upcoming water crisis in the region. This study examines three important options for addressing the core reasons of aggravated water (ab)use in the ASB. In the first option, sectoral transformations (e.g., economic restructuring) are considered by prioritizing economic activities with relatively high economic growth impacts and low water consumption requirements. In the second option, it is assessed to replace the current administrative water management institutions with more effective market-based water allocation institutions to encourage cooperation among regional water users for attaining optimal basinwide benefits. In the third option, technological and infrastructural improvements are evaluated following an increased efficiency of the irrigation systems and building reservoirs in the upper reaches of the rivers to regulate river flow. The economic restructuring option was analyzed by ranking all economic sectors based on their sustainable economic growth potentials using an environmentally extended input-output model. The forward and backward linkages and the total (direct and indirect) water requirements of the different economic activities were estimated and compared. The results indicated that water demand in the ASB can be reduced by decreasing the production of the water intensive sectors such as agriculture in favor of the development of less water demanding, non-agricultural sectors. Potential effects of replacing the traditional administrative water allocation system with market-based water allocation approaches were examined through an aggregated hydro-economic model. Substantial basinwide economic gains appeared feasible when the trade of water rights among all irrigation zones was allowed in each river basin (the Amu Darya or Syr Darya). Total benefits under restricted water rights trading by permitting the trade only among the regions located within each upstream, midstream, and downstream sub-basins (catchments) is lower than the total economic gains of unrestricted water rights trading but was still higher than total benefits of the option without trading. The results indicated that the availability of additional annual gains ranged $373–476 million USD depending on water availability under an inter-catchment (unrestricted) water trading system. Similarly, additional annual gains of$ 259–339 million USD were predicted under intra-catchment (restricted) water trading. Results also showed that transaction costs of more than $0.05 USD per m3 of water use rights eliminate the potential benefits of a water trading option. Technical improvements to raise the efficiency of water use and water coordination were analyzed through a disaggregated hydro-economic model. Substantial benefits can be expected from improving irrigation (conveyance and water application) efficiencies in the ASB. According to the results, total basinwide benefits can increase by 20% to 40% depending on basinwide water availability when irrigation system efficiencies are optimized across the basin. The findings also showed that construction of upstream reservoirs as intensely debated by up- and downstream countries in Central Asia does not considerably influence the irrigation water availability if these reservoirs are operated with the objective of providing optimal basinwide benefits. Yet, the risks of flooding related to natural and political calamities and reduced downstream water availability during the period of filling the reservoirs should be evaluated further for a more comprehensive assessment of the infrastructural developments. High risks of using upstream reservoirs as a tool of geopolitical influence and consequent damage on downstream irrigation and environmental systems should not be forgotten as well.Modellierung von Strategien zur effizienten Allokation und Schonung von Wasserressourcen im Einzugsgebiet des Aralsees Im Einzugsgebiet des Aralsees (ASB) stellt der steigende Wasserbedarf eine Herausforderung an die Entscheidungsträger dar, zeitnah Maßnahmen für eine effiziente Wasserbewirtschaftung einzuführen, um die derzeitige und zukünftige Wasserkrise in der Region zu entschärfen. Diese Studie untersucht drei wichtige Ansätze, um die grundlegenden Ursachen der sich verschärfenden Wasserbewirtschaftungsprobleme im ASB zu bearbeiten. Die erste Option ist die sektorale Transformation (ökonomische Neuordnung), bei der man wirtschaftliche Aktivitäten mit hoher Priorität versieht, die einen relativ hohen Impuls auf das Wirtschaftswachstum ausüben und einen niedrigen Wasserverbrauch erfordern. Die zweite Option besteht darin, die bürokratischen Wassermanagement-Institutionen durch effektivere Markt-basierte Wasserallokations-Institutionen zu ersetzen, die die Zusammenarbeit zwischen regionalen Wassernutzern fördern, um in Bezug auf das gesamte Einzugsgebiet Vorteile zu erzielen. Die dritte Option beinhaltet die Verbesserung der Effizienz der Bewässerungssysteme und den Bau von Speichern zur Regulierung des Abflusses an den Oberläufen der Flüsse. Die Möglichkeit der ökonomischen Restrukturierung wurde mit Hilfe eines auf die Umweltfaktoren ausgeweiteten Input-Output Modells analysiert, so dass im Ergebnis alle ökonomischen Sektoren im Hinblick auf ihren potenziellen Beitrag zu einem nachhaltigen Wirtschaftswachstum beurteilt und in eine Rangliste gebracht wurden. Hierfür wurden Vorwärts- und Rückwärtsverknüpfungen und die gesamten (direkten und indirekten) Wasserbedarfswerte der verschiedenen wirtschaftlichen Aktivitäten geschätzt und miteinander verglichen. Die Ergebnisse zeigten, dass der Wasserbedarf im ASB reduziert werden kann, indem die Produktion wasserintensiver Sektoren wie Landwirtschaft verringert wird, während die Entwicklung weniger wasserintensiver Sektoren außerhalb der Landwirtschaft gefördert wird. Mit einem aggregiertem hydro-ökonomischen Modell wurden potenzielle Auswirkungen untersucht, die mit dem Ersetzen des traditionellen administrativen Wasserallokations-System durch Markt-basierte Wasserallokation erzielt werden können. Bedeutende ökonomische Gewinne im gesamten Einzugsgebiet sind erreichbar, wenn der Handel von Wasserrechten zwischen allen Bewässerungszonen in jedem der Einzugsgebiete (Amu Darya oder Syr Darya) erlaubt wurde. Die Begrenzung des Handels von Wasserrechten auf jeweils Untereinheiten der Einzugsgebiete (oberer, mittlerer, unterer Teil) führte zu einem Gesamtgewinn, der zwar geringer ausfiel als im Fall des unbegrenzten Handels aber höher war als bei der Option ohne Wasserhandel. Die Ergebnisse zeigen ein Potential von zusätzlichen jährlichen Gewinnen zwischen 373 bis 476 Millionen USD durch den Handel mit Wassernutzungsrechten im gesamten Einzugsgebieten (zwischen den Untereinheiten) in Abhängigkeit von der Wasserverfügbarkeit. Gleichermaßen ergeben sich zusätzliche Erträge von 259 bis 339 Millionen USD durch den Handel innerhalb von Untereinheiten desEinzugsgebietes. Weiterhin zeigen die Ergebnisse, dass Transaktionskosten von über 0.05 USD/m3 pro Einheit gehandelter Wasserhandelsrechte die potenziellen Vorteile der Wasserhandelsoption eliminieren würden. Technische Ansätze zur Verbesserungen der Effizienz der Wassernutzung und -koordination wurden mit einem dis-aggregierten hydro-ökonomischen Modell analysiert. Erhebliche Vorteile werden von der Verbesserung der Bewässerungswirkungsgrade (Bewässerungsnetz und Feldebene) im ASB erwartet. Aufgrund der Ergebnisse lässt sich der Gewinn im gesamten Einzugsgebiet um 20 bis 40% steigern (in Abhängigkeit von der Wasserverfügbarkeit), wenn die Bewässerungswirkungsgrade im gesamten Einzugsgebiet optimiert würden. Weiterhin belegen die Ergebnisse, dass die Konstruktion von Speicher an den Oberläufen der Flüsse (wie derzeit intensiv zwischen Ober- sowie Unterliegerstaaten in Zentralasien diskutiert) die Verfügbarkeit von Bewässerungswasser in der Region nicht erheblich beeinträchtigt, wenn diese Speicher unter der Zielvorgabe optimaler Einzugsgebiets-weiter Vorteile betrieben werden. Jedoch sollten mögliche Überflutungsrisiken durch Erdbeben und politische Instabilitäten sowie die verringerte Wasserverfügbarkeit flussabwärts während der Periode der Füllung der Speicher weiterführend untersucht werden, um eine fundierte Bewertung dieser Infrastrukturmaßnahmen zu ermöglichen. Es sollte nicht vernachlaessigt werden, dass die hohen Risiken von Speichern in oberen Bereichen der Einzugsgebiete durch die Nutzung als Instrumente geopolitischer Einflussnahne und aufgrund von Folgen fuer unterliegende Bewaesserungsgebiete sowie Oekoststeme die Vorteile der Speicher bei der infratsrukturellen Entwicklung eliminieren koennen

Enabling Environment for Waste and Wastewater Recycling and Reuse Options in South Asia: the case of Sri Lanka

Mismanagement of waste and wastewater is a key reason behind the continuing environmental pollution and degrading livelihoods across the developing countries of South Asia such as Sri Lanka. Recovering nutrients and energy from waste and wastewater streams can not only address the challenging waste and wastewater management problems but also considerably substitute the imports of chemical fertilizers and fossil fuels. Considering these environmental and economic benefits of waste and wastewater recycling, this study aims at assessing investment climate for a broader implementation of recycling technologies such as composting, biogas generation, and electricity production through incineration process. For this purpose, a wide range of methods were implemented including a detailed review of scientific literature, laws and reports by governmental agencies, as well as key informant interviews and focus group discussions. For assessing technical potential of recovering nutrients from waste streams a simulation model was applied. As results indicated, since waste generation and thus potential for nutrient recovery is high in urban areas, while demand for recovered nutrients is much higher in rural areas, interregional trade of the recovered nutrients would considerably contribute to reducing the shortage of fertilizers, improving food security, and increasing export incomes in Sri Lanka. Recovering nutrients from recycling only half of total organic waste and wastewater may allow for meeting agricultural demands for phosphorus and potassium, and supply 75% of nitrogen requirements at the national level. The government would need to be the main facilitator of the change through improving the accounting and planning in the system, establishing effective institutional and regulatory frameworks, providing financial incentives for the implementation of the recycling technologies, and supporting educational programs for raising the environmental consciousness

Potentials of Waste and Wastewater Resources Recovery and Re-use (RRR) Options for Improving Water, Energy and Nutrition Security

Under increasing demand for water, fertilizer and energy, waste and wastewater treatment can be potential options for considerably enhancing not only the supply of these valuable economic assets but also for improving sanitation and ecological conditions. Effluents and treated wastewater are important for meeting water demands for agricultural irrigation, landscape irrigation, and environmental system enhancement. Fertilizer and nutrients recovered though recycling organic waste and filtering wastewater, or embedded in effluents can be essential inputs for increasing crop biomass, timber output, and production of aquatic crops and marine species such as fish. Similarly, energy recovered from waste and wastewater recycling (including dry manure for cooking and heating) is important for enhanced energy supply especially in remote rural areas of the developing countries. Yet, the utilization of the waste and wastewater resources for additional gains should consider the accepted safety measures in order to prevent environmental and health risks. Focusing on potential benefits from resources recycling and recovery yet being cautious on their external effects, this review critically assesses the available waste and wastewater treatment options, and their economic, environmental and health benefits and risks

The Effect of Energy Constraints on Water Allocation Decisions: The Elaboration and Application of a System-Wide Economic-Water-Energy Model (SEWEM)

Worldwide, demand for water, energy, and food are on the rise due to population and industrial growth. Because of such increasing demands and in spite of the limitedness of key resources, more efficient ways to meet these demands become obligatory. Especially considering the multiple interlinkages between water, energy, and food/livelihood systems, an integrated management of key resources such as water, land, and energy deems essential for realizing synergetic efficiencies, for consistent policy decisions, and for sustainable development, in particular across the river basins of the world. Therefore, the general framework of a system-wide economic-water-energy model (SEWEM), which is applicable across river basins and adjustable to different spatial scales such as sub-catchments, is presented here to meet the demands for an effective analytical tool in dealing with water-energy-food/livelihood nexus challenges. Previous hydro-economic models often ignored energy requirements, for instance, for irrigation water supply, as well as energy supply constraints, which recurrently might have led to an overestimation of the optimal levels of ground and surface water uses. The SEWEM was developed to address this gap and analyze how optimal levels of surface and groundwater uses, as well as on irrigation and power production benefits, change in response to the consideration of energy supply constraints and energy requirements for water pumping and other agricultural production operations. This is illustrated for the case of the Aral Sea Basin (ASB) in Central Asia, where surface and groundwater supplies heavily depend on pumping and thus on energy availability. The findings underlined the overestimations of optimal water uses by a hydro-economic model that neglects energy constraints. Moreover, geographical conditions have affected the changes in optimal ratios of surface and groundwater uses and water distributions across the river basin when energy restrictions are taken into account. The results confirmed the importance of the consideration of energy constraints for the assessment of optimal water and land uses, and the essential role of an integrated analysis of water, energy, and food/livelihood systems for better-informed policy-making. Despite the added value of the SEWEM that can consider energy system constraints, further fine-tunings would make it even more relevant for addressing additional questions related to basin management. For example, improvements can be expected through considering the system dynamics, ecological aspects, income distribution effects, trade relationships, and institutional restrictions