Integrated Water Resources Management in the Sandougou Catchment Area(Senegal):Going beyond Soil Defence and Restoration(SDR)

The Sandougou River is the last major right bank tributary of the Gambia River.It has a catchment area of 11,668 km² and is located in Senegalese territory.The flow in this sloping basin(1‰)is favoured by the conservation of soils and vegetation.Since 1970,global rainfall trends(below the average of 800 mm)have shown a drought affecting the whole basin with an average deficit of 100 mm per year.In addition,erosion phenomenon combined with high rainfall intensities explains the rapid run-off.This constitutes a considerable loss of water resources,up to 20%in the Sandougou basin.In this rural area where primary activities predominate,anthropogenic pressure is considerable.Indeed,overexploitation of firewood,resulting from the strong dependence of local populations on this resource,is at the origin of deforestation in the Sandougou basin.Such a situation contributes to environmental degradation and also has repercussions on soil erosion.Erosion affects the water retention capacity of the soil making it more susceptible to extreme conditions such as drought.The impact of soil erosion on more remote sites is not always as apparent as the impact of erosion on the site itself.Sediment reaching watercourses can accelerate slope erosion,silt up drainage ditches and streams,silt up reservoirs,cover spawning areas and reduce water quality.Fertilizers frequently transported with soil particles can contaminate or pollute water sources.To cope with this dynamic,soil defence and restoration(SDR)techniques have long been considered as the solution to the problems.However,the multifaceted nature of environmental problems and their persistence leads to the consideration of a more holistic approach.In the Sandougou catchment area,the application of article R50 of the Senegalese Forestry Code,the implementation of planning tools(AP-IWRM),institutional development in the framework of integrated water resources management(IWRM)prove the interest of such an approach for the protection of water resources.

Improving Water Quantity and Quality Supply Security by Managed Artificial Recharge Technologies in the Lower Llobregat Aquifers Integrated into a Conjunctive Surface and Groundwater Management Scheme for Barcelona,Spain

The large concentration of human population,industry and services in the Metropolitan Area of Barcelona has to confront scarce water resources,serious seasonal and inter-annual variations and quality deficiencies in the sources.A large fraction of these water resources are in the medium-size Llobregat River basin and the remaining ones correspond to a surface water transfer,seawater desalination and wastewater reclamation.Groundwater dominated water resources availability before 1950.Afterwards,water supply has evolved progressively to integrated water resources management,which includes serious water quality concerns to deal with population density,river pollution,seawater intrusion in the main aquifer,and brine generation in the mid Llobregat basin due to old mining of saline minerals.The role of the alluvial aquifers has progressively evolved from being the main water source to reserve storage to cope with seasonal and drought water resources availability.River-enhanced recharge and artificial recharge are needed to assure enough groundwater storage before surface water becomes scarce and/or suffers a serious temporal loss of quality.Enhanced river recharge started in 1950.Treated river water injection in dual-purpose wells was put into operation in the early 1970s.Basin and pond recharge was added later,as well as a deep well injection barrier along the coast to reduce seawater intrusion and to allow increased groundwater abstraction in moments of water scarcity.There is a progressive evolution from solving water quantity problems to consideration of water quality improvement during recharge,with attention to emergent concern pollutants in river water and in reclaimed water to be considered for artificial recharge.Improvement of artificial recharge operation activities has been introduced and research is being carried out on the difficult behavior to degrade organic pollutants during infiltration and in the terrain.This paper presents the different activities carried out and presents the research activities,and comments on the economic,social and administrative issues involved as well.

Toward a socio-political approach to water management: successes and limitations of IWRM programs in rural northwestern China

In rural north-western China,the tension between economic growth and ecological crises demonstrates the limitations of dominant top-down approaches to water management.In the 1990s,the Chinese government adopted the Integrated Water Resources Management(IWRM)approach to combat the degradation of water and ecological systems throughout its rural regions.While the approach has had some success at reducing desertification,water shortage,and ecological deterioration,there are important limitations and obstacles that continue to impede optimum outcomes in water management.As the current IWRM approach is instituted through a top-down centralized bureaucratic structure,it often fails to address the socio-political context in which water management is embedded and therefore lacks a complete treatment of how power is embedded in the bureaucracy and how it articulates through economic growth imperatives set by the Chinese state.The approach has relied on infrastructure heavy and technocratic solutions to govern water demand,which has worked to undermine the focus on integration and public participation.Finally,the historical process through which water management mechanisms have been instituted are fraught with bureaucratic fragmentation and processes of centralization that work against some of its primary goals such as reducing uncertainty and risk in water management systems.This article reveals the historical,social,political,and economic processes behind these shortcomings in water management in rural northwestern China by focusing on the limitations of a top-down approach that rely on infrastructure,technology,and quantification,and thereby advances a more holistic,socio-political perspective for water management that considers the state-society dynamics inherent in water governance in rural China.

Watershed science:Linking hydrological science with sustainable management of river basins

Over the past decades,a number of water sciences and management programs have been developed to better understand and manage the water cycles at multiple temporal and spatial scales for various purposes,such as ecohydrology,global hydrology,sociohydrology,supply management,demand management,and integrated water resources management(IWRM).At the same time,rapid advancements have also been taking place in tracing,mapping,remote sensing,machine learning,and modelling technologies in hydrological research.Despite those programs and advancements,a water crisis is intensifying globally.The missing link is effective interactions between the hydrological research and water resource management to support implementation of the UN Sustainable Development Goals(SDGs)at multiple spatial scales.Since the watershed is the natural unit for water resources management,watershed science offers the potential to bridge this missing link.This study first reviews the advances in hydrological research and water resources management,and then discusses issues and challenges facing the global water community.Subsequently,it describes the core components of watershed science:(1)hydrological analysis;(2)water-operation policies;(3)governance;(4)management and feedback.The framework takes into account water availability,water uses,and water quality;explicitly focuses on the storage,fluxes,and quality of the hydrological cycle;defines appropriate local water resource thresholds through incorporating the planetary boundary framework;and identifies specific actionable measures for water resources management.It provides a complementary approach to the existing water management programs in addressing the current global water crisis and achieving the UN SDGs.

Bridging gaps between environmental flows theory and practices in China

In recent decades,a series of policies and practices for environmental flows(e-flows)have been implemented in China,with the sustainable development goal of balancing the utilization and protection of water resources among social,economic,and ecological needs.The aims of this study were to determine the main challenges and issues in e-flows implementation at different scales by analyzing policies and practices for eflows in China,and to propose some recommendations for bridging the gaps between the science and implementation of e-flows.The gaps between the science and implementation of e-flows were found after review of literature,policies,and practices,and it was found that ecological flow was a more widely used term by the government,rather than e-flows,in implementation.The plans and effects of e-flows implementation are discussed in this paper and challenges of e-flows implementation are recognized:(1)limited water resources and uneven spatial and temporal distribution,(2)a weak scientific basis for e-flows implementation,(3)poor operability of e-flows science,and(4)ineffective supervision and guarantee measures.The recommendations are(1)to strengthen the scientific foundation of e-flows,(2)to improve effectiveness in application of e-flows science,and(3)to propose operable and effective supervision and guarantee measures.This paper elaborates the current understanding of e-flows science and provides practical recommendations for implementing e-flows and for improving the effectiveness in e-flows implementation.To bridge the gaps between science and implementation of e-flows and improve the operability of policies in future practices,more scientific research on practices is recommended through adaptive management.

Upstream-downstream linkages of hydrological processes in the Himalayan region

Understanding the upstream-downstream linkages in hydrological processes is essential for water resources planning in river basins.Although there are many studies of individual aspects of these processes in the Himalayan region,studies along the length of the basins are limited.This study summarizes the present state of knowledge about linkages in hydrological processes between upstream and downstream areas of river basins in the Himalayan region based on a literature review.The paper studies the linkages between the changes in the physical environment of upstream areas(land use,snow storage,and soil erosion)and of climate change on the downstream water availability,flood and dry season flow,and erosion and sedimentation.It is argued that these linkages are complex due to the extreme altitudinal range associated with the young and fragile geology,extreme seasonal and spatial variation in rainfall,and diversity of anthropogenic processes.Based on the findings,the paper concludes that integrated systems analysis is required to understand the holistic complexity of upstream-downstream linkages of hydrological processes in the river basin context.The integrated land and water resources management(ILWRM)approach can be instrumental in developing adaptive solutions to problems and can also enable stakeholders of upstream and downstream areas with various interests and needs to work together for the better utilization and management of land and water resources.As a part of this,the specific circumstances of the upstream communities,who live in fragile and inaccessible mountain areas with limited resource opportunities,should be taken into account so that incentive mechanisms can be established to encourage and acknowledge their contribution.