Groundwater Risk Management Assessment in Arid Regions

Wadis are arid region drainage basins, mostly in the Quaternary depositions of different facies and grain size distributions depending on the paleogeologic environmental processes. Random and heterogeneous setup of the subsurface geological layer composition gives rather independent, haphazard and different aquifer numerical properties even along short distances. The aquifer storativity and transmissivity estimations from a set of wells provide spatial variability feature that can be captured by probability and statistical methodologies leading to risk assessment. Three methodologies are employed for the uncertainty assessments in this paper. The heterogeneity can be treated either through deterministic formulations by a set of assumptions or by statistical and probabilistic approaches giving way to risk assessments. They are the classical deterministic approach, statistical procedure that takes into consideration arithmetic average, standard deviation and correlation coefficient of hydrogeological variables and finally the probabilistic method with risk attachments. The first approach depends on the constant aquifer parameters or their arithmetic averages only. The second procedure considers the deviations (perturbations) from the arithmetic average and then various statistical parameters enter into the calculations. Finally, the last method considers the probability distribution function (pdf) of each hydrologic variable and their composition through specific groundwater storage capacity equation with risk levels at 10?% 25?%, 50?%, 75?%, 90?% and 95?%. The application of the methodology is presented for wadi Fatimah that lies in the central western part of the Kingdom of Saudi Arabia.     

Groundwater Management for Sustainable Development of Urban and Rural Areas in Extremely Arid Regions: A Case Study

In Saudi Arabia, the recharge to local and regional aquifers is mostly indirect, very limited and insignificant, especially with low annual precipitation. Most of the stored groundwater in local and regional aquifers is non-renewable fossil water. With rapid socio-economic developments and increasing population coupled with agricultural and industrial growth in the Kingdom, especially after the large increase in oil revenues after 1974, the water demands have increased drastically. By understanding the aquifer features, the country followed a planned approach based on controlling aquifer development and demand management to use its groundwater resources. The socio-economic developments in rural areas have been very pronounced. Corrective demand management measures including reduction in cultivated areas and modification in agricultural support policies in addition to the augmentation of water supplies by the reuse of treated wastewater have reduced the stress on groundwater. The establishment of a special Ministry for water and the adoption of a national water planning approach and the use of an integrated water resources management tool are expected to contribute effectively to the achievement of sustainable groundwater resources and the national interest of the country.     

Challenges for Sustainable Management of Groundwater Use in Bangkok,Thailand

An overview of groundwater development in Bangkok, Thailand, is provided and the paper highlights the environmental consequences of unplanned large-scale groundwater utilization. The effectiveness of the control measures adopted so far to address the issue of land subsidence is discussed. Recent initiatives and studies are analysed and the impediments to effective implementation of control measures are identified. Challenges faced by the Department of Groundwater Resources, which is responsible for groundwater development and management, are indicated. Recommendations are then put forward for improvement of the groundwater management system.     

Groundwater Rights and Legislation for Sustainable Development in Arid Regions: The Case of Saudi Arabia

The main objective of this article is to shed light on an important issue of water conservation-groundwater rights and legislation. Principles of groundwater rights are detailed and their applications to major aquifer systems, groundwater basins and wadis are discussed. Legislation and the clarification of water rights are vital for the sustainable development of groundwater. They are urgently needed in Saudi Arabia in particular and in all areas where demand exceeds supply. Legislation is one of the main pillars upon which any conservation policy is built. In this article a model is suggested for groundwater allocation in aquifers shared by more than one state.     

Challenges and Prospects of Sustainable Groundwater Management in the Indus Basin,Pakistan

In Pakistan, on-demand availability of groundwater has transformed the concept of low and uncertain crop yields into more assured crop production. Increased crop yields has resulted in food security and improved rural livelihoods. However, this growth has also led to problems of overdraft, falling water tables and degradation of groundwater quality, and yields generally remain well below potential levels. Over the last three decades, Pakistan has tried several direct and indirect management strategies for groundwater management. However the success has been limited. This paper argues that techno-institutional approaches such as introducing water rights, direct or indirect pricing and permit systems are fraught with difficulties in Pakistan due to its high population density and multitude of tiny users. Therefore there is a need to develop frameworks and management tools that are best suited to Pakistani needs. Pakistan should follow both supply and demand management approaches. For demand management, adoption of water conservation technologies, revision of existing cropping patterns and exploration of alternate water resources should be encouraged. For supply management, implementation of the groundwater regulatory frameworks developed by Provincial Irrigation and Drainage Authorities (PIDAs) and introduction of institutional reforms to enhance effective coordination between different organizations responsible for the management of groundwater resources should be given priority.     

A Suitable Tool for Sustainable Groundwater Management

Artificial recharge is used to increase the availability of groundwater storage and reduce saltwater intrusion in coastal aquifers, where pumping and droughts have severely impaired groundwater quality. The implementation of optimal recharge methods requires knowledge of physical, chemical, and biological phenomena involving water and wastewater filtration in the subsoil, together with engineering aspects related to plant design and maintenance operations. This study uses a novel Decision Support System (DSS), which includes soil aquifer treatment (SAT) evaluation, to design an artificial recharge plant. The DSS helps users make strategic decisions on selecting the most appropriate recharge methods and water treatment technologies at specific sites. This will enable the recovery of safe water using managed aquifer recharge (MAR) practices, and result in reduced recharge costs. The DSS was built using an artificial intelligence technique and knowledge-based technology, related to both quantitative and qualitative aspects of water supply for artificial recharge. The DSS software was implemented using rules based on the cumulative experience of wastewater treatment plant engineers and groundwater modeling. Appropriate model flow simulations were performed in porous and fractured coastal aquifers to evaluate the suitability of this technique for enhancing the integrated water resources management approach. Results obtained from the AQUASTRESS integrated project and DRINKADRIA IPA CBC suggest the most effective strategies for wastewater treatments prior to recharge at specific sites.     

Public Perceptions and Actions towards Sustainable Groundwater Management in the Pacific Northwest Region,USA

A 50-question survey was developed by the land grant universities in the Pacific Northwest to document public awareness, aptitudes, attitudes and actions toward water issues in the states of Alaska, Idaho, Oregon and Washington, USA. Demographic data were also collected about the survey respondents. The statistically designed survey was completed by over 50% of the 1800 residents who were solicited for the study. The public consider clean groundwater a high priority issue. Survey respondents currently consider groundwater quality to be good; however, most people are unaware of groundwater quantity issues. In the last 5 years, a majority of survey respondents have taken voluntary actions both to protect groundwater quality and to conserve the use of this resource. People want the government to focus more attention on groundwater issues; however, they are unwilling to pay increased taxes to achieve this end. Based on this survey, the land grant universities need to increase groundwater education programmes for the public using television, radio, newspapers and the Internet rather than by the traditional workshop delivery methods.     

Sustainable Development through Groundwater Management: A Case Study on the Barind Tract

Since its birth in 1985, the Barind Multi-purpose Development Project (BMDP) has become a model of a sustainable rural development project in Bangladesh. The project maintains technical soundness by ensuring a high level of water use efficiency and a minimum well spacing. The project runs on full operating and maintenance cost recovery basis, which is achieved through an innovative prepaid water coupon system and the associated command area development scheme. Its governance structure is democratic and participatory. The project has several environmental enhancement programmes such as water conservation, homestead and social forestry, promotion of integrated pest control, and farmers' training. In addition, it has adopted an integrated planning approach that incorporates extending rural electrification, building rural infrastructure and an array of other support programmes. As a result, the BMDP has emerged as a model of sustainable groundwater-based rural development initiative in Bangladesh.     

Cost-effective Approaches for Sustainable Groundwater Management in Alluvial Aquifer Systems

The consequences of unsustainable use of groundwater are becoming increasingly evident worldwide, particularly in developing nations. Groundwater management is a serious problem in many parts of the world. The prime concern is how to achieve groundwater sustainability. Artificial recharge techniques coupled with water harvesting hold a great promise for groundwater sustainability. The main intent of this paper is to highlight salient cost-effective and easy-to-use methods for augmenting groundwater resources in the alluvial hydrogeologic setting. Based on the intensive field investigation in a groundwater basin of Japan, three low-cost and easy-to-implement recharge techniques are suggested for alluvial aquifer systems, viz., augmentation of river flow, recharge through irrigation/drainage canals, and recharge from paddy fields. The source of recharge water for these recharge techniques is surface water supply. The efficacy of these methods or approaches has been demonstrated. It is emphasized that such cost-effective methods of groundwater recharge are key to sustainable groundwater management in both developing and developed countries. These methods must not be overlooked in the midst of sophisticated and highly expensive methods.     

Optimized Sustainable Groundwater Extraction Management: General Approach and Application to the City of Lucknow, India

In rapidly developing urban areas of emerging countries, increased water demand has led to enormous groundwater withdrawal, calling out for sustainable groundwater management. We suggest implementing a sustainable pumping rate concept based on numerical modeling of the managed aquifer. Sustainability is achieved by constraints regarding (1) a minimum groundwater discharge rate to gaining rivers (ecological constraint) and (2) a maximum drawdown along the city boundaries (social constraints) to prevent excessive groundwater depletion in the neighboring peri-urban and rural areas. The total groundwater extraction is maximized subject to these constraints, leading to specific extraction patterns throughout the city, depending upon the values set for the constraints. The optimization is performed by linear programming. For a given extraction rate, the two constraints can be traded off by the groundwater manager, causing different wells to be activated or deactivated. We demonstrate the applicability of the methodology by the example of the city of Lucknow, India, but it can be transferred to other cities facing conflicts of managing groundwater resources.     

Moving from Resource Development to Resource Management: Problems,Prospects and Policy Recommendations for Sustainable Groundwater Management in Bangladesh

Water Resources Management - Increased groundwater accessibility resulting from the expansion of deep and shallow tube wells helped Bangladesh attain near self-sufficiency in rice, with national...     

Simulation-Optimization Modelling for Sustainable Groundwater Management in a Coastal Basin of Orissa, India

The Balasore coastal groundwater basin of Orissa in eastern India is under a serious threat of overdraft and seawater intrusion. Two optimization models were developed in this study for the efficient utilization of water resources in Balasore basin during non-monsoon periods: (a) a non-linear hydraulic management model for optimal pumpage, and (b) a linear optimization model for optimal cropping pattern in integration with a calibrated and validated groundwater flow simulation model. Based on the simulation-optimization modeling results, optimal pumping schedules, cropping patterns, and corresponding groundwater conditions are presented for three scenarios viz., wet, normal and dry years. It was found that optimal pumping schedules and corresponding cropping patterns differed significantly under the three scenarios, and the groundwater levels improved significantly under the optimal hydraulic conditions compared to the existing condition. In dry years, the groundwater levels under the present pumping pattern and the optimal pumpage indicated that the non-monsoon pumpage should not exceed the optimal pumpage in the absence of remedial measures in the basin. It is concluded that in order to ensure sustainable groundwater utilization in the basin, the optimal cropping pattern and pumping schedule should be adopted by the farmers.     

Accounting for Climate Change and Drought in Implementing Sustainable Groundwater Management

Groundwater provides close to 40% of California’s overall water supply under average hydrologic conditions. It is a critical source of backup during drought when increased pumping occurs to compensate for reduced surface supplies and decreased soil moisture. The conundrum is that in regions of the state where groundwater dependence is already high and rates of recharge are low, over the long term the volume withdrawn, particularly during droughts, generally exceeds replenishment in many regions. The result is overdraft - ongoing declines in groundwater levels over the long-term. To facilitate the reduction or cessation of long-term groundwater overdraft, this paper proposes that sustainable groundwater management must include the development of a drought reserve. The reserve, ideally sourced, sited and used locally, would encompass sufficient water for use during a drought such that the increased withdrawals during a drought do not result in unrecoverable groundwater declines and concomitant negative impacts. The objective is to reduce vulnerability to the state’s periodic droughts, as opposed to mitigating seasonal variations in precipitation. This paper first summarizes the issues associated with developing drought reserves, and then examines in detail how two California groundwater management agencies approach establishing and implementing a drought reserve.     

Problems of Sustainable Groundwater Management in an Area of Over-exploitation: The Upper Guadiana Catchment,Central Spain

The problem of achieving sustainable groundwater management in areas of over-exploitation is examined by using the upper Guadiana basin in central Spain as an example. Here, since the early 1970s, high rates of abstraction to provide water for irrigation have lowered the water table by up to 50 m, causing the main rivers to run dry and an internationally renowned wetland to become desiccated. Conflict between farmers, regulators and conservationists has created a difficult problem that legal action, subsidies and engineering solutions have so far failed to combat. Faced with conflicting demands, it is suggested that integrated catchment management provides the best way forward. The various issues that need to be addressed with this type of management system are outlined.     

干旱区流域可持续水资源管理量化研究方法及应用

近年来,干旱地区水资源的开发成本在不断增加,需要不断提高水资源管理开发的效益和效率,使单位水的产出达到最优。文章介绍干旱区可持续水资源管理绩效综合评价指标体系的基础上,对指标权重进行了确认并给出了综合定量评价模型,同时运用相对变化指数法、加权综合指数法对研究区可持续水资源管理绩效进行了定量研究。     

Approach and Methods for the Assessment of Sustainable Groundwater Management in the Rhine–Neckar Region,Germany

The Rhine–Neckar Region is a densely populated and highly industrialized region with competing interests and strong pressure on the availability of high-quality groundwater. The increasing pressure on both groundwater quantity and quality is due to the high demand of people and industry for water and to pollution by industrial spills as well as agricultural activities. This led to a systematic investigation of the groundwater management of the multilayered transboundary aquifer and the question of its sustainability. A combination of intensive groundwater model simulations, scenario analyses and stakeholder participation proved to be a promising approach to tackle the complex issues of groundwater management. Long-term consequences, changes in natural processes and ecosystem needs were particularly considered. Specific recommendations for improved groundwater management in this region were formulated. The study also shows the need for a general approach towards the assessment of sustainable groundwater management.     

Sustainable,Just, Equal,and Optimal Groundwater Management Strategies to Cope with Climate Change: Insights from Brazil

Water Resources Management - This paper applies optimal-control theory to develop groundwater exploitation strategies that account for potential climate change patterns in Brazil. Numerical...     

Contrasting stream stability characteristics in adjacent urban watersheds: Santa Clara Valley,California

A comparative study of two adjacent stream channels in the Santa Clara Valley region of California provided an opportunity to study the relative effects of multi‐faceted watershed‐urbanization impacts on channel evolution and stability. Berryessa Creek (15.5 km²) and Upper Penitencia Creek (61.3 km²) have similar intrinsic watershed characteristics; however, urbanization processes have imposed distinctly different evolutionary trends in each watershed. The influences of drainage network manipulation, hydrologic routing and engineering infrastructure has resulted in Upper Penitencia Creek remaining relatively stable throughout the course of urbanization, while Berryessa Creek has experienced system‐wide channel instability problems. This study enumerates the many anthropogenic impacts and provides insight into basin alterations that can have either positive or negative feedbacks in maintaining or degrading channel stability throughout the course of urbanization. Results show that infrastructure that disrupts the bed material sediment continuity (such as large drop structures or sedimentation ponds) generate long‐term downstream channel instabilities leading to channel degradation and continued maintenance. Off‐line flow diversions (in this study percolation ponds) that do not disrupt bed material transport can emulate pre‐urbanization conditions offsetting channel degradation resulting from changes in hydrology. This study also demonstrates the degradational responses of a stream due to losses in riparian vegetation from water table lowering transforming a perennial stream into an ephemeral stream resulting in increased bank instability. The importance of maintaining floodplains for flood access and channel stability has also been identified and compared to conditions of channel encroachment to facilitate maintenance, which have further exacerbated downstream channel degradation, long‐term channel maintenance and dredging. Copyright © 2009 John Wiley & Sons, Ltd.     

泾惠渠灌区干旱时段内的地下水动态

泾惠渠灌区是陕西重要的农业生产基地,研究灌区干旱时段的地下水动态对灌区农业生产具有重要意义。通过灌区多年的降水量资料,采用Z指数法选取了灌区的典型干旱时段,然后选取灌区内的典型观测井位分析了其干旱时段内地下水动态特征。     

Sustainable Groundwater Allocation in the Great Lakes Basin

Outdated groundwater allocation policies have resulted in unrestrained abstraction of groundwater in the Great Lakes Basin. Continuing on this course will lead to more frequent conflicts and further degradation of the Basin's ecosystem. Alternative approaches must focus on achieving sustainable groundwater allocation. The authors present two alternative institutions, local collaborative planning for groundwater allocation, and a regional watershed board. Collaborative institutions responsible for local groundwater planning should be established according to practical geographical units, have access to sound scientific information, utilize adaptive management and engage in open deliberation. The regional watershed board should establish a comprehensive and unified inventory of all groundwater resources in the Basin, designate critical groundwater areas, monitor groundwater management by respective jurisdictions, and make recommendations on best practices.