Environmental and Resource Costs Under Water Scarcity Conditions: An Estimation in the Context of the European Water Framework Directive

The European Water Framework Directive (WFD) requires the good ecological status of surface water bodies, which implies the improvement of both their physicochemical condition, as well as their flow and continuity. The WFD prescribes the assessment of environmental and resource costs and benefits associated with implementing these improvements. The recent literature focuses almost exclusively on the assessment of the economic values related to quality aspects. However, in much of southern Europe, fulfilling the WFD goals will greatly depend on maintaining sufficient water flow, as well. This study aims to fill this gap by assessing the non-market value of allocating enough water to the environment to ensure environmental services are sustained when water is scarce. The non-market value of guaranteeing water supply for secondary household uses is also estimated. Using the Guadalquivir River Basin in Spain as a case study, a choice experiment is applied with scenarios characterized by varying water flow levels and accompanying environmental impacts, and a different frequency of household water restrictions. The results show that the population derives significant benefits not only from the direct use of water, but that also holds non-use values related to the ecological status, although the latter has a considerably lower impact on consumer surplus. Additionally, we conclude that the costs of implementing the water saving measures currently included in the Program of Measures seem to be proportionate to its benefits in this case.     

Viability of increasing the tariff of freshwater for irrigation as a tool to stimulate wastewater reuse in the MENA region.

Despite water scarcity and high agricultural water demand in the Middle East and North Africa region, substantial proportions of treated wastewater are discharged into the environment and seas without proper utilization. All countries of the region, low pricing of reclaimed wastewater is a common tool to make reuse attractive. However, low pricing of reclaimed wastewater is ineffectual due to farmers' access to freshwater for irrigation at low tariff. Therefore, increasing the prices of freshwater in such a way that does not jeopardize feasibility of agriculture would promote irrigation with reclaimed wastewater even at increased prices. On one hand, it increases the gap between the price of freshwater and that of reclaimed wastewater, making the later more attractive. On the other hand, it would be used as a financial resource for funding the investment costs of the infrastructure needed for conveyance and distribution of reclaimed wastewater. This paper studies the viability of increasing the prices of freshwater and reclaimed wastewater. The results show that irrigation with reclaimed wastewater even for restricted irrigation can be as profitable as, and sometimes better than, freshwater irrigation. Some of the permitted crops such as fruit trees can be more profitable than vegetables. Thus, it appears that the level of knowledge farmers and others on the benefits of reclaimed wastewater is still limited.     

北京市农业节水灌溉成效存在问题及发展对策

针对北京市农业节水灌溉、设施农业和再生水灌区发展现状以及节水灌溉存在的主要问题进行了分析,并以此分析为基础,提出今后一段时间内,农业节水灌溉发展对策,即构建农业灌溉高效节水体系和农业水资源科学管理体系。山区重点围绕特色林果、绿色养殖、生态旅游三大主导产业发展节水;平原近郊区围绕都市型现代农业以井灌区节水改造和建设再生水灌区为重点,调整用水及农业种植结构,提高灌溉水利用效率。     

Quantitative Analysis of Eco-economic Benefits of Urban Reclaimed Water Greening Based on Emergy Theory

With an increased rate of urbanization and people’s interest in high-quality natural environments, urban green spaces are receiving increased attention. However, urban green spaces irrigation increases tap water consumption, wasting high-quality water. Using reclaimed water for irrigation can not only maintain the normal ecological and landscape functions of green spaces but also save water resources. The eco-economic benefits of using reclaimed water as irrigation water were evaluated in this paper. The composition of benefits was analysed, and a new quantitative method was proposed based on the emergy theory. This proposed method was used to calculate the costs of different irrigation water, the other use benefits of the saved tap water, and the benefits of scientific research, leisure and entertainment, carbon fixation and oxygen release, biodiversity protection, soil conservation and air purification. Taking Zhengzhou in 2018 as an example, the results showed that the cost of using reclaimed water to irrigate urban green spaces was 46% of the cost of using tap water. The total benefit of using reclaimed water to irrigate green spaces was $4.05 billion, which was three times the benefit of using tap water. The net benefit of using reclaimed water was $2.00 billion, while that of tap water was negative. Therefore, the advantages of using reclaimed water to irrigate urban green spaces are the low costs and high eco-economic benefits. The method proposed in this paper provides a quantitative basis for using reclaimed water to irrigate urban green spaces in cities with water shortages.

     

Impacts of Combined Technical and Economic Measures on Water Saving in Agriculture under Water Availability Uncertainty

In Emilia Romagna region (northern Italy), the Water Protection Plan (WPP) — a tool designed to reach the objectives of the Water Framework Directive — established different measures to achieve a good quantitative status of water bodies. The objective of this study is to evaluate the combined economic, agronomic and environmental impacts of four measures of the WPP on the “Renana” reclamation and irrigation scheme, and to quantify the water conservation in agriculture under the uncertainty of water availability. To this purpose, a mathematical stochastic model able to represent uncertainty in water availability was designed and implemented. Some data were collected from farms, and local sources were used as well to test the model. Each analyzed measure was simulated in a single scenario, and subsequently combined with other measures. The performed simulations are the following: application of volumetric water pricing (Scenario WFD1), awarding incentives for farmers to improve on-farm irrigation efficiency (Scenario WFD2a), combination of WFD1 and WFD2a (Scenario WFD2b), reduction of water abstraction in case of water shortage (Scenario WFD3a), combination of WFD1 and WFD3a (Scenario WFD3b), increasing distribution efficiency in the channel system (Scenario WFD4a) and combination of WFD1 and WFD4a (Scenario WFD4b). Results have shown that scenarios WFD2a and WFD4a generate a higher income for farmers and produce a positive ecological impact (water use and soil cover) but tend to increase total water use. Scenarios WFD1 and WFD3a have the opposite effects since they reduce farmers’ income but decrease water use as well. Only WFD1 could be favorable for the Board governing the scheme (RIB) in terms of economic returns. Finally, results have shown that combined scenarios WFD2b and WFD4b, respectively, could modify the trade-off between economic and environmental objectives and could be more effective since they significantly reduce water consumption and minimize losses in farmers’ income.     

再生水灌溉利用对作物—土壤系统影响

再生水灌溉是解决农业缺水问题的有效方法,已经在诸多国家和地区得到广泛发展。我国缺水问题严重,而农业灌溉用水是主要的耗水方式之一,发展再生水为农业灌溉用水将是可持续发展的一个重要途径。现针对当前再生水回用的现状进行了分析,阐述了再生水灌溉对农作物以及土壤系统产生的影响,探索合理的再生水灌溉方式来缓解再生水对农作物及土壤环境带来的影响,并探讨再生水作为灌溉用水所需要达到的水质标准。基于对再生水的一系列研究,讨论了再生水灌溉对农作物-土壤系统的影响研究中的不足,为未来再生水灌溉研究提供理论基础。     

再生水农业利用现状及其研究进展

水资源严重短缺已经成为制约我国经济社会可持续发展的瓶颈,而且受生态环境用水不断加强的影响,农业用水变的愈加紧张,再生水的农业利用是缓解这种紧张局势的重要举措之一.现详细总结了国内外再生水的农业利用现状,从再生水灌溉水质标准、再生水灌溉对作物生长、土壤及作物生长环境的影响、再生水灌溉技术及灌溉制度等几个方面论述了其研究进展;最后对再生水灌溉存在的问题及今后的重要研究方向进行了分析.     

Water Costs Allocation in Complex Systems Using a Cooperative Game Theory Approach

The management of complex water resource systems that address water service recovery costs and consider adequate contributions and priorities require methods that integrate technical, economic, environmental, social and legal aspects into a comprehensive framework. In Europe, the Water Framework Directive (WFD) 2000/60/EC recommends that the pricing politics in a river basin take into account the cost recovery and the economic sustainability of the water use. However, the current cost allocation methods do not consider the user’s willingness to pay and often do not permit a total cost recovery. Thus, a new approach is required that includes these requirements when defining water rates. This article presents a methodology to allocate water service costs in a water resource system among different users that attempts to fulfil the WFD requirements. The methodology is based on Cooperative Game Theory (CGT) techniques and on the definition of the related characteristic function using a mathematical optimisation approach. The CGT provides the instruments that are necessary to analyse situations that require a cost-sharing rule. The CGT approach can define efficient and fair solutions that provide the appropriate incentives among the parties involved. Therefore, the water system cost allocation has been valued as a game in which it is necessary to determine the right payoff for each player that is, in this case, a water user. To apply the CGT principles in a water resources system, the characteristic function needs to be defined and evaluated using an adequate modelling approach; in this study, it is evaluated using the optimisation model WARGI. (Sechi and Zuddas 2000). The so-called “core” represents the game-solution set. It represents the area of the admissible cost allocation values from which the boundaries on the cost values for each player can be supplied. Within the core lie all of the allocations that satisfy the principles of equity, fairness, justice, efficiency and that guarantee cost recovery. The core of a cooperative game can represent a useful instrument to define the water cost rates. Furthermore, it can be used as a valid support in water resource management to achieve the economic analysis required by the WFD. The methodology was applied to a multi-reservoir and multi-demand water system in Sardinia, Italy.     

锦州市实用灌溉新模式效益研究

锦州市作为辽宁省粮食主产区,常年受到旱灾影响,为解决春旱秋吊问题,锦州市在国家与辽宁省政府的支持下推行节水灌溉工程,收效显著。但同时也存着不能适时补充灌溉、部分地区电力设施不足制约设备使用等问题。针对这些问题,本文提出了"风力提水+蓄水池模式+吸力式微润灌水器"的灌溉模式,以锦州市黑山与凌海两个项目区作为试点开展推广。实践证明,该灌溉模式可以很好地解决项目区存在的问题,经济收益、节水效果显著,还可以调动农户的积极性,促进农业良性循环。     

The water reclamation and reuse project of El Prat de Llobregat, Barcelona, Spain.

Water reclamation and reuse have become essential components of water resources management in the Metropolitan Area of Barcelona, by helping to develop additional water resources in the lower Llobregat River, one of its main sources of water supply. By generating a reliable flow of 300,000 m3/day of high quality reclaimed water, the options available for integrated water resources management have widely expanded to allow in-stream river water substitution, restoration of natural wetland areas, agricultural irrigation, and supply to a seawater intrusion barrier. Those management options have been possible thanks to the implementation of an extensive water distribution system that allows distribution of reclaimed water to a point 15 km upstream of the reclamation facility, and to a seawater intrusion barrier within a few kilometres of the plant. The cost of producing reclaimed water using a physico-chemical process (0.05 euro/m3) and the investment required for such a facility (0.21 euro/m3 annual capacity) are very close to those of similar large scale projects in Spain. However, higher degrees of treatment, such as demineralization for agricultural irrigation and for injection into a seawater intrusion barrier, result in considerable increases of both water reclamation cost and investment costs.     

On the Scarcity Value of Irrigation Water: Juxtaposing Two Market Estimating Approaches

The aim of this paper is to compare the supply-side and demand-side approaches for assessing the scarcity rents of irrigation water. The results obtained from the case study confirm the expectation that the demand-side rationale provides the lower bound estimate of water scarcity rents. Specifically, a hypothetical elimination of water scarcity brings extra benefits to the local farmers, but these benefits cannot compensate the costs of the backstop technology which provide such extra water. Therefore, the lost opportunities, in terms of income forgone due to water scarcity, cannot legitimize supply-side approaches alone. A “soft” sensitivity analysis was included to examine the robustness of such a cost-effective property, while the policy implications of the results are also examined.     

综合利用水利枢纽投资分摊方法研究

在对综合利用水利枢纽进行投资划分的基础上，对常用的５ 种投资分摊方法，即枢纽指标系数分摊法、效益比例分摊法、替代措施费用比例分摊法、可分离费用 剩余效益分摊法和主次分摊法，进行了系统的评述；建议对效益比例分摊法和替代措施费用比例分摊法加以改进，统一并入可分离费用 剩余效益法，统称为综合的可分离费用 剩余效益法；推荐使用综合的可分离费用 剩余效益法和枢纽指标系数法，并指出投资分摊时应注意的有关问题．     

再生水灌溉研究进展

从再生水灌溉对土壤、作物、地下水和土壤斥水性4个方面简述国内外再生水灌溉的发展概况和研究进展。已有研究表明：再生水灌溉对土壤肥力和土壤酶活性的影响尚未有定论;再生水对农作物生长的影响尚有分歧;再生水灌溉对地下水水质具有一定的影响,并显著影响地下水水环境;长期的再生水灌溉会引发土壤斥水性的产生,且土壤斥水持续时间与土壤有机质质量分数呈正相关。目前存在的问题有：再生水灌溉对土壤和农作物的影响研究不一致,如何消除再生水灌水对地下水和土壤斥水性的影响。认为由于再生水中含有作物正常生长的必要营养元素,若能克服再生水灌溉存在的问题,可缓解淡水资源的压力和减少化肥的使用,避免环境的污染。     

Ecological Engineering in Water Resources

Abstract

Ecological engineering is a relatively unfamiliar; cost-effective strategy for tackling the “second generation” of water resource problems. It can be defined as the design, construction, operation, and management of landscape/aquatic structures and associated plant and animal communities to benefit humanity and nature. It is introduced by comparing it with “conventional” engineering, including case studies with cost and performance data. Ecological engineering can offer important potential advantages: better performance, less cost, multiple benefits, and better acceptance by the public and regulators. It can cost less because structures are sometimes not as highly engineered and are durable and self-maintaining. Natural energy sources and self-regulating processes reduce operation and maintenance costs. The ancillary benefits can be ecological, recreational, or economic. Case studies include a treatment of wetland to remove nitrogen from wastewater, a lakeshore stabilization project, and stream and riparian restoration via beaver reintroduction. The investigation concludes with a discussion of obstacles and caveats for ecological engineering.     

Assessment of Environmental Water Cost Through Physical Hydronomics

The Georgescu-Roegen’s statements about the connexion between the Economy and the Thermodynamics, together with the Eco-integrator approach introduced by Naredo and its relation with the water cost definitions given in the European Water Framework Directive (WFD), are the outline backgrounds of the work presented in this paper. Assuming that the physical laws are called to be the objective and universal tools to assess water costs, Physical Hydronomics (PH) has been developed as the accounting tool for the WFD application, regarding its physico-chemical objectives. PH is defined as the specific application of the Thermoeconomics to physically characterize the degradation and correction of water bodies. The Second Law of Thermodynamics, through the exergy loss calculation, is the basic working tool in this study. The final objective of PH is to use those calculated physical costs of water as a guide to allocate the environmental and resource costs introduced by the WFD. In this paper, the general framework and the basic accounting principles of PH are explained. First, from the quantity and quality measurements in the river (they give the exergy value to water bodies), the exergy profiles of the river at different statuses (those defined by the WFD) are obtained. Then, the environmental cost of water is obtained (in energy units) as the exergy needed to cover the gap between the current state of the river and the objective state defined by the applicable legislation to fulfil the European requirements. To do it, thermodynamic efficiency of water treatment technologies was introduced in the analysis. Then, the physical cost are translated into monetary units. To illustrate the application of the PH’s methodology, the example of the Spanish Muga Basin, sited in the Inland Basins of Catalonia, is summarized at the end of this paper. The results show that similar results to conventional Measurements Plans to fulfil the WFD objectives are obtained. However, PH presents an important advantage: costs could be allocated according to the degradation (exergy costs) provoked by the different water users in the water bodies.     

Coping with Urban & Agriculture Water Demand Uncertainty in Water Management Plan Design: the Interest of Participatory Scenario Analysis

Managing water scarcity is a major challenge for regions all over the world. In the European Union, robust methodologies are needed to establish effective programmes of measures aimed at achieving the “good status” of water bodies according to the Water Framework Directive (WFD). These programmes often target the current gap between the actual status of water bodies and the “good” status without accounting for uncertainty in water demand. We develop a new methodological framework that enable to account for uncertainty in future water demand and design programmes in order to increase their likelihood of attaining the good quantitative status. The foresight approach enables to construct and quantify future water demand scenarios hand-in-hand with stakeholders during workshops. They consist in identifying drivers, debating pre-constructed scenarios, reconstructing scenarios and estimating water demand. The impact of the co-constructed scenarios is simulated with a resource-demand balance model for all water resources and a cost-effectiveness analysis makes it possible to construct programmes that target the estimated future water deficits at least cost. The methodology is illustrated with an application to Reunion Island (Indian Ocean, France) considering agriculture (Ag) and urban water (Uw) demand. Three combinations of sector scenarios (Uw, Ag) were produced and coherence was eventually ensured by fitting the land use parameter. This solution can accommodate case studies faced with a binding land constraint for housing and agriculture. As each scenario implies significantly different programmes of measure in terms of intensity and spatial distribution, results demonstrate the importance of taking uncertainty on water demand into account.     

Domestic Use of Irrigation Water: Health Hazard or Opportunity?

In an environment of growing scarcity and competition for water, there is increasing pressure on the irrigation sector to make irrigation for crop production more efficient and to transfer water to the urban, industrial and environmental sectors. However, irrigation water is extensively used for non-agricultural purposes, including domestic purposes, and an exclusive focus on water efficiency in agriculture could actually reduce the availability of domestic water within irrigated areas. It is argued, based on available literature, that this would have important health implications because in many developing countries the availability of water, rather than the quality of water, is of crucial importance to health. Two case studies are presented from Sri Lanka and Pakistan where people make use of irrigation water for a range of domestic activities. Water resource policies have to take these uses into account to avoid negative health implications for poor disadvantaged segments of the population. Barriers to optimizing benefits of linking the irrigation water supply to domestic needs seem to be institutional and psychological rather than medical, technical or economic.     

Cost Analysis of Water Quality Assessment Using Multi-Criteria Decision-Making Approach

In modern competitive markets, cost and quality parameters are the two main factors. So, it is essential to study their relationship, especially in leading industries such as urban public service companies. Consequently, manufacturers always try to reduce production costs and improve product quality and services to consumer expectations. Also, the concerns of the new century in the field of fresh water and the reduction of its resources related to global warming have increased the costs of quality and supply of freshwater. Therefore, in this research, in order to estimate the quality costs in the field of water resources and wastewater management and identify the option that creates the most cost, in the first step, the “Prevention, Assessment, and Failure (PAF)” model was used to select cost-imposing options in organizational quality analysis. After determining the main options, appropriate criteria and sub-criteria were selected under the main study area (water and wastewater resources management). In the next step, a “Multiple-Criteria Decision-Making (MCDM) “ method based on the “Fuzzy Analytical Hierarchy Process (FAHP)” and “Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS)” method was used to identify the option that creates the most cost. The results show that The highest cost of quality in the water and wastewater industry and its management are related to “Assessment Costs” and account for 36.55% of total costs. Also, The lowest cost of quality in the water and wastewater industry is related to “Preventive Costs” and accounts for only 12.18% of the total cost. In addition, the expert’s opinion shows that the effect of increasing credit with 34.01% has the greatest weight, and this criterion is the most essential in water and wastewater resources management.

     

Reusing Urban Wastewater—An Alternative and a Reliable Water Resource

ABSTRACT

Fundamental concepts of reusing urban wastewater as an alternative and a reliable source of water supply are discussed, along with the categories for water reuse, planning methodologies, wastewater reclamation technologies, and economics. The rational basis for integration of urban reclaimed water into water resources planning is proposed and the safe use of reclaimed water is evaluated. Special attention is paid to tertiary or advanced wastewater treatment systems that are capable of producing essentially pathogen-free effluent for a variety of uses such as irrigation of urban landscape, flushing of toilets served by dual plumbing systems in large commercial buildings, and groundwater recharge for eventual potable reuse. The motivating factors for wastewater reclamation and reuse are summarized and the costs of water reclamation projects are discussed with several examples. The integration of this alternative water supply into water resources planning is proposed and the safe use of reclaimed water is emphasized.     

考虑水质与水价影响的城市再生水需求研究

再生水是城市的“第二水源”,加强再生水配置利用对优化供水结构、增加水资源供给、缓解水量供需矛盾以及保障水生态安全具有重要意义。科学预测城市再生水需求是提高污水资源化利用水平的重要基础。在区域水资源需求分析基础上,充分考虑工业生产、城市杂用、河道补水、农林灌溉等4大领域的水量和水质需求特点,提出考虑水质与水价的分领域再生水需求预测技术框架。首先考虑水质影响,引入再生水可替代率指标,分析水资源需求总量中可由再生水供给的水量;其次,考虑自主定价模式下再生水价格对用户需求的影响,建立“补贴-价格-需求”模型,计算不同补贴情景下区域再生水的需求量;最后,应用于宿迁市中心城市。结果表明：在规划年2025和2030年的再生水利用率目标要求下,采用中等补贴情景能在有效推广再生水利用的同时兼顾政府财政压力,再生水需求量分别可达10 095×10⁴和13 387×10⁴ m³。本研究进一步拓展了城市再生水需求量预测的理论方法,也为宿迁市再生水利用配置提供了科学依据。