Suitability of Water Quality Indices for Application in Lakes in the Mediterranean

Water quality indices (WQIs) are efficient and powerful tools for evaluating, organising and communicating information on the overall quality of surface water bodies. The use of these indices may be very helpful in evaluating the water quality of aquatic systems in relation to the EU Water Framework Directive (WFD). In this study, two well-known water quality indices have been selected for evaluation: the CCME (Canadian Council of Ministers of the Environment) and NSF (National Sanitation Foundation). These WQIs were applied in the Polyphytos reservoir-Aliakmon river in Greece where monthly water quality data were available for the period June 2004 to May 2005. The available dataset included values of the following parameters: water depth, water temperature, dissolved oxygen, electrical conductivity, pH, transparency (Secchi disk depth), BOD₅, COD, total phosphorus (TP), chlorophyll-a (Chl-a), ammonium (NH₄ ⁺), nitrite (NO₂ ^?) and nitrate (NO₃ ^?), and total Κjeldahl nitrogen (TKN). The application of the two WQIs was made using specialised, freely available software-tools. A comparison of their performance and a qualitative judgement on their suitability on expressing the quality of a surface water body is presented. The classification results were compared with those obtained by the WFD-ECOFRAME approach of the EU. Based on the applicability and drawbacks of the examined indices, useful conclusions were derived and discussed. Among others, it is concluded that the NSF-WQI is a more robust index and produces a classification nearer that of the WFD-ECOFRAME approach when compared to the CCME-WQI.     

Dynamic weighting system for water quality index

Water quality standards are developed world over by National and International agencies for pollution control decision-making. Use-based water quality classification criteria and Water Quality Indices (WQIs) also play important role in assessment of water resources for their suitability with reference various uses. Formulation of value function curves and weights assigned to parameters in WQIs are often defined by local water experts and hence WQIs are known to inherit subjectivity. Assignment of weights a priori to various water quality parameters results in misclassification of water quality by WQI. A method of dynamic weighting has been developed in the present work to assign weights to water quality parameters with due consideration to their pollution effect at a particular site. Application of a methodology to Overall Index of Pollution (OIP) provides water quality classification of Indian rivers as "Polluted", "Acceptable", and "Slightly Polluted", which is comparable with the reported CPCB classification as well as with the statistical index CCME-WQI. The methodology developed is general and can be applied to any subjective index. This is exemplified by dynamically weighting the parameters in NSF-WQI for Red and Waikato rivers. Dynamic weighting system provides a true representation to comprehend water quality classification and to achieve River Quality Objectives.     

One View of the Future

Abstract

Floods, droughts, water scarcity, and water contamination are some among many water problems that are present today and will be even more noticeable in the future. In the past, many different tools have been used for simulation and optimization of complex water resources systems in order to provide an improved basis for decision making. The continuing evolution of information technology (hardware and software) creates a good environment for the transition to new tools. Application of the systems approach to water resources planning, management, and operations has been established as one of the most important advances made in the field of water resources engineering. Based on the lessons learned, this contribution provides my personal view on the tools to be used in the future. Two paradigm shifts are discussed. The first one is focusing on the complexity of the water resources domain and the complexity of the modelling tools in an environment characterised by continuous rapid technological development. The second one deals with water-related data availability and natural variability of domain variables in time and space affecting the uncertainty of water resources decision making.     

Synthesis of System Dynamics Tools for Holistic Conceptualization of Water Resources Problems

Out-of-context analysis of water resources systems can result in unsustainable management strategies. To address this problem, systems thinking seeks to understand interactions among the subsystems driving a system??s overall behavior. System dynamics, a method for operationalizing systems thinking, facilitates holistic understanding of water resources systems, and strategic decision making. The approach also facilitates participatory modeling, and analysis of the system??s behavioral trends, essential to sustainable management. The field of water resources has not utilized the full capacity of system dynamics in the thinking phase of integrated water resources studies. We advocate that the thinking phase of modeling applications is critically important, and that system dynamics offers unique qualitative tools that improve understanding of complex problems. Thus, this paper describes the utility of system dynamics for holistic water resources planning and management by illustrating the fundamentals of the approach. Using tangible examples, we provide an overview of Causal Loop and Stock and Flow Diagrams, reference modes of dynamic behavior, and system archetypes to demonstrate the use of these qualitative tools for holistic conceptualization of water resources problems. Finally, we present a summary of the potential benefits as well as caveats of qualitative system dynamics for water resources decision making.     

Analysis of parameter variations in L-Q equations for river runoff processes from the viewpoint of spatial and temporal conditions.

This study aims to find out variation characteristics of the parameters of 'a' and 'b' in L = a x Q(b), an empirical equation for run-off loading (L) and flow rate (Q), by evaluating the effects of flow conditions and regional properties of the watersheds on the values. We selected the Kamo River basin (155 km2) as a study field, and conducted various kinds of investigations, such as 80 day high frequency observations, continuous monitoring for more than 2 years, storm event surveys, and simultaneous surveys of 39 stations. Then, we obtained 7-170 data in each of 39 sampling stations. The main results obtained are as follows: (1) L-Q equation with a range of 'a' can express L-Q relation in most of the WQIs (water quality indices); (2) 'a' receives temporal (flow condition) effects more in SS, VSS and Al, while it receives regional effect more in inorganic carbon, TN, Ca and Fe; (3) both of flow change in storm events, and base flow levels affect the L-Q relation, and their effects can classify the WQIs into several groups; (4) the effects of regional properties were obviously observed in 'a', and quantitatively evaluated, especially for density of population.     

Evolution of a new surface water quality index for Karoon catchment in Iran

Water quality standards are developed worldwide by national and international agencies for pollution control decision-making. Use-based water quality classification criteria and Water Quality Indices (WQIs) also play an important role in the assessment of the suitability of water resources for various applications. The present study proposes a better overall index for water quality in Iran and its application in Karoon River by exploring the behavior and limitations of conventional methods for quality evaluation. For this purpose, six variables were employed. Water quality determinants of the new index include Dissolved Oxygen, Total Dissolved Solids, Turbidity, Nitrate, Fecal coliform and pH. Besides, the mathematical equations applied to transform the actual concentration values into quality indices have been formulated. This study compares a new index called the Iranian Water Quality Index with other pre-existing indices such as NSFWQI, Oregon, CPCB WQI, MDOE WQI, Kaurish and Younos WQI, and Ahmed Said WQI. Results revealed that the overall quality of the surface water falls under the 'good' class. A case study of Karoon River is made to illustrate the application of this new index system.     

Applicability of Adapted Reservoir Operation for Water Stress Mitigation Under Dry Year Conditions

This paper introduces the conjunctive use of a deterministic water quality model and water balance criteria for supporting the assessment of simulation and to evaluate the effectiveness of proposed operation strategies. By this, the applicability of enhanced reservoir operation strategies addressing both water quality as well as water quantity aspects under water deficit conditions in dry years can be shown. Arguments will be developed to address stakeholders and decision makers in the context of a more conservative past operation regime. Results are presented for the Kaparas reservoir, which is located in the lower Amu Darya River, on the border of Turkmenistan and Uzbekistan. As being one out of four large reservoirs of the Tuyamuyun Hydro Complex (THC), the Kaparas reservoir could be increasingly used for drinking water supply for the lower Amu Darya region. The results for the dry year 2001 indicates that the combination of simulation together with practical assessment criteria confirm the applicability of adapted operation rules for THC reservoirs and ways can be found to supply the local population (of the lower Amu Darya region) with more potable water of higher quality even subject to a parallel reduction of water deficits. Future aggravation of water stress due to increasing population growth and water quality deterioration will require a more comprehensive consideration of water quality aspects in many arid and semi arid regions. The experience gained during this study emphasizes the fact that classical deterministic water quality models provide effective tools to address even more complex water quality problems under water stressed conditions, provided processing of results is performed, to support the decision making process.     

Benthic Response to Flow Alteration in a New Mexico Arid Mountain Stream

Past and current pressure on streams and rivers for consumptive use requires the development of tools and decision‐making processes for water managers to minimize impacts on ecological function. This paper examines the utility of modeling benthic biomass in relation to benthic macroinvertebrate (BMI) community attributes for water resource management scenarios in the Cliff‐Gila Valley of the Gila River, New Mexico, USA. The river benthos biomass model (RivBio) was used in conjunction with hydraulic modeling to predict growth and decline of benthic biomass. BMI community attributes were compared along gradients of hydrologic impact (successive existing diversions) in the Cliff Gila Valley and were compared to community attributes in similar regional streams. Benthic biomass was minimally affected by proposed diversions at flows above 4.25 cms (150 cfs), but was severely reduced downstream because of existing diversions during lower flow periods. Riffle habitat was disproportionately affected during extreme low and interrupted flow, which may have resulted in BMI communities shifted towards multi‐habitat generalists that can persist in lentic conditions. Flow augmentation from proposed diversions and storage would greatly mitigate these existing biomass losses by providing consistent base flow and lotic conditions in riffle habitat. Both benthic biomass and BMI community endpoints were useful when comparing water management scenarios. Copyright © 2016 John Wiley & Sons, Ltd.     

Multiobjective Calibration of Reservoir Water Quality Modeling Using Multiobjective Particle Swarm Optimization (MOPSO)

Water resource management encounters large variety of multi objective problems that require powerful optimization tools in order to fully characterize the existing tradeoffs between various objectives that can be minimizing difference between forecasted physical, chemical, and biological behaviors of model and measured data. Calibration of complex water quality models for river and reservoir systems may include conflicting objectives addressed by various combinations of interacting calibration parameters. Calibration of the two dimensional CE-QUAL-W2 water quality and hydrodynamic model is an excellent example where the model must be calibrated for both hydrodynamic and water quality behavior. The aim of the present study is to show how multiobjective particle swarm optimization (MOPSO) can be implemented for automatic calibration of water quality and hydrodynamic parameters of a 2-dimensional, hydrodynamic, and water quality models (CEQUAL-W2) to predict physical, chemical, and biological behaviors of a water body, and then focus on a relevant case study. So MOPSO is utilized to generate Pareto optimal solutions for two conflicting calibration objectives. A combined measure of thermal and reservoir water level is considered as the first calibration objective. The second objective is formulated to forecast the best physical, chemical, and biological behavior of the model. Realizing the strong interactions between water quality and hydrodynamic issues of water bodies and their dependencies on the same set of calibration parameters, the proposed multiobjective approach may provide a wide version of all possible calibration solutions for better decision making to select best solution from pareto front.     

Basin Scale Water Resources Systems Modeling Under Cascading Uncertainties

Global change in climate and consequent large impacts on regional hydrologic systems have, in recent years, motivated significant research efforts in water resources modeling under climate change. In an integrated future hydrologic scenario, it is likely that water availability and demands will change significantly due to modifications in hydro-climatic variables such as rainfall, reservoir inflows, temperature, net radiation, wind speed and humidity. An integrated regional water resources management model should capture the likely impacts of climate change on water demands and water availability along with uncertainties associated with climate change impacts and with management goals and objectives under non-stationary conditions. Uncertainties in an integrated regional water resources management model, accumulating from various stages of decision making include climate model and scenario uncertainty in the hydro-climatic impact assessment, uncertainty due to conflicting interests of the water users and uncertainty due to inherent variability of the reservoir inflows. This paper presents an integrated regional water resources management modeling approach considering uncertainties at various stages of decision making by an integration of a hydro-climatic variable projection model, a water demand quantification model, a water quantity management model and a water quality control model. Modeling tools of canonical correlation analysis, stochastic dynamic programming and fuzzy optimization are used in an integrated framework, in the approach presented here. The proposed modeling approach is demonstrated with the case study of the Bhadra Reservoir system in Karnataka, India.     

A Landscape Planning and Management Tool for Land and Water Resources Management: An Example Application in Northern Ethiopia

Land and water degradation due to on-site soil/nutrient loss and off-site pollution/sedimentation are serious environmental problems. Landscape planning and management tools are essential to implement best management practices targeted at locations where they are needed most. Although many soil/water-landscape studies have been published in the last 2 decades, progress in developing operational tools for supporting landscape planning to minimize land and water degradation in developing regions is still modest. Some of the existing tools are data demanding and/or complicated to be useful to data scarce regions. Some require detailed understanding of the hydrological and modelling processes and thus less applicable to local stakeholders involved in land use planning and management. A user-friendly LAndscape Planning and MAnagement Tool (LAPMAT) developed to facilitate land management decision-making. LAPMAT is a menu-oriented interactive graphical user interface that can aid decision makers identify hotspot areas of soil erosion and evaluate the effects of alternative land use management practices at a catchment scale. The modelling framework and its interfaces are designed to guide the user through a series of menus that: 1) allow input model parameters, adjusting coefficients, visualizing input parameters and executing the model; 2) enable changing land use and management practices and re-evaluating potential consequences; 3) allow viewing results in tabular, graphical or map form side-by-side; and 4) (re)-evaluating the respective impacts of management/conservation options. The framework has been applied to assess the severity of soil erosion and simulate the impact of different land management practices using the Revised Universal Soil Loss Equation (RUSLE) adjusted for sediment delivery ratio in an example catchment of northern Ethiopia. The results showed average sediment yield rate of 55 t ha^?1 y^?1. Conservation measures targeted at high soil loss areas and gullies gave the maximum reduction in sediment yield by about 80 %. Since LAPMAT allows users handle the selection of management/planning options and provide fast and responsive outputs, it can assist in effective multi-stakeholder negotiations over land-use planning where the minimization of land/water degradation is the ultimate goal.     

El Niño–Southern Oscillation Link to South Florida Hydrology and Water Management Applications

This study evaluates the relationships between El Niño–Southern Oscillation (ENSO) indices and South Florida hydrology and proposes applications to water management decision making. ENSO relations to the Upper Kissimmee Basin rainfall, watershed for Lake Okeechobee, and cumulative sea surface temperature (SST) anomalies at Niño 3.4 were evaluated. Additionally, relationship between ENSO and Lake Okeechobee inflows, Arbuckle Creek and Josephine Creek flows were analyzed. Hydrology of the northern watersheds of the South Florida water management system is linked to ENSO events. Dry season (November–May) rainfall and flows are higher than average during El Niño years and lower during La Niña years, at the 90% confidence level or higher. The relationship is strongest when the ENSO event is strong as shown with analysis of correlation. ENSO prediction has more certainty than hydrologic prediction for a region. Identifying ENSO and hydrologic relationships can aid water management decision making by providing a lead-time of months to mitigate drought or flood impacts. The ENSO tracking method, which was published in a previous study, is presented to track ENSO strength and event type to provide supplemental outlook on dry season rainfall for Lake Okeechobee operations. Lake Okeechobee, which is the main storage in the South Florida water management system, is regulated by a schedule with a limited band of stage fluctuation because of susceptibility of the Herbert Hoover Dike to wave erosion and seepage at high stages. An early decision making approach to storage management with respect to ENSO related hydrology, is presented based on tracking the strength of ENSO events.     

我国现有水资源冲突管理制度体系探析

对我国现行的水资源冲突管理制度体系展开了述评。主要梳理了国家制定的水资源冲突管理制度、国务院组成部门的水资源冲突管理制度,以及上述两类制度的主要内容;分析了水量冲突管理制度、水质冲突管理制度以及跨界水资源冲突管理制度存在的不足之处。在此基础上,提出了完善我国水量冲突管理制度、水质冲突管理制度、跨界水资源冲突管理制度方面的有益建议,可为水资源冲突管理部门和相关决策机构系统构建我国的水资源冲突管理制度提供参考与借鉴。     

A new approach to aid urban water management decision making using trade-off sacrifice modelled by fuzzy logic.

An approach to aid decision making for urban water management is presented that is based on the concept of trade-off sacrifice level in pairwise comparisons between criteria, modelled using fuzzy logic. This approach is illustrated by a case study - selection of alternative water supplies for a Sydney household. Four key decision making criteria covering health, economic, environment and technical aspects are selected: annual probability of infection, life cycle energy use, life cycle cost and reliability. The decision making problem is to select between cases with different volume and application of recycled greywater and rainwater in light of the four criteria. Decision maker's preference is expressed by five levels of trade-off sacrifice between pairs of criteria. The decision makers can assign their preferences for sacrifice level by linguistic assessment and the output trade-off weight (TOW). Measures of decision makers' perceived trade-off level are modelled by a rule-based fuzzy logic control system. The final analysis shows the performance for each sacrifice class for each case, to aid overall decision making with stakeholders.     

Vulnerability to Drought of a Complex Water Supply System. The Upper Tiber Basin Case Study (Central Italy)

The importance of simulation models to assess the impacts of droughts and the effects of mitigation options on water supply systems is well known. However a common procedure about the exploitation of model results is not established yet. Vulnerability is used to characterize the performance of the system, and it can be a helpful indicator in the evaluation of the most likely failures. In this paper a water allocation model is applied to the water supply system of the upper Tiber Basin (Central Italy) in which both surface waters (rivers, reservoirs) and ground waters (wells, springs) are exploited to feed mainly irrigation and civil users. Drought vulnerability indices are calculated to analyze the performance of the supply system under different climate and management conditions. Water shortage scenarios are simulated as a progressive reduction of mean precipitation, an increase in its standard deviation or a combination of both. The model shows that the safety of the water supply system mainly relies on the reservoirs and that the foreseen increased exploitation of the springs to replace contaminated wells, could be seriously limited by discharge decrease during fall. The vulnerability reduction obtained by a hypothetical augmentation of the storage capacity through additional small reservoirs was positively tested by the model. In conclusion vulnerability indices and synoptic risk maps demonstrated to be useful tools to analyze the model outputs. They provide easy-to-read scenarios to be used in a decision making framework considering negotiating among the main users.     

无锡水源地贡湖引水改善水质效果分析

为了分析“引江济太工程”对无锡市主要饮水水源地贡湖南泉水质的影响,建立了太湖二维水量水质模拟模型。在设定引水水质与水源地水质的条件下,针对常规和突发污染事故调度情况,模拟分析了引水枢纽望亭立交及梅梁湖泵站不同引水流量对南泉水源地水质的影响,掌握了水源地水质的恢复时间及恢复过程与引水流量的关系。研究结果可为水资源管理部门决策、优化工程调度、水源地供水安全保障提供科技支撑。     

我国高耗水工业用水效率评价

高耗水工业用水量占工业用水总量的3/4,是用水管理、节约用水的重点。文中按耗水量指标划分八大高耗水工业,选择万元增加值取水量与单位产品取水量两类指标,评价我国高耗水工业用水效率,揭示了高耗水工业用水存在的问题与成因,提出高耗水工业用水管理的政策建议,为高耗水工业的用水管理提供分析和决策依据。     

Operationalising uncertainty in data and models for integrated water resources management.

Key sources of uncertainty of importance for water resources management are (1) uncertainty in data; (2) uncertainty related to hydrological models (parameter values, model technique, model structure); and (3) uncertainty related to the context and the framing of the decision-making process. The European funded project 'Harmonised techniques and representative river basin data for assessment and use of uncertainty information in integrated water management (HarmoniRiB)' has resulted in a range of tools and methods to assess such uncertainties, focusing on items (1) and (2). The project also engaged in a number of discussions surrounding uncertainty and risk assessment in support of decision-making in water management. Based on the project's results and experiences, and on the subsequent discussions a number of conclusions can be drawn on the future needs for successful adoption of uncertainty analysis in decision support. These conclusions range from additional scientific research on specific uncertainties, dedicated guidelines for operational use to capacity building at all levels. The purpose of this paper is to elaborate on these conclusions and anchoring them in the broad objective of making uncertainty and risk assessment an essential and natural part in future decision-making processes.     

Participatory dam systems modelling: a case study of the transboundary Guadiana River in the Iberian Peninsula.

Modelling tools have been widely used to investigate best management practices. But in contrast to the plethora of modelling studies, the practical implementation of outcomes is comparatively small. There is an urgent need to implement results and to show the practical validation of the concept developed, especially against the context of water stress mitigation. The participative development of modelling studies as a joint effort of stakeholders and modellers is seen as a key to achieve a wider identification, acceptance, trust and applicability of results. Participatory planning in the water sector is also increasingly requested in water management, where tasks have been for clarified decades through different institutional arrangements and national laws. Stakeholder involvement in water resources management have been limited to what was long time seen as participation, merely information on action to be taken. In the last decade the need for participation has been reflected in different ways. In Europe, the implementation of the Water Framework Directive (WFD) under Art. 14, requires all the European countries to involve stakeholders in decision making processes on water resource management. The aim of this paper is to present and discuss the research framework and possible results of investigating dam modelling through participatory systems modelling. We introduce a structured approach to use participatory modelling (PM) for stimulating the integration of modelling and decision making, also as a way of implementation of some articles of the WFD. The results and the framing of this paper are part of the AQUASTRESS Project. The conceptual modelling has been developed by a multidisciplinary research team, local stakeholders and local experts. Some results are discussed and recommendations made.     

典型综合利用水库水环境问题及污染控制措施——以张峰水库为例

提出了“典型综合利用水库”的概念;论述了典型综合利用水库在水环境方面的主要特点;以张峰水库为例,研究了污染源、上游来流、库区及下游河段存在的主要水环境问题;结合2个已建水库-屯绛水库和后湾水库,论述了其水环境保护的经验;最后,对典型综合利用水库需采取的污染控制措施进行了探讨,并指出了落实保护中应注意的问题。本文的成果及观点对于典型综合利用水库的水环境保护管理及工程设计等方面将具有参考价值。