Selecting the Best Approach to Modeling the Performance of Water Supply System Using the Combination of Rough Set Theory with Multi-Criteria Decision Making

The purpose of this study is to select the best modeling approach (simulation or optimization) for operation the water supply system using multi-criteria decision-making method. For this purpose, the Geophysical Fluid Dynamics Laboratory-Earth System Models (GFDL-ESM2M) and the Model for Interdisciplinary Research on Climate-ESM (MIROC-ESM) models were selected to predict the changing trend of the climatic variables of rainfall and temperature, respectively. Then Artificial Neural Network (ANN) model and a decision support system tool named Cropwat were used to simulate water resources and consumption; and to model the behavior of the water supply system, the MODified SYMyld (MODSIM) (as simulator) and the modeling language and optimizer LINGO 18 (as optimizer) were used in the future time period (2026–2039) and the results were compared with the baseline period (1987–2000) for the Idoghmush reservoir (Iran). The results of MODSIM simulation model show that the indexes of reliability, vulnerability, reseiliency and flexibility in the future time period under the RCP2.6 emission scenario compared to the baseline time period decreased by 9%, decreased by 22%, increased by 4%, and decreased by 2%, respectively. The results of the LINGO 18 optimization model show that the reliability, vulnerability, resiliency and flexibility indexes in the future time period under the RCP2.6 emission scenario compared to the baseline time period decreased by 13%, decreased by 17%, increased by 14% and increased by 3%, respectively. Due to the different results obtained from optimization and simulation approaches for the study area, the Multi-Attributive Ideal-Real Comparative Analysis (MAIRCA) multi-criteria decision-making method was used to select a more appropriate approach. The results show that for water resources management planning, the simulation approach is given priority over the optimization approach due to its characteristics.

     

Multi-criteria Decision-making Approach for Environmental Impact Assessment to Reduce the Adverse Effects Of Dams

Water Resources Management - Environmental Impact Assessments (EIAs) of development projects are necessary to minimize negative impacts and maximize benefits. The objective of this paper is to...     

Assessment of Water Resources Development Projects under Conditions of Climate Change Using Efficiency Indexes (EIs)

The purpose of this study is to evaluate Gharanghu multi-purpose reservoir system (East Azerbaijan, Iran) using efficiency indexes (EIs) affected by climate change. At first, the effects of climate change on inflow to the reservoir, as well as changes in the demand volume over a time interval of 30 years (2040–2069) are reviewed. Simulation results show that inflow to the reservoir is decreased in climate change interval compared to the baseline interval (1971–2000), so that comparison of long-term average monthly inflow to the reservoir in climate change interval is reduced about 25% compared to the baseline. Also, water demand in climate change interval will increase, namely volume of water demand for agricultural, drinking and industrial, and environmental in climate change interval is expected to increase by 20%. The simulation results of the water evaluation and planning (WEAP) model is used to determine EIs of multi-purpose reservoir system. Next, three scenarios of water supply for climate change interval are introduced to WEAP model, keeping variable of parameter related to water demand volume (based on different percentages of supply) and keeping constant of the parameter related to the volume of inflow to the reservoir. Results show that system EIs in climate change interval will have a disadvantage compared to the baseline. So that, reliability, vulnerability, resiliency and flexibility indexes in climate change interval based on 100% of water supply compared to the baseline will decrease 18%, increase 150%, decrease 33%, and decrease 47%, respectively. These indexes based on 85% of supply compared to the baseline will decrease 12%, increase 75%, decrease 30%, and decrease 39%, respectively. Also, those based on 70% of supply compared to the baseline will decrease 1%, will be without change, decrease 18%, and decrease 18%, respectively. Changes in indexes in future interval indicate the need to manage water resource development projects in the basin.     

Prioritization of Water Allocation for Adaptation to Climate Change Using Multi-Criteria Decision Making (MCDM)

Water Resources Management - The complex nature of water resources and the related uncertainty cause decision making to be difficult in practice. In this study, two multi-criteria decision making...     

Evaluation of the VIKOR and FOWA Multi-Criteria Decision Making Methods for Climate-Change Adaptation of Agricultural Water Supply

Water Resources Management - Confronting climate change is a daunting challenge that requires policies for climate adaptation in the field of water resources management. This paper proposes a...     

Performance Indexes Analysis of the Reservoir-Hydropower Plant System Affected by Climate Change

Assessing the effects of climate change phenomenon on the natural resources, especially available water resources, considering the existing constraints and planning to reduce its adverse effects, requires continuous monitoring and quantification of the adverse effects, so that policymakers can analyze the performance of any system in different conditions clearly and explicitly. The most important objectives of the present research including: (1) calculating the sustainability index for each demand node based on the characteristics of its water supply individually and also calculating the sustainability index of the whole water supply system, (2) investigation the compatible of changes trend among various reservoir performance indexes and (3) evaluation the changes in performance reservoir indexes in the future time period compared to the baseline tie period under three Concentration Pathway (RCP) RCP2.6, RCP4.5 and RCP8.5 scenarios for all water demand nodes and the entire water supply system. To this end, first, climatic parameters data affecting on the water resources such as temperature and precipitation were gathered in the baseline period (1977–2001) and the climatic scenarios were generated for the future period (2016–2040) using the Fifth Assessment Report (AR5) of the International Panel on Climate Change (IPCC). Then, the irrigation demand changes of the agricultural products with the Cropwat model and the value of inflow to the reservoir with the Artificial Neural Network (ANN) model were calculated under the climate change effects. In the next step, the climate change effects on the water supply and demand were simulated using Water Evaluation and Planning model (WEAP), and its results were extracted so as the water management indexes. The results show that the temperature will increase in the future period under all three RCP scenarios (RCP2.6, RCP4.5 and RCP8.5) compared to the baseline period, while precipitation will decrease under the RCP2.6 scenario but will increases under RCP4.5 and RCP8.5 scenarios. Under the trend of changing in temperature and rainfall, the irrigation demand in the agricultural sector in all scenarios will increase compared to the baseline period. However, the inflow of reservoir will decrease under the RCP2.6 and RCP4.5 scenarios and will increases under RCP8.5 scenario. Evaluation of WEAP modeling results shows that the sustainability index of the entire Marun water-energy system will decrease in the future period compared to the baseline period under the RCP2.6, RCP4.5 and RCP8.5 scenarios by 13, 10 and 8%, respectively. The decrease in the system sustainability index shows that in the absence of early planning, the Marun water-energy supply system will face several challenges for meeting the increasing demand of water in different consumer sectors in the coming years.