A game theoretic approach for interbasin water resources allocation considering the water quality issues

River water quality management using an integrated multi-objective optimization-simulation approach based on bankruptcy rules

The aim of this research is to allocate the river's self-purification (acceptance capacity of pollution) fairly between the beneficiaries (pollutant sources) using bankruptcy theory. For this purpose, four bankruptcy rules (CAE, CEL, P, and TAL) were called using the link of the water quality simulation model (QULA2Kw) to an evolutionary optimization algorithm (multi-objective imperialist competition algorithm (MOICA)). The objective functions were reducing polluters' wastewater treatment costs and preventing biochemical oxygen demand (BOD) violations of the standard level along the river. The applicability of the approach is demonstrated by the case study that was carried out on the Dez River in Iran. According to the results, the CEL scenario is the most effective method for the Dez River when taking into account the most optimal state for both objective functions (selecting the best compromise solution from the Pareto front). This is because it has the lowest violation value of the standard level for BOD along the river when compared to other scenarios. Alternatively, when considering Solution 20, which focuses on the maximum cost of treating the polluters while staying within the acceptable level of pollution in the river, the results indicated that the CEA rule emerged as the most favorable option. This is due to its lower treatment cost (156.9 (1000$)) and higher pollution discharge to the river (681.91 g/s).

A market-based mechanism for long-term groundwater management using remotely sensed data

Groundwater markets improve the agricultural economy by transferring water entitlements from low-efficient users to high-efficient ones to maximize productivity. Aiming at developing an efficient groundwater market, the environmental effects of the market mechanism should be assessed, and a reliable method for monitoring water consumption needs to be employed. Toward this end, this paper proposes three annual smart groundwater market mechanisms to maximize water net benefits, minimize groundwater withdrawal, and precisely measure water consumption in agricultural fields. To guarantee the aquifer's safe yield in each mechanism, a groundwater simulation model (i.e., Groundwater Modeling System (GMS)) is used to control groundwater table drawdown at the end of the planning horizon. In addition, the fields' evapotranspiration (ET) is estimated using Surface Energy Balance Algorithm for Land (SEBAL) and Mapping Evapo Transpiration at high Resolution with Internalized Calibration (METRIC) algorithm to measure the net groundwater consumption during the market. In this regard, we evaluated the algorithms' performances using observed data from a local lysimeter. They are applied to the Nough plain in Iran to assess the effectiveness of the proposed market framework. The findings illustrate their efficiency in recovering approximately 80% (23.33 million cubic meters (MCM)) of groundwater loss due to overexploitation in the study area and increasing the users' annual benefits by 10.6% compared to the non-market condition. In addition, results imply that the METRIC model approximates daily crop ET with a higher accuracy level than the SEBAL model with RMSE, MAE, and Percentage Error of 0.37 mm/day, 0.32 mm/day, and 14.92%, respectively. This research revealed that the proposed market framework is a powerful tool for reallocating water entitlements and increasing water productivity in arid and semi-arid regions.

Reservoir Operation Sequence- and Equity Principle-Based Multi-Objective Ecological Operation of Reservoir Group: A Case Study in a Basin of Northeast China

The sequence of reservoir operations has a profound influence on the regulation and storage capacity of reservoir groups to effectively utilise the natural water inflow and external water transfer in the basin, especially for reservoir groups with water supply tasks. This study establishes the reservoir operation sequence (ROS) of four reservoir group modes, aiming at national economic and ecological water consumption, constructs a model of ROS-based multi-objective ecological operation of the reservoir group, and uses the particle swarm optimisation (PSO) method to optimise the solution. Analysing the results of the three schemes in two scenarios at the Yinma River Basin (YRB) indicates that after the Central Jilin Water Supply Project is put into operation, not only will the production and living water be effectively improved, but also the ecological water in the basin. Then, we compared the optimisation results of different water supply sequences in series and parallel reservoirs, which illustrates that the ROS of the four modes formulated in this research is the optimal water supply sequence.

Tradeoff for water resources allocation based on updated probabilistic assessment of matching degree between water demand and water availability

Water resources allocation is very important for water resources management. However, it is subject to the uncertainty in water availability (WA) or water demand (WD), as well as the pressure exerted by multi-stakeholders. Therefore, we propose a general framework as following: (i) applying Bayes theorem to develop a forecasting model for WA and WD probability distributions; (ii) constructing the matching matrix showing matching degree between WA and WD and assessing the probabilistic behavior of water resources allocation solutions based on the matching matrices; and (iii) performing the trade-off analysis among the solutions under different stakeholders' objectives to meet requirements of multi-stakeholders. Longgang River basin is selected as a case study area to demonstrate the proposed framework. Results show that, the forecast probability distributions of WA and WD may be updated timely with newly introduced data, and reflect their statistical characters well. Furthermore, the matching matrices illustrate the probabilities of the possible outcomes of each allocation solution clearly. From the probabilistic assessment; the results suggest: 21160×10⁴ m³ diverted water are required to surely satisfy the current water demands, which is exactly the amount currently diverted for the study area. The proposed framework provides the updated probabilistic assessment for the possible outcomes, contributing to stakeholders to perform the tradeoff with each other. It makes significant contributions to address water allocation issues under uncertainty and is worthy to be applied broadly.

A Game Theory-Based Approach for Exploring Water Resource Exploitation Behavior in the Poyang Lake Basin, China

Exploring the relationship between competition and cooperation in water resource exploitation by applying a game model is crucial for achieving stable equilibrium in the presence of environmental externalities. To explore this, we used the Poyang Lake Basin, which is divided into three overly exploited sub-regions, as an example. This paper selected the different types of sub-regions of Poyang Lake Basin as the research subjects, and then proposed a game model to study evolutionarily stable equilibrium strategies. The results are as follows: (1) the behavior of the sub-regions of Poyang Lake Basin are affected by one another and cannot achieve equilibrium through independent games, which also need external forces to coordinate the three reaches; (2) the benefits improve gradually from the state of “non-cooperation” to “full cooperation” and reach an ideal equilibrium when all the sub-regions choose the strategy of cooperation; (3) the strategic choice of sub-reaches is difficult to maximize the overall benefits of the basin in the absence of external constraints. To ensure that the sub-regions choose the cooperative strategy, the central government should support the cooperative subsidies of local governments. In addition to improving the equilibrium state of the sub-reaches, this study proposes the following policy implications: constructing a basin plan and promoting fiscal transfer payments, inducing an industrial gradient transfer, and strengthening the payment for the use of water resources.

Cooperation control strategies for China's cross-region pollution in a lake basin based on green reduction cost

The cross-region water pollution issue has always been the widespread concern around the world. It becomes especially critical for China due to the imbalance relates to environmental costs that have accompanied rapid growth of economy. Though the government makes great efforts to improve it, the potential for water pollution conflict is still great. We consider the problem of determining combined control strategies for China's cross-region lake pollution based on the environmental green costs. The problem is first formulated as a generalized bilevel mathematical program where the upper level consists in each region that reduces environmental green costs including three parts: the reduction cost, pollution permit trade cost and cost of environment damage, while the lower level is represented by pollution permit equilibrium market. Finally, we take an empirical analysis in Taihu lake. The numerical study shows that the minimum costs of both total and regional are obviously superior to the current processing costs, which provides theoretical basis for the price of emission permits.

IMPLICATIONS

Today, China's rapid gross domestic product (GDP) growth has come at a very high cost, as real estate prices have skyrocketed, the wealth gap has widened, and environmental pollution has worsened. China's central government is urged to correct the GDP-oriented performance evaluation system that is used to judge administrative region leaders. The cross-region water pollution issue has become a troubling issue that urgently needs to be resolved in China. This paper will not only actively aid efforts to govern Lake Taihu and other cross-region valleys, but it will also provide a supplement for theoretical research on cross-region pollution issues.

Simulating water markets with transaction costs

This paper presents an optimization model to simulate short-term pair-wise spot-market trading of surface water abstraction licenses (water rights). The approach uses a node-arc multicommodity formulation that tracks individual supplier-receiver transactions in a water resource network. This enables accounting for transaction costs between individual buyer-seller pairs and abstractor-specific rules and behaviors using constraints. Trades are driven by economic demand curves that represent each abstractor's time-varying water demand. The purpose of the proposed model is to assess potential hydrologic and economic outcomes of water markets and aid policy makers in designing water market regulations. The model is applied to the Great Ouse River basin in Eastern England. The model assesses the potential weekly water trades and abstractions that could occur in a normal and a dry year. Four sectors (public water supply, energy, agriculture, and industrial) are included in the 94 active licensed water diversions. Each license's unique environmental restrictions are represented and weekly economic water demand curves are estimated. Rules encoded as constraints represent current water management realities and plausible stakeholder-informed water market behaviors. Results show buyers favor sellers who can supply large volumes to minimize transactions. The energy plant cooling and agricultural licenses, often restricted from obtaining water at times when it generates benefits, benefit most from trades. Assumptions and model limitations are discussed.

KEY POINTS

Transaction tracking hydro-economic optimization models simulate water marketsProposed model formulation incorporates transaction costs and trading behaviorWater markets benefit users with the most restricted water access.

Optimal water and waste-load allocations in rivers using a fuzzy transformation technique: a case study

In this paper, a new methodology is developed for integrated allocation of water and waste-loads in river basins utilizing a fuzzy transformation method (FTM). The fuzzy transformation method is used to incorporate the existing uncertainties in model inputs. In the proposed methodology, the FTM, as a simulation model, is utilized in an optimization framework for constructing a fuzzy water and waste-loads allocation model. In addition, economic as well as environmental impacts of water allocation to different water users are considered. For equitable water and waste load allocation, all possible coalition of water users are considered and total benefit of each coalition, which is a fuzzy number, is reallocated to water users who are participating in the coalition. The fuzzy cost savings are reallocated using a fuzzy nucleolus cooperative game and the FTM. As a case study, the Dez River system in south-west of Iran is modeled and analyzed using the methodology developed here. The results show the effectiveness of the methodology in optimal water and waste-loads allocations under uncertainty.