Sergei Schreider

Economic Sharing of Basin Water Resources between Competing Stakeholders

This paper describes an application of linear programming (LP) methods for optimal allocation of water among competing stakeholders that would achieve the highest economic return from water use in the agricultural section of the Sefidrud Basin, northern Iran. In a network presentation of the basin, the nodes stand for the supply and demand points and arcs represent reaches. The constraints of the LP model are the network structure of the basin (flows, stream geography and channel capacity), the available surface and ground water in each node, the environmental demand in different reaches, upper and lower bands of supply in each node and water balances. Optimal policies are derived for current and future demand. The optimal policies indicate that, at present, the basin water resources satisfy the demands of all stakeholders. Although, the results show that there is no conflict for supplying stakeholders’ current demands, they indicate that the current proportion of surface water used is not optimal compared with the proportion of ground water used. The results also indicate that some future demands of provinces with lower marginal value of water are unsatisfied and that this could cause conflict between stakeholders. Since in some nodes the optimal solutions suggest using surface water even where they have available ground water, they are categorized as having a higher possibility to construct dams in the basin.

A Multi-objective Approach for Transboundary River Water Allocation

The allocation of water to the stakeholders of a large basin involves conflicting objectives, since increasing the allocated water to one stakeholder leads to a reduction in water allocated to other stakeholders. The consideration of conflicting objectives is inevitable when the basin is a transboundary basin, where a river crosses at least one political border, either a border within a nation or an international boundary. This paper proposes a multi-objective optimization model for sharing water among stakeholders of a transboundary river, assuming that the stakeholders cooperate. Here, the cooperation implies a balanced water allocation to stakeholders since shortage in each stakeholder have negative impacts on others. Each objective function of the multi-objective model represents the water profit of a stakeholder; which has to be maximized. To reach a cooperative solution, a new method for transforming the multi-objective formulation to a three-step single objective formulation is proposed. The solution guarantees each stakeholders profit which is larger than a percentage of its highest possible profit obtained in the case when the percentage of profit is equal for all stakeholders. The proposed model formulation was applied to the Sefidrud River where eight provinces are the stakeholders competing for water resources of this basin.

Game theoretic approach for fertilizer application: looking for the propensity to cooperate

This paper continues the research implemented in previous work of (Schreider et al. in Environ. Model. Assess. 15(4):223–238, 2010) where a game theoretic model for optimal fertilizer application in the Hopkins River catchment was formulated, implemented and solved for its optimal strategies. In that work, the authors considered farmers from this catchment as individual players whose objective is to maximize their objective functions which are constituted from two components: economic gain associated with the application of fertilizers which contain phosphorus to the soil and environmental harms associated with this application. The environmental losses are associated with the blue-green algae blooming of the coastal waterways due to phosphorus exported from upstream areas of the catchment. In the previous paper, all agents are considered as rational players and two types of equilibria were considered: fully non-cooperative Nash equilibrium and cooperative Pareto optimum solutions. Among the plethora of Pareto optima, the solution corresponding to the equally weighted individual objective functions were selected. In this paper, the cooperative game approach involving the formation of coalitions and modeling of characteristic value function will be applied and Shapley values for the players obtained. A significant contribution of this approach is the construction of a characteristic function which incorporates both the Nash and Pareto equilibria, showing that it is superadditive. It will be shown that this approach will allow each players to obtain payoffs which strictly dominate their payoffs obtained from their Nash equilibria.

Sensitivity analysis of gas supply optimization models

The security of gas supply is a crucially important question for the economy of any country. South-eastern Australia has a sophisticated network of gas pipelines that connect the production sites on the ocean shelf and in the inner part of the continent with the major consumers, which are the state capital cities (Adelaide, Melbourne, Hobart, Sydney and Brisbane) and the regional industrial town of Gladstone. Two optimization models were developed in order to test the security of the gas supply system against possible global impacts that affect the demand for natural gas. The modeling research in the present work was focused on the simulation of delivery when demands reach their peak values. The first model minimizes squares of shortfalls in major supply nodes. As major constraints the models used the production levels, supply capacities and the mass balance in pipe junctions. The second model minimizes the total cost of gas delivery, which is a sum of production and transportation costs, while the constraints stay the same. Both models were run for a series of plausible economic scenarios which generated the future values of demand. The potential “bottle necks” in the system components were identified. It was found that the first constraint which became scarce is the pipe providing gas to the port of Gladstone. The capacity of this pipe should be increased in order to meet growing demand. Gladstone is also the site of the liquefied natural gas export industry on the east coast. An increase in pipeline capacity will facilitate the increase of export from Gladstone, but will reduce supply to other consumption nodes. A sensitivity analysis (SA) was implemented for both formulations of the model. The objective was to examine how the key indicators of system security and pipeline flow were impacted by changes (increase and decrease) in peak demands. For this analysis the predicted annual scenarios for peak demand increase for four states (ACT was treated as part of NSW in the present work) were used. For the analysis of the decrease of demand, proportional changes of the same magnitude in demand were used for all demand nodes. It can be concluded that with the current infrastructure the most vulnerable components of the system are industrial gas users in Gladstone and Mt. Isa, whereas amongst the domestic consumers it is Brisbane. This conclusion can be utilized in further decisions on pipeline infrastructure upgrades.

Trends and Variability in Droughts in the Pacific Islands and Northeast Australia

AbstractDrought is a recurrent climate feature of the Pacific Islands and northeast Australia with meteorological and socioeconomic impacts documented from early European settlement. In this study, precipitation records for 21 countries and territories in the Pacific for the period 1951 to 2010 have been examined to identify trends in drought occurrence, duration, and magnitude. The strength of the relationships between the main climate drivers in the Pacific—El Nino–Southern Oscillation (ENSO), the interdecadal Pacific oscillation (IPO), and the Pacific decadal oscillation (PDO)—and precipitation has been also examined. Station-scale drought trends are largely positive, but the majority are statistically nonsignificant with the significant trends mainly in the subtropics. Spatially, trend patterns are largely heterogeneous. A significant relationship between the oceanic component of ENSO and precipitation is confirmed for a large part of the Pacific Islands and eastern Australia with a strong lagged rela...

Determining Location and Capacity of Dams through Economic and Environmental Indicators

Construction of dams is a conventional way to deal with the problem of water scarcity in undeveloped basins. The economic and the environmental effects of dams are often evaluated locally rather than in a basin frame. The distinctive feature of this paper is to propose a basin-wide approach, comprised three steps for determining dams’ locations and dams’ capacities based on optimization modelling. Our approach provides an environmentally sound plan for surface water development that also results in the highest profit for the basin, for the sake of achieving sustainable development. The first step of our approach runs a mixed-integer linear model to give optimal locations and capacities of new dams for various number of dams along with satisfying the environmental water requirements in the entire basin. The second step uses a sensitivity analysis to finalize the number of dams in the basin by comparison of the basin profits, given by the various number of dams. Finally, the third step of the algorithm investigates the possibility of dams’ capacities reduction, for the selected number of dams while they still provide the same basin profit, given from the first step, using another mixed-integer linear model. The introduced approach was applied to the Sefidrud Basin, Iran and its results showed that three dams could lead to an environmentally sound sustainable economic development for the Basin.

Optimisation of gas flows in South Eastern Australia via controllable Markov chains

We consider the optimal flows of intra-day gas supply for the production and pipeline network for Adelaide, Melbourne and Sydney. We model the demand in the network of three major cities as a system of connected three state Markov chains subject to shortfall, pipeline capacity and production capacity constraints. A comparison with a static optimisation model is provided to show the improved capacity for the analysis of demand satisfaction in this model.