灌溉排水系统工程

Transportation Module Determination for the Urban Landscapes with Linear Programming Pattern in the Urmia, North-West Iran

Abstract

Solmaz Javanbakht and Reza Dadmehr

Urban landscapes are the crucial key factors in natural human life stability in modern urban civilization. However, despite of the importance of urban landscape, common suitable urban landscape per capita in cities of Iran is between 7 to 12 square meters and the average urban landscape per capita in Urmia metropolis is 6.9 square meters, which indicates a serious gap for 20 to 25 square meters as global standards. On the other hand, the urban landscape growth for achieving global standards causes an increase in vegetation which by itself results in greater demand for water resources. Consideration of arid and semi-arid climate of Iran and limitation in water resources makes urgent need for planning and water allocation. The main purpose of the this study is putting forward a linear programming pattern in the form of transportation model in-order to allocate water optimally from the existing and future water resources (i.e., surface water, ground water and drinking water) to Urmia urban landscape pieces, considering minimization of the cost of supplying water. To achieve the above mentioned model, North-West Corner method, Least Cost method and Vogal Approximation method have been applied and the obtained results have been compared. According to the obtained results, in summary, it can be claimed that Vogal Approximation method, has the higher capacity for optimal allocation of water resources in Urmia urban landscape than that of Least Cost method as well as North-West Corner methods With regard to the present availability of water resources for every seven months of irrigation, the amount of optimal allocation of water from drinking water is 5400 cubic meters per day for boulevards, 1400 cubic meters per day for nurseries and 1200 cubic meters per day for other landscapes. The allocated optimal amount of water from surface water resources is 6500 cubic meters per day for forest parks. The allocated amount of ground water resources is 5000 cubic meters per day for parks in urban areas and 1600 cubic meters per day for boulevards and 900 cubic meters per day for forest parks. During the hottest month of each year (June 22nd to July 14th), with respect to irrigation, given the above variables in optimal allocation of water resources for urban landscape in the city of Urmia in comparison with that of seven month irrigation, are the same. However from quantity point of view, drinking water and ground water quantity, in some landscapes are less. Also, concerning the optimal allocation of water from future water resources (increment water supply), given variables such as mentioned above are present in the existing conditions. However, the quantity of groundwater usage for some landscapes is more. Finally, through the aforesaid allocation, only a portion of water demand for the pieces of Urmia landscapes has been partially met and the existing water resources would not be sufficient to bridge the gap.