Feasibility study of the choice of pipe parameters and wastewater transportation system for irrigation on the example of the administrative district of Kerbala (Iraq)
The reuse of treated wastewater was adopted to solve the problem of water scarcity for irrigation of agricultural land in the administrative district Kerbala, Iraq, was decided. The quality of water meets the requirements for irrigation of agricultural plants. The first variant is old treatment structures with a capacity 1.16 and the second one - 4.63 m<sup>3</sup>/s (old and new treatment structures). The feasibility development is based on determination of the optimal diameter and material of pipes for both variants, taking into account the reduction in the transportation cost to the destination site using WaterCAD V8i model. The choice was made between pipes made of the following materials: ductile cast iron, glass plastic GRP, concrete and plastic. The hydraulic calculations of the operation of the irrigation water supply system have been made. The results of calculations showed that a plastic pipe with diameter 1000 mm is optimal for the first variant and a diameter 2000 mm - ductile cast iron - for second one. This is the first consideration of recycle treatment of wastewater to solution the food, social and economic problems of the region. Also at the first time the scheme for main pipeline routing for irrigation reuse of wastewater is proposed.