In this paper, a simple irrigation pipeline system is proposed to represent the common situation of lifting water from a reservoir to another higher reservoir through a pipeline. Bentley HAMMER model is used to perform simulation and analysis of steady state and transients in the irrigation pipeline system. To protect the irrigation pipeline system against positive and negative hydraulic transient pressures due to power failure, a hydro pneumatic tank is employed. The diameter, liquid and tank volumes are studied versus max pressure and vapor volume affecting the irrigation pipeline system. It is concluded that decreasing the diameter till 1/6 times the pipeline diameter, the max pressure decreases. More decreasing the diameter, the max pressure increases. Decreasing the diameter till 1/4 times the pipeline diameter, no vapor is formed. More decreasing the diameter, the vapor exists. As the liquid volume decreases; the max pressure increase for each value of the diameter, while the vapor increases for the diameters less than or equal 1/6 times the pipeline diameter. The time after which check valve of pump closes varies according to the diameter and liquid volume. Design chart and nine design equations are obtained to get easy and effective design for hydro pneumatic tank. Employing the deduced design chart or the obtained design equations accomplish savings 55% in the diameter and 51% in liquid and tank volumes for the hydro pneumatic tank.

There are many challenges to be faced in order to achieve the optimum use of available resources against the increasing food and other demands of the world population with the shrinking resources. Optimization can be considered as the ensemble of steps which must be taken to find the minimum, or maximum, of a function that is usually called an objective function. This paper provides snapshots of research and practical implementation of optimum design concepts and criteria of surface irrigation systems. Technical papers and reports are reviewed addressing challenges and different aspects of this issue, in addition to optimum allocation systems of surface water and ground water. It is concluded that the optimum irrigation may be defined more broadly as maximization of overall benefits, including nonmonetary benefits as water quality protection, food security, increased employment, and resettlement of populations. Linear programming, dynamic programming and genetic algorithms techniques are still very popular to get optimal surface irrigation systems. Surface irrigation parameters identification represents an important way to get optimal surface irrigation systems. Optimal conjunctive use of surface and ground water resources may be needed in some cases, such as water deficits in arid and semi-arid regions and uncertainty.

Ain Sukhna has become one of the most important economic areas in Egypt recently. As a result of this economic development, the demand for water has increased, with special emphasis on groundwater. Therefore, in this paper, several scenarios are assessed in order to reach the best scenario for groundwater management giving the opportunity to achieve the development needs of that region.Groundwater Modeling System (GMS) software is used to construct the solid model forsimulating the geometry of the aquifer layers. Then, a conceptual model is developed and calibrated in steady state case. The calibration results are satisfactory showing a good agreement between the calculated and observed heads. Finally, four scenarios are simulated with different pumping possibilities ranging from -25% to + 50% of the current pumping rates. The results show that it will be better if the current pumping rate is reduced by 25% which can make the drawdown values less than the other possibilities. It is also shown that the best recommended places to drill more wells can be in the east and south directions where the least drawdown values are found.

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Mit Kenana area, 40 km North of Cairo, represents the eastern fringes of the Nile Delta in Egypt. Existing laterals spacing design of Mit Kenana area is reviewed. Then spread sheets are employed to obtain laterals spacing, which is referred to as spread sheet design. Microsoft Excel software, as instance for spread sheets, is employed to get the laterals spacing design of steady state subsurface drainage systems. The most suitable and popular Hooghoudt equation is used to get the spacing L, including the equivalent depth. Given data are depth to the impermeable layer, radius of the pipe lateral, hydraulic conductivities of the soil above and below drain level, elevation of the water table midway between the drains, and drainage rate. The lateral spacing L is assumed. Calculations are done through the spread sheet and the final result of L is obtained. Check for the obtained L is established with respect to the assumed value. Also, another check is employed for the equivalent depth d e. Almost identical results are accomplished by spread sheet design compared with the existing design. Laterals spacing design for steady state subsurface drainage systems employing spread sheets is efficient, accurate, quick, easy and simple.