Development of a model for the water harvesting according to natural conditions appropriate structures

The purpose of soil management is maximizing the supply of water and nutrients to the plant and minimizes the soil erosion, improve soil fertility and soil physical conditions. Using in-site water harvesting methods reduces runoff from the area and increases the water stored in the soil profile. Rainwater harvesting is not a new concept, but it requires the combination of native methods with modern knowledge. Because the used technology was inappropriate for special conditions of the region, some water harvesting projects have been unsuccessful or even led to the loss of the whole crop. The suitability of an area for rain water harvesting depends on its ability to supply the technical and basic needs of the system. This study introduces a method for rain water harvesting in the area with little slope or no slope, which can be Mechanized Construction for large-scale. On the other hand, a computer simulation has been preparation and introduced for precise and scientific designing of a water harvesting system, which there has not been much effort in this case. The results of simulation indicated the reduction of concentration ability of water by Kajaweh system with decreasing the size of structure. In addition, in relatively smaller sized structures under high intensity rainfall, reduction of water concentration ability by Kajaweh system was predicted by simulation. Such trend is also expected for long time rainfall times (especially in low rainfall intensity).