Rainwater Harvesting Analysis

Due to the water scarcity problem especially in drought areas such as Iraq the ecological technique of rain water harvesting is promising. This technology summarises by collecting storing and conserving local surface runoff for agriculture domestic industrial and environmental purposes. This book contains the analytical study of the main climatic factors affecting rainwater harvesting system for agricultural purpose according to the ratio of catchment to cultivated area for irrigation of tomato crop. This factor represent the effect of rainfall temperature wind speed actual daily sunshine and relative humidity. Three climatic zones in Iraq were selected these are Zubair area south of Iraq Debaga area north east of Iraq and Tall'Afar area north west of Iraq. Statistical method of Gumbel distribution of extreme values was used for series of annual rainfall to determine the design rainfall. The water consumption factor calculated using Blaney-Griddle formula. The runoff coefficient and efficiency factor are estimated according to soil properties. Finally the catchment to cultivated area ratio calculated according to these factors and DR with using five return periods.