A
s one of the main water saving irrigation technologies, sprinklers irrigation systems are used globally owed to the advantages like wide adaptability and easily automated operation. Sprinkler application uniformity is an important indicator in the evaluation of design irrigation quality. HEDIA mode has been instated to select the more acceptable design of sprinklers geometric overlapping pattern depending upon Christiansen uniformity coefficient. The model used one sprinkler superimposition technique and double cubic spline interpolation method in generating the overlapping pattern water data. HEDIA computer model has been validated by CATCH3D model Version 4.6. Their results indicated that CATCH3D model can't accurately calculate the even triangular sprinklers overlapping pattern shape data and failed in predicting sprinkler water distribution pattern from several radii data additionally the difficulty use of that model. Conversely, HEDIA has been succeeded in simulating all sprinklers overlapping patterns shapes from grid or radial data. The created model can use just one quarter part sector or one radial data in generating the sprinkler distribution pattern data in lab test then directly applicant the overlapping patterns calculations with simplicity deal. So, HEDIA computer model can serve as a decision support model in designing sprinklers overlapping patters.