Many authors and researchers examined and tested several methods and tools for improving the performance efficiency of the culverts. Owing to increase the importance of the desert roads nowadays for joining the new constructed industrial and agricultural communities all over Egypt, and because of the draught nature of that new desert areas, for which the desert road network was constructed, and the possibility of the harmful and destructive impact of the torrents and flash floods periodically occurs in such regions, our present work will be focusing on the under-desert road culverts. The role of the under-desert road culverts is the prime factor in the constructional, and traffic safety of such roads. Its efficiency in converting the accumulated flash water from one side of the road to the other side at a significantly very short time protects the roads against failure due to overlapping. The present work introduces a new constructional simple tool for maximizing the discharging efficiency of the under-desert road culverts and ensuring its constructional safety in addition to the safety of the traffic over them. The introduced tool (as the best of our knowledge) wasn't investigated yet, or technically examined by any of the authors reviewed in the literature. 10 models of the inclined headwall with different inclination angles in the same direction of the stream flow, and in the opposite direction were tested. The optimum inclination angle which gives the maximum discharge under the minimum U.S. water head, for more safety of desert road against flash floods and torrents was introduced.