ANALYSIS OF THE HYDRAULIC CHARACTERISTICS OF AL MAHAWIL STREAM USING HECRAS: A FIELD STUDYATHEER ZAKI MOHSIN ALQAISI AND RUSUL IHSAN ABDULRIDHAAbstract A water resources management for earthen canal/stream is introduced through creating a combination procedure between a field study and the scientific analytical concepts that distinguish the hydraulic problems on this type of stream with using the facilities that are available in HECRAS software; aiming to point the solutions of these problems. Al Mahawil stream is an earthen canal which is subjected to periodic changes in cross sections due to scour, deposition, and incorrect periodic dredging processes due to growth of the Ceratophyllum plants and weeds on the bed and banks of the stream; which affect the characteristics of the flow. This research aims to present a strategy of water resources management through a field study that conducted to analyse the hydraulic characteristics of this stream. The flow in the stream is simulated by one dimensional steady flow mathematical model using HECRAS software with three cases; case1 (design); case2 (actual); and case3 (without impermissible fish lakes). The flow characteristics are analysed as a steady gradually varied flow. The verification of the HECRAS program is carried out through field works. The results showed that the Al Mahawil stream is sufficient for irrigation purposes of the design case; while there is a fluctuation in the flow characteristics, and deficit in the discharge in the other cases. It is concluded that the control on the illegal watercourse, water plants, and fish lakes and redistribution them along this stream are the justified ways that insure the justice distribution of water and avoid the conflicts among farmers. |