Shatt Al-Hilla branches from the left of Euphrates River, U/S Hindiyah Barrage, Iraq, and extends about 100 km. It branches at the end into Shatt Al-Diwaniya 112 km and Shatt Al-Daghara 64 km. The study aims to evaluate and develop (Hilla-Daghara) rivers system, which is included Shatt Al-Hilla and Shatt Al-Daghara. Fieldwork began from (26 October until December) 2020. M9, S5 devices, and the installed staff gauges were used to measure discharges and water levels, respectively. A one-dimensional model was developed for the study area by HEC-RAS, after calibration and verification by field measurements; the Manning's n of Shatt Al-Daghara is found to be 0.022. Five Scenarios were simulated to study the reach under the current conditions. It was found that the discharge capacity in Shatt Al-Hilla and Shatt Al-Daghara is 200 m3/s and 50 m3/s, respectively. Four scenarios were conducted for the development to improve the capacity of Shatt Al-Hilla to 303 m3/s and Shatt Al-Daghara to 75 m3/s. Earthworks volume of development Shatt Al-Hilla and Shatt Al-Daghara are about (5.89 and 0.54) Mm³, and its cost is (11.780 and 1.080) billion IQD respectively. Results of applied development show that Shatt Al-Daghara tail can pass discharge more than five m3/s when Shatt Al-Daghara tail cross regulator that causes choking in the last reach of Shatt Al-Daghara is removed.
