Evaluation of the rain water network in wasit governorate/Kut city and the commercial center of the region as a dual network (rain and sewage).

Urbanization and climate change are the primary causes of urban flooding, which is accompanied in some regions by wastewater pollutants as a result of residential wastewater that illegally connected to the storm water system. This paper focuses on evaluating the performance of storm water network as a combined drainage network located in center of Iraq using the Storm Water Mangment Model after appropriate calibration and validation. The Intensity-Duration-Frequency curves for Kut city were applied to the obtained rainfall data. The IDF curves were for 5-hour storms with 30-minute time intervals and return periods of 2, 10, 25, and 50 years. For infiltration processes and flow routing, the Curve Number model and the dynamic wave approach were employed, respectively. The percentage of flooded nodes in different places in Storm Water Mangment Model with proportions of 56.3, 67.1, 70.9, and 74.7% for combined network were noticed from the Storm Water Mangment Model simulation results for return periods of rainfall of 2, 10, 25, and 50 years, respectively. [ABSTRACT FROM AUTHOR]