The Impact of Spatiotemporal Changes in Land Development (1984–2019) on the Increase in the Runoff Coefficient in Erbil, Kurdistan Region of Iraq

Abstract

Nowadays, geospatial techniques are a popular approach for estimating urban flash floods by considering spatiotemporal changes in urban development. In this study, we investigated the impact of Land Use/Land Cover (LULC) changes on the hydrological response of the Erbil basin in the Kurdistan Region of Iraq (KRI). In the studied area, the LULC changes were calculated for 1984, 1994, 2004, 2014 and 2019 using the Digital Elevation Model (DEM) and satellite images. The analysis of LULC changes showed that the change between 1984 and 2004 was slower than that between 2004 and 2019. The LULC analysis revealed a 444.4% growth in built-up areas, with a 60.4% decrease in agricultural land between 1984 and 2019. The influence of LULC on urban floods caused by different urbanization scenarios was ascertained using the HEC-GeoHMS and HEC-HMS models. Over 35 years, there was a 15% increase in the peak discharge of outflow, from 392.2 m3/s in 1984 to 450 m3/s in 2014, as well as the runoff volume for a precipitation probability distribution of 10%, which increased from 27.4 mm in 1984 to 30.9 mm in 2014. Overall, the probability of flash floods increased in the center of the city due to the large expansion of built-up areas.

Comparative Analysis of Developed Rainfall Intensity–Duration–Frequency Curves for Erbil with Other Iraqi Urban Areas

“…Mustafa et al [33] presented extreme rainfall events as a cause of urban flash floods in Erbil. Moreover, according to Mustafa and Szydłowski [34,35], the city's urbanization is causing an increase in runoff peak and volume. As a result, the possibility of flash floods increases, posing a risk to life quality in the studied area, particularly in the city center.…”

Towards a multi-basin SWAT model for the migration of nutrients and pesticides to Puck Bay (Southern Baltic Sea)

“…The model was set up using the QGIS SWAT interface. The resolution of the used DEM is 10 m ( Kalinowska et al, 2018 ; Mustafa & Szydłowski, 2020 ). The basin boundaries determined on the basis of the DEM were compared with topographic and hydrological maps and were also verified by fieldwork ( Fig.…”

Driving Factors of Heavy Rainfall Causing Flash Floods in the Middle Reaches of the Yellow River: A Case Study in the Wuding River Basin, China

“…Using meteorological, hydrological, land-use, topographic, and other data to determine the conditions and influencing factors of flash floods, they have found that precipitation is the direct driving factor that induces flash floods [26][27][28], and have reported that the process of flash flood disasters is the continuous transformation of material and energy from the sky to the ground, from slopes to gullies, and from river branches to the trunk [29][30][31][32][33] Through the analysis of typical mountain torrent disaster events, the temporal and spatial distributions of the occurrence of mountain torrents in different regions have been identified [34], the relationships between the disaster-causing factors and the occurrence of mountain torrents has been revealed, and it has been demonstrated that mountain torrents are caused by the combined action of a disaster-pregnant environment and disaster-causing factors. They are affected by disaster-pregnant environmental factors such as the hydrometeorology, topography, landforms, urbanization, and land use in hilly areas [35,36]. The intensities of heavy rainfall and flash floods exhibit strong spatial and temporal variability: the rainfall range is small, the intensity is large, the flood process is short, the flood peak is high, and the destructive force is strong [37].…”