HYDRAULIC MODELING OF THE FLOOD AREA IN NORTH-WESTERN KOSOVO THROUGH HEC-RAS SOFTWARE

Authors

DOI:

https://doi.org/10.58885/ijees.v11i1.41.fb

Keywords:

water resources, floodplain, HEC-RAS, hydraulic modeling, flood risk management, Kosovo.

Abstract

Flood risk assessment and delineation of flood prone areas are fundamental components of sustainable water resources management, especially in rapidly urbanizing river basins. In north-western Kosovo, the Sitnica River basin has experienced recurrent inundation events, exposing discrepancies between existing regulated design discharges and statistically derived extreme floods. This study develops an integrated hydraulic–legal assessment framework using one-dimensional (1D) and two-dimensional (2D) modeling with HEC-RAS (version 6.3.1) for floodplain delineation and public water asset definition under current national legislation.

Extreme value statistical analysis was conducted on a 21-year daily discharge record (1963–1985) at the Nedakoc station. The Gumbel distribution, complemented by comparative Log-Pearson Type III fitting, was used to estimate the 1 % exceedance probability discharge (Q₁%). Results show that the previously adopted design discharge of 239.76 m³/s underestimates the statistically derived Q₁% by approximately 95 % to 110 %, indicating significant hydraulic deficiency in the regulated river reach.

Unsteady 2D simulations highlight maximum flood depths up to 3.20 m and velocities up to 2.80 m/s in constrained morphological zones. A sensitivity analysis of roughness coefficients (±20 %) reveals a ±12 % variation in peak depths and ±8 % shift in inundation extent, underscoring model responsiveness to parameter uncertainty. Model calibration and validation against documented flood events (January 2021 and January 2026) yielded a Root Mean Square Error (RMSE) of 0.18 m and a Nash–Sutcliffe Efficiency (NSE) of 0.82, demonstrating good conformity between observed and simulated water levels.

The integrated hydraulic modeling approach provides a scientifically defensible basis for more reliable floodplain delineation and public water boundary definition under evolving environmental and regulatory conditions. Limitations include the relatively limited hydrological time series and absence of climate scenario analysis, which future work should address.

References

Amoussou, E., et al. (2024). Use of the HEC-RAS model for the analysis of exceptional floods in the Ouémé basin.

Brunner, G. W. (2016). HEC-RAS river analysis system – Hydraulic modeling concepts. USACE Hydrologic Engineering Center.

Chow, V. T. (1959). Open-channel hydraulics. New York, NY: McGraw-Hill.

El-Bagoury, H., & Gad, A. (2024). Integrated hydrological modeling for watershed analysis, flood prediction, and mitigation using meteorological and morphometric data, SCS-CN, HEC-HMS/RAS, and QGIS.

ESRI. (2018). ArcGIS desktop help: Spatial analysis and hydrologic modeling. Redlands, CA: Environmental Systems Research Institute.

European Parliament and Council. (2007). Directive 2007/60/EC on the assessment and management of flood risks. Brussels, Belgium.

Fetter, C. W. (2001). Applied hydrogeology (4th ed.). Upper Saddle River, NJ: Prentice Hall.

Fread, D. L., & Lewis, J. M. (1998). NWS FLDWAV model: Theoretical description. National Weather Service, NOAA.

French, R. H. (1985). Open-channel hydraulics. New York, NY: McGraw-Hill.

González-Cao, J., Barreiro-Fonta, H., Fernández-Nóvoa, D., & García-Feal, O. (2025). Enhancing flood risk management: A review on numerical modelling of past flood events.

Goodell, C. (2014). Breaking the HEC-RAS code: A user's guide to automating HEC-RAS. HEC Press.

Horritt, M. S., & Bates, P. D. (2002). Evaluation of 1D and 2D numerical models for predicting river flood inundation. Journal of Hydrology, 268(1–4), 87–99.

Knighton, D. (1998). Fluvial forms and processes: A new perspective. London, UK: Arnold Publishers.

Lucas, M., Lang, M., Renard, B., & Le Coz, J. (2024). A comprehensive uncertainty framework for historical flood frequency analysis: A 500-year-long case study.

MDPI Water. (2024). Flood risk prediction and management by integrating GIS and HEC-RAS 2D hydraulic modelling: A case study of Ungheni, Iasi County, Romania.

Ministry of Environment and Spatial Planning (MESP) / Ministry of Environment, Spatial Planning and Infrastructure (MMPHI). (2012). Environmental consent for the Business Park in Mitrovica (No. 12/1465/1-ZSP-159/12). Pristina, Kosovo.

Ministry of Environment and Spatial Planning (MESP). (2015). Administrative instruction No. 19/2015 on protection against harmful effects of waters. Pristina, Kosovo.

Ministry of Environment and Spatial Planning (MESP). (2016). Administrative instruction No. 05/2016 on regulating the status of water assets. Pristina, Kosovo.

Ministry of Environment, Spatial Planning and Infrastructure. (2023). Report on the review of requests for water resources (Protocol No. 4598/23). Pristina, Kosovo.

Municipality of Mitrovica. (n.d.). Municipal spatial development plans (MDP). Mitrovica, Kosovo.

Plate, E. J. (2002). Flood risk and flood management. Journal of Hydrology, 267(1–2), 2–11.

Republic of Kosovo. (2013). Law No. 04/L-147 on waters of the Republic of Kosovo. Pristina, Kosovo.

Rodhe, A., & Seibert, J. (2011). Groundwater dynamics in a till hillslope: Flow directions, gradients and delay. Hydrological Processes, 25, 1899–1909. https://doi.org/10.1002/hyp.7946

Teng, J., Jakeman, A. J., Vaze, J., Croke, B. F. W., Dutta, D., & Kim, S. (2017). Flood inundation modeling: A review of methods, recent advances and uncertainty analysis. Environmental Modelling & Software, 90, 201–216.

U.S. Army Corps of Engineers. (2016). HEC-RAS river analysis system: User’s manual (Version 5.x). Davis, CA: Hydrologic Engineering Center.

U.S. Army Corps of Engineers. (2016). HEC-RAS river analysis system: Hydraulic reference manual. Davis, CA: Hydrologic Engineering Center.

U.S. Army Corps of Engineers. (2019). HEC-RAS 2D modeling user’s manual. Davis, CA: Hydrologic Engineering Center.

Ullah, M. I., Qureshi, K. S., Rauf, A. U., et al. (2024). Advanced floodplain mapping: HEC-RAS and ArcGIS Pro application on Swat River.

UNESCO, & World Meteorological Organization. (2012). Managing flood risk: Integrated flood management. Paris, France / Geneva, Switzerland.

World Bank. (2014). Urban flood risk management: A tool for integrated flood management. Washington, DC: World Bank.

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Published

2026-03-06 — Updated on 2026-04-24

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How to Cite

Fidan Bilalli, & Aida Bode. (2026). HYDRAULIC MODELING OF THE FLOOD AREA IN NORTH-WESTERN KOSOVO THROUGH HEC-RAS SOFTWARE. International Journal of Earth & Environmental Sciences (IJEES), 11(1), 41–57. https://doi.org/10.58885/ijees.v11i1.41.fb (Original work published March 6, 2026)

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