Date of Award
2025
Degree Type
Thesis
Degree Name
Master of Science in Biological and Environmental Sciences (MSBES)
Department
Geosciences
First Advisor
Soni M Pradhanang
Abstract
Flooding in Jayapura is a common occurrence due to high rainfall, steep slopes, and rapid urbanization, all of which have altered natural drainage systems and reduced the capacity of floodplains. As such, this study aimed to develop a flood hazard assessment for better management of the Acai River, Jayapura. The research combines hydrologic and hydraulic modeling using the US Army Corps of Engineers, Hydrological Engineering Center-Hydrological Modeling System (HEC-HMS), HEC-River Analysis System (HEC-RAS), and GIS platforms, together with empirical methods such as the Rational and Nakayasu Synthetic Unit Hydrograph (SUH) methods. Design storms of 2, 5, 10, 20, 50, and 100 years of return period were extrapolated through statistical frequency analysis methods. Additionally, a 24-hour design storm was developed using Mononobe equations. Accordingly, the synthetic storm hydrograph and peak discharge were estimated in HEC-HMS, the rational method, and the Nakayasu method, respectively. The resulting hydrographs were then applied in HEC-RAS to simulate water surface profiles and flood inundation extents. CHIRPS precipitation gridded satellite data were used to represent spatial and temporal rainfall variability in areas where long-term ground observations are absent. Results show that the flooded area increased from 17.64 hectares for the 2-year event to 47.44 hectares for the 100-year event, with flood depths exceeding three meters in low-lying urban areas. This indicates that terrain characteristics, rainfall intensity, and land-use changes significantly influence the magnitude and extent of flooding. The integrated model serves as a practical tool for identifying flood-prone areas and developing mitigation strategies, including floodplain zoning, drainage improvement, and riverbank restoration. Overall, this research provides a pragmatic framework for data-scarce regions to support effective flood risk management and climate-resilient urban planning in Jayapura.
Recommended Citation
Karma, Andreas, "DEVELOPMENT OF FLOOD MODELS FOR ACAI RIVER, JAYAPURA, PAPUA, USING HEC-RAS 1-D MODEL" (2025). Open Access Master's Theses. Paper 2690.
https://digitalcommons.uri.edu/theses/2690