PERENCANAAN NORMALISASI SUNGAI HATU HILIR PADA DESA HATU KECAMATAN LEIHITU KABUPATEN MALUKU TENGAH

River is a natural drainage which has a function to channel excess rain water from a higher place to lower place and ends to the sea. Hatu River is one of the major rivers located in Ambon island, precisely at Hatu Village of Central Maluku regency. The river is unique since its capacities in several segments are too narrow and the river basin is not a Streamline-type. It reduced the drainage capacity of the rivers which then it causes yearly flood and waterlogging. Therefore, it needs to conduct a special study to obtain the best handling solutions to overcome the existing problems. The research was conducted by using both hydrology and hydraulics analyses. Hydrological analysis was performed to determine the maximum flood discharge with periodical flood. Hydraulics analysis was performed by using the HEC-RAS software package to determine the maximum water level of the flood in various forms of river geometry. The simulated results by using HEC-RAS software showed that water level of the occurred flood when the discharge (Q) existed with its periodical 10 years was 299.97 m3/s that coinciding with maximum tides, and also it produced a runoff of 2.32 m height at RS 16. Therefore, it was reasonable to build the dikes. Decreasing the water level can only be done through normalization effort at the river section. While the water level for both geometry conditions e.g., jetty and jetty+dredging, was not affected significantly