The potential for landslides that will trigger flash floods in the Kali river along Manado-Tomohon in North Sulawesi is still great. The floods will threaten the middle area up to the west of Manado, said researcher from Faculty of Geology of UGM, Prof. Dr. Dwikorita Karnawati, M.Sc, reporting the fact finding and analysis of the recent landslides and floods in Manado and the surroundings, Monday (20/1), at UGM Conference room.
She added the landslides and floods are natural phenomenon controlled by geological conditions such as tectonic quakes that cause slope inclinations with unstable rocks along the structure line, triggered by extreme rains and quake waves. Landslides occured in Tondano drainage basin (Minahasa regency) and Tumpaan drainage basin (Tomohon regency).
According to Dwikorita, drainage basins have the characteristics vulnerable to landslides and flash floods, especially due to nature’s control, namely inclination of the slope and geological conditions caused by high precipitations.
The fact finding showed the disasters in Manado are generally caused by the very high precipitations. On 15 January 2014 it reached 215 mm in Tondano and 41 mm/day in Tumpaan. The UGM team recommended the zone identification of areas prone to landslides and floods, disaster risk mapping and community empowerment.
“The ideal would be relocation, but if this is not possible, monitoring and early warning systems need to be developed soon,” said Dwikorita.
Chairman of UGM Community Service Institute (LPPM), Prof. Dr. Suratman, M.Sc, warned amidst the global climate change that people need to increase alertness against possible natural disasters. He pointed out the phenomenon of the rising sea surface in the North Java Sea.
“There has to be a joint research, we cannot overcome it individually. All has to be nationally tackled,” said Suratman.
As reported, landslides and flash floods hit Manado on 15 January, killing 18 people while tens of houses were buried in the landslides and thousands of home were inundated.
The LPPM has participated in disaster mitigations, involving Student Community Service and DERU (Disaster Response Unit).