City asked to anticipate floods by dredging rivers
Bambang Nurbianto, The Jakarta Post, Jakarta
The Meteorological and Geophysical Agency (BMG) said rainfall during the next rainy season would be normal, but that should not be regarded as a guarantee that significant flooding would not affect the city, given its lack of flood-prevention infrastructure.
BMG's head of forecasting and services Achmad Zakir therefore urged the city administration to anticipate possible flooding by dredging all rivers that could potentially disrupt the flow of rainwater in the city and from upland areas of the city.
"Heavy downpours are only one of the elements that can cause flooding. Another is the city's flood-prevention infrastructure. So far I have not seen a significant move to improve the infrastructure," Achmad told The Jakarta Post on Monday.
"Although rainfall in the city will not be as heavy as last year's, the necessary measures should begin now. Heavy rainfall in the Bogor area, which is unpredictable, should be anticipated," Achmad said.
BMG does not include Bogor regency, West Java, in the seasonal forecasting region (DPM) as rainfall in the area is unpredictable.
Achmad said that, based on the BMG forecast, the rainy season in the capital would begin in early October. Rain would start to fall in the southern part of the city, while other parts would receive rain in November.
He added that the peak of the rainy season would occur in January next year. He estimated that the downpours in Jakarta and its surrounding area for the next rainy season would be normal: between 977 millimeters and 2,360 milimeters.
Achmad, however, said that in Jakarta and its environs late September was a transitional period between the dry and rainy seasons; therefore sporadic rains had already begun in several areas.
Meanwhile, Mezak A. Ratag, head of climatic affairs at the National Aeronautics and Space Agency (Lapan), said that rainfall in Jakarta and surrounding areas could be higher than normal.
"There is a possibility that rainfall in Jakarta and other parts of Java could be 15 percent to 20 percent higher than usual if the warm water storms head to the Indian Ocean," Mezak told the Post on Monday.
He said Lapan was currently studying developments concerning the storm, the results of which were expected to be known next month.
Meanwhile, head of the Public Works Agency (PU) IGKG Suena said that the city administration and the central government had begun to make some improvements to the flooding infrastructure, including dredging a number of rivers and repairing the city's drainage system.
He said that the central government had allocated Rp 70 billion to dredge a number of rivers, including Kali Angke (for three kilometers), the Ciliwung at Jl. Gunung Sahari and several other smaller rivers in the city, which were silted up.
The city administration has allocated some Rp 3.5 billion for improvements to the drainage system.
"The projects are being carried out now and are expected to be completed in December," he said.
Suena, however, said there was no guarantee that flooding would be totally under control as the main flood project, the Eastern Flood Canal, could not be implemented this year.