Jakarta, Ekuatorial – Coming to December, Jakarta will face floods as rain intensity is increasing. During the launch of graphic information integrating population and natural disaster on Thursday (27/11), in Jakarta, National Disaster Mitigation Agency or BNPB, pin pointed seven things from Jakarta’s floods :
Graphic Information on population and disaster risk in DKI Jakarta. Source : BNPB
Floodplain
Most of northern part of Jakarta areas are floodplains, which means they are located under sea level.
River Degradation
A total of 13 rivers from Bogor, Tangerang and Bekasi, flow through to Jakarta and end up in Jakarta Bay. But, its condition is severely degraded. For instance, Ciliwung river, located in Kampung Pulo, Kampung Melayu, Jatinegara, East Jakarta, is only ten meters wide with two meters deep. Its ideal condition was suppose to be 60 meters wide with ten meters deep. housings in river banks contributing to this condition.
Land subsidence
Land subsidence occurred in Kapuk sub district, Cengkareng district, West Jakarta. In addition, sea tide is increasing.
Low public awareness
“I found 21 bed mattresses during Kampung Pulo floods last year [in the river]. There were refigerators and chairs. The ‘do not litter’ campaign has been going on for 50 years but no changes in their attitude at all,” said head of data, information, and spokesman of BNPB, in Jakarta, on Thursday (27/11).
Land use change
The law stipulated a minimum of 30 percent green areas but Jakarta’s open space is only 11 percent left. The same condition applies to Bogor and Depok.
Lack of water catchment areas
Most of housing areas are cemented neglecting water catchment areas. As a result, puddles are regular sights during rain season. The Public Works data reported 78 flood prone areas, especially areas near Ciliwung river, Pesanggarahan river, and Angke river.
Extreme weather
Climate change is contributing to global rain patterns, including Jakarta. The changes marked by local rains with high intensity.
Based on historical record between 1879 and 2002, rain season peak in Jakarta occurred in January to February. During those times, rainfall was 400 millimeters per month, in average. Extreme rainfall, above 200 mm, only happened in one day, for instance on 5 January 1988 with 356 mm per day. However, extreme rainfalls have increased within the last decade. In Bekasi, rainfall reached to 250 mm in 2002 causing river overflown. Two years later, rainfall in Ciledug reached 340 mm per day and 235 mm per day at the Meteorology, Climatology, and Geophysics Agency monitoring station.
In 2008, floods hit Sedyatmo toll road as 317 mm per day rainfall in Cengkareng and 263 mm per day in Tangerang. Last year, rainfall in Jakarta reached 193 mm per day overwhelming Latuharhari dam and killed 48 people due to the flood.
BNPB cited Rp5 trillion (US$ 407 million) loss during February 2014 floods, spiking inflation from 1.03 percent to 1.07 percent.
Clara Rondonuwu