Indonesian disaster report for first quarter of 2015

Jakarta Post 30 Sep 15;

There have been 600 natural disasters that happened in the first quarter in 2015. Around 97.8 percent of those disasters were landslides, floods and strong winds. In terms of frequency, landslides are most common.

Like previous years, the number of disasters that happened in January are the highest. This January, there were 285 events, most of which were landslides. While in February and March, there were 240 and 75 disaster events, most of which were caused by strong winds and landslides.

Landslides were the most deadly disasters since they resulted in many casualties or missing people. Strong winds become the most damaging disasters since they destroyed many homes.

Disasters in January 2015

The intensity of the rainy season,usually reaches its peak at the turn of the year. This January it rained almost every day. The result was it poured on most of the regions in Indonesia. Not a few of them endured floods. There were 90 cities/regencies from 25 provinces that had disastrous floods in January 2015.

Aceh province is the westernmost region in Indonesia and it was hit with floods on the second week in January. The region that has 15 watersheds is frequently struck with floods in the rainy season. In January, five cities/regencies were flooded: Southeast Aceh, Pidie, Aceh Tamiang, North Aceh and Subulussalam City.

Aceh Tamiang had the most victims, with 13,731 victims from six subdistricts. And the most flooded settlement was in Pidie Regency with at least 4,000 residencies affected.

Just like Aceh, Jakarta also become a province that was frequently having floods during the new year but the impact caused by this years’ flooding was not as bad as previous years. Not only was the rainfall in Jakarta was not as high as previous years but also many related parties had taken preventative measures. Those efforts included coordination meetings from related parties to determine flood mitigation scenarios in Jakarta. These meetings began at the end of 2014.

Combined personnel to help with flood mitigation were also prepared. The number of personnel reached more than 5,000 people, including a task force of 2,000 from DKI Jakarta’s West Maritime Fleet Command,two battalions of Marine engineers to help clean the rivers and four Kodam Jaya task forces for five regions with 1,000 people.

Besides that, the National Disaster Mitigation Agency (BNPB) also established reinforcement posts in many flood-prone points in Jakarta and surrounding areas. Those post accounted for 28 points in which 25 points were in Jakarta while two others were in Bekasi and one in Tangerang. Each post consisted of a team from BNPB along with army, military and police offices and a student regiment.

Floods also struck Banten Province in January 2015. It flooded many regions in 12 villages from Panimbang and Cikeusik subistrict, Pandeglang regency, Banten. These regions were located in flood-prone areas and have been flooded almost every year. The floods happened from the overflowed Cilember River. There were 13,054 flooded homes and 21,528 people affected.

Besides Pandeglang, Lebak regency was also struck by floods. In this region, floods were caused by the overflowing Ciliman, Cimoyan, Ciberang, Ciujung and Cibinuangen rivers and other 189 rivulets that cross the Lebak regency. The Lebak Regency Disaster Mitigation Agency (BPBD) issued an emergency alert status from December 20, 2014, until March 20, 2015. At least 5,355 people were affected and more than 2,200 houses were flooded.

The eastern part of Indonesia was also affected by the floods in the beginning of the year. Major floods happened in Manado City, North Sulawesi; Barru regency, South Sulawesi and Dompu regency, West Nusa Tenggara (NTB).

Floods in Manado happened at the dawn of January 11, 2015, caused by heavy rain that began January 10 in the afternoon and lasted until 2 a.m. local time. Because of the downpour, Tendanau River overflowed and flooded the settlements. There were seven subdistricts that were affected: Bunaken, Singkil, Paal Dua, Tikala, Wenang, Sario and Wanea. At least 2,000 houses were flooded and more than 4,000 people were forced to evacuate.

On the third week in January, floods struck Barru regency, South Sulawesi, beginning January 23, 2015. The impacted subdistricts were Barry, Tanete Rilau, Tanete Riaja, Balusu, Soppeng Riaja and Mallusetasi. There were 6,129 people that were affected in those six subdistricts.

At the end of January 2015, floods struck Dompu, West Nusa Tenggara. These floods happened because there was heavy rain and rivers overflowed. The floods affected 10 villages in Dompu and Woja subdistricts. The results, 20,000 people were affected, 4,200 house flooded, with 23 of them being heavily damaged. The flood was 4 meters high. People were evacuated to the nearest mosques, schools and other buildings that were not affected by the floods.

Disasters in February 2015

This month, most regions in Indonesia were still experiencing heavy rain. From light-to-heavy intensity, rain poured in many regions. Many regions were reportedly struck by floods, landslides and strong winds. Compared to January 2015, the number of disasters that happened declined along with the number of casualties or missing persons.

At the beginning of February, heavy rains hit Jakarta and caused many areas to be inundated by floods. Until 4 p.m. on Monday, February 9, 2015, there were 93 areas inundated in Jakarta. Those areas were scattered around, with 35 areas in Central Jakarta, 28 in West Jakarta, 17 in North Jakarta, eight in East Jakarta and five points in South Jakarta. The floods were 10-80 centimeters deep. The floods resulted in severe traffic jams in many areas.

At that time, the water level in most river systems in Jakarta reached alert III status: 80 cm at the Katulampa sluice gate (alert status III), 210 cm at the Depok sluice gate (alert status III), 820 cm at the Manggarai sluice gate (alert status III), 165 cm at the Krukut Hulu sluice gate (alert status III), 190 cm at the Pesanggrahan sluice gate, 190 cm at the Angke Hulu sluice gate (alert status III) and 675 cm at the Pulo Gadung sluice gate (alert status III). While at the Karet sluice gate, the water level reached 650 cm with alert status I. This condition resulted in many riverbanks being flooded.

Besides hydrometeorological disasters, on January 2015, there was an earthquake that happened and caused damage. The Meteorology, Climatology and Geophysics Agency (BMKG) reported a 7.1 magnitude earthquake at Friday 8:45, February 27, 2015. Its epicenter was 572 kilometers under the sea level, which was 104 kilometers northwest of East Flores or 129 km northeast of Sikka, East Nusa Tenggara. No tsunami warning was issued.

According to the map from the quake, the shock was felt in a couple of regions in northern side of East Flores with IV-V intensity (medium). The shock was also felt as medium in Sikka and Kupang. People in East Flores, Mataram City and some in Bali also felt the quake, but quite weakly. The quake that reaches 7.1 on the Richter scale is considered high intensity, however, since the epicenter was very deep, it resulted minor impact or damage. It was reported that there were 19 slightly damaged homes, one moderately damaged educational facility and one slightly damaged worship facility.

The epicenter was an active fault zone that was located on the north of Flores Island. That fault zone had an extension to the northeast of Bali that is known as the Flores back arc thrust belt. The activities from this fault zone have also caused many earthquakes that happened frequently in Sumbawa Islands and Flores. Earthquakes that happened in southern Sumbawa and its surroundings are caused by activities in the Indo-Australia subduction zone plate that is subducting the Eurasian plate. While on the north, earthquakes result from activities in the Flores back arc thrust.

Disasters in March 2015

On March 2015, landslides become the most dominating disasters. It was reported that there were landslides happening almost everyday. Most of these landslides were reported to have happened in Central Java and West Java.

Casualties and missing persons because of landslides in March 2015 totaled to 20 , 12 of whom died because of landslides that happened in Sukabumi on March 28, 2015. Previously, on March 10, 2015, there was another landslide in Sukabumi that caused three casualties. Other landslides that caused casualties and missing persons happened in Brebes, Central Java (March 12), Sumedang, West Java (March 20) and Purworejo, Central Java (March 28).

In Purworejo, landslides that happened on March 28 were also accompanied by floods. Furthermore, a sizeable flood also happened on March 16, 2015 in Indramayu, West Java. This flood affected traffic on the northern coastal highway (Pantura).

Other than that, in March 2015, an earthquake hit North Maluku. The earthquake was 6.2 on Richter scale with epicenter 10 km deep under sea bed on Wednesday, March 18, 2015, at 5:12 a.m. The epicenter was 115 km northwest of West Halmahera, North Maluku. Even though the quake did not triggered any tsunami, the effect was shocking to people in West Halmahera. The cause of the quake was activity in fault zone and a shifting plate resulting from a fault under Maluku sea.

The earthquake lasted for five seconds. People of Ternate also felt a strong shock for three to five seconds. Even in Manado, people could feel the shocks. People that were used to earthquakes were not in panic. Some of them responded by walking out of their houses. From a report that was received from the BNPB, there were 11 heavily damaged homes, 10 moderately damaged homes and 15 slightly damaged homes.