(Written by Lu'lu Hamid)
Jogjakarta, Juni 20, 2018
When the rainy season comes, Kalimantan area faces serious problems, one of them such as flooding. A flood is the overflow of water covering the normally dry land. The very heavy rain accompanied by deforestation that occurred in central Kalimantan has caused major flooding in many of the surrounding districts. Based on Central Statistics Agency of Central Kalimantan, in the last three years, the most affected areas are Central Kalimantan. In this case, there are three main aspects related to the causes of floods in Central Kalimantan, those are global warming, deforestation for plantations and the activities of residents around the river.
The first cause is global warming, it is the rising temperatures that lead to the melting of glaciers and icebergs. This melting layer of ice results in rising sea levels resulting in flooding in some coastal areas. Central Kalimantan and all cities in the world face the potential for high floods caused by global warming. It is no stranger to us hearing the word global warming, then the impact of global warming lead to an irregular climate with long rain and cause flooding everywhere. In addition, the construction of buildings that resulted in less water absorption areas. As global warming is able to change climatic conditions, warmer air can hold more moisture than extreme or often increasing rain and intensity of the heavy rain.
The second, According to environmental activists from Friends of National Park Foundations (FNPF) Basuki Budi Santoso, the floods and landslides were also caused by ecosystems in flooded areas that change into the plantation and industrial. Deforestation in upstream areas because of the development of agriculture, plantations and housing have reduced the absorption of rainwater, trigger large water flows to the lower regions. Forests can help in absorbing excess water. Besides, forests able to help stop the flow of water. Besides, increasing human need, the trees are often cut down indiscriminately. The soil eruption also occurs because of the absence of strong trees that can hold the soil in that place. Because no one is holding back the flow of water, the river will be filled much faster so it can cause the surrounding area affected by flooding. Extreme deforestation often leads to flash floods. Meanwhile, according to Feby Nadia Putri, an English Department student of Islamic University of Indonesia, who from Central Kalimantan, she said that a lot of forests are cut down for the development of agriculture, and the most is the development of palm plantation, that is the main cause of floods in Kalimantan especially Central Kalimantan.
The third cause of floods in Central Kalimantan is the activity of residents near rivers that cause narrowing of river banks. Furthermore, also many residents who still throw waste in the river, which when the rain comes the river was overflowing because of the amount of waste.
The other case, in Samarinda city, the capital city of East Borneo, located in downstream of Mahakam River has a complex urban disaster history. In addition, flooding and forest fires are the highest frequency of disaster (Rofiq, 2015). Biophysics characteristic is vulnerable to erosion, sedimentation, and floods. These vulnerabilities are supported by types of soil are relatively sensitive to erosion, domination undulating to hilly, high rainfall and river network dominance pattern (drainage network). Floods in Samarinda is happening annually. Length, height and spacious flood that have varied, based on information obtained by Sodik (2015), the duration of the flooding that occurred ranged between 3 –10 hours with the water level between 0,3–1,5 m, while the area of inundation the contained Lempake area, with an area of inundation to ± 200 ha. Furthermore, the construction of roads, buildings, and bridges along the banks of the river also often leads to debris scattered along the banks of the river and on the river bed. The debris caused the height of river water to increase so that the river becomes more easily overflow, causing flooding in the surrounding area.
To overcome flood disaster, there are several things that we must to do to avoid the flood disaster. There are some ways to overcome flood disaster: first, creating river and sewer and make sure they work well. Rivers and sewers are where the water flows so, because of those, try not to be polluted with waste or turned into a garbage dump that eventually causes the stream and sewer to become clogged. Second, Reforestation and relocation of plants, especially with types of plants and trees that can absorb water quickly. Then, Reproduce and provide open land to create green land as a water absorption site. In addition, stop building housing on the banks of the river, because it will lead to the narrowing of the river. Besides, stop building high and sophisticated buildings that will cause the earth more difficult to withstand the burden and the resistant surface is getting down. The last one avoids illegal logging and cutting trees on the riverbank, as trees function to absorb water to prevent floods. These all ways can be done to reduce the flood disaster that often happens in Indonesia.
To sum up, to accommodate the levels of rainwater needs integrated drainage system and an increase in the size of water channels also program to dredge sediment from the city’s rivers, canals, lake, and also decrease deforestation.
Reference :
Sodik, Fajar. (2015). The City Government Efforts in Flood Control in Samarinda (Indonesia version). E-Journal of Government Science, Mulawarman University, Vol. 3 No. 2 page 782-796. Samarinda-Indonesia
Rafiq, A., Idris, Adam, Sugandi.(2015). Studies Program in Disaster Management Flood Disaster in Samarinda City On East Borneo Province’ Disaster Management Agency (Indonesia version). E-journal of Administrative Reform, Mulawarman University, Vol. 2 No. 3 page 1548-1560. Samarinda-Indonesia
