In last January, there were some floods happening everywhere in this country, such as in Jakarta, Tangerang, Subang, and the North Coast (Pantura) areas including Cirebon, Pemalang, Batang Pekalongan, Jepara and Pati. Major flood also happened in Manado. Obviously, the victims suffered a lot of losses, both material and psychological loses and even fatalities. We feel sorry for the disasters and hope that the floods will subside.
Floods can be caused by many factors such as heavy rainfall, silting of rivers, sea water abrasion, changes in land use in the upstream areas, lack of green spaces in urban areas, and lifestyle of the people who are not environmentally friendly. Of those various factors, we have to evaluate what caused the recent floods, such as the flood that happened in Jakarta. Floods in Jakarta are caused by land conversion in the upstream regions. According to WALHI, floods and landslides occur due to forest conversions. The deforestation is done for residential and industrial needs. The diminishing forest areas in the upstream areas finally cause floods. In addition, the availability of green open space in a city or a region also affects the occurrence of floods. The green open space serves as the rainwater catchment area. If the space does not meet the standards (30% of the total are of the city or region), the environmental supports will not work well, which can increase the number of flooding.
One of the concrete steps we can do to prevent floods is to give more space for the forests. Forests have an important role in the water function such as:
The number of layers of porous humus and roots optimize the function of the forest as a water catchment area. The absence of this catchment area can lead to scarcity of clean and hygienic water.
The density of plants and the average height of a tree in the forest are useful to protect the soil surface from pouring rain. Without the trees, loose land that receives high rainfall will gradually be eroded, which will increase the susceptibility to landslides in the surrounding areas.
If a region has a forest, the rainfalls will be absorbed by the soil. If the forest is converted into a watertight land, such as housing, the rainfalls will not be absorbed and will flow directly into surface streams. This will increase the potential for flooding in the surrounding areas, especially those with the lower height.
The ignorance about the existence of forest results in the frequent flooding in Jakarta. Many water catchment areas around Jakarta have been changed into real estate, office complex or apartment, and a magnificent shopping center. The water catchments in the upper areas like Puncak, Cipayung, Bogor, and Depok have also been converted. The ground hardening due to the establishment of the office buildings and the residential complex in the areas that were once mountain forests contributed greatly upon the occurrence of flooding in Jakarta. Without water catchment and retention areas, there is an imbalance of input and output system of groundwater in Jakarta and surrounding areas. Due to that imbalance, the heavy rainfalls will flow directly to the stream and overflows the rivers in certain areas before eventually ending in the sea.
Moreover, the area of the city has very few green open spaces (urban forests and parks). Jakarta only has 9 urban forests, namely Angke-Pluit, Kemayoran, Srengseng, Halim PK, Cilangkap, Ragunan, Setu Babakan, Cibubur and University of Indonesia. Those 9 urban forests are insufficient as rainfall catchment area, even if coupled with the landscaped garden in residential areas.
The same thing happens in Bogor as the upstreams of Ciliwung and Cisadane rivers. Bogor only has Kebun Raya Bogor, Research Forest located in Darmaga, and Forest Research Institute in Gunung Batu. In Ciawi until Puncak, the existence of protected forests and conservation forest has been increasingly displaced by the existence of villas and hotels. Data from Forestwatch Indonesia shows that there is shrinking forest covering an area of 4,895 hectares during 2000-2009.
To cope with the alarming condition, the government of Jakarta and Bogor take concrete steps to dismantle hundreds of illegal villas and hotels in Puncak area to be reforested. This step is expected to restore the function of the upstream areas as rainwater catchment area.
For those of you who want to participate in restoring forest in Indonesia, Harfam provide opportunities for you with its incredible concept. Through the Teak Afforestation Partnership, Harfam brings the concept of People, Planet, Profit which gives the advantage not only for you but also for many parties including the environment and the surrounding communities.
Harfam develops teak forests on unproductive lands in area Bondowoso and Situbondo. The forests are very useful as a rainwater catchment area. In addition, the surrounding community also benefit from the employment. And of course, this forest will give economic benefits for you with the potential profits of up to 15 billion/hectare.