Technology Orientation Overcome Jakarta Flood

Technology Orientation Overcome Jakarta Flood

After the hole biopori, another one researcher's findings technologies Bogor. Agricultural Institute (IPB) to address the problem of runoff and flooding in Jakarta. The technology is called orientation. Orientation basic principle of retaining water in the area to fill aquifer is free, so the water can be controlled and utilized optimally for the benefit of society. The system combines orientation between wells with plants.

" The orientation is applied technology that combines elements of plants, 'green water' and 'blue water' in a landscape with a maximum water soak into the ground. The water can be harnessed for the benefit of the community," said Specialist Field Hydrology and Ecosystem Watershed (DAS) Faculty of Forestry, Ir.Nana M.Arifjaya at Press Conference, Tuesday (17 / 3) at the Campus IPB Darmaga.

"Green water" is water stored in trees and land, while the "blue water" is water being stored in the form of springs, rivers and lakes. According to Nana, approximately 44.91 percent or 28,902 hectares of land in Jakarta is able to absorb water well. "That said, this area becomes a giant sponge that is ready to store water. The problem, land area is already covered buildings and asphalt."

With average rainfall in Jakarta 2000 milli meters per year, on land utilization orientation technology is capable of storing 578.34 million cubic meters of water per year or 1.6 million cubic meters per day. 

This amount is sufficient to meet the domestic needs of about 7.9 million urban communities.

"With the distance of 2 to 3 feet from the well orientation, the residents could put a water pump, so that they no longer need running water," said Nana. Making orientation can be done in the yard, gutters, sidewalks, parks, parking lots, narrow alleys and densely populated. No need to land acquisition, and does not eliminate the land area.

Manufacturing process is fairly simple. First, making a small ditch to the wells. Second, digging wells one square meter depth of 2.7 meters. Thirdly, the installation of retaining walls anesthetic infiltration wells. Stunning prints made of concrete, shaped like a rectangular window measuring one meter, and has four holes.Stunning mounted on the left and upper right side under the wall of wells. Fourth, the installation of palm fiber and stone in the wall below infiltration wells as deep as 1.7 meters. Fibers and stone serves to absorb water and resist the kinetic energy of water into the bottom of the well. Fifth, the installation of the well cover. This cover is made of concrete.

Rain water runoff deliberately directed into the well through a pipe, so water does not all flow directly into the lower regions. In 2008, the team has made IPB orientation wells at 800 locations in Jakarta. This year, 100 wells planned to be made again. Areas that allow for the manufacture of these wells are mostly located in East Jakarta, West and South.

In the calculation IPB team, the ideal number for the entire watershed orientation wells in the Greater Jakarta area is 261,622 units with the ability to absorb rainwater 437.2 cubic meters per second. 123 706 units of which are made in Jakarta and 6642 units in the city of Bogor.

Funds to make one well orientation approximately USD 2.5 million.Costs include excavation, soil disposal, manufacture and installation of wells. To make more than 261 thousand wells in the Greater Jakarta orientation needed funds around Rp1 trillion, far lower than the cost of construction of the east flood canal that reached Rp13 trillion.

Orientation different wells in general. Some factors to consider in making orientation include ground water depths of more than 3 meters, the land selected is not saturated water, is a land built (building up), instead of alluvial soil (silt sediment), the distance from the septic tank is more than 8 meters, geological location of the land selected aluvail fan who has such a high absorption foam."The cause of the failure of production wells due to its manufacture does not take into consideration the geological land, without planning and supervision of mature," said Nana.

Flood control is more perfect if the dams are also built dams to control and restraint at some point along the rivers. This dam serves to reduce the speed of water flow from upstream to downstream, especially during heavy rains or high water discharge. "Special Ciliwung control dams needed 298 units and 66 units of the retaining dam," said Nana. (Ris)