Determination Of Subang Groundwater Basin Recharge Area Zoning Are There In The District Of Subang West Java Province

Abstract

The intensity of groundwater extraction, each year has increased along the
various factors that contribute to it. Therefore, the management of the utilization of
groundwater resources is an important step in the effort to preserve and maintain
the sustainability of the potential of groundwater in the basin in Indonesia, one of
which is the Subang Groundwater Basin in Subang district.
The study was conducted to determine the hydrogeological conditions, by
examining the wells (boreholes and wells) around Subang Groundwater Basin, and
determine the zoning of recharge area in Subang Groundwater Basin, with
reference to the book Kumpulan Panduan Teknis Pengelolaan Airtanah (PLG,
2007), namely by scoring.
From the results of correlation some drill logs, it in found out that in the
Subang Groundwater Basin area there are 2 aquifer systems, that is : unconfined
aquifer system and semiconfined aquifer system. Data from wells in the unconfined
groundwater level flow map, and the map of the known direction of groundwater flow
in Subang Groundwater Basin, from the direction of the southern part to the northern
part of Subang Groundwater Basin. Likewise with more catchment areas located in
the south of Subang Groundwater Basin than central and northern regions of
Subang Groundwater Basin.
Determination of Subang Groundwater Basin (Anonymous, 2007), based on:
1) passing the rock; 2) rainfall; 3) soil cover; 4) slope; 5) unconfined aquifer flow.
Each parameter has a ranking value from 1 to 5. The ranking value assessment is
carried out by making a grid of 2.5 cm x 2.5 cm on the Subang Groundwater Basin
map, then each grid is ranking value according to the circumstances of each
parameter. Then the ranking value of each grid of each parameter included in the
recharge value formula.
Then the results are colored in accordance with the provisions. From the
map classification (Zoning) it could be concluded that in the southern and central
part of Subang Groundwater Basin categorized in the Main Recharge Area, and in
the northern part of Subang Groundwater Basin categorized in the Additional
Recharge Area.