Adianto P. Simamora, The Jakarta Post, Jakarta
Due to a disruption in clean water supply, a number of industrial players and high-rise managements in Jakarta have applied for permits from the Jakarta Mining Agency to dig deeper into the ground to obtain fresh water supply, an official said Tuesday.
Dian Wiwekowati, the head of the agency's groundwater monitoring unit, said the applicants already had permits to exploit resources for their primary water needs but wanted to dig deeper wells because their wells were not longer providing a reliable and ample water supply.
""We have received letters from several industrial players requesting permits to dig deeper,"" Dian said.
The industrial estates and the high-rise managements get the allocated quota of 100 cubic meters per day from their groundwater supply.
The groundwater wells -- explored and maintained by respective estates and high-rise managements -- are intended to be an alternative to the supply from city water company PD PAM Jaya.
Currently, 3,655 companies have groundwater permits.
The depth of wells is limited to between 100 and 300 meters, with preserving groundwater supply cited as the reason for the regulation.
""The limitations on both the depth of the well and the volume of water were set to protect the city from further land subsidence,"" Dian said.
The agency earlier said that 80 percent of the city's land subsidence was due to the construction of buildings, 17 percent to groundwater exploitation and 3 percent to natural causes.
Despite official checks, the agency suspects that many companies in Jakarta illegally tap groundwater.
In addition, half of the city's inhabitants continue to rely on the already-polluted groundwater at a depth of less than 40 meters.
However, because of the poor quality of the groundwater, many residents use it only for bathing or washing clothes, spending extra money on bottled water for cooking or drinking.
The agency said that in low-lying North Jakarta, groundwater depletion had caused serious land subsidence making the area more vulnerable to flooding.
Jakarta, 40 percent of which is located below sea level, has long experienced water shortages in the dry season and floods in the rainy season.
Experts have warned that the recent heat wave in the city could signal the return of water shortages.
Dian said the groundwater supply in the city had continued to decrease, partly due to the increased rate of runoff.
The agency has estimated that of the average two billion cubic meters of rainfall in Jakarta each year, only 170 million cubic meters is absorbed into the ground.
The high volume of runoff results from the dwindling number of water catchments in the city.
In 2005, the administration issued a decree on water conservation requiring the owners of houses, hotels, apartments, private and state offices and shopping malls to build water reservoirs to catch water from rainfall.
The decree stipulates that for every houses with 50 square meters of roof width, the owners are required to construct a water tank holding 2,000 liters, while developers who build buildings with 5,000 square meters of roof width or more must set aside 1 percent of that total area for a water catchment facility.
However, at present there are only 13,579 units of catchment wells in the city, lower than the minimum of two million wells required to catch the rainwater.
The city administration is currently drafting a bylaw on water to seek alternative ways to produce clean water by promoting high-tech devices such as machines for turning seawater into potable water.
