Adianto P. Simamora, The Jakarta Post, Jakarta
To anticipate clean water shortages, now a key issue in the city both during the dry and rainy seasons, the Jakarta administration plans to make the establishment of retaining ponds mandatory.
The plan is stated in the draft of a gubernatorial decree that will require the operators of commercial areas or housing developers to build rainwater collection reservoirs.
Jakarta Mining Agency head Penny Susanti said the ponds would be alternative sources of clean water, reducing dependency on groundwater.
""Building retaining ponds will be mandatory in the development of residential, commercial and industrial areas, and in similar projects, because the residents or tenants of the premises are the main consumers of groundwater,"" she told The Jakarta Post on Tuesday.
She said the decree was expected to take effect this year, prior to the start of the rainy season.
Penny said the decree would affect both new and old commercial and residential areas alike.
""The operators of the existing commercial areas may set up the reservoirs outside the complex, with their size calculated in accordance with the size of the property,"" she said.
The 2005 gubernatorial decree on water conservation requires the owners of houses, high-rise hotels, apartments, private and state offices and shopping malls to build rainwater collection reservoirs.
For every 50 square meters of roof, the owners are required to construct a 2,000 liter pond. While developers with 5,000 square meters of roof area or more must set aside 1 percent of that total area for a retaining pond.
Calls to build more reservoirs came as the waters receded in the flood-stricken city early this week.
Vice President Jusuf Kalla said the capital needed to build more retaining ponds to prevent flooding in the future.
He said the Presidential Palace and ministry offices would not be excluded from the campaign.
However, Iman Sudjono, the head of the conservation unit of the city mining agency, said the retaining ponds would not be suitable for all areas of the city.
""They may fail to work in low-lying areas such as North Jakarta.""
However, Iman added, his office planned to accelerate the construction of reservoirs and rehabilitate lakes to increase the rate of water absorption and storage.
There are currently 106,873 retaining ponds in the city, of which 1,090 units were built by the agency using budgetary funds.
The agency plans to build 100 retaining ponds this year.
Jakarta has long experienced water shortages in the dry season and floods in the rainy season.
Half of the city's inhabitants rely on groundwater.
Residents are not required to obtain permits for pumping groundwater, though industries are. Business players are only allowed to pump the water from depths of between 100 and 300 meters.
The mining agency has issued 3,655 groundwater permits to date.
