La Nina, poor use of land complicate flood problems

By M.M.I Ahyani

BANDUNG (JP): Many regions in Indonesia, especially its urban centers, are suffering from the -- somewhat ironic -- problem of floods during the rainy season and a constant shortage of clean water. Experts are blaming it on poor water management and thoughtless land development.

Jakarta and surrounding areas, and nearby Bandung, are prime examples of this problem. Even one day of rain can cause flooding in these cities, while several sunny days often mean dry wells.

The latest flood to hit Bandung occurred two days before Christmas last year. At least 5,000 homes and thousands of hectares of farmland were flooded after the Citarum River and a number of streams breached their banks.

The common feature of those cities is the lack of water catchment areas due to poor land use, low absorption of ground water and saltwater intrusion, especially so in Jakarta. Proper water management to sustain the natural hydrological cycle is therefore the key to solve these problems.

In northern Bandung, for example, a huge area of land that should have functioned as a water catchment area has been turned into housing complexes.

Sri Legowo, an environment researcher and lecturer at the Bandung Institute of Technology, says that just a small amount of rain is now enough to cause floods in Bandung.

"Especially in southern Bandung, where rainwater cannot be absorbed," Legowo said, "This is proof of how bad the condition of the environment is here."

He cited poor planning and the fact that industrial and housing complexes were often developed in areas that should have been designated water catchment areas.

"It causes floods during the rain, and when it dries a bit, it's hard to find clean water," he said.

It was of course almost impossible to return the already developed areas to their original state, given the huge economic and social costs. "It would be almost impossible to tear down permanent housing complexes built on water catchment areas," Legowo said.

Floods are usually very bad in the area because Bandung lies in the bottom of a huge bowl formed by the surrounding hills, from which tributaries flow into Citarum River.

The same problem, he said, occurred in areas of Greater Jakarta, such as around the upper end of Ciliwung River in Bogor, which is already packed with buildings.

La Nina

Legowo said fears of floods were growing due to the impact of the La Nina phenomenon. La Nina, which means "little sister", arises from unusually cool temperatures in the Pacific ocean and often follows the drought-inducing El Nino weather pattern.

Early last year, experts began to issue warnings about the possibility of abnormal rains and heavy flooding across many provinces as a result of the La Nina weather phenomenon.

In recent weeks, reports of flood casualties have streamed in, with eight deaths recorded in Bengkulu and a further seven in Ujungpandang, South Sulawesi. In Bali, 40 people were buried alive in a landslide that hit Gianyar following heavy rains.

Experts have warned that 13 of Indonesia's 27 provinces were particularly vulnerable to La Nina-induced flooding. The provinces were Lampung, Riau, South Sumatra, Bengkulu, West Java, Jakarta, Central Java, East Java, Yogyakarta, Bali, West Nusa Tenggara, South Kalimantan and Central Kalimantan.

The government has admitted that established flood control projects cover less than 10 percent of areas thought to be vulnerable to flooding.

Embung

Legowo mentioned poor environmental management as a major problem, and pointed to the fact that land use in Bandung often violated zoning regulations.

Various proposals to curb the problem have emerged, including the development of embung, small dams which function as water flow controllers in order to reduce water volume downstream.

Minister of Public Works Rahmadi B.S. has welcomed the idea. Around 220 embung must be built to prevent flooding in Bandung and Greater Jakarta areas, according to Legowo.

Legowo said if embung were built in appropriate places, it would reduce by 80 percent the water flow in southern Bandung.

"Actually, an embung works with a similar principle as a dam, but it is much smaller. When the water volume is low, the water retained in it could easily be let out," Legowo explained.

The use of embung is not new, as residents of Lombok, West Nusa Tenggara, implemented it a long time ago, he said. The regencies of Central and South Lombok, which often face critical water problems, have used the system to support the kampongs' water supply when it is low.

The only problem for embung to be built is that each construction, measuring one square kilometer and with a capacity of two million cubic meters of water, will cost about Rp 2 billion. This figure does not include the cost of the land itself.

The huge waste is evident when it can be seen that by building such embung, the areas in Bandung are merely reverted to something resembling their original state, in which water flowed into small natural lakes.

In Greater Jakarta alone, the 164 original situ, or water reservoirs, were either damaged or abandoned, and some were developed into housing complexes.

According to Yusron Lubis, the coordinator of a group researching water resources at the ministry of public works, the main problem is choosing a site for the embung.

"The biggest issue is the funds needed to buy back the land. Most of the water reservoirs here, which are supposed to function as natural flood controllers, have been turned into various constructions," he said.

The problems delayed any campaign to build embung in various flood-prone areas. "Actually it is very effective in preventing floods ... a dam could last for 100 years, while embung for about 50 years," Yusron added.