T

he long history of floods in Jakarta has been recorded since the early 19th century. The Dutch East Indies had established some facilities to reduce inundation areas near the city center. A prominent effort was the Kanal Banjir Barat (West Floodway). This facility was built to overcome increasing flood discharge due to massive tea plantations in the upstream area, especially Puncak in West Java. Other facilities such as revetments, small ponds and floodgates were also installed around the city.

Basic policies for flood countermeasures were implemented based on several studies. In 1973, the Netherlands Engineering Consultant (NEDECO) published the first master plan to overcome Jakarta flooding as a part of a project under the public works ministry. Since then, following studies have also suggested various solutions to Jakarta floods, including the “National Capital Integrated Coastal Development Study 2013-2014”.

From those studies, increasing capacity of the Ciliwung River to 500 cubic meters per second, equal to 50 years of flood cycles probability, has been raised as the main solution for Jakarta floods. In the upstream side, construction of the Ciawi and Sukamahi dams are still ongoing in West Java. However, instead of discussing possible solutions to Jakarta floods, nowadays, the public seem to be confused by terms of normalisasi (normalization) and naturalisasi (naturalization).

Recently, normalisasi has been used to describe the work of increasing a river’s capacity and the construction of revetments along the river channel. But Jakarta Governor Anies Baswedan has introduced the term naturalisasi, purportedly to make river works seem more nature-friendly, to meet the ecological function and purpose of the river to drain the water when a flood comes.

Preservation of Ciliwung’s environment largely involves several NGOs. Their work is mainly to clean the river, plant trees and try to restore some parts of Ciliwung. But their works are limited to locations in certain districts, not the entire length of the river.

Indeed the 145-kilometer-long river from the upstream to downhill is much larger than the capabilities of local communities. The government should pay more attention to these communities and work with them to make a more significant impact. In the old days, the clean river initiative Prokasih (kasih also meaning love) was among the popular government programs to reduce garbage in and around rivers.

Some residents living around the river have also criticized the normalisasi of Ciliwung, which involves concrete structures that significantly reduce the integration between water, river banks and the surrounding riparian area. While critics are correct from an environmental point of view, from an engineering perspective, revetment with concrete sheet piles for some parts of the river with unstable soil conditions may be necessary.

Lack of communication and incomprehensive dissemination of detail plans to the communities causes different impressions. Some locals fear all concrete revetment and concrete sheet pile will be constructed all along the Ciliwung.

In the past decades, a new approach in river engineering has given more chances to river communities to offer their ideas on river restoration and improvement plans. One example is using bioengineering material for riverbank protection instead of concrete.

The communities could help plant the material, such as akar wangi (vetiver plants) or bamboo trees along the river, and they can tend to them periodically. Another example is applying rubble or rip rap as an alternative for the inner bank of the riverbend in place of sheet piles. This could also be combined with bioengineering material. However, concrete sheet piles might still be necessary, especially for riverbanks close to a main road or highway.

River restoration projects could be further introduced by the government to promote Ciliwung as a historical site of Jakarta. Communities also need to be involved to increase public participation. River restoration could be easier, since the communities already have their own region or their own river segments. One of those regions could be selected as a pilot project for river restoration, which would promote people’s desire for a better river environment for the Ciliwung River.

From such activities, the terms normalisasi and naturalisasi should not be contrasted against each other. They could be combined based on new approaches to river engineering.

What’s most important is involving the community as much as possible to maintain the project’s sustainability. Governments may change, along with their changing policies that sometimes confuse the public. But the spirit to turn the river into a space that can maintain its ecological function, such as a good habitat for river creatures, must remain the focus of all policies and projects, including flood prevention and mitigation.
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