National Capital Integrated Coastal Development (NCICD) – Phase 2

Context

The coastal zone of Jakarta has been sinking for many decades. Land subsidence rates are between an few centimetres per year up to 15 centimetres per year. Coastal areas which were still above sea level one hundred years ago have sunk to 3 meters below sea level. More and more land is situated below sea level and existing sea walls need to be upgraded every five to ten years to stop sea water entering the city. Groundwater extraction for water supply is an important factor in the sinking and the city administration is working hard to replace groundwater extraction with other forms of water of water supply. Nevertheless, the city will continue to sink, albeit at a slower pace.

The existing sea wall is around 120 kilometers long and is integrated in the residential, commercial and industrial areas. This creates a difficult urban setting for upgrading the sea defenses as houses, factories and other infrastructure are to be removed from the sites. Upgrading will become more and more difficult over time and the need for a new protection strategy is becoming clear. In the coming 10 years the existing long, complicated urban sea wall could be replaced by a shorter (25 to 30 kilometers) offshore sea wall, which would simplify the sea defense. This concept is similar to the Dutch "Afsluitdijk" or "Deltawerken", which are based on the same concept.

The Jakarta Coastal Defence Strategy (JCDS 2008-2011) and the National Capital Integrated Coastal Development (NCICD I 2012-2015 and NCICD II 2016-2020) projects aimed to provide a short, medium and long term strategy. Both JCDS and NCICD stressed the importance of managing the land subsidence, improving the water quality in the rivers and canals and a revitalization of the coastal communities (thus the words 'Integrated' and 'Development' in NCICD) as important contributing factors.

Approach

Summarized, the protection strategy would consist of three phases: upgrading the existing sea wall would buy some time and this upgrade should be completed in the short term. At the same time, providing alternatives for ground water extraction and improving water quality should be given priority. For the medium term an offshore breakwater (open dam) should be constructed, including a toll road (to relieve the coastal road network). The open dam aims to keep storm waves away from the coastal dikes, while allowing for a water flow through the reservoir behind the breakwater (to keep water quality acceptable). In the long term, this open breakwater may be closed and water levels behind the closed dam may be lowered to allow for lower flood protection works in the coastal area. As the water behind the closed dam will be fresh water from rivers and canals, this reservoir may be used for water supply, provided that the water quality in the rivers and canals has improved.

An important condition from the government of Indonesia was that all the works should be financed by private investors. The main source of income would be land reclamations in the Bay of Jakarta. Several options for these reclamations have been developed over time, ranging from large scale, iconic reclamations (the Great Garuda 2014) to sober, minimal reclamations (IFSP 2020).

Involved partners and local parties

Over the years many parties (from Indonesia, Korea and the Netherlands, both private and public) have been involved.

The JCDS and NCICD projects were undertaken under a MoU Water between the Governments of the Netherlands and Indonesia. In NCICD II, also the Republic of Korea joined the cooperation and the NCICD II project was executed under a three-party MoU. The Indonesian counterparts were: the Indonesian Ministry of Public Works and Housing, the coordinating Ministry of Economic Affairs and the National Planning Ministry BAPPENAS. The special province of Jakarta (the city) was deeply involved in JCDS and NCICD I, but opted for a more distant role in NCICD II. The Indonesian government was supported by Indonesia research institutes and universities.

Key consultants were: Witteveen+Bos (managing the NCICD projects, integrator), RoyalHaskoningDHV (technical and institutional aspects), SWECO (strategy, environmental and social aspects), Deltares (hydraulical analysis, capacity building), RebelGroup (financial analysis), Ecorys (cost-benefit analysis), KuiperCompagnons (urban planning Great Garuda concept in NCICD I), Triple-A consultants (NCICD: urban integration, JCDS strategy), Bita Bina Semesta (social and environmental assessments).

Key outcomes

The three-step, integrated flood safety and development strategy (detailed in the Integrated Flood Strategy Plan 2020) is the main outcome of this project. Next to this strategy, more detailed plans and designs were made for the short term (so-called Stage A) which are currently being constructed.

Uptake/follow-up

The current sea defence is currently being upgraded, based on the NCICD project. In several locations, mini-land reclamations are being added to allow for urban upgrade of coastal communities.

Media library

NCICD2-standaard

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