Dam development in Indonesia14 September 2021
Members of the Indonesia National Committee on Large Dams give an overview of recent activity across the country’s dam industry
The recent rapid development of dam construction in Indonesia started in 2014 when the government declared it would build 61 new dams in the first five years, plus an additional 12 dams until 2024. This number only reflects those projects under the Ministry of Public Works and Housing (MPWH) and excludes other dams belonging to the private sector or state-owned companies.
The government also launched the Dam Operation Improvement and Safety Programme (DOISP) which will look at 140 existing dams until 2023 and includes remedial works if required after detailed evaluation.
In this article we will look at the Ministry of Public Works and Housing’s Jatigede Dam and the Martabe Tailing Dam built by a private investor. Although the two large dams are of different purposes, they are both currently dams of more than 100m in height. All new dams are built in compliance with National and International standards, including ICOLD bulletins, because Indonesia always maintains its role as an active member of ICOLD globally and also regionally in the Asia Pacific Chapter.
Downstream view of Jatigede Dam
Jatigede Dam is located in the Jatigede village, Sumedang District in the West Java Province about 200 km from Jakarta, the capital of Indonesia. The idea behind construction of Jatigede Dam was started in 1960. Initially, the development was initiated by the Dutch government after road construction Cadas Pangeran in 1913. Detailed design was prepared in 1986 by consultants SMEC Australia and was reviewed by a joint operation of national consultants PT Indra Karya and Wiratman and Associates. The design received approval from IDSC under the Ministry of Public Works in February 2006 after the completion of a lengthy process of land acquisition. Soon after that, the construction started with a special focus on the geological conditions.
The dam has a rockfill clay core and is 114m high from the bottom of the foundation at El. +265 m. The crest dam is 1715m long and 12m width. The slope at the upstream is 1V:2.0H and downstream 1V:1.9H. It is equipped with a grouting gallery (3m wide x 3.5m high) which is located under the core with 532m length on the left side and 145m on the right side. Storage capacity at maximum water level (MWL) El. +262 m is 1061 MCM with an inundation area of 41.22 ha, while the effective reservoir (El. +230 ~ El. +260 m) is 796 MCM with an inundation area of 39.52 ha.
The purposes of Jatigede Dam are mainly for:
- Providing water supply for irrigation with the service area of more than 90,000 ha.
- Providing domestic drinking water supply for the Cirebon and Indramayu Regencies of 3,500 l/s.
- Hydropower of 2 x 55 MW.
- Controlling flood from Cimanuk river around of 14,000 hectares.
- Supporting local tourism and fishery.
The reservoir impounding was done in August 2015. The power house of Jatigede Dam has already recently finished and it is ready to supply electricity around Java Island.
Martabe tailings dam
Martabe tailings dam
Martabe tailings dam is located approximately 40 km southeast of Sibolga, in North Sumatra, Indonesia where the seismic activities are recorded quite high near the centre of major active faults. The dam is developed, owned and operated by PT Agincourt Resources (PTAR) which focuses on gold mining. Martabe dam will store slurry tailings from processing the ore, with solids contents around 40-45%.
The original dam design was designed to provide approximately 25Mt (35Mm3) of capacity to a crest elevation of RL 330m. The dam was raised right now until RL 360m and capacity will be approximately 56Mt (78Mm3) of tailings. Right now, the crest will be increased to final elevation to RL 377 m, with crest width 10m, to produced storage capacity 87Mt (121 Mm3). PTAR was commissioned to provide design, construction services and technical support pertaining to ongoing development of the dam and expansion to a final crest elevation of RL 377 m.
The dam is a rockfill with inclined clay core, approximately 112mr high (RL 377 m) from deepest foundation with three phases of heightening, with an overall status of the highest tailings dam in Indonesia. The crest dam length is 800m, with width 10m. Upstream slope is 1V:2H and overall downstream slope 1V: 3.3H (1V:2.8H with 5m benches every 10m vertical height). Stringent monitoring on dam performance is continuously conducted by PTAR from the starter dam up to the current crest level and is reported regularly to the Indonesia Dam Safety Commission and the Indonesia Dam Safety Unit.
Dam construction, operation, maintenance and rehabilitation in Indonesia have been intensively implemented as illustrated in the two examples above. In addition, quite a number of dams are being built for the specific purpose of hydropower generation by the State of Electricity Company (PLN) and the private sector in line with government programmes to promote more renewable energy projects and reduce dependency on fossil fuel-based power plants.
The combination of a hydropower (1008MW) and solar power (145MWp) project also started near the Cirata Dam in early 2021 by adding floating photo voltaic on a dam reservoir, with a commercial operation date in late 2022.
In other locations the government is also building dry dams to reduce flooding in major cities, including Jakarta as the National Capital City. These activities require serious attention from Indonesian engineers to secure the achievement of targets for reliable, sustainable and most importantly safe dams for the benefit of all communities in the country with over 260 million of population in an archipelago with around 17,000 islands. The potential of dam development in Indonesia is promising to support its economic growth and welfare of the whole nation.
Aries Firman, graduate Civil Engineer in 1977 from Bandung Institute of Technology (Indonesia) and PhD in 2005 from Curtin University of Technology (Australia). He started activity in dam projects with a construction company in 1981 and has continuously being involved up to now as a member of the Indonesia Dam Safety Commission under Ministry of Public Works and Housing. He has served on the Indonesia National Committee on Large Dams (INACOLD) since 1986 and currently is the Vice Chairman. Aries is now a member of a Technical Committee of ICOLD as well as a member of International Scientific Committee of ICOLD Symposium 2021 in Marseille.
Duki Malindo, graduate Civil Engineer in 1999 from Trisakti University (Indonesia) and Master Degree in 2001 from University of NSW, Sydney, Australia. He has been involved in several dam projects since 1996 and has a professional certification from the Indonesian National Committee on Large Dam (INACOLD) as a Senior Professional Dam Engineer. Currently, he serves as the Secretary General of INACOLD and Head of Indonesia Dam Safety Unit.
Anissa Mayangsari, graduate Environmental Engineer in 2004 from Bandung Institute of Technology (Indonesia) and Master Degree. in Bandung Institute of Technology (Indonesia). She started her professional career at the Dam Safety Unit in 2006 as technical staff and is also getting involved with dam safety analysis and design approval in Indonesia. Anissa is also a member of INACOLD.
Tri Hartanto, Geologist, graduate from Padjadjaran University, Faculty of Mathematics and Natural Science, Bandung, Indonesia. Master candidate in Geotechnical Engineering from University of Indonesia. He has been working in the Indonesia Dam Safety Unit until recently and is a member of INACOLD.