Learning from Nanggroe Aceh Darussalam Some Notes on Post-Tsunami Rehabilitation in Calang, Aceh Jaya Dr. Widjaja Martokusumo School of Architecture, Planning and Policy Development Institut Teknologi Bandung (ITB) International Symposium on Restoration and Development of Tsunami Affected Areas in Indonesia at the University of Applied Sciences Erfurt, Germany, January 30-31, 31, 2007.
N Damage Assessment Approach (After pre-survey) Destroyed Shoreline/Town Banda Aceh RING 1 Flooded Areas RING 1 Flooded Areas Flooded Areas 3.3km Grand Mosque Flooded Extensive RING 2 RING 2 Areas Amounts Of Debris/Damage RING 3 Quick Bird Natural Color Image 28 December 2004 RING 3
Ulee Lhee Before After
Meulaboh
Earthquake-generated tsunami Nanggroe Aceh Darussalam (Aceh) was hit by earthquake generated tsunami in December 26, 2004 (2 years later the last earthquake e in Taiwan, a December 26, 2006 with 7,1 Ms at 20.26 local time) Casualties more than 200.000 people Physical damages and psychological l shock The long-drawn-out post-tsunami tsunami handling, ranging g from cleaning up the ruins, debris and corpses, providing water and food supply until temporary shelter, triggers increasing of diseases
The Coastal Town Calang Calang, a coastal town at West Aceh, mostly a flat area (slope less than 15%) known for its fishery and marine tourism The total length of road area was 139 km Surrounded with 20-30 m hills, but daily activities and routines take place along the coastal area close to the sea (10-15 15 m), Figure 1: The coastal town Calang, Nanggroe Aceh Darussalam Source: (Darmoyono/Har/Octaviana, 2005) Centre of economic activities of the region Aceh Jaya
Calang, Aceh Jaya Before After
Calang, Aceh Jaya About 70-80% Aceh Jaya s coastal area with the height below 25 m suffers a total destruction. The horizontal inundation distance is measured up to 2-4 km from shore line. Five villages with their 3205 inhabitants were destroyed. d According to collected data (2004), the town of Calang a have 11,000-14,000 14,000 citizens, and 70% of them due to tsunami disaster have been reported died
Calang, Aceh Jaya A small island near Calang, Aceh Jaya, which was used to be part of the main land, this picture was taken after the tsunami disaster
Destruction zones Zones 1 (Shore area, 7 m altitude and 0-2% slope) Zones 2: (7-12 m altitude and 0-8% slope) Zones 3 (above 12 m altitude and 0-8% slope) All fishermen houses are completely dissapeared Flooded area Salty under-ground water Watery ground Unstable ground Structural damage Infrastructures & Public Buildings, not only destroyed, but also swept away by Tsunami Minor destruction area
Settlement Relocation Alt 1 Existing condition (Easy washed-up by Tsunami because too close to coast) Extremed proposing condition by transfering city to deep village (note that the citizen must be voluntary relocate) City Relocation Moderate proposing condition, with anticipative used-order area for Alt 2 disaster. Living zones are placed away from coastal-line. Shore Zone Buffer Zone Civic Zone Commercial Zone Living Zone
Based on Calang Spatial Planning (RUTRK) by National Development Planning (BAPPENAS) and Public Works Departments, Calang is divided into 9 different zones to keep the city most activities at remote distance from the sea. The fishermen kampong located 1 km off-shore. The area of 300-400 m from coast- line is planned for mangrove forest, and the next 500-700 m is dedicated as a tourism area
Facts Those concepts are considered ideal, and surely they do not fit to the socio-cultural cultural context. Only a week after Tsunami some local fishermen have already rebuilt their houses next to the shore line without waiting for any formal master plan. Just like the nature of fishermen s tradition, their settlement can not be separated from the shore line/sea. The question is, how far should be the distance from the shore line?
Seven Principles of Design for Tsunami Resistant According to National Tsunami Hazard Mitigation Program (NTHMP, 2001), there are seven principles in designing built-up up environment for tsunami resistant: Understanding the risk of tsunami Avoid new development in tsunami run-up up areas to minimize future tsunami losses Locate and configure new development that occurs in tsunami run-up up areas to minimize future tsunami losses Design and construct new buildings to minimize tsunami damage Protect existing development from tsunami losses through redevelopment, retrofit, and land reuse plans and projects Take special precautions in locating and designing infrastructure and critical facilities to minimize tsunami damage Plan for evacuation
Four basic site planning techniques Avoiding inundation areas, using a raised structures above tsunami inundation levels or pier or hardened podiums Slowing water current, using green belt, ditches, slopes to strain the debris from the Steer water forces, implementing paved surfaces that create a low-friction path for water to follow Block water forces, using hardened structures, terraces, berms or parking structures or rigid structures
General Concept on Physical Rehabilitation ti the rehabilitation concept of Calang should be based on design considerations that t avoid and minimise the destruction of tsunami (Darmoyono/Har/Octaviana, 2005): Providing a maximum distance/space between buildings (building with large lot) Locating buildings above the tsunami flood maximum height (vertical evacuation) Locating dwelling areas behind green-belt areas or big and strong buildings Placing main access/circulations outside flood area and supported/secondary access/ circulations at 90 degree angle to coast-line.
Rehabilitation land use planning; ; the settlement should be located in a safe place, with accessible distance to the shore line, and supported by dwelling facilities, commercial (shops, markets), social facilities (bale, meunasah), and public (schools and clinic). circulation; ; this is a very important element for town development. Town with high accessibility can be well-developed with good orientation. Circulations are also made responding to Calang topography. green-belt; ; it will reduce the tsunami effect and prevent building development on the shore line. With the width range from 100 to 200 m and planted with mangroves along the shore the green-belt area could be functioned as a recreation park. circulation green early warning system; ; this is considered as the most important warning mechanism before disaster occurs. In general, citizens must be evacuated into safer place in relatively short time. Traditionally, the information is spread by bedug or kentongan in every house-block (5-10 houses), community centre (meunasah meunasah) ) or higher h ground (escape hills, escape buildings). The traditional communication instruments are used and effectively acceptable as warning system. Certainly, they have to be adjusted with government early-warning system which can fast-detect and warn every bedug/kentongan post.
Land Use Planning Locating temporary fishermen kampongs at radius 500 m from coastline supported by dwelling, commercial (shops, markets), social (bale, meunasah) & public (clinic, school) facilities Green Belt Calang circulation must have major evacuation lines straight to the escape-hill area. A linear-curve circulation pattern is made responding to Calang specific topography
mass evacuation system (horizontal and vertical evacuation); horizontal evacuation is transferring the inhabitants to safer places that is more far and/or higher (escape hill), while vertical evacuation is transferring the inhabitants to high- buildings (escape-buildings) participatory; ; it is obviously clear that without community participation, the field implementation can cause chaos, and without government and social department involved, reconstruction could not be effective. Gampong (Kampong) dwelling design; ; Gampong is Aceh s smallest community structure. It consists of about 125 housing units, meunasah, lampoh jeurat (graveyard), deyan (pesantren Islamic traditional school), krong pade (rice barn) and few bales.
Horizontal and vertical evacuation Escape-hill Analysis, Andi Siswanto Source : Kompas, March 3rd 2005 1. Horizontal evacuation transferring the citizens to safer places 2. Vertical evacuation transferring the citizens to escape hills and high-buildings (escape-buildings).
Shore Area Planning Sea-wall as tsunami wave barrier like most of coastal cities in Japan, but expensive Green-belt zone: coconut-trees/ coast pines or mangroves, can be utilized recreational zone as well
Concluding Remarks Post-disaster recovery requires a holistic approach, such as involving consultation with all relevant stakeholders, taking into account local culture, and environmental aspects including land issues. Preventing the effects by understanding the nature of tsunami.. For the case of Calang the implementation of green-belt area along the shore line with minimum width of 200 m. Decreasing land-use for permanent activities on coastal area.. To some extent, fishermen s s settlement on this area must be supported by proficient Early- Warning System (EWS).
Concluding Remarks Building housing that responds to earthquake and/or tsunami disaster, with spatial planning and building design, careful infrastructure and material and structure. The new re-arrangement of spatial pattern should maintain existing traditional structure and socio-cultural cultural pattern Accomplishing evacuation and early- warning system by using a combination of escape-hills (horizontal evacuation) and escape buildings (vertical evacuation).
Activating shore area/waterfront through attractive public activities in Shanghai.