The situation of the coastal area of Banda Aceh based on aerial image taken in February 2018.

TDMRC Research: Raised Banda Aceh Outer Ring Road Could Reduce Tsunami Impact

A 7-km embankment along the coast of Banda Aceh where a road was constructed at the leeward side of the embankment
A 7-km embankment along the coast of Banda Aceh where a road was constructed at the leeward side of the
embankment

A research carried out by a joint team led by Dr. Syamsidik shows that the planned Banda Aceh Outer Ring Road (BORR) could be an effective tsunami mitigation measure if built to the height of 5 meters above sea level. This study was inspired by the tsunami multidefense system built in Tohoku, Japan following the 2011 Great East Japan Earthquake and Tsunami. The system includes outer city toll roads which are elevated by up to 5 meters.

Banda Aceh Outer Ring Road (BORR) is one of the infrastructure development projects devised in the city’s new mid-term development planning.  The road is expected to span along the periphery of Banda Aceh, parallel to the coastline. This makes the road a great potential as a tsunami defense measure.

To test the effectiveness of the raised road as tsunami defense, the researcher used Cornell Multi-Grid Tsunami Coupled Model (COMCOT) tsunami simulation program. The computer simulations were carried out based on two earthquake magnitude scenarios: 8.5 and 9.15 Mw, and two coastal morphology scenarios: with and without elevated BORR. The city’s 2029 land use planning, which includes maintaining the fish pond and salt marshes area as it is, was also included as a parameter.

The elevated road (yellow line) is part of the city’s development planning documents.
The elevated road (yellow line) is part of the city’s development planning documents.

The simulations then demonstrated that the elevated road coupled with the 2029 land use plan could reduce tsunami inundation area by about 9% and 22% for 9.15 and 8.5 Mw earthquakes, respectively. The team therefore suggest the Government of Banda Aceh to adopt the elevated roads in the BORR constructions as this will significantly help the city to cope with future tsunamis.

This research was conducted by a joint team from Universitas Syiah Kuala (Indonesia), Tohoku University (Japan), and University of Pittsburgh (USA), under the grant from the Partnership Enhanced Engagement in Research (PEER) cycle 5 sponsored by the USAID and National Academies of Sciences of United States (NAS). The research article was written under the World Class Professor 2018 scheme B, promoted the the Ministry of Research, Technology, and Higher Education of Indonesia (RISTEKDIKTI).

The full research article is downloadable here.