Through the International City/County Management Association and Local Government Professionals Australia, ICMA’s CityLinks Program has announced that it has matched Semarang -- a port city on the north coast of Java Indonesia looking to address sea level rise -- with the city of Gold Coast, Australia, and coastal modeling resources at Diponegoro University.
Semarang is a fast-growing city in the center of Java, home to 1.6 million people, sitting at less than 10 meters of elevation with some areas below sea level.
The partnership will help the Semarang better understand and address the underlying forces causing its high land subsidence rates -- of 2 to 10 cm per year -- so it can make effective policy decisions through the establishment of coastal management planning.
Coastal Inundation Expected by 2030
According to sea level rise studies based on altimeter data from 1993 to December 2008 and modeling by the Institute of Technology in Bandung, Java, regular tides of 10-20 cm and highest tides of 1-3 meter increases will inundate the northern Javanese coastline with significant flooding by 2030.
The municipality is concerned about potential severe damage to infrastructure, housing, fresh water supplies and economic activities. With most of the city’s coastline owned by private entities, the regional planning and development department Badan Perencana Pembangunan Daerah (BAPPEDA) seeks to protect and regulate the city’s coastline and its people, according to the ICMA.
Regional planners believe that land is subsiding most in neighborhoods with the highest populations and lowest incomes, where it reports that people in these neighborhoods are currently spending “all disposable income” to protect their homes from floods. Turning to CityLinks, a collaboration with the U.S. Agency for International Development, Semarang’s regional planners will now work with Gold Coast’s university students and develop a coastal model.
Coastal modeling using tide, wave and other available data will give BAPPEDA a more accurate picture of the underlying forces causing the high rates of land subsidence, coastal erosion it and its local partners have been measuring for more than 20 years.
Gold Coast has dealt with its coastal flooding problems for more than 30 years, developing a robust coastal modeling program to support coastal management policy decisions. Dr. Hamid Mirfenderesk, natural hazards coordinator of the Australian city’s planning and environment department and CityLinks contact for Semarang, said:
We realize that Semarang was facing problems that our city might also have in the future .. Participating in CityLinks gives us an opportunity to learn from Semarang, as well as share our own knowledge on good coastal management practices.”
Developing a Coastal Management Program in Semarang
Once Semarang officials understand the forces causing land subsidence and sea level rise, they can decide what actions to take, such as:
- Dredging the river
- Building a seawall or jetty
- Relocating sand through a sea pump
- Employing other strategies for making neighborhoods less susceptible to flooding
We have coastal modeling now that will help us to understand what we need to do ... I believe Semarang will learn not how to fight nature, but how to stand its ground and understand how to counteract the transformation that climate change has brought to the city,” said Safrinal Sofaniadi, an urban planner at BAPPEDA.
“The most important thing for me was the fighting spirit of the people of Semarang,” said Mirfenderesk.
