Extreme Tidal Floods in Coastal Central Java, A Strong Warn for Us

KlikFakta.com, Central Java – Since Tuesday (24/5/2022) several cities in Central Java Province have been hit by tidal waves and tidal flooding.

The National Disaster Management Agency detailed 13 tidal flood-prone areas, including the Brebes Regency, Tegal Regency. Tegal City, Pemalang Regency, Pekalongan Regency, Pekalongan City, Batang Regency, Kendal Regency, Semarang City, Demak Regency, Jepara Regency, Pati Regency, and Rembang Regency.

Apart from the levee breaking at Tanjung Emas Port, Semarang, several other factors also caused the tidal flood which forced hundreds of people to evacuate.

A hydrologist from Diponegoro University, Suripin, explained that the tidal flood that hit the north coast of Central Java was getting worse because some of the land area was below sea level. This is because land subsidence continues.

Based on a study conducted by Suripin and early in 2012, land subsidence in Semarang City reached 10-13 centimeters every year.

“This happens because the water is constantly trying to condense itself, so the condition continues to decline. The solution to reduce the rate of land subsidence can be done by taking groundwater. However, this cannot be done immediately because the community’s water needs cannot be fully met by regional drinking water companies without groundwater extraction,” said Suripin, Wednesday (25/5/2022).

As said by the Advocacy and Campaign Manager of WALHI Central Java, Iqbal Alma, the many developments and exploitation of the environment are the causes.

“This disaster has become a disaster that seems to have been invited by humans, especially policy makers. Tidal floods continue to occur every year, industrial development in coastal areas is still being carried out,” said Iqbal in his official statement, Wednesday (25/5).

The phenomenon of land subsidence on the coast of Central Java has made several researchers predict the sinking of several areas. Head of the Geodesy Laboratory from ITB, Dr. Heri Andreas predicts that the cities of Pekalongan, Demak, and Semarang are threatened with drowning because the land subsidence in Pekalongan-Demak reaches 15-20 cm per year.

Meanwhile, Professor of the Faculty of Fisheries and Maritime Affairs at Diponegoro University, Prof. Dr. Denny Nugroho Sugianto, also said that the northern area of ​​Semarang could sink in 50 years if there is no treatment.

According to detik.com, the Regional Secretary for the City of Semarang, Iswar Aminuddin, suggested that the prediction of the sinking of Semarang should not happen.

“(Sink prediction) Oh no. Actually we ordered the embankment (Semarang-Demak Toll Road) there are 220 hectares of land for pond retention. So later you can no longer use groundwater. You can fill the groundwater cavities again,” said Iswar to detikJateng, Friday (27/5/2022).

He admitted that there was land subsidence. So, currently, technology is being pursued to contain sea water. He hopes that all parties cooperate with each other.

“When there is land subsidence, it needs management. I think there must be technological innovation, how then we can add this dike every year, so there are some kind of plates, we will add more later, if we don’t add more,” he explained.