ITS Campus, ITS News — The tragedy of Mojokerto Junior High School 7 students being swept away by waves known as rip currents at Drini Beach, Jogjakarta, some time ago, should be a concern for the wider community. People need to know more about how dangerous rip currents are and how to be aware of them when playing in the water by the beach.
Examining this, lecturer at the Department of Marine Engineering Institut Teknologi Sepuluh Nopember (ITS) Dr. Ir Wahyudi MSc explained that rip currents occur when ocean waves approaching the coast break and turn into a flow of water that is deflected by the coastline to an area with low energy. Especially in bay-shaped coastal areas, it often has a strong rip current energy. “It looks frothless and calm, but it has rip currents in it,” he explains.
The man from Jogjakarta added that beachgoers should be aware of areas of water on the edge of land that appear calm, flanked by bubbly waves. Rip currents have great potential to occur throughout the southern coast of Java because it is directly facing the Indian Ocean. Although the waves heading towards the coastline are random and unpredictable, beaches bordering the open ocean certainly have high incoming waves.
Furthermore, this oceanography expert said that rip currents’s speed can occur from 0.85 to 1 meter per second. Not only does the rip current return to the middle of the sea, but the current with a width of about 9 to 11 meters also carries sediment around the coast to the middle of the sea. So areas where rip currents often occur appear calm and dark because a trough has formed. “The current is so fast that even Olympic swimming champions will not be able to fight the rip current,” he warned.
It should be noted that rip currents do not occur in certain seasons and cannot be determined how many times a day. But what can be watched out for is when on a hugging beach or the edge of a cape, because these areas have the strength of rip currents that can wash away humans. “Hydro-oceanographic conditions and coastal morphology are things that affect this rip current,” said the man who is a member of the ITS Coastal and Port Infrastructure Laboratory.
The incident that happened to several students of SMP 7 Mojokerto is a small example of the many victims of drowning due to rip currents. In Indonesia, casualties due to rip currents on the south coast of Java continue to increase from 2017 to 2022. The latest data states that nearly 50 people have died from being swept away by these currents. “Rip currents can pose a threat to beachgoers. They cannot be eliminated, but they can be avoided,” he said.
The most important thing to avoid further rip current casualties is to mitigate the threat of these deadly currents to all visitors. It is important to socialize the dangers of rip currents through seminars or schools in Indonesia. In addition, it is also necessary to improve beach support facilities such as fast boats, buoys, and reliable lifeguards. If visitors are caught in a rip current, they are required to avoid the current by swimming sideways, parallel to the beach.
In conclusion, the lecturer of the Oceanography course hopes to be able to promote more massive socialization to all levels of society, especially for schools that choose the beach option as a place of recreation as well as learning. He invites volunteers who have high empathy to fight together as instructors and intensify socialization about the dangers of rip currents. “Of course, the local government must also take part in this socialization,” he concluded.
The socialization of the dangers of rip currents is by Sustainable Development Goals (SDGs) 13, namely actions to address climate change. The socialization of the dangers of rip currents is also related to several other SDGs. These include SDG 3 on good health and well-being (by reducing the risk of injury or death from rip currents), and SDG 11 on sustainable cities and communities (by increasing public awareness and preparedness for the hazards of rip currents in coastal areas). (ITS Public Relations)
Reporter: Ahmad Husein Al Qomary