As the threat from the sea grows, the Philippines is moving away from using concrete in favor of natural solutions. Sea-level rise caused by climate change poses a serious problem for many coastal areas worldwide. High waves, storm surges, and slow land subsidence increase the risk of flooding in coastal settlements.
The small island of Pamarawan, located north of the Philippine capital Manila, is also facing this issue. Local residents, numbering about 3,000 people, have long tried to protect their homes from floods by building concrete barriers, but the threat of water kept recurring. Now, the islanders have chosen a different approach to solving the problem.
Instead of constructing massive concrete walls, they are attempting to weaken the force of ocean waves and strengthen the coast using bamboo, wood, and discarded mollusk shells.
Pamarawan's geographical location makes it extremely vulnerable to floods and sea storms. During strong storm surges, seawater penetrates inland areas. This situation is exacerbated by rising sea levels due to climate change and the subsidence of the land itself. Rising sea levels increase the probability of water intrusion into coastal zones, while land subsidence causes the island's height to decrease relative to sea level.
Local inhabitants have repeatedly built new concrete layers and raised their houses for protection. However, this method has proven to be a short-term solution. While raising houses may provide temporary relief, it does not reduce the force of ocean waves or ensure the safety of the entire coastal area. When strong waves and floodwaters constantly attack the shore, simply raising individual houses is insufficient; measures that can reinforce the natural barrier between the sea and the land are required.
In Pamarawan, a natural barrier is being created along the coast using bamboo poles and shrub-like wood. This initiative was started after a study conducted by the city government of Malolos in collaboration with a Dutch engineering consulting firm. This island falls under the jurisdiction of the city of Malolos.
Starting last May, local residents and other workers began installing bamboo poles along the coast. Between these poles, they are filling with wood and shrubs. The goal of this project is to slow down the flow of water coming from the sea. When the water speed decreases, silt and sediment carried by the water can settle behind these barriers. There is hope that this will help raise the height of the seabed over time.
This method is not based on completely stopping the sea, but on reducing its energy. When strong waves hit the shore directly, they can wash away soil and intensify coastal erosion. However, the bamboo and wood barriers are capable of slowing wave movement. This allows sediment brought by the water to settle, helping to stabilize the coastal land.
Another important part of the project is the use of discarded mollusk shells in the sea. AFP journalists visiting the site observed workers building a breakwater, which reduces wave force, approximately 100 meters from the shore, using mollusk shells.
