Bamboo and oyster shells: Philippine island fights rising seas with nature, not concrete

For years, residents of Pamarawan Island, located north of Manila, have struggled with floodwaters threatening their homes, despite building them atop layers of concrete. The 3,000 inhabitants sought a nature-based solution to combat rising seas, resulting in a unique project using bamboo poles and oyster shells. The project, initiated by Malolos city government, faced initial resistance but was deemed necessary by Mayor Christian Natividad.

Bamboo poles and coconut-fibre bags filled with oyster shells have been installed along the coast, aiming to slow water flow and trap sediment, gradually raising the seabed and supporting mangrove growth. The project, which cost 70 million pesos, covers about 14 hectares along Manila Bay and is estimated to be more cost-effective than conventional concrete seawalls.

While its long-term effectiveness remains uncertain, the project has already provided relief to residents, with fisherman Edgar Javier noting a significant reduction in wave impact. The success of the project will be determined over the next decade as mangroves grow and sediment accumulates, providing a more robust natural barrier.