Along the coast of Singapore’s Pulau Ubin, abandoned aquaculture ponds and higher wave energy created by vessel movements are eroding the island’s mangrove habitats and removing sediment away from the foreshore, resulting in the retreat of the shoreline.
This is especially problematic as mangrove forests are considered one of the most effective nature-based solutions in the fight against climate change. They have the ability to capture over three times the amount of carbon than tropical rainforests, as well as protect shorelines from storms and floods.
To tackle this issue, Singapore is turning to nature-based solutions. AECOM’s multi-disciplinary team has since 2018 been working with the National Parks Board (NParks) of Singapore to conduct detailed design consultancy and environmental impact study (EIS) on the island’s shorelines.
Sustainable, nature-based solutions
The Pulau Ubin project is in line with the principles behind the United Nations Climate Change Conference (COP26), demonstrating how industry participants and stakeholders can innovate and build partnerships for the good of the environment.
It also reflects AECOM’s commitment to our ESG strategy, allowing us to come up with a holistic approach in analyzing the problem and finding a sustainable and effective solution.
Key to the success of the project will be identifying methods to prevent further erosion, while having minimal impact on the surrounding area. The solution has been to install headlands made of armor rocks and rock revetment features beneath eroded mangrove undercuts.
The headlands, separated 200 meters apart by beach nourishment sand, will act as barriers and advance the shoreline beyond its current location. They will also feature intertidal habitats with different elevations for perching and roosting birds, as well as rock pools and crevices for marine intertidal fauna and saltwater tolerant plants to naturalize and enhance the habitats.
Protection measures for the existing mangrove forests will involve the construction of rock revetments along the eroded shorelines. Suitable substrate backfill inside 100 percent biodegradable coir fiber bags will be placed beneath these sloping rock revetment structures to help the natural colonization of the mangroves along the revetments.