System analysis Palawan Beach and Lagoon

Palawan Beach is a beautiful white sandy beach fringed with palm trees and azure water. However, there is an issue with the water quality. There are several potential causes, including excessive nutrient levels leading to algal overgrowth, excessive movement of sand or a combination of the two. In the Palawan Beach and Lagoon project in Singapore, Witteveen+Bos was asked to provide a second opinion on an existing design intended to resolve the water quality problem in Palawan Bay.

Different causes require different interventions. The present design would see the bay turned into a lagoon through a complex system of 14 measures. ‘While developing the second opinion, it was clear to us right away that any solution would require quite a few measures’, says Guus Kruitwagen, Witteveen+Bos project leader and ecologist. Previous interventions have had the effect of multiple band-aids stuck on top of each other to cover a single wound. The fact that no single, properly dimensioned bandaid was in place also made it clear immediately that no proper system analysis had been conducted beforehand. The proposed closure of the bay would involve a significant risk of ecological water quality issues. Together with a local agency, Witteveen+Bos monitored the situation for a full year. It turned out that the water quality deteriorated when the waves rolled towards the beach in a particular way. The conclusion was that the impact of waves on the beach had to be reduced in a way that would not cause any secondary problems.’ The solution contributed by Witteveen+Bos was to achieve attenuation of the waves by means of a floating bridge, rather than to close off the bay entirely, thereby resolving the water quality issue without interfering in the exchange of water with the open ocean.

Thanks to the prior system analysis, we could offer a solution without replacing one problem with another. Guus Kruitwagen: ‘Being ecologists, of course we always include nature in our designs. In other disciplines, people are sometimes unaware of how confined they are by their own specialisation, resulting in designs that fail to take the wider context into account. As a matter of fact, every discipline should conduct its own system analysis. Because listening to nature and other key processes can add a lot of value.’