The Geobarrier System (GBS) was jointly developed by the Housing Development board (HDB) and Nanyang Technical University (NTU). It is a climate resilient solution which will maintain slope strength during heavy rainfall. The difference in permeability in the distinct layers of the GBS allows rainwater infiltration to be directed away from the slope, preventing oversaturation.


A Climate Resilient Solution

The GeoBarrier System comprises of 3 main layers – an exposed vegetative layer using approved soil mix (ASM), fine-grained layer, and coarse-grained layer .


The fine- and coarse-grained layer has distinct hydraulic properties that creates a “barrier effect”, allowing the rainwater to be diverted away while keeping the slope at high stability. This reduces risk of flooding in urban environments which is also increasingly becoming a problem due to climate change.

GeoBarrier System layers

As Singapore is located in the tropical region characterized by intense rainfall, it experiences two monsoon seasons yearly. During the wet monsoon season, slope failures occur frequently, especially to slopes which have high pore water pressure buildup. Due to a period of continuous torrential rainfall, our client’s boundary retaining wall collapsed.

Case Study

A look at the first private development adoption case study where a traditional retaining wall is replaced by the GeoBarrier System.