Aqwest Reservoir standing safely on high ground

The Project

Aqwest's Roberts Reservoir, a crucial water storage facility servicing the city of Bunbury in Western Australia, holds up to 13 million litres and requires ongoing structural & geotechnical monitoring in order to maintain asset security. Recent surveys identified the need to protect embankment gradients from risk of erosion & subsequent slope failure. Global Synthetics role was to provide a reliable and cost-effective solution to confine topsoil, promote successful revegetation, improve native landscape, and ensure the long-term stability and protection of this vital utility.

The Challenge

Despite reprofiling efforts, some of these batters could not be constructed any shallower than the desired 1:3 gradient. This posed a significant challenge, as finding a solution for long-term erosion protection of such batter angles was crucial. Aqwest needed a product that would retain introduced topsoil, ensuring it remained in place during heavy rain events and facilitate growth of vegetation.

Our Solution

Global Synthetics partnered with local contractor Carbone Bros Pty Ltd to address the project's unique requirements. Global Synthetics supplied 150mm deep Miracell® Cellular Confinement System, tailored to meet Aqwest's specifications. Miracell® CCS provides an ideal cell aperture for effective soil confinement and planting. Its large, expanded panel size hastens installation, resulting in improved efficiency. To ensure the system's integrity on the steeper slopes at the Aqwest site, we provided Miracell® CCS accessories, including structural nylon tendons, anchor heads, and connection keys. Additionally, our Geofirma® AS350D nonwoven geotextile played a crucial role in separating and filtering the topsoil fill from the sandy subgrade beneath.

The Results

The implementation of Miracell® CCS, combined with Geofirma® AS350D geotextile, delivered outstanding results for Aqwest's Roberts Reservoir, safeguarding the stability of the reservoir’s banks for decades to come. Moreover, the reintroduction of endemic vegetation has enhanced the local biodiversity and created a more visually appealing environment.

“Not only are the banks more stable and less prone to erosion, but additional vegetation and trees will greatly improve the amenity of the area for the local community” - Cristiano Carvalho, Aqwest's General Manager for Water Services.

If you have a similar application or are looking for solutions to slope erosion or soil stability issues, please contact the team at Global Synthetics. Our qualified engineering staff can assist with technical advice and preliminary designs for your next project.