GHD together with joint venture partner Stantec has been awarded an AUD14.5 million concept design contract for the proposed raising of Warragamba Dam, which stores approximately 80 percent of Sydney’s drinking water supply.

The Warragamba Dam Raising proposal is one measure being implemented to reduce flood risk in the Hawkesbury-Nepean Valley. The raised dam would temporarily hold back and then control the release of floodwater coming from the Warragamba catchment in large flood events.

“We are proud to be involved in the upgrade of one of Australia’s iconic dams for the benefit of downstream communities. To design the significant modifications needed for the new flood mitigation function, our team brings design and construction experience from major dam projects in Australia and internationally as well as a track record of successfully delivering a variety of projects for WaterNSW,” says Steve Fox, project director and past chairman of the Australian National Committee on Large Dams.

The Hawkesbury-Nepean Valley has the highest flood exposure in New South Wales. Since the construction of the Warragamba Dam in 1960, 20 moderate to major floods have affected the valley.

The dam is currently not designed or approved for flood mitigation.

GHD has been working on dams since the company's birth almost 90 years ago and has designed the Enlarged Cotter Dam, the highest roller-compacted concrete dam in Australia.