Construction is underway on a dam upgrade that is expected to improve safety and secure long-term water supply for the Sunshine Coast.
The Lake Macdonald Dam Improvement Project includes construction of a temporary cofferdam, a new concrete spillway, an upper labyrinth and the reconstruction of existing earth embankments to enhance the dam’s ability to withstand extreme weather events.
Seqwater executive general manager infrastructure planning and capital delivery Sarah Dixon said the works would contribute to the longevity of an important local water source.
“Lake Macdonald Dam was built in 1965 to the safety standards of its time but the methods used to estimate extreme weather and flood risks have changed significantly since the dam was originally built,” she said.
“Seqwater is proud to mark a major milestone in starting construction on the Lake Macdonald Dam Improvement Project, together with our head contractor John Holland.
“The dam upgrade will continue to ensure long-term water supply reliability for the Sunshine Coast region.”
Want more free local news? Follow Sunshine Coast News on Facebook, LinkedIn and Instagram, and sign up for our FREE daily news email.
The large siphon system has been switched on and is partially lowering the lake to allow the works to be undertaken safely.
Works have also commenced on the temporary upstream cofferdam, with a 250-tonne crane onsite.
More than 1500 tonnes of sheet piles are being delivered to form the structure of the cofferdam, and more than 3000 rock bags – each weighing about eight tonnes – are being placed downstream of the cofferdam to provide additional structural support.
In addition, more than 80,000 tonnes of rockfill is being delivered to build the cofferdam.
This will be the first major upgrade of the dam since its raise in 1980.
More than 150 jobs are expected to be supported over the life of the project.
Standard work hours are Monday to Friday from 6.30am to 6.30pm and Saturday from 6.30am to 4pm. Extended work hours will be required for some construction activities, including spillway demolition.
During construction, there will be an increase in traffic around Lake Macdonald.
Temporary traffic changes will occur and traffic controllers and temporary signage will be in place when required.
Recreation activities on Lake Macdonald via Lake Macdonald Park and the Noosa Botanic Gardens will remain open. However, some recreational use of the lake and surrounding areas will be temporarily closed for safety due to proximity to the construction area.
Seqwater thanked community members for their ongoing patience and support during the upgrade, which is expected to take about five years to complete, weather and site conditions permitting.
Seqwater has delivered 13 dam upgrades since 2008, including Leslie Harrison Dam at Capalaba, Sideling Creek Dam north of Brisbane and Ewen Maddock Dam on the Sunshine Coast.
