SA Water’s refurbishment of Lock Three on the River Murray will begin in mid-June, meaning that it will soon be drained of its nearly eight million litre capacity of water in preparation for the works.
SA Water’s Senior Manager of River Murray Operations, Garry Fyfe, said prior to the temporary emptying of the lock chamber, divers and a mini uncrewed submarine equipped with a camera will explore beneath the Murray’s surface.
“The ROV, or Remote Operated Vehicle, is used by various SA Water operations teams to take high-definition video and images of underwater structures including weirs, reservoirs and other water storages,” Mr Fyfe said.
“We will be operating it from a trailer away from the water’s edge, and together with the skills of the divers, it will help determine the priority of maintenance based on the condition of the lock as seen in the captured footage.
“While it would realistically take only about five minutes to drain the lock chamber, we will be doing it gradually over a two-week period to allow preparatory works, such as the underwater investigation, to be carried out.”
Lock Three opened to river travel in 1925, as part of the Murray Waters Agreement of 1914 and the River Murray Act of 1915. The agreements provided for the construction of permanent navigation to allow the safe travel of boats and other river users travelling up or downstream during all types of flow events.
Construction of the lock in the early 1920s created a major upsurge in the local population, with required workers moving to the region. Traffic through the township along the River Murray also increased, as people travelled to the new irrigation settlements in the wider Riverland area.
“These days, around 4000 people on vessels ranging from small tinnies to huge paddle steamers pass through Lock Three every year, so it’s important we maintain it, to ensure its longevity and continued safe and efficient operation,” Mr Fyfe said.
“The refurbishment will take up to 14 weeks to complete, with a range of work to be undertaken including repainting the lock gates; replacing gate seals and bottom fenders; rehabilitating upstream and downstream valves and tunnels; and replacing all cathodic protection works.”