Lock 26 at Torrumbarry Weir will reopen on Friday 14 September following successful refurbishment works.
Murray–Darling Basin Authority (MDBA) River Management Executive Director, Andrew Reynolds said the opening of Lock 26 would allow recreational water users to again travel up or downstream.
"Works at the lock were completed with only minimal river traffic disruption and without affecting the normal operation of Torrumbarry Weir in terms of river flow and water supply," Mr Reynolds said.
"The opening of the lock is timely with summer just around the corner and Torrumbarry Weir being very popular with visitors.
"Given the extensive project, maintenance required and surprises along the way, it's been a great effort to get the lock back up and running so close to the winter deadline."
Goulburn-Murray Water (GMW) closed the lock in November last year for repairs. The required work was found to be more extensive that originally estimated.
The lock was de-watered to enable inspection and to allow maintenance, inspection of the sub-floor drainage system and lock foundations, and general inspection of the lock as a whole.
GMW General Manager Customer Operations Scott Barber said the lock's foundations, concrete and drainage components were closely inspected and the maintenance works had been a success.
"These works are vital to ensure the lock continues to operate reliably into the future," he said.
Works also included painting of the gates, and the machining and replacement of new valve frames.
The lock was last fully drained and inspected in 1995, when the original Torrumbarry Weir was replaced with a new, modern structure.
In accordance with the longstanding Murray–Darling Basin Agreement, River Murray operations assets are owned by a 'Joint Venture' comprising of the states of New South Wales, Victoria and South Australia and the Australian Government.
The MDBA is tasked to operate the River Murray system on behalf of the 'Joint Venture'.
GMW is the State Constructing Authority responsible for managing and maintaining Torrumbarry Weir under the direction of the MDBA.
Torrumbarry Weir and Lock 26 are located on the Murray River, about 40 kilometres north-west of Echuca or 80 kilometres downriver of the port of Echuca.
The original weir was constructed between 1921 and 1923 by the State Rivers and Water Supply Commission for the River Murray Commission.