Murray–Darling Basin Authority (MDBA) general manager river operations Andrew Reynolds said boats would not be able to access the lock until the maintenance is completed.
"An issue with an upstream lock gate was identified yesterday," Mr Reynolds said.
"WaterNSW is working to address the issue. This will involve using a crane to lift the gate out.
"While the crane is onsite, we will check all of the lock gates to ensure there are no other problems.
"We know there are many people using the river at this time of the year so we will be working to fix the gate as soon as possible.
"The maintenance will take at least one week. However, there could be further delays to boat traffic into late January if additional work is identified."
The water level in the Euston weir pool will not be affected.
Boat operators and other river users are advised to take this lock closure into account when planning their activities on the river.
ENDS
For more information, contact the MDBA Media office at media@mdba.gov.au or 02 6279 0141
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