The weir pool will be lowered for up to 10 weeks while repairs are made to the concrete structure on the riverbed and six new mechanised trestles are installed.
The weir pool will be gradually lowered over seven to nine days to about 3.6 metres below full supply level, depending on river flows, and is expected to return to full supply level by late July.
Works on the lock chamber are also planned to start on 20 May 2015. The lock will be closed to boat traffic from 4.30pm that day, and will remain closed for three to four months while the lock is refurbished. The extent of work to be completed on the lock can only be determined once it is empty and can be inspected.
MDBA head of River Management David Dreverman said the timing of the works was made after speaking with local community and industry groups.
"We're very aware of the needs of the many river users so we've taken the advice of local tourism, industry, irrigation and other groups to identify the preferred timing to do these necessary works," Mr Dreverman said.
Boat operators, stock owners, river pumpers and other river users are advised to take these changed water levels and the lock closure into account and make any necessary adjustments to their activities.
River salinity might increase during the drawdown, depending on flow rates at the time. Salinity levels will be continually monitored and available each Wednesday morning on the MDBA website
Updates prior to and during the works will also be available in the Weekly Report
ENDS
Contact the MDBA Media office at media@mdba.gov.au or 02 6279 0141.
Follow the MDBA on Twitter: @MD_Basin_Auth
Access information and discussion on the MDBA blog: http://freeflow.mdba.gov.au/