Lake users, including pumpers, boat operators and recreational users, should consider adjusting their activities for changed water levels over the next three months.
MDBA head of River Management David Dreverman said the lake level will be reduced, as early as next week, at a gradual rate to ensure water can still be delivered to the major irrigation offtakes until the season ends on 15 May.
"Once the irrigation season finishes, the lake will be drawn down to 3.5 metres below the normal operating level (121.2 metres Australian Height Datum) by around 1 June 2015," Mr Dreverman said.
"The lake will remain at this level until about mid-July, and depending on inflows from the Ovens and Kiewa rivers, is expected to return to its normal operating height around late July, ready for the start of the irrigation season.
"We are very aware of the importance of Lake Mulwala to the local community, so we've been talking with people in the area to limit any disruption to local activities."
Structural works at the weir include routine testing of anchors and erosion control on the lake foreshore.
"A survey of the aquatic weed Egeria densa in March found that the weed would be completely exposed by lowering the lake by 3.5 metres. This will help stop it spreading to the extent that caused problems in 2009."
Several NSW government agency policies continue to apply during the drawdown. Lake users are advised to consult NSW Department of Primary Industries and Roads and Maritime Services information for fishing and boating advice.
More information on the progress of the drawdown will be updated in future editions of the MDBA's River Operations Weekly Report on the MDBA website.
ENDS
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