Review of January 2017 Operations
No measurable inflow was observed to reservoirs for a second consecutive month during January. Between July and January 67,250 ML of inflow has been recorded into headworks storages, which is 39% of the historic average for the same period (170,300 ML).
During January, the volume in headworks reservoirs decreased from 331,190 ML (59.2%) to 303,960 ML (54.25%).
Rainfall was below average at all reservoirs during January. The highest rainfall for the month was 14mm, recorded at Lake Bellfield.
Environmental water releases continued during January, with 980 ML supplied from Lake Wartook to the MacKenzie River, and 180 ML released from Lake Lonsdale to provide baseflows to the lower Mt William Creek. Environmental water releases from Taylors Lake commenced in early January, with 1,400 ML delivered to Wimmera River. Rocklands Reservoir also released 2,550 ML of environmental water and 1,120 ML of passing flows to the Glenelg River.
Wimmera-Mallee Pipeline supplied Recreation Lakes received 208 ML during the month.
Consumptive entitlement holders collectively used 1,920 ML during January to supply urban and rural demands.
Due to below average rainfall, net evaporation from reservoirs was approximately 11,000 ML for the month; with evaporation exceeding rainfall, (Net evaporation considers rainfall on the reservoir as an evaporation offset).
Planned February 2018 Operations
The Bureau of Meteorology (BoM) in their most recent climate outlook predict a 60% chance of above average rainfall this February. Current predictions are also for El Niño–Southern Oscillation (ENSO) to continue in a weak La Niña phase. La Niña events have historically brought above average rainfall to south eastern Australia during summer, however the weak nature of the current La Niña conditions mean that there will be less influence on rainfall. La Niña events can also increase the likelihood of prolonged warm temperatures.
No water transfers are currently planned for February, however the Storage Manager will continue to monitor conditions. Further information in relation to water transfers are described in the Storage Manager’s Annual Operating Plan.
The release of environmental water and the routine delivery of water to consumptive entitlement holders is expected to be the Storage Manager’s operational focus during February.
Reservoirs are expected to remain at suitable levels through February for a range of recreational activities, including boating at reservoirs where this is permitted. Please refer to the Reservoir information page for further information on water levels and recreation activities permitted at each reservoir.
Blue-Green Algae blooms can be more common during the warmer summer months. Recent Blue-Green Algae warnings for reservoirs can be found on the Storage Manager News Feed and all current warnings are available from the GWMWater Algae Warnings webpage.