The River Murray, a ‘working river’, is regulated with dams, weirs and barrages to help ensure a reliable source of water for communities along the river. These structures, however, have disrupted natural flooding patterns which the floodplains and wetlands along the river rely on. To help restore the balance, The Living Murray program is funding the construction of major water management structures that will help deliver water at several icon sites along the River.
One of these major construction projects is happening at Hattah Lakes, near Mildura. Hattah Lakes is one of The Living Murray’s six icon sites and contains 12 Ramsar-listed wetlands.
Construction of the Cantala regulator. The regulators are designed to not impede natural water movement along the creek lines, but can be closed for managed watering events. This regulator is 100 metres wide and will stand 5 metres tall. The sheet piles are not yet completed and the concrete works have just commenced.
Photo: Heather Peachey.
Helping to restore environmental values
The aim for the Hattah Lakes icon site is to preserve and, where possible, restore healthy examples of the original wetland and floodplain communities. The engineering works will provide regulators and levee banks, which will be used to deliver and hold water at the site.
An aerial view of Hattah Lakes from the north-west. This flooding was in March 2011, with flows in the River Murray as high as 70,400 ML/day at Euston Weir. The engineering works aim to achieve the same level. The works are flexible enough to increase the extent and duration of a natural flood by closing the regulators when the floods recede and pumping additional water into the system.
Photo: Brendan Rodgers, Parks Victoria.
The engineering works aim to water the central lakes using natural river and wetland connections for small and medium floods in the River Murray. Pumps will be used to top up the lakes to a particular level that will reflect the level they would have filled to if the river was not regulated. This level will be determined using:
- historical, actual and modelled natural events
- the ecological aims at the time
- the volume of environmental water available.
After watering, water will return back to the River Murray via the natural waterways of Chalka Creek.
This pipe will deliver water from the pump station to south Chalka Creek.
Photo: Rachel VonGerhardt.
The engineering works will enable nearly 6,000 hectares of wetland and floodplain communities to be watered, including all 12 Ramsar-listed wetlands at the site.
Construction of the land-based works is expected to be completed in time for a spring watering this year, if there are high flows in the Murray. Environmental water will be sourced from a number of sources including The Living Murray, the Commonwealth Environmental Water Holder and the Victorian Environmental Water Holder.
The pumps will be installed in summer to take advantage of low river levels.
To find out more, visit the MDBA website and the Mallee Catchment Management Authority’s info on Hattah Lakes.
TLM: Major Engineering Works for Hattah Lakes,
I agree with Andrew – a simple answer please.
The Hydrologic Modelling to inform the proposed Basin Plan (MDBA 2012) reads (emphasis added):
“…For Basin Plan purposes the presence of TLM environmental works did not result in modification of environmenal water requirements (flow indicators) for TLM icon sites…..TLM works DID NOT contribute ...
... to an offset in the proposed reduction in diversions.” (p196)
Can you please explain how the works and measures “are in the model now”, as Dr Dickson said on ABC. Is there new modelling? Are the works incorporated but the benefits of using them ignored and therefore offsets are not accounted for?
Specifically for Hattah Lakes in the same modelling report (p201) it says:
“Envrionmental water requirements for Hattah Lakes have not been modified to take into account the presence of works…….The implications of works at a particular site on broader environmental outcomes is a complex trade-off to consider. As such the MDBA will seek to make an infomred assessment for input into the 2015 review.”
As this review has now been replaced (in principal) by the adjustment mechanism, one would assume TLM works would be looked at for these purposes, yet the MDBA is now saying they don’t need to because they have already been assessed and incorporated into modelling.
Can we please see that modelling? Clearly it is not the 2012 report so it must be new, as yet unpublished information.
Hello Erin,
Thanks for your reply. Yes, I’ve read the ABC news article – but that doesn’t provide the yes or no answer that I’m looking for on behalf of the thousands of stakeholders affected by this.
What people want – and what we’d be most grateful if you could provide here ...
... – is a simple answer; are savings generated by The Living Murray to be deducted from 2,750 or not?
Please accept that the confusion over what is a very simple question has been caused by obtuse answers in the past. I think it would be extremely useful for everyone concerned to have a straightforward answer to this one at the earliest opportunity.
Andrew Gregson
CEO
NSW Irrigators Council
Can you please confirm that this is one of The Living Murray projects that may or may not be included in the reduction volume? Please confirm that Craig Knowles said “they need to be accounted for” in a video message but that the MDBA now contends that these works are ...
... already accounted for in the baseline, which is disagreed by Victoria and New South Wales.
Perhaps you might provide a simple analysis on here – given that you’ve raised subject – or why these efficiency works are included or excluded?
Hi Andrew
Yesterday our CEO Dr Rhondda Dickson spoke to the ABC about this issue.