February 2013

Have your say on Queensland's water future

22.02.2013 - Posted by Steve Skull
discussion paper on the future of the Queensland Water Sector was released for public comment late last year by the Queensland Government’s Department of Energy and Water Supply. Comments can be made until Friday 29 March 2013. The strategy will be developed in the remainder of 2013 following a review of submissions.

Interestingly, the discussion paper focuses primarily on water and sewage providers. Unfortunately, its scope does not specifically consider key related areas including water resource planning, broader environmental issues (such as water quality objectives) and national water frameworks.

On the positive side, the paper acknowledges it is the environment that underpins Queensland’s economic growth, development and diverse lifestyles. It also aims for a future water sector that undertakes planning based on catchment boundaries rather than those of local governments, is better integrated, more innovative and, potentially, has a more consolidated funding model.

We would encourage anyone interested in the future of the water sector in Queensland to make a submission.

The Mary River in South East Queensland (photo mrccc.org.au)

Locals in the Surat Basin

19.02.2013 - Posted by Selene Conn
Thought I would share some of the photos of the locals I met during my recent trip to the Surat Basin

We found this Bearded Dragon warming up on some recently burnt grasslands along a tributary of the Condamine River. It was hanging out under this tuft of regrowth, and then flared up when I moved the camera towards its face to show off its broad back and his spikey beard. I also got a great look at the amazing orange lining inside it's mouth, but unfortunately missed the shot as I was jumping backwards at the time…

This one is a male Eastern Water Dragon that I found warming up in this shallow pond north of Miles. You can tell he is male because of the dark line running back from his eyes. This photo was taken right before he took off and proceeded to run bi-pedaly about 5 meters along the waters surface before plunging into the pool. He was about 65cm long and had an amazing greeney-rainbow shimmer to its skin.

We saw a small Eastern Grey Kangaroo swimming across the Condamine River - I thought this was amazing as I didn’t know they could swim, but the water at this point would have been over its head, so it was most certainly swimming! 

And finally, a Lace Monitor gave me a serious fright (and I’m sure I gave it one too) as I must have walked right up to it before it made a HUGE racket running away and up this tree. It was probably over a meter long, and had such amazing patterns.

All of these locals were found near waterways and were probably out and about recovering from the ex-cyclone oswald floods that came through this area the previous week. These creatures are usually found outside of urban areas and need good water quality and lots of trees to be comfortable. Keeping these habitats intact and in good condition will help creatures like this to be around in the future.

Saving water in the northern basin

18.02.2013 - Posted by Kane Travis
I am sure many people have been following the Basin Plan with interest, and in particular the issues associated with water recovery. I thought I might comment on how Alluvium is now involved in the implementation phase of this water recovery.

As part of the Basin Plan the Commonwealth set limits on the amount of water that can be taken from river and wetland systems, called Sustainable Diversion Limits (SDLs). In many cases SDLs were already being exceeded, while at the same time there are landholder concerns about the amount of water available for the irrigation industry to continue to operate and develop.

To manage the problem, the Federal Government essentially has two options to recover water back into the system. The most cost-effective use of public money is to buy back irrigation licences from willing sellers. However this option is largely unpopular with rural communities, where the concern is that if too many licences are bought up and people move out of the region then the whole irrigation infrastructure becomes very expensive for the smaller number of users who remain.

The other option is to recover water through making the system more efficient. The term ‘Environmental Works and Measures’ describes the approach of upgrading infrastructure to deliver and manage water more efficiently.

Alluvium has just been awarded the job to undertake a feasibility assessment of the two highest priority sites in the Murray-Darling Basin in Queensland. One of these investigations is to find engineering solutions to better manage the water regulators in the Lower Balonne.

In the early 1970s a number of weirs were constructed to manage stock and domestic water supply in the Lower Balonne. This had the effect of impacting on flows into the Narran Lakes, further downstream. Our challenge now is to find a solution to achieve a more efficient way to deliver the environmental flows required by the lakes, while managing the needs of stock and domestic users.

To do this we will take into consideration the flow dynamics of the Lower Balonne distributary system with respect to break-outs and effluent flow streams, current operating arrangements of weirs and other private in-stream storages. Bringing together a multidisciplinary team with ecology, river engineering, 2D modelling and economic modelling, we will hopefully come up with solution that improves the heath of the Narran Lakes and offsets the SDL to make more water available for the local irrigation community.

Aerial view of Narran Lakes in March 2008 (MDBC Annual Report)

BRW Client Choice Awards 2013

4.02.2013 - Posted by Kane Travis
We have recently been nominated as a finalist in the 'BRW Client Choice Awards' for 2013. On behalf of all the people at Alluvium, I would like to thank our clients from around Australia and abroad who helped us achieve this.

These Awards are underpinned by the 'Annual Business and Professions Study' undertaken by Beaton Consulting and with over 30,000 survey responses is the largest professional service firm survey of its type in Australasia.

This outcome is important to us. Since our inception we have deliberately focused on honest and open client partnerships, and tried to stay at the forefront of the best science and engineering in our industry. It is very rewarding for our staff that their efforts are recognised in this way.

A final thanks to all those who responded to the survey and provided positive feedback.

Revegetating the economy

1.02.2013 - Posted by Misko Ivezich

I flew out of Brisbane earlier this week for a quick trip back to Melbourne and from the air I was amazed at the volume of sediment flowing into Moreton Bay following the deluge of rain over the long weekend. Later I saw that Canadian Astronaut Chris Hadfield had posted pictures he’d taken from space of rivers all up the Queensland coast, including the Mary River, Burnett River, Calliope River and Fitzroy River. Each picture shows a similar scene to the one I saw over Moreton Bay, tonnes and tonnes of sediment flowing into the marine environment. This would have always occurred after flood events. However research by the CSIRO has demonstrated that sediment loads have increased orders of magnitude over pre European conditions. The sediment is not only impacting the marine environment, I also read that Brisbane’s water supply was also threatened when the Mt Crosby water treatment plant went offline as it was drawing more mud than water from the Brisbane River.

Mary River, Maryborough

Burnett River, Bundaberg

Calliope River, Gladstone 

Fitzroy River, Rockhampton - all images from Chris Hadfield (you can follow him on twitter @Cmdr_Hadfield)

The source of this sediment has been the subject to some conjecture, it had been thought that much of the sediment loads in Queensland rivers had come from hillslope erosion in grazing lands. However recent research by the Australian Rivers Institute has found that much of the sediment is derived from the river channel, from erosion of the river banks. This is consistent with research by Outhet . Bank erosion rates have increased greatly since European settlement due to the clearing of riparian vegetation and uncontrolled grazing of riparian and instream vegetation by stock.

in Victoria the cost of flood related river restoration work has amounted to $80 million (net present value) over the past 20 years (approx). In addition to this river restoration cost, the cost of repairs to public infrastructure (such as roads and bridges) has been an order of magnitude greater again.

Successive Victorian governments have invested in the revegetation of waterways across the state over the past 15 years or so. These programs had been undertaken based on a consensus of opinion among waterway scientists and managers on the benefits of riparian vegetation for stream ecology and for reducing the extent of erosion in flood events. While there was evidence that remnant quality native vegetation limited flood related erosion, there was limited evidence that revegetation programs could achieve the same outcome. It was not until such revegetation had been installed, had time to establish and had been tested by large floods that evidence could be collected on the success or otherwise of revegetation programs in limiting flood related erosion and related environmental, social and economic costs.

A couple of years ago after major flooding in Victoria I was involved in a study that assessed the resilience of some revegetated rivers. The timing of the flooding in Victoria in 2010 and 2011 let us select a range of sites that had been revegetated between 10-15 years ago and examine whether the revegetation had influenced the erosion outcome for the sites. The investigation comprised a paired site assessment where we examined sites that had and had not been revegetated. We found that the vegetation established through the revegetaton programs played the critical role in limiting channel change at the sites.

Suggesting large revegetation programs after flood events is a sensitive issue. To many in the community vegetation is seen to exacerbate floods by blocking up river channels. At the local scale this can be true, however research by the University of Melbourne has shown that vegetation establishment can also be a tool for flood mitigation. Floods travel as waves and these waves will flow through a vegetated river system more slowly than a cleared one. As a result water will be delivered downstream to rural and urban communities at a slower rate with a lower peak discharge if the upstream riparian corridor has been revegetated. Revegetating the rivers and creeks in the upper catchment could be the difference between a flood breaking its levee or not.

With the Queensland government now talking about large scale flood mitigation programs (such as levees and new dams) the role revegetation can also be examined as a cost effective means of not only reducing the peak discharge (and extent of flooding) but the damage associated with flood related erosion. Large scale revegetation of rivers and creeks across Queensland could have significant benefits to the economy. The benefits would include reduced damage to public and private infrastructure from erosion, potential reduction in peak flood levels and as a result the number of properties inundated following floods, a reduction in sediment being exported to the marine environment which have some big tourism drawcards such as the Great Barrier Reef and Moreton Bay and large reductions in water treatment costs. And after all that we’ll end up with much healthier rivers too.