Public Works Committee: Tod River Dam Safety Upgrade Project

Ms DIGANCE (Elder) (11:21): I move:

That the 554^th report of the committee, entitled Tod River Dam Safety Upgrade Project, be noted.

The Tod River Dam is situated on the Toolillie Creek (I have the member for Flinders here who can guide me, so that is good), a tributary of the Tod River over on Eyre Peninsula. It is around 27 kilometres north of Port Lincoln in the Whites Flat and Koppio area. The dam was constructed between 1918 and 1922 to supply water to Eyre Peninsula. It has a maximum capacity of around 11.3 gigalitres.

Since 2002, the dam has been offline due to water quality issues and is no longer used to supply water on Eyre Peninsula due to the high salinity levels. This is being actively managed by SA Water, but the water remains well above drinking water standards, as well as being unsuitable for agricultural use. In addition, in recent years the level of the water has been reduced to around 8 per cent of its full capacity.

SA Water constantly monitors all its assets, including dam infrastructure, to ensure compliance with national standards. In this case, the Australian National Committee on Large Dams (ANCOLD) guidelines are used. Safety and risk assessments conducted on the Tod River dam have identified that the dam is noncompliant with current ANCOLD guidelines. Given that SA Water has an obligation to manage all its dams safely and manage the risks, and has a commitment to comply with the ANCOLD guidelines, it has proposed these works as an effective and efficient means of upgrading the dam to ensure compliance with the guidelines.

These works were considered by SA Water for the upgrade. They were a standards-based upgrade, a partial decommissioning, a full decommissioning, and a hybrid option, being a phased dam safety standards-based upgrade with a lowered full supply level. The latter is the preferred option, supported by both the economic and financial analysis. It also allows the dam to remain online for current recreational use and other potential future uses. The cost of the preferred hybrid option is $6.305 million (GST exclusive). It will see the water level maintained at the current 8 per cent.

When questioned by the committee on why, other than cost, the dam is being decommissioned, SA Water said that they were keen to maintain the dam to allow for potential future uses of the water. Although investigations already undertaken have identified that it is not cost-effective to treat the water to drinking water standards, in the future there may be potential to treat the water to a lesser standard for, say, irrigation or mining purposes, should there be a demand and also if it is economically viable.

The Tod River Dam is an important piece of local infrastructure, from both a water perspective and a historical perspective. It is listed on the South Australian Heritage Register, recognising its historical significance as an early water supply for Eyre Peninsula. SA Water has been working with the heritage section of the Department of Environment, Water and Natural Resources to ensure that the works are in keeping with the surrounds and heritage value.

There has been a significant amount of consultation with the community, local members of parliament, the member for Flinders, and the local councils. This is a very important project for the region, and the community is highly interested in the project, given the importance of water issues on Eyre Peninsula. This is reinforced by the discussions the committee had with local government representatives during our visit to Lower Eyre Peninsula last year.

It is to be remembered that this project is about safety and potential risks that could occur in an extreme event, including potential loss of life, loss of key infrastructure and local property damage. It is not about addressing water security, either water quality or quantity for Eyre Peninsula. SA Water will continue to consult with the local community throughout the project, and it has taken on board the other concerns the community has raised, including that of water security.

I would like to thank the member for Flinders, who attended this particular committee meeting when we had witnesses and gave his evidence and perspective on behalf of the local community from his area. I would also like to thank all my other committee members, and our hardworking support staff to the committee. With that, and given section 12C of the Parliamentary Committees Act 1991, the Public Works Committee reports to parliament that it recommends the proposed project.

Mr TRELOAR (Flinders) (11:26): I, too, would like to contribute to the discussion today on the 554^th report of the Public Works Committee. I thank the committee for the opportunity to present to their most recent meeting, when they also took evidence from SA Water regarding the Tod River Dam upgrade.

This has not been without its concerns within the local community. We have had the opportunity—through some rather belated public consultation from SA Water and also through the opportunity for me to present to the committee—to raise some of these issues. To SA Water's credit, they have listened broadly to what the community has had to say about this, and their concerns, in the first instance at least, that were that there was very little public consultation with regard to this works program.

The member for Elder has very succinctly described the history and the iconic status of the Tod Reservoir. At the risk of going over old ground, I would once again like to speak in the parliament about the status of this reservoir on Eyre Peninsula. It was built through the early 1920s and ultimately, along with the railway line, it aided a big part of the settlement of inland Eyre Peninsula. In its day, it was an extraordinary engineering feat before the days of mechanical bulldozers or excavators. Some steam-driven machinery would have been used, but essentially it was horse-drawn and men with picks and shovels.

To dig a dam which ultimately had a capacity of some 11.3 gigalitres in the early 1920s was an extraordinary feat. Even more extraordinary was that the water captured and held within the dam was pumped to the top of Knotts Hill, which is the high hill adjacent to the reservoir. From there, incredibly, it gravitated all the way to Ceduna—some 250 miles. It was the most remarkable engineering feat unsurpassed anywhere in the world. Even in America, they had not managed to do this—250 miles of gravity-fed water reticulation in the 1920s.

There were some holding tanks at Minnipa Hill, which added to the pressure on the second half of the journey. It was quite a feat and incredibly important. Ultimately, pumps were installed and that increased the efficiency of the system. Its gravity feed was up the map as well, which made it more extraordinary. The water went north. The member for Elder quite rightly pointed out that the reservoir has been offline since 2002 largely due to salinity issues. SA Water's obligation now is to provide potable water through their reticulation system.

Salinity was always an issue within this particular catchment. It was recognised from the very early days that salinity had to be actively managed. Over time, the salinity of the reservoir increased so that it no longer fell into the World Health Organisation and SA Water standards of 1,000 parts per million salinity as acceptable for drinking water. Of course, in the early days, it did not have to be potable water. It was purely and simply to stop water and primarily to run the trains up and down the peninsula.

I mentioned the fact that the locals were concerned about the lack of consultation initially. SA Water has addressed that. After some pressure and some demand, SA Water held two public meetings, both in Tumby Bay. Both were very well attended. I managed to get to one of them. The local government was involved, and some 60 to 80 people were at both meetings. They really wanted answers to some questions, particularly around the long-term future of the dam, the reservoir and also, as the member for Elder related, the long-term security for Eyre Peninsula.

This upgrade was never intended to address the water security issue on Eyre Peninsula. Obviously, SA Water has said that, but I can assure people that it remains at the top of the mind of the residents of Eyre Peninsula. Initially, when this project was announced some three years ago in the state budget figures, it was a significantly higher figure than the current $6.3 million. I for one was quite excited to hear that money was to be spent on the Tod River Reservoir on a dam bank upgrade because I thought, in my naiveté, that there would be a long-term use for the water in this iconic reservoir. It was not to be, however.

As has been stated in the report, the upgrade will merely ensure that the dam bank is safe to hold water at around 8 per cent of the dam's capacity. I think that is a waste of a useful resource, but that is my personal opinion. SA Water has assured us that there will be an opportunity in the future, should the demand occur, for further upgrades and for the capacity for the reservoir to be installed. Who knows what the future might bring? There might be water security issues that unfold quite quickly, and there could be demand from another customer. I know that there have certainly been talks between the government and a potential mining company about drawing water from the reservoir. We will see where that goes.

I will finish by saying that there is a certain amount of bemusement amongst the locals, particularly with regard to the ANCOLD demands. I understand that South Australia is a signatory to these dam safety requirements. In a nutshell, the ANCOLD requirements include that this dam bank is upgraded in order to withstand our one in 600,000-year flood event. I kid you not—one in 600,000 years. That is more than half a million.

Mr Pengilly: We'll probably still be here.

Mr TRELOAR: Well, I might be, Michael—you never know your luck—and the member for Schubert certainly will be. This is extraordinary, all this is in a catchment of some 40 square kilometres. That is all it is—a tiny catchment. As I indicated in my evidence to the committee, if I think about 600,000 years ago, that is BC, before modern humans even walked on this earth, so it is quite an extraordinary commitment by the South Australian government and almost defies common sense. I think far more of a risk than the safety issues downstream is the impact some of this work could have potentially, given that the water flows will be going by the dam on local government assets, crossings and the like.

There have been some concessions from SA Water. They have agreed to set up a reference committee and I congratulate them for that. I hope that the call for membership goes out soon. It will give the local community and local individuals the opportunity to be part of the discussion not just about this project but about works in the future and that ever present and ongoing water security issue.

The other concession we received from SA Water as a result of a meeting between myself, the Minister for Water, some local constituents and SA Water representatives was that they would more actively manage the salinity within the reservoir. They intend to do that by not just relying on the inflows of Toolillie Creek, which is the most saline of the three inflows, but by actively directing into the reservoir some water at least from Pillaworta Creek, which is of better quality, and in that way manage the salinity. When a small body of water is not actively managed, ultimately the salinity will become higher and higher, and the outcome is not good environmentally or practically in the long term.

I accept that the work is going to go ahead. I accept also that SA Water have made some concessions along the way with a somewhat belated effort at community consultation. I hope very sincerely that that consultation continues and, with the opportunity of setting up a reference group, I think that will be a very valuable chance for the local community to retain some ownership of what once was a very iconic public asset and one which the local community still feels very strongly about.

Mr PENGILLY (Finniss) (11:36): I listened with interest to the member for Flinders, as did the committee in the hearing a couple of weeks ago. It became pretty obvious pretty quickly that the Tod dam is a pretty iconic part of Eyre Peninsula. When I was going to school some decades ago, one of the things we learnt about was the geographical and infrastructure history of South Australia. In those days, we used to know the names of all the reservoirs and dams; indeed, the Tod River Dam was one of those that was discussed regularly.

I must admit that when I first read of the project of some $6.3 million to strengthen the wall of a dam that was not being used, I asked a few questions about why on earth we were going to do that. It was made pretty clear to us that it was in the best long-term interests of Eyre Peninsula to upgrade this wall. The one in 600,000-year flood really did not concern me too much. Quite frankly, if we got away with it this year with the high rainfall we have had, we are doing pretty well.

As the member for Flinders said, and as was expressed during the hearing, it may well have a future use, and I would like to see that that could happen. Indeed, in due course it could have a desalination plant on it; that is a use. It is a substantial volume of water. Given that Port Lincoln in particular is growing reasonably steadily and that water is a prerequisite for us—we cannot exist without water, shelter and food; they are the prerequisites for human existence—at sometime in the future that may well justify our keeping the body of water there.

I know that the member for Flinders is pretty passionate about it. I think SA Water had erred in doing consultation on this project prior to going out, but they have picked up their game and are now doing that consulting. They were not keen to admit it, but they did admit that perhaps they had not done it quite properly, and the member for Flinders has honoured them for that. We might have to go and look at it, member for Flinders. This project will be of benefit in the long term, so the opposition members have supported it.

Ms DIGANCE (Elder) (11:39): I would like to thank the member for Finniss and, in particular, the member for Flinders for their contribution to and support of the Tod River Dam upgrade. I recommend the report to the house.

Motion carried.