Parliamentary Committees

Public Works Committee: Happy Valley Water Treatment Plant Upgrade

Mr CREGAN (Kavel) (11:03): I move:

That the 102^nd report of the committee for the Fifty-Fourth Parliament, entitled Happy Valley Water Treatment Plant Health Compliance Upgrade, be noted.

The Happy Valley water treatment plant provides treated water to approximately 450,000 customers in central and southern Adelaide. SA Water has proposed to install an ultraviolet (UV) disinfection system to the existing water treatment plant at the reservoir. The proposed UV disinfection system will provide a pathogen barrier for water treatment.

On 23 July 2020, the Public Works Committee held a hearing for this project by videoconference and took evidence from SA Water officers. The proposed health compliance upgrade is part of SA Water's broader water quality improvement program, which will deliver new infrastructure and upgrades at the Happy Valley wastewater treatment plant. The project is expected to provide improvements in water aesthetics, odour and taste, as well as address potential water quality risks that are associated with the future opening of the Happy Valley Reservoir for recreational use this year.

One of the key outcomes of the proposed project is to reduce the public health risk of pathogen cryptosporidium breakthrough at the treatment plant. The estimated total capital cost of the proposal is $21.4 million. Practical project completion for the health compliance upgrade is anticipated to have occurred earlier this year.

The committee is satisfied that the proposal has been subject to the appropriate agency consultation and meets the criteria for the examination of projects described in the Parliamentary Committees Act 1991. Based on the evidence considered and pursuant to section 12C of the Parliament Committees Act 1991, the Public Works Committee reports to parliament that it recommends the scope of the proposed public works that I have described to the house.

Mr MURRAY (Davenport) (11:05): I rise to briefly note and endorse the Public Works Committee's recommendation insofar as the broader upgrade of the Happy Valley water treatment plant is concerned and, in particular, that which is before us which is part of a broader water quality improvement program, that being the health compliance upgrade.

The Happy Valley water treatment plant serves approximately 450,000 customers in central and southern Adelaide. It treats water for anywhere between 50 and 60 per cent of Adelaide and, as a result, it has a fundamental role in providing high-quality water to a substantial part of Adelaide. As I noted, this particular upgrade is part of a broader water quality improvement project that has been undertaken by the government and it represents a substantial increase in the quality of the water, as well as the general aesthetics of the water, including odour and taste.

What is not generally appreciated is that the water in question is often the subject of treatment to eradicate things such as algal blooms, which as a consequence can have some deleterious effects insofar as odour and/or taste are concerned. Notwithstanding that, the water produced by Happy Valley is of the highest standard.

However, there is one thing the current treatment works cannot address, as the member for Kavel has pointed out, and that is the possibility of cryptosporidium outbreaks. Cryptosporidium is a waterborne pathogen and the best way to eradicate or treat water to ensure there are no cryptosporidium outbreaks is to disinfect it—in this case, in particular, using ultraviolet light.

The evidence we have received is that there have been cryptosporidium outbreaks in the past in some of our reservoirs that have been treated and/or dealt with by SA Water. In particular, those outbreaks were in reservoirs that were not—I repeat, not—open to the public. This is a general issue insofar as water provision and water quality are concerned. The key thing is that there has been a long-term desire on the part of SA Water to increase the degree of safety and treatment by virtue of installing UV.

As a consequence or as a by-product of the opening of Happy Valley Reservoir for use by the public, we have been able to bring forward this incremental improvement in the safety of the water supply to 60 per cent of Adelaide by the installation of the UV disinfectant treatment. As the member for Kavel has pointed out, $21.4 million is the overall spend and, as I said, this is part of a broader, bigger spend to improve not just the water quality and safety but also the water's aesthetics, such as odour and taste, etc.

I point out that Happy Valley Reservoir is additionally a considerable way progressed in moving the majority, if not all, of the treatment plant from traditional power sources to one being supplied via onsite solar energy. SA Water is a leader as far as that process is concerned at many of its sites, Happy Valley chief amongst them. One of the things that has flowed from that is that the initial intention was to install UV, albeit utilising pumps, at a lower capital cost than the $21 million. However, for those who are interested in engineering matters of this ilk, for a larger capital cost, the $21 million, there will be far lower operating costs as a result of the UV plant being gravity based, gravity fed, rather than using traditional pumps.

The bottom line is that we will get safer water sooner at Happy Valley and for its customers—who, as I said, comprise, roughly speaking, anywhere up to 60 per cent of the Adelaide metropolitan area—as a result of a broader suite of expenditure designed to improve the outcome of the water quality, the water aesthetics, at Happy Valley. On that basis, I heartily commend the project to the house.

Mr CREGAN (Kavel) (11:11): I acknowledge the contribution made by the member for Davenport and also his commitment, passion and diligence when it comes to local matters. He is also of course the deputy presiding member of the committee. We commend the project to the house.

Motion carried.