Saturday, June 09, 2007

Goulburn Water Group Plan

The Goulburn Water Group (GWG) is a community group established to examine and discuss water management in their city. As it states on their website, the GWG “is an open forum to gather ideas and facts and focus community discussion on Goulburn’s water problems and solutions. Informed and balanced opinion is needed to achieve a sustainable solution.”

It’s no secret that a significant impetus for the formation of the GWG, was a proposal initiated by Goulburn-Mulwaree Council to consider the use of indirect potable water recycling. We gave some discussion to that plan on this blog a year ago. At that time, the National Water Commission had recently granted $50,000 to assist the City Council to undertake a community consultation process to inform the community and gauge support.

I went along to one of the council-organised community meetings in February this year. At that meeting, a range of potential approaches for improved water management were discussed. These included evaporation control for dams, long pipelines from the Wingacarribee Reservoir, non-potable water recycling and indirect potable water recycling.

This week, the GWG took the initiative to release its own proposed plan for Goulburn. The approach was “to identify and prioritise many old and new ideas and blend some of these into one integrated local, permanent, sustainable water plan”.

Accordingly, a broad range of water management ideas are discussed. These include improved stormwater use, refined demand management, improved ability to capture and store extreme (flood) river flows, water storage evaporation control, and the expanded use of rainwater tanks. However, the plans of most interest and relevance to this blog, are GWG’s approach to municipal water recycling. On the topic of recycled water, the GWG plan states:

“The plant at the northern end of the City currently produces treated effluent for limited reuse. ‘Polished’ recycled water could be produced to a suitable standard for unlimited reuse by industry, parks, gardens, irrigation and most importantly environmental flows in the Wollondilly River upstream of the City. The Copford Reach pipeline could recycle water from the sewage treatment and polishing plant back to the top of Marsden Weir. Also recycled water could be piped back parallel with the Mulwaree River to fields and the Goulburn Golf Course. Standpipes along the way could dispense the recycled water for business, building and construction work. Branch lines could bring the recycled water further into the City to Belmore Park. Then the Gaol, North Park, Tully Park and the Police Academy. Around the City sewage pumping stations, particularly in new subdivisions, could be mined with bolt on reuse plants for neighbourhood reuse.”

In other words, the GWG proposes to pipe reclaimed water from an upgraded treatment plant downstream of the city, back upstream. Along the way, the water could be accessed for non-potable uses, thereby off-setting potable water demand.

Of course, it’s important to recognise that under the harsh water restrictions currently imposed in Goulburn, there is very little outdoor irrigation use of potable water, so it will be difficult to make significant savings. However, it is a fair argument that the community would benefit by having the means to irrigate some areas even during severe droughts. Whether specific applications such as the Goulburn Golf Course would be considered to be a suitably high priority for limited water resources, would be a matter for the community (not me!) to discuss.

In addition to these city-based non-potable uses, the GWG plan proposes to use reclaimed effluent to enhance environmental flows in the Wollondilly River. The reclaimed effluent would be returned to the river at a point below the city’s drinking water extraction point (normally Rossi Weir). Although it does not appear to be clearly described in the currently available information, I assume that the impetus for returning environmental flows to the river is so that this volume might be re-credited back to the city’s extraction licence.

This concept of “effluent return” credits, may have potential to be useful to Goulburn as a long term strategy. It may allow the city to extract and store increased volumes of water at times when it is available. However, I have previously taken a quick look at this strategy for Goulburn myself. The information that I received from the City Council was that there currently are practically no environmental flows of potable water supplies released from Rossi Weir. Thus there is barely anything available to be saved by effluent return credits under the current conditions.

Or to put it in volume terms, Goulburn currently has a licence to extract up to 5000 ML of water per year. The city tends to take as much of this as is environmentally available in any year. During dry periods, there is practically nothing left over for environmental flows.

So, returning well-treated effluent to the Wollondilly River for environmental flow has an obvious potential for environmental benefit. For this reason, I applaud the concept. However, how it can be expected to contribute to water availability for Goulburn City during the times when it is most needed is not currently clear.

I recognise that there are lots of other good ideas in the GWG plan and that I have focused on only a very limited aspect. You can find further details here and I would be interested to discuss all aspects of the plan if people are interested to raise specific issues.


Anonymous said...

Goulburn does not need to recycle sewage water for drinking and neither does any other city. Australia has plenty of rain (take a look out the window!!). We simply need to build more dams to capture it instead of letting it all run out to the sea. Yes, it really is that simple!!!

Recycling sewage for drinking is just a money-making exercise for multinational corporations. Its about time the lie of Australia running out of water was exposed once and for all.

Stuart Khan said...

Thanks for your comments Anonymous,

I agree that dams are a very important means of supplying water for Australian cities. I’d be interested to know which additional waterway(s) you feel should be dammed to increase Goulburn’s water supply.

Alicia said...

Dams stop environmental flows and flood natural habitats and farmlands. Have a look at the proposed Tillerga dam by Hunter Water and all the controversy its caused. People don't want dams. Recycling to at least maintain natural flows seems like an innovative and good idea. Once people get over the 'yuk factor' of recycled water and understand their normal water is recycled anyway. Recycling sewerage is probably the best option.

Anonymous said...

i like turtles

Anonymous said...

im recycled water and i find this offensive

Anonymous said...

i was thinking of getting a bor but it would be boring!

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