It was our last morning in Wagga Wagga and we were all so excited to hit the one city we’ve all been waiting for… Sydney! Of course, you’ve got to give up something great to get something great, and by this I mean it was time to say goodbye to our beloved Flick! It was so nice to meet you, Flick! We all wish you safe travels home and want to thank you so much! We ate our last delicious breakfast and headed on our way.
We started off our day at the Riverina Water County Council where Leanne Hastings was kind enough to show us around. She told us that the RWCC is located on the Murray-Darling basin and that the treatment plant supplies 16,000 square km and 65,000 people with potable water. As a food scientist, I was so excited to get back into chemistry and talk about something that I completely understand. We were off to see the treatment process.
Leanne explained to us that the water comes from two different places, bore (well/aquifer water) and surface water. I’ll start explaining the treatment process first with bore water. The aquifer water is pumped from a well that is about 70m deep below the ground surface. The water is pumped from the well to a holding tank located above ground, where the water is then aerated. The water is aerated to remove hydrogen sulfide and carbon dioxide gases. If the carbon dioxide is not aerated from the water, it could be corrosive to metals and end up ruining pipes that the water runs through. This water will later be combined with the surface water.
To treat the river (surface) water, the pH must first be corrected. The goal pH for water is between 6.5-8.1 seeing as a pH of 7 would be completely neutral. We correct this by adding lime to the water which raises the pH level (pH of water would never need to be lowered/made more acidic). Then, the water goes through a clarification process. This is done by adding a coagulant, Aluminum Sulfate, which gets the non-water particles to clump together and drop out of the solution into a tank beneath it. At this point, the bore water is joined with the surface water (70% bore, 30% surface).
The combination water is then filtered in a cylinder tank which keeps the untreated water in the center section and the treated water on the outside layer (see picture). The water in the middle section gets purified because the sludge is denser than the water, so the water gets pulled into the outer layer, while the sludge falls to the bottom and into holding tanks. Finally, the water is chlorinated and fluorinated and is held in covered tanks and ready for usage! It was a pretty cool and simple process.
South Australia has faced long periods of drought, leaving them with a shortage of water and the need to conserve it. Since the RWCC is in charge of so much water they have the major responsibility of conserving it. This must be done using sustainable methods. For example, to reduce evaporation and increase efficiency the RWCC has replaced some old piping. Also, the RWCC dehydrates their left over sludge and returns the water from that process to the Marshall’s Creek which keeps water in circulation. They also have taken to banning pumping from 10am-5pm because energy costs more to use in that time frame.
I personally was most impressed with the nature strip program they had recently launched. Leanne told us all about how 50% of the potable water from the RWCC is used by Wagga Wagga citizens for gardening purposes. This number shocked everyone, including the RWCC so they launched the nature strip program. This program gives a rebate to citizens who replace the lawn in-between their sidewalk and the street with drought-resistant plants. This reduces the need for water on lawns and, in turn, allows the water to be used for more important purposes. It was good to see that the main company in charge of water distribution has their own rules/regulations, especially since I’ve seen first-hand how precious water is to so many people in Australia.
After the water visit, we all hopped on the bus and went to the Country Link Train Station where we got on the train and began our trip to Sydney! Trying to be the straight A students we are at heart, we all used the four-hour train ride to complete, or begin ;), our next papers so that we have plenty of free time during our next few days in Sydney.
We got off of the train, checked in at the youth hostel, and went out to explore the city! Now it’s time to rest up and pick our teams for tomorrow’s scavenger hunt. GAME ON!!
The RWCC’s official website. Here you can find information regarding the goals and current projects of the RWCC. Also, they have made it easy to see how the community is involved and some water saving tips to help you reduce your water footprint.
This is a link that discusses adding lime to water for neutralization. There are certain advantages and disadvantages to the process. It also discusses returning the sludge to water systems after the clarification process. The link is a study to show advantages, disadvantages, and areas for improvement to all of these processes.
This link discusses several ways that the average consumer can reduce their water usage. The site breaks down water tips into categories of kitchen, laundry, bathroom, and garden. Also, information on recycled water and other water services are available on this link.
This link is the Australian drinking water guidelines. The website is a summary page and there is a PDF at the bottom for a complete list of guidelines that the RWCC must follow.
A little bit of background information of the Country Link train that we took from Wagga Wagga to Sydney.
Visit to the RWCC
Ride on country link train