‘Daylighting’ – a novel approach bringing waterways back to life (podcast)
In the next in our series of podcasts, we look at a patch of grass in Melbourne suburbia, that has been transformed into a gurgling, bubbling, and flowing creek.
The Dandenong Creek runs through Melbourne's eastern and south eastern suburbs, but for decades sections have been buried below ground in stretches of pipe.
In Heathmont that's all changed, thanks to Melbourne Water's $14.5 million Enhancing Our Dandenong Creek Program. Today this stream is once again seeing daylight.
Sarah Watkins talks to Anthony Stewart about the Melbourne Water Enhancing Our Dandenong Creek Program.
Quest :Sarah Watkins, Melbourne Water
Anthony Stewart: In the midst of Melbourne suburbia, a patch of green grass is being transformed into a gurgling, bubbling, and flowing creek. The Dandenong Creek runs through Melbourne's eastern and south eastern suburbs, but for many years sections have been buried below ground in stretches of pipe.
Anthony Stewart: In Heathmont that's all changed, thanks to Melbourne Water's $14.5 million Enhancing Our Dandenong Creek Program.
Anthony Stewart: Today this stream is once again seeing daylight. Melbourne Water has created new billabongs, and flowing water that builds habitats for threatened fish, frogs, and birds. With thousands of native species planted the project is creating a rich, biodiverse environment, and a splendid park for locals to enjoy.
Anthony Stewart: Melbourne Water's senior planning engineer, Sarah Watkins, sat down with Anthony Stewart to explain why Melbourne Water is committed to enhancing Dandenong Creek.
Sarah Watkins: Well, Dandenong Creek is located in Melbourne's east. It's one of the five major caches of Melbourne Water's area. Dandenong Creek is actually the third most visited waterway in Melbourne's area. It's really popular for bike riding, dog walking, running, and that's because it's got great connectivity, and a beautiful open space that people to come and enjoy.
Sarah Watkins: It's not the same as some of the other creeks that we've got, like the Yarrow River, that sort of has platypus and other really iconic species, but it is still pretty special in terms of the species that live there. In particular, there's a lot of native fish that like to live in little billabongs, and wetlands that are along the creek. So it's certainly got a lot of plants and wildlife, but unfortunately Dandenong Creek has been pretty heavily modified over the last decades. It used to take a really windy, sinuous course through the landscape over the floodplains of Bayswater, but in the 1960s the Dandenong Valley Authority actually straightened, and did a lot of work to modify the creek to manage flooding in the area. Unfortunately it has had a bit of modification, but it certainly is still very dear to the hearts of the locals.
Anthony Stewart: What was the aim of the Enhancing Our Dandenong Creek Program?
Sarah Watkins: Really, the objectives were to provide habitat for threatened fish, focus on pollution prevention works, and really to increase the natural amenity of the creek.
Anthony Stewart: How was the community involved in the process?
Sarah Watkins: The community's been very heavily involved in this project, and that was really something that sets the Enhancing Our Dandenong Creek Project apart from other things that Melbourne Water has done. You know, as the water industry, we're really hearing that more and more that our customers want to be involved in decision making, and we really decided on this project to take leadership in this space, and actually invite the community in to that decision making conversation.
Sarah Watkins: What we did was we established a working group that had representatives from friends of groups, local members of the community, councils, other government agencies as well. Melbourne Water really handed over the reins to this working group and said, "What would you like us to do?" They said things like, "It's really important to us to be able to hear the open, flowing water. We want to be able to feel like we're immersed in a natural environment. You know, we visit the creek a lot, and we really want to have a rich experience when we visit the creek."
Sarah Watkins: The community came up with a broad range of options, and over the course of about 12 months and number of workshops we worked with them to refine those options down, and their two preferred options which the community group and the working group selected was actually to daylight a section of Dandenong Creek, and to also improve the billabongs in the area. Dandenong Creek used to have a lot of billabongs that are still evident in the landscape but certainly aren't really there anymore due to the modification works that have gone on, and land use changes in the area.
Anthony Stewart: Daylighting is an interesting term. I don't think anyone who knows what a creek is would think it needs to see daylight. What is that? Explain that to me.
Sarah Watkins: Well, actually around Melbourne a lot of the creeks that we have these days are actually underground. They've been turned into drains. And that's actually what happened to Dandenong Creek in the 1960s. What used to be an open, flowing waterway got piped and buried underground. What we do through daylighting is actually the process of uncovering that creek, and literally bringing the water back to see the daylight. What we did in the daylighting of Dandenong Creek Project was actually dig up the pipe section of creek, and reinstate an open, flowing waterway with natural banks, natural form, variation in the shape of the channel and the flowing course of the creek, and planting it back out with native vegetation as opposed to it being basically a concrete pipe in the ground.
Anthony Stewart: How did you go about doing that, removing the pipe and constructing this natural watercourse?
Sarah Watkins: Well, it took us quite a while. After the Natural Amenity Working Group decided on the option of daylighting, we got to work on looking at things like flood modelling, a lot of investigations to understand the stability of the soils. It's quite a big project, and I should say that daylighting of creeks isn't something that's really done by Melbourne Water or by other water authorities or waterway managers, really, around the world. It's quite a new and novel thing to do.
Sarah Watkins: One of the really important things about uncovering the creek and daylighting it is making sure that we're not increasing the flooding issues. We did quite a lot of investigative work to look at the flood modelling, and understanding that this project was feasible. That took us a little bit of time, probably around 12 months from inception, and we started construction early in December 2017.
Sarah Watkins: The construction took about six months. What we first did was remove the top layer of the soil, and then actually working from the downstream section and sort of working our way upstream. We would basically dig out all the soil, remove the pipe, create the natural creek form, and then move on to the next bit. We did it in a couple of stages working our way upstream along that 830 meter section. It was pretty impressive works, though. Like I said, it was not something we've done before, and that comes with challenges. You're working on a live waterway. You're working in areas that can be unstable because they're wet because of the ground.
Sarah Watkins: We did a really good job. It managed to finish on time. It managed to finish on budget. We actually removed 16,000 cubic meters of soil, which I haven't done the calculations to know how many Olympic sized swimming pools that is. I keep meaning to do that. We put in 27,000 plants as well, so it was pretty extensive works.
Anthony Stewart: Why was it so important for Melbourne Water to recreate a natural environment like this?
Sarah Watkins: The waterway is a pipe in the ground. It's not really providing much value to the community other than flood protection. But waterways have many other values. People enjoy going to those spaces because they enjoy seeing the water. They enjoyed hearing the water. They like walking along the path under shading trees. But waterways, of course, also provide not just these social values, but also ecological values. If it's a pipe, it's really hard for fish to migrate up and downstream. In Dandenong Creek, we've got eels. We've got a number of fish. We've got turtles, and the pipe can actually be a big barrier to these populations, and can really be quite a constriction in how far, and how well these sorts of species do in the area. Not only is the naturalized waterway, the daylighted creek, providing a huge improvement in terms of amenity value to the community, it's also providing a lot of ecological value as well. We've got great habitat. We've got logs where little bugs can live underneath, and the birds have just come in straight away.
Sarah Watkins: Basically, as soon as we opened it up, the birds just flocked to it. It's great now. People see it, and they can really enjoy, and the impact it's had on the community has been really, really huge, and every day that I go out there I hear people saying to me, "This is just fabulous! I'm so glad that you guys did this! I didn't even realize that I missed it as a waterway, but now that it's here I can't imagine what this place would be without it."
Anthony Stewart: One of the areas that you focused on was helping threatened fish and frog species. What did Melbourne Water do to achieve that?
Sarah Watkins: As I mentioned earlier, that this program of Enhancing Dandenong Creek actually had four projects, and one of those really was to focus on a native fish in the area called Dwarf Galaxias. Now, Dwarf Galaxias is a pretty cool little fish, because actually even though it's only about three of four centimetres long, it can air breathe. So most fish breathe underwater, right? But Dwarf Galaxias can actually breathe air if it's in mud. This is a survival mechanism because of, as we all know, the Australian climate is quite harsh. It comes with floods and droughts. Dwarf Galaxias has evolved, essentially, to be able to survive during droughts. It sits in these little ponds, and as the water level drops down, it might even turn to just basically a muddy bog, Dwarfies can actually ... We call them Dwarfies. Dwarfies will actually burrow down into the mud, and they can air breathe, and that enables them to survive for a couple of weeks until the next rains come.
Sarah Watkins: Dwarf Galaxias live actually in the billabongs, not in the creek itself, and through urbanization a lot of those billabongs have been cut off. They're great places to put houses. We've drained them because they're a bit mucky underfoot, and so poor Dwarf Galaxias have lost a lot of habitat. What we decided to do through this project was actually reinstate that habitat in the landscape, and you can see small depressions all along Dandenong Creek, which is actually the old watercourse. What we did there was we did some really small works to actually plant out some species, get some storm water through those systems as well, so we're doing storm water treatment from runoff from the residential areas, as well as creating habitat for these little Dwarf Galaxias fish, and we have successfully bred them up.
Sarah Watkins: We bred them up in a nursery site, and we've actually translocated 600 fish in April this year. Our monitoring is showing that we've actually doubled our population since then, so the Dwarfies are loving their new home, and that's been really successful. This fish hasn't been seen in this area for ... Along with the Yarrow Pygmy Perch, these fish haven't been seen for probably a couple of decades, so it's been a huge win for this project, and for the community, and especially for the Dwarfies to actually be a sustainable population along the creek again.
Anthony Stewart: So we've heard how it's been wonderful for animals, but obviously local residents sound like they're loving the changes that it's created?
Sarah Watkins: Absolutely. Recently we had a community planting day. We planted 3800 plants along the banks of the Dandenong Creek. I actually had one lady who came down with her one-year-old daughter, and they planted a little tree together in the creek bed, and they took a photo of it, and they called it Sophie's tree, and they're going to come back and watch that tree grow over time, and I think that's a really fabulous story to actually ... For this girl to be able to come by in five years time, in ten years time, be able to see that she has been part of that, and to actually see the creek growing and evolving in the same way as she grows over time.
Sarah Watkins: It's quite interesting, because when you're an engineer, and you're sitting in the office, and you're looking at plans you sort of think, "Oh, yeah. There's a few lines on a page, and I guess this is what it's going to look like." But actually getting out there, and seeing the rocks, and hearing the water flowing over the rocks, and the birds frolicking along the banks, it's just a totally different feeling, and it's just absolutely fabulous. It's a fantastic looking project. The community loves it. But I think we'll have to be doing a few more daylighting projects, because it's been pretty successful.
Anthony Stewart: Outside of daylighting the Dandenong Creek, you also created a whole range of new amenities for people who use the area. What did they include?
Sarah Watkins: The Natural Amenity Working Group suggested a revitalization of Dandenong Creek, and really some signage in the area they thought would be a really good addition. What we did was we engaged with a local history group, the Heathmont History Group. We uncovered this fantastic, rich history of the area. The whole area used to be orcharding space. It's really interesting, but the first champagne in Australia was bottled on the banks of Dandenong Creek.
Sarah Watkins: There's these fantastic stories about Hermann Busch, who built a weir, and he had a little dam there. He had a little tea shop, where he would have Devonshire tea, and people would stop there on their way out to the Dandenong on a weekend, and it was a real destination. There are these fascinating stories about the people that used to live along Dandenong Creek, and the quite a modern histories from the 1930s onwards that we just had no idea about. The Heathmont History Group were able to uncover a lot of that information, and we worked with them. They provided us with so much, some fantastic photos, and wonderful quotes, and we thought, "This is really something we want to share with the community."
Sarah Watkins: We actually developed up 15 signs that we've put in along Dandenong Creek. They cover off things about the European history. We've got some indigenous art that was done by Ash Firebrace, a local Wurundjeri artist. We've got some fantastic Dream Time stories. We've got interesting facts about the flora and fauna, about the frogs, about the billabongs that used to be along the creek and what lives there, and it really just creates that connection to space, so people get a real appreciation of where they're standing, what it looks like today, but actually try and imagine what this place used to be like when there was cherry trees, and peach trees, and the creek was running along the banks with eels jumping through it, and people were going down there to fish on the weekend, and stopping for Devonshire tea. It's a really interesting history of the area. It was certainly something we wanted to share, but it was a bit of an unexpected surprise for us, but one that I think has really added value to the project, and really created that connection to space, and certainly added to the amenity of the area.
Anthony Stewart: Sarah Watkins, thank you for your time.
Sarah Watkins: Thank you very much for having me!
Anthony Stewart: Why not take a day trip to see this extraordinary transformation at HE Parker Reserve in Heathmont? Or you can head to the Melbourne Water website: MelbourneWater.com.au, to get all the information on how Dandenong Creek is seeing daylight again.
Melbourne Water has created new billabongs, and flowing water that builds habitats for threatened fish, frogs, and birds. With thousands of native species planted the project is creating a rich, biodiverse environment, and a splendid park for locals to enjoy.
Senior Planning Engineer, Sarah Watkins, sat down with Anthony Stewart to explain why Melbourne Water is committed to enhancing Dandenong Creek.
For more information on the project visit: www.yoursay.melbournewater.com.au/enhancing-our-dandenong-creek/daylighting-dandenong-creek