The Rowan Swamp restoration trial is getting a serious work-out!
In the Goulburn Valley (in northern Victoria near Benalla and Shepparton) it has been a very steady late winter and early spring for rainfall, which is giving the new Rowan Swamp restoration trial structure a real work-out!
As we reported last month, we had literally only just completed the structure when the catchment flows arrived a short time later. With more rainfall events since, and more predicted over the coming weeks, it is going to be fascinating to see how the wetland responds this spring and summer.
In a recent visit, a surge in inflows after recent rainfall a few days earlier had caused the wetland to temporarily surcharge about 30cm above the cease-to-flow (CTF) level set at the new restoration trial structure. Levels were dropping again at the time of my visit, noting that the peak flow at this location arrives quickly given the flashy nature of the local Boosey Creek catchment. Because this is an instream floodplain wetland, and the trial structure is located within the eroded creek bed at the former edge of the swamp, the capacity to pass flows increases greatly when water levels surge higher than the structure’s CTF level.
If you look closely at the second image below, you will see where water is spilling both over and around the trial structure, as intended, corresponding with the big increase in flows since August.
For a birds eye view of how site conditions have changed, before and after the trial structure was installed in July, as well as images from August and September, please click through the pdf slides below. As you will see, it is wet out there!Above-view-2
In terms of the impact of the trial in attenuating flows and ultimately allowing Rowan Swamp to retain water longer as inflows recede, everything is so far working as we hoped. Inundation during moderate flows has now also been demonstrated to be contained within the footprint predicted during the planning phase for this project, based on the LiDAR elevation data, and as discussed with the local community and neighbours. Meanwhile, the wetland flora and fauna are about to explode to life with the warmer spring weather on the way. Stay tuned, as we’ll have more to report as this project progresses…
But for now, enjoy the magnificent latest view of a full Rowan Swamp!
This project is supported by Nature Glenelg Trust, through funding from the Australian Government’s Murray–Darling Healthy Rivers Program and Parks Victoria.