Grampians wetlands – where are we at with water levels?

Grampians wetlands – where are we at with water levels?

In a short few years NGT has managed to secure and make big steps towards restoring two amazing wetlands of the Grampians region – Walker Swamp Restoration Reserve and Green Swamp Restoration Reserve.

This time last year we were witnessing the first arrival of inflows to Walker Swamp since its full restoration. As we now know, those inflows were fairly short-lived and failed to fill the wetland to its newly restored capacity. So twelve months on we thought we’d have another look and see how we are tracking this year. Despite the hot summer, the wetland retained water throughout the year, probably for the first time since the drains were dug, and didn’t drop below the levels we saw prior to inflows last year. The low winter rainfall, and absence of any inflows, means that levels are sitting below those recorded at the same time last year.

Water level and rainfall at Walker Swamp from winter 2019 to winter 2020
Comparing water levels from 29 July 2019 (left) and 13 August 2020 (right).

Over at Green Swamp, the true nature of this dry winter is very apparent. After drying down rapidly during a hot January, the wetland is experiencing the longest dry-phase since filling for the first time in 2016. In fact the water level in August was similar to February, which is a real contrast to the past few years. I should note that there was still a small puddle of water through Autumn in the deeper parts and we have recently moved our logger so we can measure levels at the deepest point of the wetland, which is about 20 cm below where the logger has been up until now. This deeper area also features as a refuge during drier years like this, as reported by Greg earlier this year.

Rainfall and water levels at Green Swamp over the past four years
Green Swamp water levels at the logging station in Februrary 2020

So things look a bit grim for wetlands this year but the BOM long-term forecast looks promising, and the chances of a wet spring are about as good as it gets. So let’s hope we see some inflows over the coming months, and with that, another year of these sites providing summer refuge for our local wetland fauna.

Lachlan Farrington