Mulgowie Riverbank Restoration Program
The Lockyer Valley is ground zero for sediment pollution in South East Queensland. Since European settlement, the Lockyer Valley has been synonymous with farming and agricultural pursuits because of the region’s fertile lands and rich soils. As the region grew, increasing amounts of land and vegetation was cleared particularly along waterways like Laidley Creek. Trees and vegetation help stabilise creekbanks, and when cleared, the resilience of riverbanks and creekbanks is severely threatened. As a result, waterways like Laidley Creek became increasingly susceptible to erosion.
When major floodwaters strike the region, torrents of water wash away riverbanks, causing valuable topsoil, mud other pollutants to flow downstream. Ultimately, the soil and mud ends up in the Brisbane River and Moreton Bay, where it smothers seagrass and damages important marine habitats.
In the aftermath of the devastating 2011 and 2013 floods, research identified that the Lockyer Valley region was responsible for 80 per cent of the soil and mud (sediment) pollution found in the Brisbane River and Moreton Bay.
In response, Healthy Land and Water developed the $2.4m Mulgowie Riverbank Restoration Program in partnership with project funders Queensland Urban Utilities and Port of Brisbane. The project was designed to build resilience into a deeply eroded 3km section of Laidley Creek located close to Mulgowie Farming Company – a sustainable farming operation which relies on the retention of rich topsoils to grow a variety of produce.
A key aspect of the project was the collaboration between landholders and project leaders. Because much of the degraded riverbanks were situated on private land, project leaders forged strong relationships with landholders who agreed to relinquish portions of their land to ensure the restoration works were effective.
The restoration of the riverbank involved planting 20,000 trees and grasses, reinforcing creekbanks with rock chutes and other natural infrastructure, and installing flow reduction devices like pile fields.
The ongoing project is a testament to what can be achieved when landholders, industry, local government and community groups work together to protect and improve the natural assets of South East Queensland.
Mulgowie Riverbank Restoration Project Milestone 1
It is estimated the project prevents about 16,000 tonnes of sediment, 11 tonnes of nitrogen and 22 tonnes of phosphorous from drifting into the catchment every year.
That is the equivalent of keeping 1,280 standard-sized truckloads of soil out of South East Queensland waterways and Moreton Bay each year.