“We don’t sit outside anymore” say residents fearing health issues from Lower Vasse River water quality

Residents living along the Lower Vasse River say they are concerned with harmful cyanobacteria in the waterway, with one couple avoiding their own backyard because of it. Jill Walsh and Dr Andrew Dickie, whose property backs onto the river, said they were unaware of ongoing water quality issues when they bought their home. “We had a neighbour knock on our door and tell us about the condition of the river,” Ms Walsh said. “I remember thinking, ‘what’s wrong with it?’ I thought it looked pretty.” Now, she said, they no longer sit outside near the riverbank. Dr Dickie, who has a background in microbiology and pathology, said his main worry was exposure to cyanotoxins produced by certain types of cyanobacteria. “The one I’m most concerned about is a long-acting cyanotoxin called BMAA,” he said. “The way BMAA works is you either consume it in water, fish or shellfish from the river and it can accumulate in the body and affect the brain. “You can also breathe it in, which is the worst one, the one I’m worried about.” The Federal Government’s Water Quality Australia program claims cyanobacterial blooms lead to deterioration of water quality and production of toxins by some species. Exposure to algal toxins has been linked to fatalities of livestock, wildlife and pets. Vasse MLA Libby Mettam said more needed to be done to improve the health of the river. “A lack of funding and downgrading of the Vasse Taskforce, formed by the previous Liberal-National government to improve the overall wetlands systems, have compounded the issues with the dire state of the Vasse River,” she said. “Further, the City of Busselton are challenged by a complex management structure of several State Government agencies that oversee the project.” Water and South West Minister Don Punch said the Cook Government recently committed $2.31 million through its Healthy Estuaries WA program to specifically improve water quality in the Vasse-Geographe waterways. “The challenges facing the Lower Vasse River stem from long-term environmental pressures such as high nutrient loads, low flows and warm summer conditions, rather than any reduction in government support,” he said. “The Vasse Taskforce and its partners continue active, science-driven work to reduce nutrient levels entering the river through fertiliser reduction programs, catchment management, and in-river treatment trials under the Healthy Estuaries WA program.” Mr Punch said a recent project carried out by the taskforce was sediment reduction works along the shoreline, completed in 2024, which is already helping to improve conditions. “Recognising the importance of strong leadership, I also appointed a new independent chair, the highly experienced Ms Neema Premji, last year, whose role is to maintain momentum across all partner agencies,” he said. “Ms Premji is a civil engineer with more than 25 years of experience across infrastructure, utilities, mining and government trading enterprises, and has expertise in financial and asset management, strategic planning and corporate governance.” A fish kill in the Lower Vasse River in January was most likely caused by very low dissolved oxygen levels in the water, a Department of Water and Environmental Regulation spokesperson said. “Data from a monitoring logger shows that oxygen levels dropped to near zero for extended periods in the days prior to the reported incident,” the spokesperson said. “A dense blue-green algal bloom (cyanobacteria) was present, but acute fish kills are more commonly linked to oxygen depletion rather than toxin exposure alone. “Based on current information, no further response is required, however monitoring will continue.” The DWER spokesperson said there was no current indication of broader impacts elsewhere in the Vasse River relating to the fish kill. “Similar low-oxygen events can occur in slow-moving waterways during warmer conditions, particularly where algal growth is high,” they said. “DWER continues monitoring and will respond if conditions deteriorate or further incidents occur.” Since 2022, water quality monitoring in the Vasse River has continued, including tracking algal composition and concentrations, dissolved oxygen and temperature. GeoCatch, which has worked to improve water quality in the Lower Vasse River since 1997, said excess nutrients entering the river were the primary cause of algal blooms. “Our current focus is working with the community to reduce nutrients entering the river from the rural and urban catchments through projects such as reducing fertiliser run-off from farms and urban gardens and fencing and revegetating waterways,” a spokesperson said. “GeoCatch is also a member of the Vasse Taskforce who oversee management of waterways and water quality across the Geographe catchment.”