Port Fairy ocean water monitoring trial
The results of a 12-month ocean water quality program show that Port Fairy is a safe place to swim. Wannon Water and Moyne Shire Council partnered in the trial where water samples were collected and tested for bacteria to provide information on the level of water pollution at beaches.
The issue
The trial aimed to increase public confidence following a number of ocean water quality events in 2021 when a brown substance was observed in the waters off Port Fairy.
At the time, the Port Fairy Sewage Treatment Plant was operating normally and had no adverse issues and that remains the case today. The system is doing exactly what it was designed for – to protect public health and the environment.
The detail
The project measured the impact of heavy rainfall, stormwater flows, high tides and algal blooms on water quality between December 2021 and November 2022.
The program was based on the Environment Protection Authority’s monitoring program for Port Phillip Bay and aimed to provide community-focused water quality information for swimmers and other recreational users. Samples were taken fortnightly during the peak summer period and monthly at other times.
Five beaches popular with swimmers and surfers – Golfies, East Beach, The Passage, South Beach and Pea Soup – were included in the trial.
All returned a rating of either ‘good’ or ‘very good’ water quality, indicating water quality was safe for swimming, except for one grading of ‘fair’ at East Beach following intense rain in early September. A ‘fair’ grading indicates that water quality may not be suitable for swimming and beach users should check for signs of pollution before they swim, and this information was relayed via the shire’s website.
The ’fair’ result was likely the result of stormwater or catchment run-off into the Moyne River and onto the beaches. The monitoring program showed that water with any elevated pathogen levels following stormwater pollution quickly returned to a grading of ‘very good’.
Samples were also taken at the mouth of the Moyne River, the edge of the ocean outfall mixing zone where treated wastewater is released, and at stormwater outlets if they were flowing.
Samples taken from the river mouth were all rated as “good”, except for those taken in early September after the rain event when the result was “poor”, indicating that the water quality was probably not suitable for swimming.
A stormwater drain at Ocean Drive was sampled after heavy rain in January, July and September, returning results of ‘fair’ each time.
We were already taking monthly samples at the edge of the Port Fairy ocean outfall mixing zone where treated wastewater is released. Additional shoreline samples were collected as part of the trial to compare to the beach sampling data. The samples collected from the edge of the mixing zone all graded in the ‘good’ and ‘very good’ category, except for a sample collected in early September, again following the intense rainfall. This sample returned a category of ‘fair’.
Benefits
The initiative aimed to increase public confidence following a number of ocean water quality events in early 2021 when a brown substance was observed in the waters off Port Fairy.
The project also helped to educate the Port Fairy community about how the town’s sewage treatment system actually works and the measures we have in place to protect public health and the environment.
Port Fairy
