Doreen Sewer Odour Management Project
We are undertaking works to reduce the likelihood of sewer odours occurring in parts of Doreen.
Some customers in the area have been experiencing issues with sewer odours, and Yarra Valley Water is committed to resolving these issues as a priority.
What is causing the odours?
Sewer odours can occur for a number of reasons.
We’ve investigated the issue in Doreen, and have found that the odour being experienced in the Vaucluse Estate occurs because the existing sewerage system doesn’t have enough capacity to handle the amount of sewage flowing through it. As a result, the flows in the sewer pipes are more turbulent than they should be, stirring up the sewage, and these conditions are causing the odour.
Our approach to resolving odour issues
Identifying the cause of the odours, and finding the best solution to manage these odours, is complex. We’re a little while off implementing a long-term solution, yet have been applying other measures to reduce the likelihood odours in the meantime.
Our long-term solution
What we've done so far
Since becoming aware of the odour issue, we have applied the following short-term measures:
- Since July 2016, we’ve been dosing non-hazardous chemicals into the sewer pipe from a Sewage Pumping Station (SPS) located ‘upstream’ of where odours have been reported. This has reduced, but not fully prevented, the production of smelly gases.
- In July 2016, we installed two carbon filter units (that look like green domes) in Coolong Terrace and at the corner of Garden Road and Orchard Road. These units vent air from the sewer through a carbon filter, which removes gases from the sewer without releasing odours into the environment. We are regularly monitoring these filter units to ensure they are working correctly.
- Since February 2017, we have been maintaining the chemical dosing and carbon filter units more frequently, to ensure the equipment is operating as it should.
- In April 2017, we installed some electronic monitoring equipment into the sewer. This equipment will alert us to when odours are likely to occur, so we can act before the odours escape the sewer.
- In May 2017, we completed some targeted on-property odour investigations. This was done to better understand the nature of the odour issues that are being experienced by some customers, so we can identify the most appropriate solution.
- In June, we reviewed the data from our odour monitors and identified improvements we could make to our nearby chemical dosing facility. These improvements could be made within a month's time.
What we're doing now
We’ve experienced a few reliability issues with our chemical dosing system in recent months, and will be replacing it with a more reliable system in early July. We’ll also bring our air quality monitoring expert back to confirm that the new system is operating as it should be.
We continue to regularly visit the areas where odours have been reported. Our electronic monitoring equipment installed within the sewer will alert us when odours are likely to occur, giving us a chance to act before they become noticeable to anyone in the area.
Despite these measures, we’re aware there are still some sewer odours in the area, and are committed to resolving the issue by providing a long-term solution.
How we'll fix the issue
We have now identified the most suitable long-term solution, which we are confident will reduce the sewer capacity issues currently being experienced in the local area, and the broader area in Doreen.
The solution involves building a new section of underground sewer pipe near Painted Hills Road, Doreen (close to Laurimar Lake) to divert sewage flows into the larger sewer pipe that exists there. This means that the sewerage system in Doreen will no longer be operating beyond its capacity, and the likelihood of odours being caused by turbulent sewage flows will be greatly reduced.
Construction activities to build this new 300-metre-long section of sewer will begin shortly, and are scheduled to be completed by September 2017, subject to good weather and ground conditions.
When completed, there should no longer be any noticeable smelly odours from the sewer.
Please tell us if you notice sewer odours
For Yarra Valley Water to provide the most effective solution to odours in your neighbourhood, it would be useful for us to know the time, date, and location of odours as soon as they occur.