Written in Collaboration with DCG Plumbing
A septic to sewer connection is the process of converting a property that currently uses a septic tank system so that wastewater flows into the public sewer network instead. Instead of wastewater being treated onsite through a septic tank and absorption trenches, it is redirected into the sewer system where it is transported to a treatment facility.
Across the Mornington Peninsula, many homes were originally built with septic tanks because sewer infrastructure was not available when those areas were first developed. As sewer networks have expanded over time, more properties have become eligible to connect to sewer systems managed by South East Water.
Once a sewer connection point has been installed on the property, a licensed plumber can connect the home’s drainage system to the sewer network. This usually involves installing a new sewer drain, pressure testing the pipework, and safely decommissioning the existing septic tank.
In many cases, once the connection point exists, the plumbing work required to connect the house itself can be completed within a single day.
Key Takeaways
• A septic to sewer connection converts a home from using a septic tank to using the public sewer network.
• Many homes on the Mornington Peninsula were originally built with septic systems and are now becoming eligible for sewer connections.
• The water authority installs the sewer connection point, while a licensed plumber connects the house drainage system to that point.
• New sewer pipework must be pressure tested before it is backfilled.
• The existing septic tank must be pumped out and properly decommissioned.
• Once connected, wastewater flows directly into the sewer network instead of being treated onsite.
• In many cases the plumbing connection work itself can be completed within a single day.
Why Many Homes Are Moving From Septic to Sewer
Septic systems have worked well for many homes for decades, particularly in coastal or semi-rural areas where sewer infrastructure didn’t exist at the time of development.
However, as communities grow and environmental standards evolve, more areas are transitioning to central sewer systems.
Homeowners often choose to connect to sewer for several reasons.
Environmental protection
Septic systems rely on soil absorption to treat wastewater. In sandy soils, which are common across the peninsula, wastewater can sometimes move through the ground faster than expected.
Sewer connections remove this risk because wastewater is transported to treatment facilities designed specifically to process it.
Lower long-term maintenance
Septic systems typically require ongoing attention.
Common maintenance tasks include:
• periodic pumping of the tank
• monitoring absorption trenches
• managing blockages or system failures
Sewer connections eliminate most of these responsibilities.
Property value and buyer preference
Many buyers prefer properties connected to sewer infrastructure. In some areas, properties may even be required to connect when major renovations or redevelopment occurs.
Why So Many Mornington Peninsula Homes Have Septic Systems
The Mornington Peninsula has a long history of homes relying on septic systems.
When many coastal suburbs were first developed decades ago, sewer infrastructure had not yet reached those areas. Septic tanks were therefore the only practical wastewater solution for many properties.
As the region has grown, infrastructure has gradually expanded. Water authorities have progressively rolled out sewer networks across various suburbs, meaning properties that once relied on septic tanks are now eligible to connect.
This transition is happening suburb by suburb as infrastructure upgrades occur.
For homeowners, the first indication often comes when they receive notification from South East Water advising that their property can now connect to the sewer network.
How the Septic to Sewer Connection Process Works
Although every property is different, the overall process of connecting a septic system to sewer tends to follow a similar structure.
1. Confirming eligibility
The first step is determining whether the property can connect to sewer.
This usually involves:
• contacting the water authority
• confirming infrastructure availability
• organising a site assessment if required
2. Installing the sewer connection point
If the property is eligible, the water authority installs a sewer connection point.
Depending on the area, this may include:
• a sewer pit
• a pump station
• a low-pressure sewer connection
This connection point forms the link between the property and the wider sewer network.
3. Connecting the house drainage system
Once the connection point is installed, a licensed plumber can connect the home’s drainage system.
This stage may involve:
• installing a new sewer drain
• modifying existing drainage
• trench excavation across the yard
4. Pressure testing the sewer line
Before the pipe is backfilled, the drainage system must undergo pressure testing.
This ensures:
• pipe joints are sealed
• wastewater will not leak into the soil
• the installation meets plumbing regulations
5. Decommissioning the septic tank
Once the house is connected to sewer, the septic system must be safely taken out of service.
This involves pumping out the tank and properly decommissioning it.
A Recent Septic to Sewer Connection in Capel Sound
Septic to sewer conversions are becoming increasingly common across the peninsula as infrastructure expands.
The video below shows a recent septic to sewer connection completed in Capel Sound.
The project demonstrates the typical process involved when a property becomes eligible to connect to sewer, including drainage installation and septic tank decommissioning.
The conversion shown in this video was completed by local contractor DCG Plumbing, who regularly carries out septic to sewer connections across the Mornington Peninsula.
What Happens to the Old Septic Tank?
Once a property is connected to sewer, the existing septic system must be properly decommissioned.
This prevents the tank from being used again and ensures it does not pose a structural risk underground.
The process usually involves several steps.
Pumping out the tank
A waste contractor removes all wastewater and sludge from the septic tank.
Cleaning the system
The tank is flushed to remove any remaining waste material.
Decommissioning the structure
The exact method depends on the type of septic tank.
Concrete tanks
Often have a hole created in the bottom so groundwater can pass through the structure.
Plastic tanks
Are usually filled with sand or soil to prevent the tank collapsing underground.
Backfilling
The tank is filled and sealed so it can no longer function as a wastewater system.
How Long Does a Septic to Sewer Conversion Take?
The overall timeline for connecting to sewer can vary depending on several factors.
The biggest variable is often the installation of the sewer connection point by the water authority.
However, once that connection point exists, the plumbing work itself is typically straightforward.
In many cases the process looks like this:
1. Sewer connection point installed
2. Plumbing work scheduled
3. Drainage pipe installed and tested
4. Septic tank decommissioned
For many homes, the plumbing connection work itself can be completed within a single day.
Larger properties or more complex drainage layouts may take longer.
What Does It Cost to Connect to Sewer?
The cost of connecting a property to sewer varies depending on the property layout and installation requirements.
Several factors influence pricing, including:
• distance between the house and the sewer connection point
• excavation requirements
• drainage modifications
• septic tank decommissioning
The water authority typically charges a connection fee for installing the connection point.
In some cases, homeowners may be able to spread these costs across their water bills over time.
The plumbing work required to connect the property is usually quoted separately by a licensed plumber.
Compliance and Plumbing Regulations
All septic to sewer conversions must comply with plumbing regulations in Victoria.
Licensed plumbers must issue a compliance certificate confirming that the installation meets the required standards.
This includes verifying that:
• drainage pipework has been installed correctly
• sewer pressure testing has been completed
• the system meets plumbing regulations
The process is overseen by the Victorian Building Authority.
Inspections may occur randomly during installation to confirm that the work complies with regulatory requirements.
Once certification is issued, the connection is officially complete.
Life After Connecting to Sewer
One of the biggest benefits of connecting to sewer is simplicity.
Once the conversion is complete:
• wastewater flows directly to the sewer network
• septic tank maintenance is no longer required
• absorption trenches are no longer used
For properties with sewer pump systems, the pump equipment is typically maintained by the water authority.
If issues occur, homeowners can simply contact the authority and they will organise repairs.
Final Thoughts on Septic to Sewer Connections
As sewer infrastructure continues expanding across the Mornington Peninsula, septic to sewer conversions are becoming increasingly common.
For many homeowners, connecting to sewer provides a more reliable and lower-maintenance wastewater solution compared to traditional septic systems.
While the process involves several steps including approvals, drainage installation, and septic tank decommissioning, the actual plumbing work is usually quite straightforward once the sewer connection point is available.
If your property has recently become eligible to connect to sewer, speaking with a plumber experienced in septic to sewer conversions can help ensure the process runs smoothly from start to finish.
Other Posts in relation to Sewer Drainage
- What is an Overflow Relief Gully
- 10 Common Causes of Blocked Drains and How to fix them
- 12 of the Most Common Plumbing Issues with Aussie Homes












































































































