Council’s three waters team has recently used CCTV technology to inspect the wastewater network, identifying where stormwater is entering and reducing the system’s capacity. By tackling these issues, we avoid costly pipe upgrades and create room for future growth – a win-win for the community.
The team has been able to spot problems like low gully traps and illegal stormwater connections early, preventing bigger issues down the line. This represents significant long-term operational and capital cost savings.
The northwest part of town, from Regent Street to Edinburgh Street, has been the focus of the investigations due to the results of a stormwater inflow and groundwater infiltration study. CCTV was then used to pinpoint which pipes needed replacing. The original pipes were constructed using brittle earthenware which degrades over time through cracking and displacement. The modern uPVC or polyethylene (PE) equivalent provide a more robust network which can withstand natural disasters like earthquakes, alongside having much longer service lives.
To minimise disruption to the public, the team is using trenchless methods like pipe bursting, where a new pipe is pulled through the old one and pipe lining, where a sleeve is inserted into the pipe to reinforce it.
One example of where the surveillance work has highlighted a major problem is the sewer main below Oxford Street. There is a large void under the road caused by the loss of a section of earthenware pipe. Dislodged soil that had been around the pipe was able to flow into the network and a void was created. In extreme circumstances this can cause slumping of the road above. This could have been an exponentially higher cost to remedy had it not been discovered.
CCTV works across the wastewater and stormwater networks had a budget of $65,000 in 2024/2025 and $67,000 in the current financial year. Spend to date is $53,562.76 with further work planned.
