We will be inspecting parts of our wastewater network in Bethlehem, Tauranga South, and Gate Pā during February - March 2026.
We may carry out up to three types of inspections. These include checking manholes in berms and roads and using smoke or dye testing on public and private property. Smoke and dye testing can also involve inspecting house pipes that run from gully traps to the Council’s wastewater network.
Why are we doing it?
We are investigating inflow and infiltration - the ways that extra water, like stormwater, groundwater, or even seawater, can enter the wastewater network.
- Inflow happens when stormwater finds its way in through damaged manhole covers, or other defects on private property.
- Infiltration occurs when groundwater seeps in through buried cracked pipes or faulty joints.
This extra water can overload the wastewater network, especially during heavy rainfall, leading to potential overflows and makes the treatment plants work harder to keep up. By reducing this extra water, we can lessen the strain on the wastewater treatment plants and create more capacity to handle future city growth, like new subdivisions.
Through our regular flow measurements and data analysis we have identified some areas with potentially high inflow and infiltration levels that require further investigation. Addressing these issues now helps ensure a more reliable and efficient wastewater system for the future.
Project timing, locations and traffic management
We will be inspecting parts of our wastewater network in Bethlehem, Tauranga South, and Gate Pā during February–March 2026. Please note these timeframes are subject to change due to weather or other unforeseen circumstances.
While works are underway, temporary traffic management will be in place where necessary to ensure the safety of our work crews and the community.
What to expect while works are underway
We’re using the smoke and dye testing method to check for inflow and infiltration. To do this, we’ll release a harmless, odourless smoke into the wastewater pipes. We may also use a safe, green, fluorescent dye. The smoke and dye will allow us to find any areas within the wastewater and stormwater pipes that need attention. During this testing process, smoke and dye may be visible in the area. The smoke is odourless and non-toxic and the dye is harmless.
Residents and businesses on affected streets will receive a letter with the timing of the work. We will only need access to the outside area of private properties to check. This work will take place during the day and there may be some noise.
FAQs
Will you be coming onto my property?
- Manhole Assessments: For the works in the Bethlehem, Gate Pa and Tauranga South areas - all inspections and tests will be conducted on both public property (e.g., manholes in roads or berms) and private property where manholes are located on private property.
- Smoke testing: In Bethlehem, Gate Pā and Tauranga South, our work crews will need to access the outside of your property (not inside) to see if the odourless and non-toxic smoke is being emitted from any stormwater drainage sources.
- Dye testing: In Bethlehem, Gate Pā and Tauranga South, where required our work crews may need to access the outside of your property (not inside) to see where the harmless green, fluorescent dye added to the stormwater network shows a connection to the wastewater system.
Will there be any noise?
There could be some minor noise and disruption, but we will try to keep it to a minimum.
What does the smoke testing involve?
Smoke testing involves releasing a dense, non-toxic, and odourless smoke into the wastewater network at a manhole. The smoke fills the wastewater main and any connected pipes (i.e. plumbing within private property) and follows the path of any breaks in pipes to the ground surface. Smoke testing contract staff monitor the locations where smoke escapes the system and is visible above ground and collect data on these locations.
Three or four people will be set up at several manholes covering 8-10 houses per set up, with each set up taking 30 minutes to 1 hour.
What does the dye testing involve?
Dye testing uses a harmless green, fluorescent dye which is added to the stormwater system to check if it connects to the wastewater network. There will be no visible signs inside your home. If the dye appears in the wastewater system, it indicates a cross-connection or leak.
Who will we notify?
We will inform all property owners, occupiers and businesses who will be affected by this work. We will also inform local emergency services such as Police and Fire and Emergency NZ about both types of works well in advance, so they know why people are working in the streets or what the source of the smoke is to avoid unnecessary call outs.