Sewage spills

Find out about what to do when there is a sewage spill and how to prevent sewage spills on your property.

Sewage spills are a serious health hazard to people, homes and the environment.

Please call us immediately if you see a sewage spill. 

Phone:  09 430 4200 (24 hours)

Our team will quickly identify whether the blockage is on your property or on Council’s side, free of charge.

If the blockage is on Council’s side of the network, they will clear the blockage and clean up and disinfect the ground where the overflow ran.

If the blockage turns out to be in pipes on your property, you can ask our team to do the repair and clean-up and invoice you for it. Or, you can call your own professional to take care of the repair and pay them.

Preventing sewage spills on your property

Dispose of fat correctly

Cooking fat can block pipes – put it in your rubbish and not down the sink!

When fat gets into a sewer, it forms lumps which stick to the pipe walls. Eventually the lumps become heavy enough to fall off and float down the pipe. If they are big enough, they can block the pipe completely and cause spills.

Please think carefully when disposing of fats. After cooking, let the fat cool, put it into a sealed container and then into your rubbish bin.

Pots, pans and plates should be scraped into the rubbish bin before being rinsed and washed. A sink strainer is also an effective way of stopping food scraps entering the waste system.

Commercial facilities dealing with large amounts of fat must have grease traps correctly fitted and regularly cleaned out.

Don’t use the toilet as a rubbish bin

Please don’t put rags, nappies, personal hygiene products or paper towels down the toilet as these products create blockages and can damage the pipes or get tangled up in the pumps. Dispose of these items in your rubbish bin.

Don’t plant trees over sewer pipes

Give some thought when planting trees or large bushes in your garden. Because roots extend some distance underground, try to plant trees as far away from the sewer pipe as possible. Choose species that grow slowly and do not have large invasive roots - avoid willows as they have very invasive root systems.

Your local garden centre should be able to give you good advice on which plants to use. 

Stormwater

During wet weather, rain water drains into the sewerage system and if the capacity of the system is exceeded, the wastewater can back-up and overflow from low points within it.

Low lying gully traps and water from roof downpipes are the major causes of stormwater getting into the sewerage system. Our on-going sewer inspections are identifying potential problems and helping to reduce stormwater inflows.

You can help by making sure there is no direct connection of stormwater to the sewer pipe (e.g. down pipes into the gully trap or low lying gully traps).

Don’t put hazardous waste down your toilet

Hazardous waste can stop our wastewater treatment plants from working correctly.

Waste products such as old paint, engine oil, pesticides and solvents must not be disposed of down the toilet.

Hazardous waste should be sealed in appropriate containers and taken to the nearest collection centre to be correctly disposed of.

Rubbish Stations

Sewage spill records

We record all sewage spills that occur within the district including wet weather and storm events.

The records show the start and finish date of the spill, location, estimation of the quantity, cause, the public health risk as assessed by Northland Health Board’s Medical Officer and also the action taken.

Sewage spill procedure

Read more about our response procedure for sewage spills.

Sewage Spill Procedure(PDF, 442KB)

Do not mix stormwater with wastewater

Check the spouting from your roof and make sure it is not draining into your property’s gully trap.

Spouting should be directed away from buildings to the stormwater system that drains to the sea. It should never be plumbed into gully traps that drain wastewater to the treatment plant.

Wastewater that comes from taps, toilets, washing machines, dishwashers, baths, showers and the like usually flows out of a house’s pipe, through a gully trap that has an airlock to keep sewer smells in the sewer. From there the water flows to a wastewater treatment plant for processing.

If stormwater is piped into a gully trap, or if the grated top of a gully trap is lower than any rainwater ponding on the property, then water (and sewage) can flow both ways – rainwater can run into the sewer, mix with wastewater and back flow onto the land around the gully trap.

A lot of rainwater can also overwhelm the sewer capacity, causing sewer pipes to fill up faster than they can drain, and radically increases the quantity of sewage our plants have to process.

We recommend that everyone checks where the storm water from their property is going – and makes sure it is not going into the sewer.