Nothing ruins a nice summery dip like poo in the pool. So how common is it, what’s the clean-up protocol, and is it on the rise?

Public swimming pools are so great – spaces where anyone can come for a low cost. Ah, translucent blue water, the sound of splashes, everything smelling like chlorine. Just don’t think about the sticking plasters lurking on the bottom. And please, please, don’t think about the headline “code brown cleanout missed a bit”. 

“Code brown” is pool lingo for “someone has pooed or vomited in the pool”, and it’s the part of going to a public swimming pool that everyone would rather not experience. Having to evacuate a pool for a code brown cleaning sullies the whole experience; that water dripping on the floor has had contact with the contents of someone else’s bowels. Pool staff don’t like cleaning it up. The pool loses money from people who can’t attend lessons. Journalists, writing articles about the topic in the name of public service, have to spend the greater part of their working day picturing excrement bobbing in the blue. 

There can be more serious consequences too: faeces can spread nasty bugs, and earlier this year swimming pools in the Wellington region were linked to an outbreak of cryptosporidiosis – several had to be fully drained for thorough cleaning.

Code brown events seem to be on the rise. As of the end of October, Invercargill’s Splash Palace had had to close 30 times in 2025 for faecal incidents, resulting in 58 hours of unplanned pool closure time. At that point, the pool had already had more incidents than the 28 in the entirety of 2024. After a closure last week, people were let back into the pool after 1.5 hours, then “a small amount of additional matter was found”, according to Stephen Cook, Invercargill City Council aquatic services manager. The pool had to be closed for another half hour. 

At the end of November, the Hawke’s Bay Aquatic Centre said the pool had closed 20 times due to “invasive matter” in the last six months, and incidents had been increasing. The pool had issued an awareness post on Facebook asking pool-goers to “do their bit to prevent further disruptions”.

It isn’t the first time pools have hit headlines for unwanted body ejections. In Auckland in 2022, pools had to close more than 400 times for “code brown” incidents. In the last full financial year (June 2024-25) there were 595 hours of closures. Since July 2025, there have been 318 hours of closures due to “bio hazard incidents). This might seem a lot, but given that the council operates or oversees 27 pools through the region, less than 1% of swimming lessons had to be cancelled or rescheduled as a result. “We always aim to provide welcoming, family-friendly environments with high hygiene standards, particularly in our pools. However, accidents do happen,” said Arvid Ditchburn, general manager of pools and leisure at Auckland Council.

In 2019, Christchurch’s QEII pool had to close a pool 328 times due to faecal matter or vomit. Most of those closures were in the toddlers’ pool and teaching pool. Auckland Council has run educational campaigns trying to prevent these incidents from happening. Because not all incidents are tracked, it’s impossible to say for sure whether incidents are on the rise. 

There’s a clear protocol when the waters have been muddied by code browns. At Splash Palace, “this includes closing the affected pool, cleaning up the material, super-chlorinating the water and keeping the pool closed for between 30 minutes and 12 hours, depending on the type of material involved”, said Cook. The process is externally verified by PoolSafe, an independent quality management system for public pools. 

It was difficult to place an exact cost on the effect of the closures, Cook said. “However, these incidents use additional materials, take up staff time and affect our admissions and regular schedule of swimming classes.”

Better yet, of course, is to prevent these incidents in the first place. With children the most likely culprits, Christchurch City Council has a page of advice for parents. Before entering a pool, they recommend “allowing food to settle” and taking kids to the toilet. Children need to know that it’s OK to leave a swimming lesson to go to the toilet; no one should be in the pool if they’ve had diarrhoea in the last two weeks and swimming nappies should be checked regularly.

It’s important for people of all ages and abilities to be able to access pools, which provide safe places to exercise and play at all times of year. Most public pools in New Zealand are run by councils as a community facility, from shallow toddler pools to swirling lazy rivers and lanes for doing laps. Making pools accessible to all means that some incidents of bodily fluids (and worse, bodily solids) are inevitable, despite precautions. 

While the cause of faecal incidents in pools tends to be pretty obvious, dealing with poo in the water isn’t just an issue indoors. Sewage overflows plague outdoor swimming spots in New Zealand’s cities. Unlike code browns in swimming pools, fixing contamination in these areas requires major infrastructure upgrades and investment to prevent. 

Auckland’s Central Interceptor sewage pipe will be fully operational from 2026, replacing ageing pipes where stormwater and wastewater are combined – meaning big rain storms often lead to sewage spills on Auckland’s central beaches. The pipe is intended to last for a century, and cleaner swimming will be a major benefit. Elsewhere in the country, like in Wellington, water is generally safe but swimmers are recommended to not dive in for 48 hours following heavy rain. 

It’s good, then, that chlorine is so efficient at killing bacteria – and that pools are able to deal with faecal incidents much more quickly and efficiently than politicians and bureaucrats have been able to with the same trouble in oceans and rivers. This summer, if you make it to an indoor or outdoor pool to enjoy the good parts of publicly subsidised bodies of water, spare a thought for the pool staff who have to deal with code browns.