Southland stream life wiped out by single contaminant dump

Two months ago the humble Low Burn Stream was teeming with life: freshwater crayfish, galaxiids, eels, trout and bugs galore.

Even the farmers whose land it runs through were unaware of the abundance of creatures, until the whole lot were wiped out by a single dump of contaminant from private land.

In the aftermath, 3000 rotting eels (tuna) were removed along the 10km stretch of water as well as a scattering of other species. The latter, too small to get caught up in vegetation, were likely carried downstream in the contaminated water, directly into the already-compromised Mataura River.

Regional council authority, Environment Southland, says the discovery and collection of dead eels was a “highly distressing situation” for staff and helpers. The matter may now be headed for prosecution the district court.

The incident has riled many farmers and residents, with some wanting penalties that pack more punch than a fine.

It has also highlighted the dire state of the water in some of Southland’s lower reaches, with statistics on faecal bacteria contamination (E. coli) nitrogen, phosphorus and sediment levels likely to put some people off their morning coffee.

“I was devastated by how many eels were lost,” says farmer Steven Clarke. “We’ve only got 300 metres of stream going through our place and I counted 70 dead eels in the 300 metres. I’ve been here for 11 years and I’ve riparian planted and fenced off the whole lot down there and I never knew it held that amount of eels. The stream was incredibly healthy beforehand because of all the good work farmers have been doing.”

Clarke is vice president of the Three Rivers Catchment group, one of 37 such groups across the province focusing on environmental protection work and education. Taking in sections of the Mataura, Mokoreta and Mimihau River catchments, the group has 50 members.

He says a few farmers still “had their heads in the sand”, but most were working hard to protect waterways. Running fewer cows, using less nitrogen and growing plants that reduced leaching into waterways were now well-established practices.

The Low Burn incident reflected badly on all farmers and many were feeling that discomfort.

“Something’s got in that’s taken all the oxygen out of the water and tipped all these eels upside down. Everyone was pretty disheartened. It brings the whole community down; we all get kind of tainted with that brush.”

Because an investigation is still underway, no information is being released by Environment Southland as to what the contaminant was, how it entered the water or how long it might take to find those things out.

The lack of information is frustrating those affected.

“I don’t know what’s happened upstream,” Clarke says, “but someone needs to put their hand up and tell us what happened and something can be learnt from it. We just need to make sure it doesn’t happen again.”

Streams are not sewers

Among those assisting with collecting dead eels were members of the Hokonui Runanga, including young people who had been studying freshwater species as part of the group’s conservation work.

Efforts to re-establish populations of a mysterious jawless fish which was once a prized food source for Māori were also likely to have taken a hit in the February pollution event. The lamprey, or kanakana, which pre-dates the dinosaurs, is an elusive eel-like creature, whose success in life is dependent on clean water and the absence of physical barriers across streams and rivers.  

As well as species rehabilitation, the Runanga’s environmental department undertakes policy and planning work, pest control, water quality monitoring and operates a native plant nursery.

Environmental scientist and Runanga spokesperson Riki Parata says the discharge of contaminant, even by accident, is plain negligence. Local iwi and farmers spoken to had all been “quite horrified” by it. 

Economic pressures are no excuse, Parata says.

“Everything was wiped out of that stream. Whatever it was, was a significant pollutant. It shouldn’t happen. It’s inexcusable but I feel it’s from a very minor representation of the population.

He believes the problem is partly a “generational thing” and a systemic change of thinking was required.

“We shouldn’t be treating our waterways like this. Gone are the days when you used to just dump everything into the rivers; those are old, old practices. For real change to happen everybody as a whole needs to start thinking about how we treat our rivers and streams a bit differently.”

Southland’s wider water quality is a concern, he says, with already-high nitrogen loads getting higher and the Mataura River recently having recorded the third-highest levels of E. coli in the country.

At Low Burn, Parata believes it could be a few years before the macro-invertebrates (bugs), and then larger species, re-establish, if they return at all.

Penalties for such damage were generally in the form of warnings and fines but Parata says that won’t help the stream.

“We want to see that stream reinstated; that’s where the money should be going and it should be going toward research on that and education around preventative actions for it not to be happening again.”

He says the fear was that such incidents would become treated as the norm if they were not highlighted and dealt with in a way that set an example to others.

“As tangata whenua who really care about the environment … people that do that shouldn’t be allowed to operate farms.”

Something’s in the water

Southland’s rivers and streams have some of the highest levels of sediment, nitrogen and phosphorus in the country. Water issues have now become Environment Southland’s highest priority as it works hard to turn around worrying trends.

Faecal bacteria levels are also high from a national perspective, according to a report by the authority.

Further downstream, Southland’s estuaries, lagoons and coastal lakes, where much of the river and stream water ends up, are showing “signs of stress”.

“Ongoing measurements have found that the estuaries and lagoons in the region are rapidly deteriorating due to excess sediment and nutrients. This includes three of the region’s main river catchments – Jacobs River Estuary, New River Estuary and Waiau Lagoon.”

Nitrogen levels would need to be almost halved for Southland’s water to achieve even the bottom lines of national standards. Meeting local planning targets would require a reduction of between 66 and 70 percent for both nitrogen and phosphorus.

The council is seeking a whopping 82 percent reduction in E. coli levels to achieve standards laid out in its proposed Southland Water and Land Plan.

In the Mataura catchment, of the 25 sites Environment Southland monitors, only four pass national standards for nitrogen levels and all three sites monitored for safe swimming fail the test because of high E. coli levels.

In terms of what’s going into the water, the catchment currently has 22 consented discharges of wastewater to water. These include 11 municipal discharges and four from meat works and the milk and dairy industries.

The use of water drawn from various sources through consented water takes is dominated by irrigation (39 percent) and industry (33 percent). Town supplies represent 15 percent of water taken and livestock 13 percent.

Environment Southland chief scientist Karen Wilson says the public needs to be aware of risks associated with E. coli when in contact with the Mataura River as well as other rivers and streams in the region. The bacteria signified likely faecal contamination, meaning there was a risk that faecal pathogens, or microorganisms that cause illness such as campylobacter or giardia, might also be present. 

She says the council’s essential monitoring work represents a “compromise” between available resources and the multiple data needs that the council’s programmes supported.

Speaking about the Low Burn incident, Environment Southland resource management manager Donna Ferguson says details of findings would only be made public once the investigation is completed.

“However, if court proceedings are initiated, the publishing of any evidence will be at the discretion of the courts.”

The council declined to comment on the effectiveness of monetary penalties or possible alternatives, confirming only that any proceeds Environment Southland might collect would be used to assist in recovering the costs of the investigation.

“Should court proceedings be initiated by a prosecution, the courts will have the discretion to enforce a range of penalties.”

Meanwhile, Thriving Southland, a support organisation for catchment groups doing environmental and other work, says 90 percent of the province’s productive land now has a group working on it.

Project lead Richard Kyte says around 1500 farmers and residents are members in Southland.

Thriving Southland declined to comment on the Low Burn incident saying it had no information on how or why it had happened.

Asked what could help improve the region’s water issues, Kyte said there was already a “significant amount of good work” on water quality being done by catchment groups and Southland farmers.

“We encourage all people to join their local catchment group, get involved and be part of the solution.”