Managers at freshwater watchdog Environment Southland downplayed the dairy industry’s contribution to drinking water pollution, internal documents show.
From a starting position of pointing the finger at intensive dairying, an internal ES communication plan — about publicising a report on nitrate contamination — was watered down to remove references to dairy farms in its key messages.
Internal communications also show the council chose to say crops and horticulture were a potential source in the nitrate scare which closed down a water supply in Gore.
This was despite its own scientist warning colleagues the evidence "does not specifically identify arable and horticulture as ‘high-risk activities’ within the Gore context".
The revelations are in multiple revisions of the communications plan and internal ES emails obtained by the Otago Daily Times using the Local Government Official Information and Meetings Act.
Greenpeace freshwater campaigner Will Appelbe said it was "outrageous the lengths council staff have gone to massage and minimise intensive dairying’s contribution to nitrate contamination in their communications".
The emails discussed how to respond to ODT questions about dairy’s contribution to widespread and worsening nitrate in Southland groundwater and specifically the industry’s contribution to nitrate in Gore’s water supply. The town’s Coopers Wells had to be switched off last July due to nitrate spiking over the maximum allowable for health.
His report, released in February, said nitrate could travel from soil to groundwater in less than two years in many parts of Southland and the Knapdale aquifer around Coopers Wells was "vulnerable".
Winter grazing in the area included grazing of dairy cows not being milked and there was "repeated occurrence of this high-risk activity within the identified capture zone of the public supply wells".
Maps of winter grazing in the area, and an aerial photo of cows crammed in a paddock near the wells, were in the report.
The ES internal emails discussed whether the ODT could be given a response that indicated arable and horticulture, as well as dairy, could be primary culprits for Gore’s spike.
In the emails, Ms Wilson said ES might also want to "bore" the ODT reporter by saying nitrate came from a "range of sources" and there could be "lag time" between pollutants leaving these sources and reaching groundwater.
Mr Rodway emailed back, saying the report highlighted arable as a likely contributor in some Southland hot spots but "it does not specifically identify arable and horticulture as ‘high-risk activities’ within the Gore context".
Despite this, Ms Wilson sent a response to the ODT questions about the Gore situation which said "arable and horticulture" had been identified as "higher-risk activities".
Ms Wilson made her remarks about multiple sources and lag times, saying this made "any investigation ... extremely complicated". The council was doing "further work" to understand better Gore’s nitrate "situation".
The ODT asked for clarification of "winter grazing", given Ms Wilson had indicated in her response that "dairying" was a different activity from "other intensive land uses like winter grazing, arable and horticulture".
The request sparked more internal discussion.
Mr Rodway drafted a response saying winter grazing was "grazing of stock" and included "grazing of dairy cows during the non-milking season".
Ms Wilson responded to Mr Rodway and strategic regulatory adviser Bruce Halligan: "Should we say that wintering is of various animal types?"
Mr Halligan said: "Yep, good addition" — and suggested another change to Mr Rodway’s draft.
Mr Rodway had drafted that intensified agriculture was the dominant cause of nitrogen loss in Southland, with dairy the dominant intensification, but qualified that other intensified farming could cause nitrogen losses, rather than "any one sector" in isolation.
Mr Halligan suggested revised text that said intensified agriculture was "not the only driver".
Mr Rodway pushed back, saying he had altered his statement "without changing the meaning so much".
A statement was issued to the ODT, including explanation that dairy-dominated intensifying of agriculture since the 1990s "aligns" with nitrate patterns and trends in the region’s vulnerable aquifers.
Multiple versions of ES’ communication plan for the nitrate report were included in the documents released to the ODT.
The plans included "key messages" changed in a later version to remove mention of dairy and failure of council-led nitrate mitigation measures.
A version dated February 19, five days before the report was launched with a press release, said ES had monitored nitrate for 20 years and "scientific evidence is clear — intensive agricultural land uses (particularly dairy in Southland) have substantially higher nitrogen losses to water than other land uses."
It said there was increased leaching due to intensification since the 1990s and Knapdale was one of the aquifers considered at high risk of contamination.
ES mitigation efforts, including hot spot investigations and rule changes on intensification, dairy effluent and nitrate caps "have had little impact", the plan said.
A version of the plan dated February 25, the day after the report’s press release went out, had different key messages.
The messages focused on saying the science in the report was not new and had formed the basis of the Southland water and land plan, which was a "first step" in responding to the "challenges".
Intensive land use was mentioned but the reference to "particularly dairy" was removed, along with the failure of efforts to combat nitrate rises.
The messages mentioned Southland’s widespread shallow aquifers, but stressed groundwater systems "can respond slowly to land-use change".
"Improvements or reduction in nitrogen losses at the land surface may take years to decades to be reflected in groundwater quality."
Ms Wilson said communicating science was "complex", the council took it "seriously" and the council had been "clear" the likely cause of increased nitrate was "intensive land use".
She said letters were being sent, in the next few weeks, to landowners in "hot spot" areas providing nitrate information and reminding them of "the actions they can take to reduce nitrogen losses".
