Bruce Bisset: Is updated software fit for purpose?

Bruce Bisset.

COMMENT

If you had a software tool that was currently undergoing a thorough government-initiated peer review, would you use it as the basis for estimating nutrient run-off from your farm?

Moreover, if you were a council, would you use it as part of a Plan Change, without any public consultation, as the peer review was happening?

That's what the Hawke's Bay Regional Council has just tried to do with its "tweaking" of the way nitrogen leaching is modelled on farms in the Tukituki catchment.

But because freshwater planning now has to be considered under new planning processes, Environment Minister David Parker has rejected its application.

Overseer, or OverseerFM as its new iteration is known, is the software under scrutiny.

HBRC is one of six regional councils which currently accepts it as a valid management tool to underpin their regulatory nutrient regime, which farmers must comply with.

Around 11,000 farms nationwide use the software for on-farm nutrient management.

Originally developed by Ravensdown and Ballance – two companies that control 98 per cent of New Zealand's fertiliser market – it's touted as a way to "optimise production and minimise losses of nutrients to the environment".

Note that first target.

Overseer is, now, equally jointly owned by the Ministry for Primary Industry, Crown-owned agency AgResearch, and the two fertiliser companies.

You might think this provides some surety the updated software is fit for purpose as a regulatory tool – and perhaps it is.

But the source-code – the bits protected by intellectual copyright, as developed by the fertiliser industry – remains secret, despite considerable expert criticism suggesting the mathematical algorithms likely favour the application of fertiliser rather than mitigation of its impacts.

Following Parliamentary Commissioner for the Environment Simon Upton's call for public scrutiny in his 2018 investigation, a holistic review is, at last, looking at that source code along with every other aspect of the program and its implementation.

The review panel's report is due in March next year. Only then will anyone know whether, in Upton's words, it can be "confidently used in a regulatory context".

Meanwhile HBRC, along with Horizons and four other councils, already uses it as the "best available" tool for its purposes – even though they admit they don't fully trust it.

I can sympathise with their rock and a hard place position, but that's not good enough when you try to effect a Plan Change to the "gateway" modelling that increases the recorded amount of leaching allowed by between 41-69 per cent (depending on the land in question).

HBRC contends the "increase" is illusory because the amount of nitrogen entering waterways will stay the same; it's the tool that's changed through more accurately measuring leachate that is removed by natural processes before reaching freshwater.

So, the rationale goes, if the relevant table isn't amended more farmers will have to apply for costly non-complying consents when they shouldn't have to, given there's no additional impact on in-stream nitrogen.

I get that this is a "technical" fix to maintain the status quo in good faith. What I don't agree with is the assumption the "extra" Nitrogen isn't going somewhere else – like into the aquifer, creating a "legacy" problem.

And surely, at a time when we should be reducing chemical inputs, this is exactly the sort of issue the public deserves the right to have a say on.

- *Bruce Bisset is a freelance writer and poet. Views expressed are the writer's opinion and not the newspaper's.