Dr Trevor Le Lievre questions the information in the Environmental Flow Optimisation Report for the Ruataniwha Dam project.
The Hawke's Bay Regional Council is under fire for announcing a million-dollar environmental fund to undertake restorative work on our worst-polluted waterways.
It's ironic that the council is drawing criticism for upholding its mandate to ensure "a clean and healthy environment".
But it's understandable in light of the previously elected council bowing to the intensive farming lobby by trying to bankroll a massive dam, thereby encouraging polluting farm ventures. Plenty of goodwill burned there.
Fortunately, the recent election delivered a pro-environment majority to council. Led by astute chairman Rex Graham, councillors Belford, Bailey, Beaven, Barker and Kirton promptly voted for a moratorium on the dam, and launched a review.
The election result delivered a clear mandate for this "cup of tea".
If the tragedy of Havelock North had a silver lining, it was the awakening in the electorates' consciousness that the state of our local waterways is in crisis, and the urgent need for management.
This local awakening symbolises a fast-growing national realisation that our farming practices have lost their equilibrium with the land that sustains them.
We are not talking here about the traditional family farm, but corporate agri-businesses farming for immediate-term returns to urban-based shareholders.
In Central Hawke's Bay the top 10 agricultural water consent holders by volume largely reflect this model.
A growing number of reports are sounding the alarm bells, and our once indisputably "clean-green" Aotearoa is now under the international spotlight.
The Organisation for Economic Co-operation and Development (OECD) in its recent report on our environmental performance highlights the link between growth in intensive dairy production and levels of nitrogen in soil, surface and ground water.
It notes further that government funding for irrigation projects lacks "systemic consideration of environmental and community costs".
Enter our newly elected regional council, and its commitment to revisit the viability of the Ruataniwha Dam. Those who have closely followed this drawn-out saga and conducted their own research already understand that this is a deeply flawed project being sold to the public on "a rising tides lifts all ships" spin.
On the financial front this is evident by both the absence of any private institutional investor, and the fact that in order to pay the council a 6 per cent dividend its investment company will need to borrow something in the order of $80 million over the project's first 20 years.
On the economic front the dam has been sold on jobs, jobs, jobs.
But the council estimates that three-quarters of projected work will be created during the first three years of the project's 12-year construction and farm conversion phase.
The certainty that this would lead to a boom-bust cycle is far greater than the likelihood of wholesale farmland conversion into orchards and vineyards, the projected source of an estimated 80 per cent increase in permanent on-farm employment.
The arguable financial and socio-economic impacts of the dam aside, it is its environmental mandate that the regional council is both legislatively and morally obligated to uphold.
On this score the dam is primarily being sold on the effect of flushing flows, as quantified in the council's Environmental Flow Optimisation Report.
This 130-page document comprises extensive modelling data and commentary, impenetrable to the layperson.
Conversely, the disclaimers appearing throughout the document are crystal clear, most notably that "the actual efficiency of the proposed flushing flows is not known with certainty". A large risk, then, which ratepayers would pay for regardless, to the tune of an additional $43m.
The available science indicates that flushing flows do not work for the simple reason that they emanate from a single point and move along a river unsupported by tributary flows, as would occur in a flood. Accordingly, they quickly lose their energy.
In the dam scenario effective flows would likely be confined to the upper reaches of the Waipawa River. From there, dislodged toxic algae would meander along to the confluence of the TukiTuki, which at that point would have collected pollutants from its six major tributaries not subject to flushing flows.
Add the towns' underperforming sewage outfalls to this mix, and this is what settles in its final repository, our ocean.
The regional council's review is due for public release on May 10.
The council needs to be wholly satisfied about only one aspect - that the uncertainties highlighted in the flushing flow report are exorcised, and the environmental benefits beyond dispute.
If this threshold is not met, it should turn to the causes of our waterways filling with pollutants, and consider alternative strategies without an $80m price tag, such as a sinking-lid policy on water consents for intensive agriculture.
Dr Trevor Le-Lievre lives in Waipukurau and holds a PhD in Political Science. He has published on governance issues and is keenly interested in local and central government politics.
Business and civic leaders, organisers, experts in their field and interest groups can contribute opinions. The views expressed here are the writer's personal opinion. and not the newspaper's. Email: editor@hbtoday.co.nz.