Presentation to Bay of Plenty Regional Council July 2015

Presentation to Bay of Plenty Regional Council July 2015

apple_icon_144 Lake Rotorua Primary Producers Collective

2 July 2015

We are pleased to be able to talk with you now that the alum and lake modelling science report has been released.

We have worked for a considerable time on N rules to meet the RPS target set when it was considered that controlling N was the way to get the lake to the target TLI.

StAG has only been mandated to talk about N, wider conversations about the TLI and the role of P have been resisted.

Managing P has been the success story for the lake.

The long awaited science report included alum and it has given a range of options for managing the lake. The 435t target is not now the only sustainable load target. We have been told that there is nothing in the report that would lead to choosing 435t as the sustainable load target, knowing what we know now.

Recently done economic impact studies at farm level show that the planned reductions from 2022 to meet a target of 435t by 2032 will have a devastating effect on farm businesses – their profitability and value. The last 100t reduction doing the most damage. The impact will be wide spread also affecting the beneficiaries of multiple-owned land and the 900 smaller block holders.

We believe the impact on the local economy will be considerable. Although we have a number of questions and reservations about the economic impact report, the national loss of $13 million a year ongoing is bad enough.

The question for us is about optimising the approach to managing the lake.

What mix of alum dosing, phosphorus mitigation and nitrogen mitigation would lower the economic costs to farming and the community but still achieve the TLI?

We accept there are risks and objections around alum dosing, however alum dosing could be sustainable for decades. It appears that dosing is currently showing no adverse environmental impacts.

A greater effort towards phosphorous mitigation could offset or partially substitute for alum dosing. Catchment phosphorous mitigation would have an effect within years rather than the decades before the effects of nitrogen mitigation are realised. We understand that alum is reducing the phosphorous load to the lake by 12t from 37t to 25t so the scope for pursuing this is worth looking into. Dosing is being skilfully managed to maintain total in-lake P at 20ppb, so as we get P mitigations in place alum can be reduced. An earlier desk-top exercise identified a potential 10t saving through comprehensive catchment actions.

Nitrogen mitigation achievements at farm level still need at least another 35 years to be manifest in the lake.

Nitrogen mitigation for a phosphorous limited lake is an exercise in risk management and its importance depends on the confidence around the reliability of P management such as the continuance of alum dosing or success of other P loss reductions. The science report shows that even at a nitrogen load of 435t, additional phosphorous management is required.

With the lake at target for some years now, a strategy including phosphorous management, such as including a level of alum dosing, may need to continue for Council to be compliant with the NPS requirement to maintain or improve water quality.

In Summary

Is there a chance that we can work with Council to achieve:

  • a catchment P target that contributes to lake P management, and
  • a less crippling final N target

so that:

  1. Farmers are still taking responsibility for N and P mitigation the best they can;
  2. The current TLI continues to be achieved, and;
  3. The Rotorua community is not subject to the severe economic loss inevitable under the current proposal.