Lake Rotorua is an inspiring story of farmers, the community and local council doing their bit to get the lake's water quality going in the right direction. As a result it has hit agreed water quality targets decades before it was thought possible.
This result, and how it was achieved, turns many perceptions on improving degraded water bodies on their head.
The lake was in a bad way after decades of contaminants from humans, animals and industry, as well as geothermal activity.
In November 2010 the Bay of Plenty Regional Council publicly notified its second Regional Policy Statement (RPS), which contained a proposal to reduce nitrogen (N) deposits in Lake Rotorua by 45 per cent within the 10 years between 2009 and 2019.
Federated Farmers submitted against this new policy, then appealed to the Environment Court on the grounds that its impact on current landowners and the local economy would result in great hardship for both. Importantly, the Federation said the proposed plan would not actually achieve the agreed water quality target.
This target was a Trophic Level Index (TLI) of 4.2. The TLI is a composite measure, combining N levels, phosphorus (P) levels, water clarity and algal biomass levels. Eight years ago the lake had a TLI of 4.8 - which equates to poor water quality.
Last year the council's and DairyNZ's scientists, who have been analysing the monitoring results, agreed that for each of the last eight years the water quality has become significantly better. Crucially, last year Lake Rotorua reached a TLI of 4.1, squarely in 'average' water quality - an incredible result in just eight years.
These results were achieved by a combination of actions from many parties. The regional council used nutrient-locking technology to make some P unavailable, Rotorua District Council changed the way it discharges sewage, central Government helped the community upgrade their old leaky septic tanks and farmers have changed their management practice, installing expensive capital items to significantly reduce their N loading. All of this added up to water quality way beyond what could have been achieved without a combined effort.
Once what was happening in the lake was agreed, the parties could sit down and find a way forward. The Oturoa Agreement lays a pathway for a staged approach over 20 years, using managed nitrate reduction from land-users, in conjunction with regular scientific checks that the lake at least maintains water quality.
This is a Memorandum of Understanding between Federated Farmers, Bay of Plenty Regional Council and the Lake Rotorua Primary Producers Collective Incorporated, with the support of the Lakes Water Quality Society.
Checks will be done with council and DairyNZ scientists, giving confidence that objective science is being applied.
Why is this all so important? It categorically shows what is possible with the right collaborative community approach and that the nitrate myopia of some other councils will not actually produce efficient, effective and enduring outcomes for water quality.