A proposal put forward by BoPRC in late 2019 seeks to undertake a 3-year trial consisting of a modified operational management regime for Lake Rotoiti including a one-off drawdown to a targeted low level and held for one week (in lieu of the winter flush) to allow iwi, in particular, and other stakeholder representatives to observe the various impacts first-hand and decide whether any operational changes could be warranted. The Rotorua Te Arawa Operational Liaison Group, on which LRCA is represented, met in November 2019 and unanimously agreed to support this proposal in principle. A more detailed report is contained in our newsletter of December 2019. The matter was subjected to considerable debate at our January 2020 AGM. An Application to vary the existing Consent based on the above proposals has been lodged by BoPRC and currently awaits decision. If granted, BoPRC intend to organise a boat trip around the lake and include representatives of the various stakeholder groups to observe and record what impacts this low level has on the lake environs and its residents.
Lake Level Trial Resources
In July 1972 the Bay of Plenty Catchment Commission (BOPCC - Regional Water Board) promulgated revised Water Right applications for proposed proposed new diversion and discharge works to increase flows and alleviate flooding and high lake levels in and around Lakes Rotorua and Rotoiti as part of the overall flood control scheme for the Kaituna Catchment. Details of the proposed works were to:-
- Construct an additional inlet to the Ohau Channel using a control weir to regulate.
- Widen and deepen the Channel from the inlet to a proposed diversion cut with accompanying control structure downstream from the SH33 bridge which ‘would be sited and operated in such a way that the existing length of the Channel remains unaltered during times of normal lake levels and flows, thus retaining the present delta at the outlet from silting up’.
- Increase and regulate the flow from Lake Rotoiti at the entrance to the Okere River by lowering the level of the rock bar at the head of the rapids and provision of a control structure with moveable gates to retain the level of the lake within set limits.
The diversion cut never eventuated but the control gates at Okere were eventually installed in 1982 and the control weir at the head of the Ohau Channel in 1989.
After concerns were raised by this Association in the mid 1990s during prolonged periods of low lake levels, the original consents were officially reviewed by the controlling body, Bay of Plenty Regional Council (BoPRC) resulting in amended conditions being promulgated in late 1996 to provide for a narrower operating range. This regime prevailed until 2009 when, with the consents due to expire, Ngāti Pikiao iwi representatives began a campaign for a return to natural lake fluctuations and the removal of the Okere Control gates on the premise that its existence and operational management had caused significant detrimental impacts on the lake ecology and on local communities in terms of their economic, social, environmental and cultural well-being.
Following initial consultation hui between BoPRC and local iwi, Council promulgated a proposal to renew the consents, details of which were summarised in the LRCA Newsletter of December 2009. The intention to operate Rotoiti lake levels within a much wider range raised immediate concerns relating to the potential impact on the improvement in lake water quality since the construction of the $10 million Ohau Diversion Wall designed to direct nutrient-laden Lake Rotorua outflow towards the Kaituna river and away from the body of Lake Rotoiti. There were also implications of increased potential for property inundation and likely impact on the ability to pursue boating and recreational activities on the lake.
A public meeting convened by LRCA on 3 January 2010 attracted a huge attendance with more than 550 residents and interested parties gathered to hear and express concerns over the new proposals. The meeting mandated LRCA ‘to seek retention of the Okere gates and existing consent conditions, and represent the community in conducting negotiations and proceedings as it saw fit’. Subsequently, a number of consultation meetings and open days were held resulting in a revised Consent Application being notified by BoPRC in July 2010. Following multiple submissions, with LRCA having been further mandated to support the amended proposals, the case was heard in front of three Environment Commissioners culminating in a favourable decision being notified in late January 2011.
However, an appeal lodged with the Environment Court by the Ngāti Pikiao Environmental Society prolonged the implementation of the revised Consents and Operating Conditions. This resulted in various mediation meetings being held after which Consent Condition Amendments were finally agreed to by all parties and signed off on 26 March 2012. A comprehensive and detailed outline of all proceedings can be found in the Association newsletters of 2010 through to August 2012, (which are archived on this website). Since that time, Ngāti Pikiao has produced a Cultural Impact Assessment of Rotoiti lake level management which further identified a number of the afore-mentioned issues of importance to local iwi. These issues have been subject to ongoing discussion and debate primarily between BoPRC, Iwi and LRCA.