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TrustPower - Matahina Dam Hearing

TrustPower Ltd - Matahina Dam Final Decision and Consent Conditions

As part of the Decision and Interim Consent Conditions released on 9 December 2011, the Commissioners decided that all parties (TrustPower, Regional Council staff and submitters) were provided the opportunity to review the interim consent conditions and provide them with further written comments on the conditions. Once these comments were received the Commissioners sought additional comments from TrustPower, on two substantive matters (absolute minimum flow and mitigation methods of river bank erosion including financial contribution). Once all comments were received, the Commissioners then amended the interim consent conditions. On 23 February 2012, the Commissioners, made their final decision.

The decision itself is the same as that which was released on 9 December 2011, which is the granting of consent for a modified operating regime for the Matahina Hydro-electric Power Scheme (HEPS) under section 104A of the RMA and is summarised below.

The operational changes to the current HEPS approved by the Commissioners are to address what the applicant described as the plant's limitations and to improve the ability of the HEPS to meet the demand for energy are as follows:

              (i)       To allow for 'peaks' in generation flows from the dam operation when inflows to Lake
                        Matahina are equal to or greater than 40 cumecs;

              (ii)       To allow for the ability to 'peak' as required in response to electricity market conditions;

              (iii)       To allow the 'ramping down' rate to be at a constant 30 cumecs per hour;

              (iv)       To allow the 'ramping up' rate to be at a maximum of 97 cumecs per hour.

While the decision has remained the same, the Committee has made a number of changes throughout the consent conditions. These changes are predominately minor amendments (including minor condition rewording and changes to clarify aspects of monitoring requirements). However, there are two substantive changes to consent conditions 28 and 30. These two changes have been outlined below (changes highlighted in bold):

Condition 28

In each year (July to June) for the duration of this consent the consent holder shall undertake river bank protection works (or ensure such works are undertaken), on   behalf of and under the direction and supervision of the Bay of Plenty Regional Council (Environmental Hazards Group), in accordance with the following percentages of the Bay of Plenty Regional Council's programmed operation, maintenance and flood repair works (and associated overheads) for the Rangitaiki River for that year:

              (i)       Edgecumbe to mouth (5%)

              (ii)      Te Teko to Edgecumbe (12%)

              (iii)      Matahina to Te Teko (23%).

Condition 30

Wheninflows into Lake Matahina are less than 40 cumecs, the consent holder shall operate the Matahina Hydroelectric Power Scheme to ensure that the flow in the Rangitaiki River, immediately downstream of the Matahina Hydroelectric Power Scheme, equals, when averaged over a 24-hour period, the inflows into Lake Matahina.  At such times the consent holder shall ensure that a flow of not less than 28 cumecs is maintained in the Rangitaiki River immediately downstream of the Matahina Hydroelectric Power Scheme, at all times.

In regard to condition 28, the Commissioners considered that the percentage figures were reflective of those presented for the 40 cumecs operating regime by the applicant during the hearing process. However, it was not considered appropriate to base the contribution figure on 'actual' works as requested by the Regional Council's Environmental Hazards Group (EHG) as the Commissioners considered that the 'programmed' works provided the applicant with greater certainty to the sum of the contribution. The applicant requested that the annual contribution figure be capped but the Commissioners considered that this would go against the intention of the condition and will provide for the varying works requirements along the river margins.

In regard to condition 30, the Commissioners have maintained the fundamental aspect of the condition allowing the applicant to match outflows from the dam with inflows to Lake Matahina over a 24 hour period when inflows are less than 40 cumecs but with the addition of an absolute minimum flow during these periods of 28 cumecs. The provision of an absolute minimum is deemed necessary to better address the concerns of the submitters and goes further to avoiding adverse effects that may result during periods of low flow.

The Commissioners have provided the detailed reasoning of these changes, including the substantive changes, in the decision document. All changes made to the decision document and consent conditions are highlighted in bold for the avoidance of confusion (refer to the links below for these documents and appendices).

If you are unhappy with the decision under the provisions of section 120 of the Resource Management Act 1991, you may, within 15 working days of the release of the decision (29 February 2012), appeal to the Environment Court, Department of Justice, PO Box 7147, Wellesley Street, Auckland 1141 against the decision.  Refer to the following link to the Environment Court Form required to lodge an appeal http://www.legislation.govt.nz/regulation/public/2003/0153/latest/DLM196400.html?search=ts_regulation_forms%2c+fees_resel&p=1   

 The Decision documents can be found at the following web links:

1. 65750 Final Decision and conditions - 23 February 2012 Final (436 KB)

2. The Appendices to the decision

If you have any questions on the decision or the appeal process please contact Luke Faithfull, Consents Officer in the first instance on 0800 884 881 extn 8465 or via email at luke.faithfull@boprc.govt.nz