Dam Failure Plans

If Commonsense fails to stop the dam and initiate safe alternative options, then the last option is to ensure that the consent conditions enforced.

Emergency Evacuation Plan 39 40 The Emergency Evacuation Plan (EEP) shall be developed in consultation with the Civil Defence Emergency Management Group, the CLG and people who are resident in the area between the Eyre and Waimakariri Rivers as approved by the Manager Monitoringand Compliance CRC, as identified in condition 37(a). The objectives of the plan shall be to: (a) (b) (c) confirm the areas identified in condition 37(a) that may be subject to inundation following a storage pond breach; outline the roles and responsibilities of the Consent Holder and other organisations involved in evacuation, with the Consent Holder retaining primary responsibility unless directed otherwise, or replaced by a competent authority; provide details on the evacuation procedures to be followed by residents and the information that may be required by other organisations in the preparation of their own evacuation plans. Performance standards for the EEP As a minimum the EEP shall include detail on: a description of the likely inundation paths (including time delays) that may occur catastrophic dam failure;

(b) warning and evacuation areas including a 'Self Evacuation Area',

(c) an 'Assisted Evacuation Area' and a 'Targeted Warning Area';

(d) the roles and responsibilities of the key organisations and agencies involved in an evacuation (see 39(b);

(e)the evacuation process (with reference to the Emergency Action Plan), including:

(i) (ii) (iii) (iv) (v) (vi)

(i) detection of an event or incident that has or may develop into a dam safety emergency;

(ii) how decisions will be made to trigger a warning and/or evacuation;

(iii) how warnings will be provided within the predicted timeframes provided by condition 40(a);

(iv) how evacuation of affected people will occur;

(v) the provision of shelter for people evacuated;

(vi) and the return of people to any area evacuated. the signage that will identify evacuation routes;

(vii) how non-permanent (or 'transient') people will be advised of the evacuation area and the possible need to evacuate; the limiting factors that might arise in relation to an evacuation and how those factors can be mitigated; and an outline of the support that will be available to provide to persons for: (i) (ii) the preparation and updating of Household Emergency Plans; and the procurement of communications devices, such as the "Scada" system, for those residents who may require them and indicate that is their preferred mode of communication of dam emergencies.

The EEP shall be certified as meeting the objectives and performance standards set out in conditions 39 and 40 by a suitably qualified and experienced person. Testing of notification systems 42 At least 3 months prior to the first filling or partial filing of the dam, the Consent Holder shall undertake a test of the emergency warning systems described in EEP: (a) the testing of the emergency warning systems shall be overseen by a suitably qualified and experienced person approved by the Manager Monitoring and Compliance, CRC; 43 44 45 46 47 The first filling or first partial filing of the dam shall not commence until such time that the certificate required by condition 42(b) has been provided to the Manager, RMA Monitoring and Compliance Canterbury Regional Council. Certification procurement for as-built construction At least two months prior to the first filling or first partial filling of the storage ponds the Consent Holder shall procure certification from a suitably qualified engineer.

Emergency Action Plan
The Consent Holder shall engage a suitably qualified and registered Chartered Professional
Engineer who:
(a) has a minimum of 10 years' experience in dam design, construction and the
preparation and peer review of documentation required for large dams; and

(b) is a Category A Recognised Engineer for the purposes of the NZSOLD Guidelines;
to prepare an Emergency Action Plan (EAP).

The objectives of the EAP shall be to ensure appropriate management of the risk associated with any uncontrolled, abnormal or excessive flow releases from the dams.
The EAP shall form part of the Dam Safety Management System addressed at conditions 27
33 and conditions 54 to 56.
The EAP shall be prepared in consultation with the CLG, provided for in RC135478 and shown
on Attachment CRC120610A which forms part of this consent; and the Civil Defence
Emergency Management Group; and shall, as far as practicable, be consistent with any Civil
Emergency Management Group Plan governing the Canterbury Region and the Waimakariri
District, pursuant to the Civil Defence Emergency Management Act 2002.
The EAP shall include as a minimum:
(a) maps of the land area located between the Eyre and Waimakariri Rivers, including land modelled as being subject to inundation in the event of abnormal or excess flow release, including emergency dewatering; the rate of inundation for land identified under 37(a);
details for:
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(i) residents and how communications will be undertaken, including contingency plans for alerting (if required) all people within the area between the Eyre River and the Waimakariri River potentially impacted by an inundation or
evacuation event;

(ii)and relevant civil defence authorities;
(iii) provision for effective consultation with all property owners including assistance with preparing individual household evacuation plans;
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(e) a description of the auto-sensory system and how it alerts the dam owner, manager and engineer in the event of a developing dam breach;
(f) provision for retaining material supplies and equipment available at short notice as specified at 5.6 of the Wrights Road storage Ponds - EEP (Preconstruction Issue) 9 June 2017 Issue 5, for use in an emergency situation;
(g) recognition of the Water Storage Commissioning Plan described in conditions 23 to 26;
(h) recognition of the Emergency Evacuation Plan (EEP) described at condition 39;
a timeline showing how the inundation area progresses with time during a dam breach; and a description as to how access to embankment crests during emergencies is to occur.
The EAP shall be consistent with the conditions of this consent (including the other required
management plans) and the Technical Specifications as they relate to the design and
operation of the Water Storage Ponds.