EMERGENCY ACTION PLAN - SPLITYARD CREEK DAM ISSUE: 12 - dnrm.qld.gov.au
←
→
Page content transcription
If your browser does not render page correctly, please read the page content below
EMERGENCY ACTION PLAN – SPLITYARD CREEK DAM
ISSUE: 12 Date: February 2020
Prepared by CS Energy/GHD Limited 1
Controlled Copy No:
Gated: No Manned: Yes 2
Type: Earth and rock-fill embankment
Project: Splityard Creek Dam EAP File no.: F/19/1991
Rural no.: 683 Wivenhoe Somerset Road (Power Station)
Location: Lat. -27.371944o (27°22'19"S)
Lon. 152.640833o (152°38'27"E)
Approved by the delegate of the Chief Executive,
Department of Natural Resources, Mines and
Energy until 1 September 2021
DISCLAIMER: This report has been produced by CS Energy to provide information for client use only. The information contained in this report is limited
by the scope and the purpose of the study and should not be regarded as completely exhaustive. This report contains confidential information or
information which may be commercially sensitive. If you wish to disclose this report to a third party, rely on any part of this report, use or quote
information from this report in studies external to the Corporation, permission must first be obtained from the Chief Executive, CS Energy.
1 SunWater template
2 Monday to Friday
Splityard Creek Dam - 2019/20 - i12
Emergency activation quick reference – Dam hazards
The Emergency Action Plan (EAP) for Splityard Creek Dam covers three emergency conditions evaluated within CS Energy’s Dam Safety Management Program.
Use Table 1 to select the relevant section of the EAP that deals with the emergency condition.
Note: The Incident Coordinator (IC) is responsible for activating the EAP unless otherwise directed by the Dam Safety Technical Decision Maker (DSTDM).
Should the IC be unavailable, the Dam Duty Officer (DDO) is responsible.
Table 1: Emergency activation quick reference – Dam hazards
Dam hazards and Activation levels for dam hazards
section numbers Alert Lean Forward Stand Up Stand Down
Piping: embankment, • Increasing leakage through dam • Increasing leakage through an 1. Piping condition has been established • Risk assessment has determined that
foundation or embankment, foundations or abutments embankment, the foundations or 2. Failure in progress or likely due to piping, and sufficient piping risk has reduced
abutments abutments with cloudy water water in storage to create a dam failure hazard
See section 5 • EAP activated
Earthquake • Earthquake reported or felt in the area • Earthquake reported or felt in the area 1. Earthquake reported or felt in the area, and a possible • No change detected or no damage found
See section 6 • Intensity less than 5 MM (using Modified failure path has been identified during the inspections, or
• Intensity greater than or equal to 5 MM, or
Mercalli Scale in Appendix H Figure 13 2. Failure in progress or likely due to earthquake, and • Risk assessment has determined that
• Intensity less than 5 MM and change
sufficient water in storage to create a dam failure failure risk has reduced to an acceptable
detected during surveillance inspection
hazard level
• EAP activated
• Repairs completed as necessary
Terrorist threat / activity • Alert/brief received from QPS Security and Counter-Terrorism Command relevant to dam 1. Possible terrorist activity or suspicious behaviour noticed • No damage found during the inspections, or
or high energy impact safety at the dam, threat received relevant to dam safety, and
EAP activated • Risk assessment has determined that
See section 7 failure risk has reduced
2. Large explosion heard/observed at the dam (e.g. bomb
• Repairs completed as necessary
explosion, aircraft hit), and damage observed on the dam
3. Failure in progress or likely due to impact or explosion,
and sufficient water in storage to create a dam failure
hazard
Splityard Creek Dam - EAP v12 Page ii
Splityard Creek Dam - 2019/20 - i12
Table of Contents
Emergency activation quick reference – Dam hazards.................................................................... ii
Document control ......................................................................................................................viii
Document revision history ........................................................................................................... ix
Controlled document distribution list............................................................................................ x
1. References, abbreviations and definitions ........................................................................... 1
1.1 References/associated documents ...................................................................................1
1.2 Abbreviations and acronyms ............................................................................................3
1.3 Business terms and definitions .........................................................................................4
2. Introduction ....................................................................................................................... 7
2.1 Context ..............................................................................................................................7
2.2 Purpose .............................................................................................................................8
2.3 Scope .................................................................................................................................8
2.4 CS Energy/CleanCo provides training ...............................................................................8
2.5 Dam emergency organisation within CS Energy/CleanCo ................................................9
2.6 Community information ...................................................................................................9
2.7 Lessons Learnt.................................................................................................................10
2.8 Downstream notification lists .........................................................................................10
2.9 Comprehensive Risk Assessments ..................................................................................10
3. Roles and responsibilities .................................................................................................. 11
4. Dam details ...................................................................................................................... 15
4.1 General dam information ...............................................................................................15
4.2 Population at risk ............................................................................................................16
4.3 Spillway adequacy and reservoir water releases ............................................................16
4.4 General arrangement......................................................................................................16
4.5 Emergency inspections and monitoring .........................................................................17
5. Dam hazard – Piping: embankment, foundation or abutments ........................................... 18
5.1 Overview .........................................................................................................................18
5.2 Emergency Actions..........................................................................................................18
6. Dam hazard – Earthquake ................................................................................................. 26
6.1 Overview .........................................................................................................................26
6.2 Emergency Actions..........................................................................................................26
7. Dam hazard – Terrorist threat/activity or high energy impact............................................. 34
7.1 Overview .........................................................................................................................34
7.2 Emergency Actions..........................................................................................................34
Splityard Creek Dam - EAP v12 Page iv
Splityard Creek Dam - 2019/20 - i12
Notifications and communication lists ................................................................. 41
Flood impact downstream and inundation maps ................................................. 55
Routine and emergency access routes ................................................................. 58
Machinery and equipment .................................................................................. 60
Technical information ......................................................................................... 61
Summary of legal requirements .......................................................................... 69
Notices from local government and district groups including responses ............... 70
Emergency action plan – toolkit .......................................................................... 73
Splityard Creek Dam - EAP v12 Page v
Splityard Creek Dam - 2019/20 - i12 List of Tables Table 1: Emergency activation quick reference – Dam hazards Table 2: Splityard Creek Dam specifications Table 3: Piping: Embankment, foundation or abutments – DDO emergency action Table 4: Piping: Embankment, foundation or abutments – IC emergency action Table 5: Piping: Embankment, foundation or abutments – IC external communication plan Table 6: Piping: Embankment, foundation or abutments –DSTDM emergency action Table 7: Earthquake – DDO emergency action Table 8: Earthquake – IC emergency action Table 9: Earthquake – IC external communication plan Table 10: Earthquake –DSTDM emergency action Table 11: Terrorist threat/activity or high energy impact – DDO emergency action Table 12: Terrorist threat/activity or high energy impact – IC emergency action Table 13: Terrorist threat/activity or high energy impact – IC external communication plan Table 14: Terrorist threat/activity or high energy impact –DSTDM emergency action Table 15: List of machinery and equipment available during an emergency Splityard Creek Dam - EAP v12 Page vi
Splityard Creek Dam - 2019/20 - i12 List of Figures Figure 1: CS Energy / CleanCo emergency response organisation Figure 2 Plan of the Splityard Creek Dam Figure 3: Dam hazard – Piping: embankment, foundation or abutments flowchart Figure 4: Dam hazard – Earthquake flowchart Figure 5: Terrorist threat/activity or high energy impact Figure 6: Emergency alert polygon Figure 7: Sunny Day Failure (SDF) flood extent and PAR property locations Figure 8 Emergency Alert Request Form Figure 9: Modelled peak flood velocities Figure 10: Modelled peak flood depths Figure 11 Map of emergency access routes Figure 12: Local Government Notice Figure 13: Modified Mercalli Scale for earthquake magnitude assessment Splityard Creek Dam - EAP v12 Page vii
Splityard Creek Dam - 2019/20 - i12
Document control
Authorisation of document
This document has been reviewed and accepted by the following:
Name Position/role Signature/date
GHD Technical Director – Prepared for See B/D/19/21075
Submission
GHD Senior Technical Director – Reviewer See B/D/19/21075
CS Energy Site Manager Wivenhoe – See B/D/19/21075
Prepared for submission
CS Energy Lead Hydro Engineer – Reviewer See B/D/19/21075
CS Energy Manager Balance of Plant – See B/D/19/21075
Approver
CS Energy Dam Safety – Approved for See B/D/19/21075
submission
CleanCo Dam Safety – Approved for
submission
CleanCo Executive General Manager
Transition - Approver
20/01/2020
Splityard Creek Dam - EAP v12 Page viii
Splityard Creek Dam - 2019/20 - i12
Document revision history
Version Date Prepared by Reason for change
1 19/01/2001 SunWater Initial Issue
2 20/02/2002 Revision of Pt 1, Pt 2, Pt 4 and Pt 6
3 26/03/2003 Notification list revised and formatted
4 08/04/2008 Document completely revised and various changes made
5 10/11/2010 Document revised and various changes made
6 20/12/2011 Document substantially revised to incorporate Qld Floods
CS Energy Commission of Inquiry recommendations and to create Part 1
that contains Actions and Technical Data, and Part 2 that
contains contact details only.
7 30/09/2013 SunWater Revised in accordance with amendments to the Water Supply
(Safety and Reliability) Act 2008 and provisional guidelines for
Emergency Action Planning for Referable Dams, June 2013 as
issued by DEWS. [Incorporating Amendment No 1]
8 29/09/2017 SunWater Revised in accordance with amendments to the Water Supply
Act
9 26/07/2019 GHD Document updated to incorporate dam hazard tables,
activation triggers, communications plans and better align
with the SunWater standard EAP.
9.1 28/11/19 CS Energy Minor updates to include change of ownership details.
10 21/01/20 CleanCo At the request of the Dam Safety Regulators office, a new
version has been issued to more clearly identify the latest
update to the EAP. Versions 9.1 and 10 comprise non-
substantive changes, which primarily include the addition of
CleanCo as the new Dam Owner, new contact details for
CleanCo personnel roles within the EAP, a new figure for the
Emergency Alert Polygon and corrections for minor formatting
errors.
11 7/02/20 CleanCo Update the references and contact details for the CleanCo
delegated EGMAM to General Manager Asset
Operations. Correct email addresses for the CEO and
12 27/02/20 CleanCo Somerset CEO and Local Disaster Coordinator contact details
updated.
Splityard Creek Dam - EAP v12 Page ix
Splityard Creek Dam - 2019/20 - i12
Controlled document distribution list
Copy
Position Location
no.
1 Site Manager Wivenhoe CS Energy, Wivenhoe Power Station
2 Civil Engineer - Asset Management CleanCo, Brisbane Office
3 Pool Trading Desk CleanCo, Brisbane Office
4 Director Dam Safety Department of Natural Resources,
Mining and Energy, Brisbane
5 Local Disaster Coordinator – Local Disaster Management Somerset Regional Council, Esk
Group (LDMG)
6 Officer in Charge Lowood Police Station
7 District Disaster Coordinator – Ipswich District Disaster Ipswich District Police Headquarters
Management Group (DDMG)
8 Director Disaster Management Services State Disaster Coordination Centre –
Queensland Fire and Emergency
Services, Brisbane
9 CleanCo General Manager Asset Operations CleanCo, Brisbane Office
Notes: Communication information for each ‘Controlled Copy Holder’ is attached in Appendix A
Splityard Creek Dam - EAP v12 Page x
Splityard Creek Dam - 2019/20 - i12
1. References, abbreviations and definitions
1.1 References/associated documents
Ref. Document title Reference/location
https://www.legislation.qld.gov.au/view/pdf/
A Water Supply (Safety and Reliability) Act 2008
2017-07-03/act-2008-034
Queensland Disaster Management Act 2003 https://www.legislation.qld.gov.au/view/pdf/i
B
nforce/current/act-2003-091
C Queensland Disaster Management Guidelines http://www.disaster.qld.gov.au
Guidelines on Selection of Acceptable Flood ANCOLD
D
Capacity for Dams (ANCOLD, 2000)
Queensland Dam Safety Management Guidelines https://www.dnrme.qld.gov.au/__data/assets
E
(DNRME 2002) /pdf_file/0007/78838/qnrm02013.pdf
Australian Rainfall and Runoff (ARR) 2016 http://book.arr.org.au.s3-website-ap-
F
southeast-2.amazonaws.com/
Emergency action plan for referable dam guideline https://www.dnrme.qld.gov.au/__data/assets
G
(DNRME 2017) /pdf_file/0018/84015/eap-guideline.pdf
Queensland State Disaster Management Plan 2016 Queensland-State-Disaster-Management-Plan
H (Queensland’s Disaster Management
Arrangements)
Queensland Government arrangements for https://www.disaster.qld.gov.au/dmg/st/Doc
I coordinating public information in a crisis uments/H1159-Public-Information-Crisis-
Communication-Document.pdf
Professional Engineers Act 2002 (RPEQ) https://www.legislation.qld.gov.au/view/pdf/i
J
nforce/2013-09-23/act-2002-054
Guidelines for the Development of Communication https://knowledge.aidr.org.au/media/1970/m
Education, Awareness and Engagement Programs anual-45-guidelines-for-the-development-of-
K
(Australian Institute for Disaster Resilience 2002) communication-education-awareness-and-
engagement-programs.pdf
Queensland Emergency Alert Manual – M.1.174 https://www.disaster.qld.gov.au/dmg/st/Doc
L uments/M1174-Queensland-Emergency-
Alert-Manual.pdf
Business Queensland—Map and list of emergency https://www.business.qld.gov.au/industries/
action plans for referable dams mining-energy-water/water/industry-
M
infrastructure/dams/emergency-action-
plans/map
Procedure – CS-IM-02 - Crisis Management (CS B/D/11/43851
N
Energy)
Procedure – CS-IM-03 - Emergency Response Plan B/D/12/14048
O
(CS Energy)
P Splityard Creek Dam Safety Condition Schedule B/D/15/12897
Guidelines on Consequence Categories for Dams ANCOLD ISBN: 978-0-9808192-5-0
Q
(ANCOLD, 2012)
Splityard Creek Dam - EAP v12 Page 1Splityard Creek Dam - 2019/20 - i12
Guideline for Failure Impact Assessment of Water https://www.dews.qld.gov.au/__data/assets/
R Dams (DNRME 2018) pdf_file/0005/78836/guidelines-failure-
impact-assessment.pdf
CS Energy Splityard Creek Dam Failure Impact B/D/19/1591
S
Assessment August 2017
CS Energy Splityard Creek Dam Comprehensive Risk Scheduled to be carried out in 2020
T
Assessment
Guidelines on Dam Safety Management (ANCOLD, ANCOLD ISBN: 0-731027620
U
2003)
CS Energy Inundation/Flooding of Public Roads To be developed
V
Policy
Queensland Rainfall and River Conditions (BOM- http://www.bom.gov.au/qld/flood/index.sht
W
Flood Warning) ml?ref=hdr
X CS Energy Emergency Alert Protocol Appendix A
CS Energy – SAP Incident Reporting & Management SAP
Y
System
Procedure - WIV-MAN-13 - Incident Response W/D/12/1267
Z
(Wivenhoe Power Station)
Procedure - WIV-OPS-15 - High Rainfall High Dam W/D/11/111
AA
Water Levels (Wivenhoe Power Station)
Procedure - CS-TRAD-01 - Wivenhoe Power Station B/D/11/46292
BB Water Movement Notification to SEQWater (CS
Energy)
Procedure - WIV-COMMS-01 - Communications B/D/12/79098
CC Protocol with Seqwater - Water Movements
(Splityard Creek Dam / Wivenhoe Dam)
DD Standard Operating Procedures (Splityard Creek Dam) F/11/8636 (TRIM RM Folder)
Water Act 2000 https://www.legislation.qld.gov.au/view/pdf/
EE
2017-07-03/act-2000-034
Manual - Operation and Maintenance (Splityard W/D/13/644
FF
Creek Dam)
Somerset Regional Council Local Disaster http://www.floodcommission.qld.gov.au/__d
Management Plan v2 August 2009 ata/assets/pdf_file/0018/7713/QFCI_Exhibit_
GG 324_-
_Somerset_Regional_Council_Local_Disaster_
Management_Plan.pdf
Ipswich District Disaster Management Plan v1 https://www.police.qld.gov.au/RegionalPolici
HH
January 2019 ng/southern/Documents/IpswichDDMP.pdf
Splityard Creek Dam - EAP v12 Page 2Splityard Creek Dam - 2019/20 - i12
1.2 Abbreviations and acronyms
AEI Asset Engineer infrastructure O&M Operation & Maintenance
AEP Annual Exceedance Probability OB Observation Bore
AHD Australian Height Datum ORR Owners Regional Representative
AMTD Adopted Mean Thread Distance PAR Population at Risk
ANCOLD Australian National Committee on PFRM Predictive Flood Routing Model
Large Dams PMF Probable Maximum Flood
BOM Bureau of Meteorology PMP Probable Maximum Precipitation
CEO Chief Executive Officer PMPDF Probable Maximum Precipitation
CRA Comprehensive Risk Assessment Design Flood
CSE CS Energy PTD Physical Trading Desk
CSTN Counter Security & Terrorism Network QDMC Queensland Disaster Management
D/S Downstream Committee
DCF Dam Crest Flood QFES Queensland Fire & Emergency Services
DCL Dam Crest Level QPS Queensland Police Service
DDC District Disaster Coordinator RB Right Bank
DDMG District Disaster Management Group RDMG Relevant Disaster Management Group
DDMP District Disaster Management Plan RPEQ Registered Professional Engineer of
DDO Dam Duty Officer Queensland
DDS Director Dam Safety RSL Reduced Supply Level
DNRME Department of Natural Resources, SCTN Security & Counter Terrorism Network
Mines and Energy SDCC State Disaster Coordination Centre
DSR Dam Safety Regulator SDC State Disaster Coordinator
DSSP Dam Safety Services Provider SDCG State Disaster Coordination Group
DSTDM Dam Safety Technical Decision Maker SDF Sunny Day Failure
EAP Emergency Action Plan SES State Emergency Service
EA Emergency Alert SMS Short Message Service
EER Emergency Event Report SO Standby Operator
EGMAM Executive General Manager Asset SOP Standard Operating Procedure
Management (General Manager Asset SWL Storage Water Level
Operations, CleanCo) U/S Upstream
EGMPO Executive General Manager Plant WHS Workplace Health & Safety
Operations (Executive General WQ Water Quality
Manager Transition, CS Energy)
EL Elevation Level Wivenhoe Power Station
FCL Fixed Crest Level HDO Hydro Duty Officer
FSL Full Supply Level LEH Lead Engineer Hydro
IC Incident Coordinator PS Production Supervisor
IFHC Incremental Flood Hazard Category SMW Site Manager Wivenhoe
LB Left Bank WAM Wivenhoe Asset Management
LDMG Local Disaster Management Group WWE Wivenhoe Work Execution
LDMP Local Disaster Management Plan
MBP Manager Balance of Plant (Transitions
Project Manager, CleanCo)
Max. OL Maximum Operating Level
ME Manager Environment
MM Modified Mercalli
Splityard Creek Dam - EAP v12 Page 3Splityard Creek Dam - 2019/20 - i12
1.3 Business terms and definitions
Terms used in this section have the meaning as set out in accordance with relevant legislation or as defined by
operator requirements.
Term Definition
Dam Hazard Means a reasonably foreseeable situation or condition that may:
• cause or contribute to the failure of the dam, if the failure may cause harm to
persons or property
Dam Hazard Event Means an event arising from a dam hazard if:
• persons or property may be harmed because of the event, AND
• a coordinated response, involving the following relevant entities, is unlikely to be
required; local group and district group for the EAP, local government chief
executive, another entity the owner of the dam considers appropriate, AND
• the event is not an emergency event.
Disaster Management Of a district group or local government, means the group’s or local government’s
Plan (DDMP or LDMP) disaster management plan under the Disaster Management Act 2003.
District Group (DDMG) For an emergency action plan (EAP), means a district group established under the
Disaster Management Act 2003, section 22 whose disaster district under that Act
could, under the plan, be affected by a dam hazard.
Emergency Event Means an event arising from a dam hazard if:
• persons or property may be harmed because of the event, AND
• any of the following apply:
o a coordinated response, involving the following relevant entities, is likely to be
required; local group and district group for the EAP, local government chief
executive, another entity the owner of the dam considers appropriate, OR
o the event may arise because of a disaster situation declared under the Disaster
Management Act, OR
o an entity performing functions under the State disaster management plan
may, under that plan, require the owner of the dam to give the entity
information about the event.
Local Group (LDMG) For an EAP, means a local group established under the Disaster Management Act 2003,
section 29 whose local government area could, under the plan, be affected by a dam
hazard.
Notice Response A dam owner’s written response to a notice following an assessment of an EAP by a
local government or district group.
Referable Dam A dam, or a proposed dam after its construction, will be a referable dam if:
• a failure impact assessment of the dam, or the proposed dam, is carried out under
the Act, AND
• the assessment states the dam has, or the proposed dam after its construction will
have, a category 1 or category 2 failure impact rating, AND
• the chief executive has, under section 349 of the Act, accepted the assessment.
Also, a dam is a referable dam if:
• under section 342B of the Act, the owner of a dam is given a referable dam notice
and, before the effective day for the notice, does not give the chief executive a
failure impact assessment for the dam, AND
Splityard Creek Dam - EAP v11 Page 4Splityard Creek Dam - 2019/20 - i12
Term Definition
• the chief executive has not, under section 349 of the Act, accepted a failure impact
assessment of the dam.
Relevant Entity Means each of the following under the EAP for the dam:
• the persons who may be affected, or whose property may be affected, if a dam
hazard event or emergency event were to happen for the dam, e.g. the owners of
parcels of farm land adjacent to the dam or residents of a township
• local group and district group for the EAP
• local government whose local government area may be affected if a dam hazard
event or emergency event were to happen
• the chief executive
• another entity the owner of the dam considers appropriate, e.g. the Queensland
Police Service.
Terms consistent with Queensland Disaster Management Arrangements (reference C)
Activation Levels The four levels of EAP activation are:
• Alert – A heightened level of vigilance due to the possibility of an event
occurring. No further action may be required; however, the situation should
be monitored by someone capable of assessing the potential of the threat.
Moving to an Alert level indicates the dam owner is getting ready to activate
the Lean Forward level of the EAP if the situation deteriorates.
• Lean Forward – An operational state characterised by a heightened level of
situational awareness of an impending disaster event and a state of
operational readiness. Disaster coordination centres are on standby and
prepared but not activated.
• Stand Up – The operational state where resources are mobilised, personnel
are activated, and operational activities commenced. Disaster coordination
centres are activated. The dam owner needs to provide an ‘Emergency Event
Report’ (EER) in accordance with the provision of the Act.
• Stand Down – Transition from responding to an event back to normal core
business and/or continuance of recovery operations. There is no longer a
requirement to respond to the event and the threat is no longer present.
Notes:
The movement through these levels of activation is not necessarily sequential. It
should be applied with flexibility and adaptability and be tailored to the location and
event.
Triggering one of these levels of activation may not necessarily mean a similar
activation of the LDMG or DDMG.
Dam Crest The lowest elevation of the non-overflow crest section of the dam excluding handrails,
(reference D) parapets or wave walls that have not been designed to store water.
Dam crest flood The lowest elevation of the non-overflow crest section of the dam excluding handrails,
(reference D) parapets or wave walls that have not been designed to store water.
Dam Failure Dam failure is the physical collapse of all or part of a dam or the uncontrolled release
of any of its contents.
Downstream releases Downstream releases are outflows from the dam made through appurtenant
structures such as spillways or outlet works that are in accordance with the design of
the dam.
Splityard Creek Dam - EAP v11 Page 5Splityard Creek Dam - 2019/20 - i12
Term Definition
Earthquake A sudden release of energy in the Earth's crust or upper mantle, usually caused by
movement along a fault plane or by volcanic activity, resulting in the generation of
seismic waves that can be destructive. The potential consequences of an earthquake
include:
• settlement, sliding, or overturning of monoliths in the dam wall
• initiation of seepage lines in the foundations or abutments that could lead to piping
damage and potential inoperability of appurtenant works.
Flood Release A flood release from a dam occurs when catchment inflows raise the storage level
above the Full Supply Level (FSL) resulting in a discharge from the spillway of the dam.
Piping Internal scour caused by the water flow and seepage that occurs through earth dams,
dam foundations or dam abutments. The internal scour can lead to the formation of a
pipe which can lead to a failure of the dam.
Plane strike or other The impact of a plane, meteor or other high energy item on or in close vicinity of a
impact dam could damage the dam structure or create a wave that could overtop the dam.
Probable maximum The flood resulting from the probable maximum precipitation coupled with the worst
flood (reference E) flood-producing catchment conditions that can be realistically expected in the
prevailing meteorological conditions.
Probable maximum The theoretical greatest depth of precipitation for a given duration that is physically
precipitation possible over a particular drainage basin.
(reference E)
Probable maximum The flood resulting from the probable maximum precipitation coupled with typical
precipitation design catchment conditions.
flood (reference F)
Stability, main High foundation pore pressure peaks may reduce the Factor of Safety against slip
embankment dam circle failure to an unacceptable level.
‘Sunny day’ failure A failure that occurs at the FSL and there is no concurrent rain associated flooding.
(SDF)
Terrorist activity A deliberate attempt to damage, fail or contaminate a dam.
Splityard Creek Dam - EAP v11 Page 6Splityard Creek Dam - 2019/20 - i12
2. Introduction
2.1 Context
Under the Water Supply (Safety and Reliability) Act 2008 (the Act), the owner of a referable dam must have an
approved EAP for the dam. Referable dams, by definition, would put lives at risk if they were to fail.
This EAP has been prepared in accordance with Chapter 4 of the Act. The content requirements for EAPs are
contained in section 352H of the Act.
Summary of legal requirements – Section 352H
Section 352H(1) of the Act requires that the EAP must identify each dam hazard for the dam ;
and for each of these dam hazard types (e.g., flood operations, or chemical spill/toxic conditions):
1. identify the area likely to be affected by a dam hazard event or emergency event arising from the dam hazard;
and
2. identify each circumstance that indicates a material increase in the likelihood of the dam hazard event or
emergency event happening; and
3. state when and how the owner of the dam plans to warn persons who may be harmed, or whose property
may be harmed by an event caused by the dam hazard, if one happens, and/or there is a material increase in
the likelihood of an occurrence, including the order of priority in which the persons or categories of persons
are to be warned; and
4. state when and how the owner plans to notify the relevant entities for the dam, if a dam hazard event or
emergency event happens or, there is a material increase in the likelihood of such an occurrence, including
the order of priority in which the relevant entities are to be notified; and
5. state the actions the owner of the dam plans to take in response to a dam hazard event or emergency event.
In accordance with section 352H(2) of the Act, the EAP may provide for the dam owner to make arrangements
with a relevant entity for warnings to be given by the relevant entity on behalf of the dam owner in appropriate
circumstances.
Section 352HA of the Act states that before giving the chief executive an EAP, the owner of the dam must give a
copy of the plan to each local government whose area may be affected by a dam hazard identified in the plan;
and each district group for the plan.
Section 352HB of the Act states that the local government must assess the EAP for consistency with its disaster
management plan. In its assessment, the local government must consult with the local district group for the
plan.
Within 30 business days of receiving the EAP, the local government must give the owner of the dam a notice,
which states whether it considers the plan is consistent with its disaster management plan; and if not, give
reason why it considers the EAP is not consistent. The EAP must include any such notices, provided to the
owner of the dam by a local government (or district group); and any responses which the owner gives to these
notices. Section 352H(1) further stipulates that an EAP must include any other relevant matter prescribed by
regulation.
The local government whose area may be affected by a dam hazard for Splityard Creek Dam has been
determined as Somerset Regional Council. CS Energy has provided the Somerset Regional Council with a copy
of the draft EAP for assessment.
Section 352HC of the Act states that a district group may review the EAP for consistency with its disaster
management plan. The district group for Splityard Creek Dam is Ipswich DDMG. CS Energy has provided the
DDMG with a copy of the draft EAP for review.
Note: CS Energy has attempted to write the EAP to cope with all reasonably foreseeable emergencies. However, there is considerable uncertainty about
how any emergency might develop and progress. Factors such as the weather, the location, the mechanics, and the rate and size of any actual failure can
considerably affect any resulting flood discharges. Therefore, a significant number of assumptions have had to be made in compiling sections of the EAP.
Some variation in outcome should be expected where the event differs from the assumed behaviour.
Splityard Creek Dam - EAP v11 Page 7Splityard Creek Dam - 2019/20 - i12
2.2 Purpose
The purpose of this EAP is -
• to minimise the risk of harm to persons or property if a dam hazard event or emergency event for the dam
happens
• to identify dam hazards that could occur at Splityard Creek Dam and the area likely to be affected for each
hazard
• to prescribe emergency actions taken by the dam owners and operating personnel in identifying and
responding to dam hazards and notifying relevant entities.
It is possible for more than one dam hazard to exist at Splityard Creek Dam at the same time. In such a
circumstance, it may be necessary to act on the procedures within separate sections simultaneously.
The focus of this EAP is the management of dam hazards at Splityard Creek Dam by the owner of the dam
(CleanCo) and the communication and notification of dam hazards to the LDMG, DDMG and broader community.
However, the EAP sits within the broader emergency response framework. This EAP has been assessed and
considered to be consistent with a future inclusion in the Somerset LDMP.
2.3 Scope
The Splityard Creek Dam EAP covers -
• dam hazards evaluated within CS Energy’s Dam Safety Management Program
• details about the dam that are relevant to a dam hazard
• identification of circumstances that indicates a material increase in the likelihood of a dam hazard event or
emergency event
• triggers for activation of a tiered response to a dam hazard event or emergency event
• roles and responsibilities in responding to a dam hazard event or emergency event
• notification, warning, and communication protocols
• inspection, monitoring, and reporting protocols during emergencies (reference I)
• other relevant information that may assist with identifying the area affected by a dam hazard event or
emergency event
2.4 CS Energy/CleanCo provides training
Training of the use and implementation of this EAP document is carried out at various times throughout the year,
but specific pre-wet season training is undertaken at Wivenhoe Power Station (or convenient location of
stakeholders, i.e. Fernvale) in the months leading up to the wet season.
EAP training that is carried out on-site includes walkthroughs of new changes, scenario (role play) and Q & A to
check the knowledge and competency of all those who attended. This on-site training is presented to relevant CSE
staff (DDOs and ICs) and disaster management stakeholders. DSTDM information sessions are carried out once a
year with the same walkthrough of new changes and Q & A. New employees for EAP various roles will also have a
walkthrough of the EAP to understand soon after commencing work with CSE/CleanCo.
EAP training includes walkthroughs of new changes, scenario (role play) and Q & A to check the knowledge and
competency of all those who attended. This training is presented to relevant CSE/CleanCo staff (DDOs and ICs)
and disaster management stakeholders. DSTDM information sessions are carried out once a year with the same
walkthrough of new changes and Q & A for the Dam. New employees to the EAP various roles will have a
walkthrough and training on the EAP soon after they start work at CSE/CleanCo.
CSE/CleanCo is also working towards carrying out an EAP exercise annually involving each local authority and
disaster management stakeholders. This exercise would involve the SDCC and include the (non-live) testing of
Emergency Alerts.
Splityard Creek Dam - EAP v11 Page 8Splityard Creek Dam - 2019/20 - i12
2.5 Dam emergency organisation within CS Energy/CleanCo
The CS Energy emergency management framework generally utilises the organisation’s hierarchy and in-house
experts as illustrated in Figure 1 below.
Figure 1: CS Energy/CleanCo emergency response organisation
Key aspects of the emergency management framework are:
• Central to the framework is the role of IC for any dam hazard at a dam. The IC will maintain overall responsibility
for a coordinated response to the dam hazard incident.
• The IC is responsible for activating the EAP when the dam reaches an EAP activation level, unless instructed to
activate by the DSTDM who has determined that it is reasonable likely that the dam could reach an EAP
activation level. Should the IC be unavailable, the DDO is responsible for the activation. If the IC loses all
communications during a dam hazard, then as a fail-safe position, the DDO will assume the duties and
responsibilities of the IC. However, loss of communications could result in some communication processes
defined in this EAP not being carried out.
• CSE/CleanCo and/or its DSSP (includes DSTDM) and technical staff will provide technical advice to the IC and
DDO on an as needs basis. The DSTDM will also make flood and dam engineering decisions during a dam hazard.
These roles are filled by RPEQs (or by experienced engineers under the direct supervision of an RPEQ) and are
suitably qualified professionals as defined in reference J. Such advice will be provided within an established
framework of SOPs, models, standards and manuals.
2.6 Community information
Applying reference K, CSE/CleanCo with the assistance of the local council will ensure community education around
messaging and impacts of the EAP and its related events is undertaken and continually improved by incorporating
actions from lessons learnt (Section 2.7).
Splityard Creek Dam - EAP v11 Page 9Splityard Creek Dam - 2019/20 - i12 CSE/CleanCo provides information externally to customers, D/S residents and the community in a range of methods or channels in relation to Dam hazards and Emergencies. In future, individuals may be able to access information through Facebook, Twitter and the CleanCo web page. Immediately D/S residents are also provided information in text message/phone calls in the event of an activation of this EAP. In the event of an emergency event or when otherwise required, CSE/CleanCo and the affected Local Government will use the National Emergency Alert System to send a voice message and SMS in accordance with reference L. This service is provided by Telstra and managed by QFES at the SDCC. A copy of the CleanCo approved EAP is available to the public on the Business Queensland website, reference M. These copies are redacted to protect people’s personal details. 2.7 Lessons Learnt CSE/CleanCo will carry out Lessons Learnt workshops as part of its post event management. These Lessons Learnt can result in changes to the EAP. These will be captured and, if applicable to this document, will be implemented at the earliest opportunity and are made available in the next EAP update to the DSR as part of CS Energy’s continual improvement of its EAPs. The Lessons Learnt actions, if relevant, will be provided to stakeholders, such as the LDMG, DDMG, other dam owners and DNRME as appropriate. In addition, CSE/CleanCo requests any post event learnings be communicated regarding operational effectiveness and areas for improvement. 2.8 Downstream notification lists CS Energy has compiled the notification lists through an iterative process. At least annually, CS Energy confirms contact details for all landholders that are impacted in the downstream zones. 2.9 Comprehensive Risk Assessments A Comprehensive Risk Assessments (CRA) will be carried out on Splityard Creek Dam in the near future. This is a technical report that is utilised to ascertain risks for the dam as the basis for emergency triggers. The CRA will be made available to disaster management personnel whom require further assurance around the findings. To obtain a copy of a relevant CRA a request should be made in writing to CleanCo General Manager Asset Operations. It should detail the reason for the request and indicate who will be interpreting the data, i.e. engineering capability, for any unqualified personnel. Splityard Creek Dam - EAP v11 Page 10
Splityard Creek Dam - 2019/20 - i12
3. Roles and responsibilities
Roles and responsibilities Position holder 3
Owner (CleanCo, CS Energy interim Operator)
• Liaise with the Board and Minister CEO
• Activate CSE/CleanCo Crisis Management Procedure (reference N), if required EGMAM
• Ensure necessary resources are available to manage any event EGMPO
• Maintain an up to date list of immediately D/S residents (Appendix A4 and Appendix SMW
A5) of Splityard Creek Dam. The flood extent is indicated in the drawing in Appendix A7
• At all times, aim to provide timely advice and support to the LDMG in the affected local
government area and the DDMG in the affected disaster district
• During a dam hazard event that occurs with little or no warning, undertake the
following actions to ensure the community is informed as soon as possible:
o notify the residents listed in Appendix A4 and Appendix A5 via SMS
o contact SDCC Watch Desk to request an Emergency Alert campaign throughout
the Splityard Creek Dam Emergency polygon
o During a dam hazard event that occurs with adequate warning; notify the
residents listed in Appendix A4 and Appendix A5 via SMS, unless otherwise
agreed with the LDMG
• Record communications, notifications and observations as required
Owner’s Head Office Representative
• Authorise the issuing of EAP, SOPs and O&M Manual and Amendments MBP
• Facilitate Dam Safety Training Courses for CS Energy dam operations staff and other AEI
staff as appropriate, and ensure that all staff required to undertake Dam Safety work
are trained and accredited
• Ensure that risks identified in the CRA or other technical reports undertaken in relation
to Dam Safety are Included in the EAP
• Ensure visual inspections and instrumentation monitoring frequencies conform to
ANCOLD Guidelines
• Ensure all Dam Safety work orders, work instructions and lesson learned outcomes are
fully implemented
• Ensure requirements of the Dam Condition Schedule (reference P) are met
• Ensure the work instructions are correct and the Log Books, SOPs, Data Books, and
EAPs are reviewed annually as per reference P
• Ensure the 5 yearly Comprehensive Inspections and their Reports are completed by
suitably qualified personnel within the time specified in reference P and that work
orders are created for recommendations and work is undertaken as required
• Ensure Annual Inspections and their reports are completed by suitably qualified
personnel within the time frames specified in reference P and that work orders are
created for recommendations and work is undertaken as required
• Ensure the Dam Safety Instrumentation Data is reviewed and evaluated by suitably
qualified personnel to verify the structural integrity of the dams on a regular basis and
maintain a spread sheet for verification for audit and quality control
3 May be undertaken by one person, or jointly between the following personnel, depending on availability and/or emergency event
Splityard Creek Dam - EAP v11 Page 11Splityard Creek Dam - 2019/20 - i12
Roles and responsibilities Position holder 3
• Record communications, notifications and observations as required
Owners Regional Representative (ORR)
• Liaise with the Lead Engineer Hydro and Production Supervisor, WAM, WWE SMW
• Arrange dam specific training and accreditation for relevant staff LEH
• Ensure competent, trained and accredited personnel operate the storages PS
• Undertake the role of IC as required:
o Liaise with the Local Disaster Coordinator or proxy
o Activate the EAP, when necessary
o Ensure the EAP is implemented appropriately and carry out the IC role as
required
• Ensure all work orders, work instructions and lesson learned outcomes are fully
implemented.
• Record communications, notifications and observations as required
Dam Safety Technical Decision Maker (DSTDM)
• Analyse the situation and provide expert technical advice in relation to Dam Safety Various personnel
• Discuss Dam Hazard with peers and other technical experts and make sound decisions as per DSTDM
to mitigate the risk roster
• Determine response to incidents and emerging issues
• Issue warning on dam failure and advise on protective measures
• Ensure the EAP is implemented appropriately and carry out the DSTDM role as
required
• Liaise with DSR as required
• Record communications, notifications and observations as required
CleanCo Media Team
• Analyse sensitive issues, discuss with the Owner and issue media releases Various personnel
• Handle public and customer comments (including social media) and advise the Owner as per Media
if necessary Team roster
• Liaise with the IC and update QDMC of flood events
• Record communications, notifications and observations as required
Incident Coordinator (IC)
• Notify LDMGs, or councils if LDMGs not Stood Up, of intent to use the Emergency Alert SMW
(EA) LEH
• Activate the EAP, when necessary PS
• Ensure the EAP is implemented appropriately and carry out the IC role as required
• Arrange Situation Reports and determine frequency, as required
• Record communications, notifications and observations as required
Dam Duty Officer (DDO)
• Complete accreditation to operate and maintain relevant storage Various personnel
• Ensure the EAP is implemented appropriately and carry out the DDO role as required as per DDO roster
• Take direction from the DSTDM and IC as requested
• Arrange immediate site inspection and make informed assessment of the situation
Splityard Creek Dam - EAP v11 Page 12Splityard Creek Dam - 2019/20 - i12
Roles and responsibilities Position holder 3
• Escalate any issue not covered in the EAP or where actions are not clear
• Record communications, notifications and observations as required
Council
Councils have legislated local government functions, as per Section 80 of reference B. Somerset
These include: Regional Council
• Ensure it has a disaster response capability
• Approve its local disaster management plan
• Ensure information about an event or a disaster in its area is promptly given to the
DDMG for the disaster district in which area it is situated
• Perform other functions given to the local government under reference B
Queensland Police Service (QPS)
Manage the initial situation based on local operational procedures; including but not Local Police
limited to:
• Conduct emergency operations
• Coordinate and support CSE/CleanCo during a declared emergency at the dam
• Liaise with relevant organisations
• Evacuation of persons if required
• Control of essential traffic
• Security of specific area
Disaster Management Groups/Personnel –
(In addition to requirements outlined in reference B) LDMG
LDMG QFES
• As per IGEM review recommendation; work together with CSE/CleanCo and the DDMG
Council to ensure community education around messaging and impacts of EAP related
events is undertaken and continually improves
• Work with the Council and CSE/CleanCo to ensure the EAP is regularly exercised
• Identify and coordinate the use of resources and support services that may be required
for an EAP event, noting that for safety events unique to the dam, CSE/CleanCo will
approach councils to initiate
• During a dam hazard event, providing they are Stood Up, the LDMG in the affected
local government area will take the lead role in notifying the broader community
• Identify and provide advice to the relevant DDMG about support services required by
the LDMG to manage an EAP event
• Provide reports and make recommendations to the relevant DDMG about matters
relating to EAP events
QFES
• Work with dam owner and LDMG to ensure Emergency Alert polygons are prepared,
stored and tested at the State Watch Desk
And as per Section 352HC of the Act:
DDMG
• May review the EAP for consistency with the DDMP
Dam Safety Regulator (DSR)
Splityard Creek Dam - EAP v11 Page 13Splityard Creek Dam - 2019/20 - i12
Roles and responsibilities Position holder 3
• Liaison with relevant Minister on necessary actions DSR
• Approve this document as required under legislation
• Liaise with chief executive as required in administering (regulating) the Act
Splityard Creek Dam - EAP v11 Page 14Splityard Creek Dam - 2019/20 - i12
4. Dam details
4.1 General dam information
Location: Splityard Creek Dam is located approximately 70 km northwest of Brisbane on the Pryde Creek at a
distance of 8.6 km upstream from the confluence of Pryde Creek and the Brisbane River.
Purpose: Splityard Creek Dam is owned by CleanCo and operated by CS Energy under a transitional agreement. It
is the upper storage pond for a pumped storage hydroelectric facility.
Catchment: The catchment and upstream geography is only 3.6 km2 and is stable. Annual average rainfall is 1050
mm. Special consideration of upstream areas is not required.
Construction: The earth and rockfill dam was constructed in 1983 as an off-stream storage. A small saddle dam is
located on the northern side of the reservoir rim.
Specification: Table 2 below lists general specifications of Splityard Creek Dam.
Table 2: Splityard Creek Dam specifications
Description Specification
Dam type Zoned earth and rockfill embankment with central clay core
Full Supply Level (FSL) EL 166.5 m
Design Operating Range EL 133 m – EL 166.5 m
Dam Crest Level (DCL) EL 168.0 m
Storage capacity at FSL 28,700 ML
Storage area (at FSL) 104 ha
Maximum embankment height 76 m
Total length 1,120 m
Spillway type Open trapezoidal channel with a 1.0 m high concrete sill wall
control structure
Spillway crest level EL 166.5 m
Spillway crest width 190.4 m
Spillway Capacity at PMF (EL 167.6 m) 420 m3/s
Outlet works 28 m high intake tower with 900 mm MSCL outlet pipe
housed in a reinforced concrete outlet conduit
Outlet control 450 mm & 200 mm butterfly valves housed in the valve
house at the toe of main embankment
Minimum draw down level through outlet EL 108.5 m
works
Saddle Dam type Zoned earth and rockfill embankment with central clay core
Saddle Dam Crest Level EL 168.0 M
Saddle Dam length 159 m
Saddle Dam maximum height 10 m
All levels are to Australian Height Datum, AHD.
Conversion from State Datum is AHD (in metres) = State Datum RL (in feet) x 0.3048 - 0.03 m
Splityard Creek Dam - EAP v11 Page 15Splityard Creek Dam - 2019/20 - i12
4.2 Population at risk
In accordance with references Q, R and S:
• Splityard Creek Dam has a Category 1 Failure Impact Rating
• the estimated maximum PAR for a Sunny Day Failure (SDF) of Splityard Creek Dam is 47
4.3 Spillway adequacy and reservoir water releases
The spillway is not located near the dam wall. Water released via the spillway would only occur, if the
hydroelectric power station control system failed to stop the pumps, or in an extreme rainfall event when water is
not released through the Hydro Power Station. In these events, released water would be discharged into a gully
that flows via Branch Creek into Wivenhoe Lake, not into the original watercourse. There is a road bridge and
property along Branch Creek. However, a preliminary assessment indicated that the waterway area below the
bridge contains adequate capacity to pass any discharge from the spillway, either by a Power Station pumping
control failure or an extreme rainfall event. There are no buildings close to the waterway of Branch Creek;
therefore, there is no population at risk (PAR) for spillway discharge only.
Normal releases of water from the dam are through the power station into Wivenhoe Lake, not down the original
watercourse.
The outlet works consist of a 28 m high intake tower with a 900 mm MSCL outlet pipe housed in a reinforced
concrete outlet conduit, which passes through the main embankment dam. Water released via the outlet works
discharge pipe is not considered to constitute a credible hazard downstream, as the flow level in Pryde Creek
would be only marginally increased.
4.4 General arrangement
An aerial survey view of the dam is included in Figure 2. The general arrangement and other drawings are in
Appendix E.
Figure 2 Plan of the Splityard Creek Dam
Spillway
Saddle dam
Splityard
Creek Dam
storage
Wivenhoe
Dam storage
Main dam
Wivenhoe Hydro
Power Station
Splityard Creek Dam - EAP v11 Page 16Splityard Creek Dam - 2019/20 - i12
4.5 Emergency inspections and monitoring
The Splityard Creek Dam has been designed to conform to modern design standards, so that its failure is highly
unlikely. To maintain the dam in a safe condition and detect any dam hazard, as soon as it begins to develop, or
becomes apparent, the following is applicable to the Dam.
4.5.1 Inspections
• Routine Visual Inspection: Conducted as per reference FF or as directed by the DSTDM
• Detailed Inspection: Conducted annually
• Comprehensive Inspection: Conducted 5-yearly
4.5.2 Instrumentation and monitoring
To confirm the structural behaviour and safety of the embankment, the following Instrumentation was installed,
and is monitored, at Splityard Creek Dam:
• Water Level and seepage measurement
o 39 hydraulic piezometers to monitor pressure distribution through the embankment dam and its
foundations.
o 47 groundwater observation bores to monitor for any variations in the level of the phreatic
surface.
o 9 measuring weirs to monitor seepage from the embankment foundations and other parts of the
dam.
• Settlement/movement measurement
o 35 movement points used to monitor the embankment surface both vertically (Z direction) and
horizontally (X and Y directions).
o 4 inclinometers to monitor any movement within the embankment dam and/or its foundation.
o 8 extensometers installed in the core of the embankment where the axis deflects 37 degrees
upstream and passes over a high knob in the topography. The purpose of these extensometers
was to detect any movement of the embankment downstream, as well any transverse cracking
caused by differential settlement of the embankment across the knob.
The location of instrumentation and monitoring equipment is in the drawing in Appendix E.
Splityard Creek Dam - EAP v11 Page 17Splityard Creek Dam - 2019/20 - i12
5. Dam hazard – Piping: embankment, foundation or abutments
5.1 Overview
The emergency action described in this section relates to a potential dam failure hazard due to a piping condition
through the main embankment dam, foundations or abutments. An early indicator of a piping condition can be an
increase in seepage or a new area of seepage. If the seepage water is cloudy or has become cloudy this may
indicate that material is being transported and a pipe is being established.
If a pipe is established and progresses, then a dam failure may result. If a potential pipe is detected early remedial
repairs maybe possible in the form of constructing a filter and weighting zone over the pipe exit if safe to do so.
The area likely to be affected by this emergency event is described as:
• if dam failure does not occur then there will not be any area affected
• if dam failure does occur then the maximum area affected area is the level shown by the Sunny Day Failure
(SDF) line on the maps in Appendix B.
5.2 Emergency Actions
Table 3 to Table 6 specify emergency actions for the following roles:
• DDO
• IC
• DSTDM
Splityard Creek Dam - EAP v11 Page 18You can also read
