Climate Change Risk & Adaptation Action Plan - Wagga Wagga

Report for City of Wagga Wagga

Climate Change Risk & Adaptation Action Plan - Wagga Wagga 8 December 2017

Project Delivered for: Carly Hood - Manager Environment & City Compliance City of Wagga Wagga 243 Baylis Street (PO Box 20), Wagga Wagga NSW 2650 +61 2 6926 9342 - Hood.Carly@wagga.nsw.gov.au Project Delivered by: Joel Clayton - Senior Sustainability Consultant Edge Environment Level 5, 39 East Esplanade, Manly, NSW 2095, AUSTRALIA +61 (0)2 9438 0100 - joel@edgeenvironment.com.au

Revision

Revision Details

Author

Approved by

Date Approved

A

Initial issue for comment

Nicole Thompson & Joel Clayton

Tom Davies

08/12/2017

B

Integrated WWCC comments

Nicole Thompson & Joel Clayton

Tom Davies

22/01/2018

Executive Summary Wagga Wagga City Council (WWCC) is located in the Riverina region of NSW on the Murrumbidgee River. Wagga Wagga is the largest population centre in the Riverina region providing a central hub of services to a catchment of over 185,000 people.

Climate change is projected to impact upon this area, leading to potentially unforeseen risks to the built environment, with important economic, environmental and health implications. The development of a Climate Adaptation Plan (CAP) provides both operational and future recommendations that help to manage risks appropriately, ensuring the climate resilience of these assets into the future.

The objectives of this Climate Change Risk & Adaptation Plan are to: •

Provide an understanding of localised climate change projections for the Wagga Wagga LGA

•

Present a climate change risk analysis for the 10 selected WWCC assets

•

Develop an action plan of adaptation actions

A workshop was held with the selected Project Working Group (PWG) to review the likely climate change impacts and identify and assess risks to assets. The Council manages a range of different types of assets in the local area from amenities and sporting facilities to sewerage treatment plants (STP) and the Livestock Management Centre. Ten WWCC assets, as chosen by the PWG, were assessed. “Adaptation actions” required to treat significant risks were developed and then reviewed by the PWG after the workshop. Risks were then reassessed, considering the relevant adaptation actions, and given a revised risk rating.

A total of 38 climate change related risks to assets were identified in the risk workshop presented to WWCC PWG. These risks are associated with several common climate variables such as increase in hot days, increase in flooding and increased rainfall variability. An increase in hot days generated the most risks in the analysis, and were dominated by the impacts; pumping failures, infrastructure and vegetation damage, and an impact on public health. Increased rainfall variability and increased intensity of storm events also pose a high number of risks and impacts relating to maintaining STP processes, aquatic health, increased reliance on irrigation and sewer and detention basin overflows.

Increase in flooding and increased average temperature both have a number of similar impacts.

These risks and their adaptation actions were given a priority rating of low, medium and high derived from a rating score based on four factors; risk rating, asset renewal data, cost and practicality to implement. Table 1 provides a summary of the identified risks, their relevant adaptation actions, and their priority rating given for implementation and management of these risks.

Table 1 - Summary of adaptation actions required to achieve revised risk rating

Risk

Risk Rating

Adaptation action

Priority

Increased solar exposure for carparks and transit routes

Extreme

Increase urban canopy along transit routes and create refuge islands

High

Increased solar exposure for waiting areas

Extreme

Appropriate placement of pedestrian crossings and increase of urban canopy

High

Increased flooding to underground carparks

High

Upgrade pumping capacity

High

Increased UV intensity damaging vegetation

High

Develop tree replacement strategy for continued replacement and investment

High

Black outs and pump stops

Medium

Permanent generator per pump

High

Reduction in annual rainfall

High

Irrigation systems during establishment of vegetation

Medium

Degradation of parks and sporting grounds

High

Expand treated effluent irrigation and consider planning events in less vulnerable areas

Medium

Issues for animal welfare

High

Increase capacity for watering animals, provision of shade an education for stock transporters

Medium

Reduced viability of LMC

High

Consider diversification of income

Medium

Flooding and inundation of pumps

Medium

Inflow and infiltration prevention program

Medium

Sewer overflow

Medium

Periodically reassess storage redundancy

Medium

Localised flooding

High

Design bigger detention basins

Low

Increased algal growth and public health issues

High

Desilting, blackwater treatment plant

Low

Drying up of Lake Albert

High

Invest in alternative recreational assets

Low

Executive Summary .................................................................................................. 3 1

Introduction ........................................................................................................ 6 Objectives .............................................................................................................. 6 Sustainability targets............................................................................................. 6

2

Methodology ....................................................................................................... 7 Background research ............................................................................................ 7

3

Climate Analysis................................................................................................. 9 Historic climate for Wagga Wagga ....................................................................... 9 3.1.1

Temperature ..................................................................................................... 9

3.1.2

Rainfall ........................................................................................................... 10

3.1.3

Extreme weather events ................................................................................. 11

Climate change projections ................................................................................ 12

4

3.2.1

Average Temperature & Hot days ................................................................... 12

3.2.2

Rainfall ........................................................................................................... 12

3.2.3

Extreme weather events ................................................................................. 13

Risk Assessment and Adaptation Actions .................................................... 14 Risk Workshop..................................................................................................... 14 4.1.1

Workshop ....................................................................................................... 14

Risk assessment matrix ...................................................................................... 18 4.2.1

Risk Assessment outcomes ............................................................................ 19

Risk Summary and Evaluation ............................................................................ 25 Adaptation actions............................................................................................... 30 Prioritisation of adaptation actions .................................................................... 30

5

Recommendations ........................................................................................... 32

References .............................................................................................................. 33

1

Introduction

Future climate change poses significant risks to property and infrastructure through changes in temperature, rainfall and the increased occurrence or intensity of extreme weather events.

Understanding region-specific climate change projections provides an opportunity to assess these risks and develop management strategies and adaptation actions that reduce economic, environmental and social impacts associated with the asset.

Wagga Wagga is a major regional city in the Riverina region of NSW, which straddles the Murrumbidgee River and has an urban population of approximately 60,000. Climate change is projected to impact upon this area, leading to potentially unforeseen risks.

Wagga Wagga City Council (WWCC) manages many different assets in the local area which are at risk due to climate change impacts. 10 assets were chosen by the Project Working Group (PWG) to undergo a risk assessment. The development of a Climate Adaptation Plan (CAP) provides both operational and future recommendations that aim to ensure risks are managed appropriately, ensuring the climate resilience of these assets into the future.

Objectives The objectives of this CAP were: •

Provide an understanding of localised climate change projections for the Wagga Wagga LGA

•

Present a climate change risk analysis for the 10 asset types

•

Develop an action plan of adaptation actions

An example of the climate change projections visualised in map form is shown in Figure 1. It shows increase in days over 35oC in 2070 for NSW with Wagga Wagga’s increase indicated. Data is taken from NSW and ACT Regional Climate Modelling (NARCliM) Murray Murrumbidgee climate change snapshot (NSW OEH, 2017).

Figure 1 – Example of climate change projects – days over 35C 2070 (NARCliM)

Sustainability targets WWCC aims to develop a robust, relevant and up to date climate adaptation plan for the 10 selected assets to manage the risks associated with future climate change related impacts. The CAP will be used to summarise the work done during the Building Resilience to Climate Change project which received grant funding from Local Government NSW.

Wagga Wagga Climate Change Risk & Adaptation – 8 December 2017

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2

Methodology

This Climate Adaptation Plan (CAP) follows the ISO31000 Risk Management Process, and was designed to meet the requirements of the AS 5334 - Standard for climate change adaptation for settlements and infrastructure.

The risk assessment involved three key steps to develop risks and mitigation strategies collaboratively with key asset stakeholders. These steps are summarised below in Figure 2.

Climate and Context

Risk Analysis

Review of current risks

Review historic & best available climate projections

Multidisciplinary risk workshop

Review of asset operation and site location

Mitigation Strategies

Recommend design and operational mitigation strategies

Figure 2 – The collaborative climate change risk analysis process.

Background research Initially, Edge assessed Wagga Wagga site information and location to understand potential vulnerability to any climate related risks. This stage involved building an understanding of historic weather events, and analysing scaled down climate change projections for the relevant geographic area. Due to the potential for significant impacts on infrastructure and property, the following climatic variables were of key interest for the CAP: •

Extreme temperature

•

Rainfall (extreme precipitation and drought)

•

Flooding

•

Storm Intensity

Project Description Wagga Wagga City Council (WWCC) manages a number of different assets in the local area. 10 WWCC assets, as chosen by the Project Working Group (PWG), have been assessed for climate change risk and adaptation actions. The 10 WWCC assets that were chosen are detailed in the list below: 1. Sewer pumps 2.

Stormwater detention basins

3.

Sewage treatment plants

4.

Key pedestrian, cycling and recreational precincts

5.

Roads

6.

Schools

7.

Shopping centres

8.

Livestock Marketing Centre

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9.

Lake Albert/Wollundry Lagoon

10. Parks, ovals & gardens Even though WWCC doesn’t manage schools and shopping centres these assets were identified as key community infrastructure that are vulnerable to climate change and therefore were included in the risk assessment.

Figure 2 below shows all the assets that are assessed for this CAP. The output is from the Wagga Wagga Climate Vulnerability Explorer mapping tool that was developed for this project. All the coloured shapes and points indicate the above listed WWCC assets. The Wagga Wagga Climate Vulnerability Explorer will be delivered in conjunction with this report and is an additional source of information.

Figure 3 – Wagga Wagga Assets included in the CAP.

The Wagga Wagga Climate Vulnerability Explorer can be used to explore climate projections via an interactive map and historic weather data via interactive graphs for the Wagga Wagga area. Flood modelling, vegetation and social data is also visualised via the interactive map. For each of the 10 assets the climate change risk workshop results are included as pop up information.

A list of the information provided in the Wagga Wagga Climate Vulnerability Explorer tool is as follows: • Climate Projection – Increase in days over 35oC (2030, 2070) •

Climate Projection – Increase in maximum temperature (2030, 2070)

•

Climate Projection – Water Stress (Current, 2030)

•

Modelling – 1 in 100-year flood, 1 in 20-year flood depth, 1 in 100-year flood depth

•

Climate Projection – Change in rainfall, Summer & Winter (2030, 2070)

•

Modelling – Urban Canopy

•

Modelling – Vegetation areas

•

Climate Projection – Bushfire Risk increase (2030, 2070)

•

Modelling – Lone occupant households & low-income households

•

Zoning – Planning Zones

•

Historic data – Annual rainfall, daily rainfall, average rainfall

•

Historic data – Daily temperatures, heatwave days, solar exposure

•

Historic data – Wind speed & direction, severe storms by type

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3

Climate Analysis Historic climate for Wagga Wagga

3.1.1

Temperature

The Wagga Wagga region has a temperate climate with hot dry summers and cool to cold winters.

Summer temperatures in Wagga Wagga are warm averaging between 29oC and 32oC with maximum recorded of 45.2oC. Relative humidity however remains low in the summer months with a 3pm average of about 30%. The winters are cool to cold with overnight minimums averaging 3oC and daily maximums climbing to only 12oC to 14oC on average. Relative humidity is much higher in winter with a 3pm average of over 60% and a 9pm average just below 90%. Frost and fog are a feature of Wagga Wagga in winter. Snow has been recorded in the area but is a very rare occurrence. (BOM 2017).

Historical daily maximum and minimum temperatures for the region are displayed in Figure 4, with data from the Wagga Wagga AMO station (BOM ID: 072150). This station is close to the Wagga Wagga city centre (approximately 12.7 km), and has recorded weather data since 1941. The graphs below illustrate that annual maximum temperatures frequently exceed 35oC and 40oC (Figure 4).

Figure 4 – Daily Maximum and Minimum Temperatures – Wagga Wagga AMO Station

Heatwaves are defined as three or more consecutive days of hot weather over 35oC, and are of key concern due to their potential impacts upon infrastructure. Figure 4 below outlines the frequency of heatwaves at Wagga Wagga AMO for 1941-2017. Since 1941, on average there are 20.1 days above 35oC and 2.4 days above 40oC.

Wagga Wagga Climate Change Risk & Adaptation – 8 December 2017

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Figure 5 | Historic Annual heatwave days (Number of days above 35C or 40C that are 3 or more consecutively) – Wagga Wagga AMO station

3.1.2

Rainfall

Average annual rainfall for Wagga Wagga is approximately 572 mm, distributed relatively equally over the full 12 months (BOM 2017).

The BOM rain gauge at Wagga Wagga AMO (BOM ID 072150) has been collecting rainfall data since 1941. The highest recorded daily rainfall at this site was 110.6 mm on March 8th, 2010 (Figure 6). The average annual rainfall is shown in Figure 6 and shows the annual rainfall is quite variable for Wagga Wagga.

Figure 6 – Daily rainfall recordings at since 1941 show several large rainfall events – Wagga Wagga AMO station

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Figure 7 – Historic Annual Rainfall compared to Average Annual Rainfall – Wagga Wagga AMO station

3.1.3

Extreme weather events

Extremes of temperature and rainfall can have dramatic impacts upon infrastructure, and often occur during weather events that include storms, heat waves, droughts and bushfires. WWCC faces unique challenges related to extreme weather due to its scale, location and large variety of assets it manages.

The following climatic events have occurred in the project area and require consideration for the WWCC assets.

•

Droughts: Droughts are relatively common in the Wagga Wagga Region. Most recently, the Millennium Drought caused over a decade of dry conditions and is considered one of the most severe droughts ever recorded in the region (BOM, 2017).

•

Floods: Since the first rural settlement in the early 1840s there have been 77 floods of over 8.23m. Official records of Murrumbidgee River heights since 1891 read at the Hampden Bridge gauge are available and estimated records are available of rivers over 8.23m since 1844. Flooding of the City area in the south flood plain was frequent and to a lesser extent flooding occurred in the North Wagga Wagga village. There have been years of frequent floods, i.e. in one year 1974 Wagga Wagga had five floods all over 8.92 m and there was severe flooding in the 1950 to 1956 period. In other long periods 1939 to 1949 and 1960 to 1970 no floods occurred. Significant floods have occurred in Wagga Wagga in 1852, 1853, 1870, 1891, 1925, 1950, 1952, 1974, 1991 and 2012 with the largest recorded flood of 10.97 metres occurring in 1844. There have been two floods greater than the 1974 flood (WWCC, 2017)

•

Bushfires: The Wagga Wagga region is also prone to Bushfires, with the most recent event being the 2006 Pulletop bushfire, which killed 2,500 sheep, 6 cattle and destroyed 2 hay sheds and 50km of fencing (NSWRFS, 2006).

•

Hail & Severe storms: The Wagga Wagga region is also prone to hail and severe storm events (See Figure 7 for the record of severe storm events in the last decade for the Wagga Wagga region (BOM, 2017)).

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Figure 8 – Severe Storm Events for the Wagga Wagga region – (BOM Severe Storm Register, 2017)

Climate change projections Understanding future climate projections requires careful review of the most recent climate change emissions scenarios, and their related impacts on the climate system. Making use of scaled-down climate projections, it is possible to understand regionally-specific projections, which is more useful for conducting risk analyses on the built environment and infrastructure assets.

This study has been updated with the latest projections available from the CSIRO’s Murray Basin Cluster Report (CSIRO, 2015) and the NSW and ACT Regional Climate Modelling (NARCliM) Murray Murrumbidgee climate change snapshot (NSW OEH, 2017). CSIRO employed the Representative Concentration Pathways (RCP) emissions scenarios developed by the International Panel of Climate Change (IPCC) in their Fifth Assessment Report (AR5). These scenarios model climate change according to different economic growth, population, energy consumption and land use change trajectories over the next century.

The timescales selected for the NARCLiM and predominately used in this CAP are the following: •

1990 to 2009 (base),

•

2020 to 2039 (near future - 2030), and

•

2060 to 2079 (far future - 2070)

Analysis of projected climate changes involved summarising the key impacts that are likely to arise due to a changing climate. Temperature, rainfall and extreme weather events are of key concern due to their potentially significant impacts on the WWCC assets. Climate projections are described below, and are summarised in Table 2.

3.2.1

Average Temperature & Hot days

From NARCliM climate projections the number of days over 35°C are predicted to: •

increase by 9 days for 2030 and

•

increase by 25 days for 2070

The climate projections also predict that the maximum temperature will:

3.2.2

•

increase by 2.03°C for 2030 and

•

increase by 3.7°C for 2070

Rainfall

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The NARCliM climate projections predict that the Summer (Dec-Feb) rainfall will: •

increase by 5.3mm for 2030 and

•

increase by 14.6 mm for 2070

Conversely the climate projections predict that Winter rainfall (Jun-Aug) will:

3.2.3

•

decrease by 0.8mm for 2030 and

•

decrease by 1.5mm for 2070

Extreme weather events

Future climate change is likely to increase the intensity and severity of extreme climatic events.

Importantly, the relationship between climatic averages and the frequency of extreme events is often non-linear, illustrated by climate projections that associate dramatic increases in very hot days with small increases in mean temperature (AGO 2006). This makes the development of reliable projections for extreme events such as storms and droughts very difficult. Key extreme climate projections are discussed in the following sections.

•

Droughts: Droughts are a common feature of the South-East Australian climate, and are likely to continue to be so under a changing climate. However, there is low confidence in predicting changes in the frequency and longevity of extreme droughts in the future. There is medium confidence that under a high emissions scenario, the Murray Basin region is likely to experience increased time under drought conditions (CSIRO 2015).

•

Storms and extreme rainfall: There is high confidence that the intensity of rainfall will increase under a changing climate but, as with mean rainfall projections, the scale of these changes is difficult to predict (CSIRO 2015).

•

Fire weather: From NARCliM projections, Bushfire risk via the Forest Fire Danger Index is predicted to increase by 0.5 by 2030 and increase by 0.98 by 2070.

Table 2 – Wagga Wagga Climate Change projections, Key climate variables (2030 and 2070) compared to annual averages

Variable

Baseline (19902009)

Units

Temperature – average annual maximum

22.2oC

o

Temperature – Hot Days

20.1

Rainfall – Annual mean

Near Future (2030)

Far Future (2070)

+ 0.9oC

+ 3.7oC

Average days over 35oC per year

+9

+ 24

572.6 mm

mm

Summer: +5.3mm Winter: -0.8mm

Extreme rainfall

NA

NA

Bushfire Risk Index

10

Forest Fire Danger Index (FFDI)

C

Summer: +14.6mm Winter: -1.5mm High confidence in increased intensity of rainfall under both scenarios, however magnitude of this change is uncertain. + 0.5

Wagga Wagga Climate Change Risk & Adaptation – 8 December 2017

+ 0.98

References

(NSW OEH, 2017) (NSW OEH, 2017) (NSW OEH, 2017) CSIRO (2015)

(NSW OEH, 2017)

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4

Risk Assessment and Adaptation Actions Risk Workshop

Climate change risks to Wagga Wagga City Council and their associated adaptation actions were identified through a workshop held on the 31st of July 2017. Workshop attendees included stakeholders representing a multidisciplinary skill set across Council. The attendees of the workshop are listed in Table 3.

Table 3 – CCAP Workshop attendees.

Name

Company

Title

Michael Gleeson

Wagga Wagga City Council

David Read

Wagga Wagga City Council

Lisa Saffery

Wagga Wagga City Council

Alice Kent

Wagga Wagga City Council

Glenda Pym

Wagga Wagga City Council

Jason Carroll

Wagga Wagga City Council

Stephen Jewell

Wagga Wagga City Council

Chris Breen

Wagga Wagga City Council

Joel Clayton

Edge Environment

Senior Sustainability Consultant

Jessica Lethbridge

Edge Environment

Information Systems Specialist

Ken Lunty

Edge Environment

Principal Sustainability Consultant

4.1.1

Workshop

The workshop presentation established the context of climate change and its potential impacts on the Wagga Wagga Local Government Area (LGA). It introduced project stakeholders to climate change projection scenarios, and encouraged them to consider climate change impacts in the context of their LGA. Risks resulting from these impacts were then developed and recorded, considering both direct and indirect risks to WWCC LGA, its assets, users and any other relevant stakeholders. Each risk was then evaluated and rated in terms of likelihood and consequence using the risk matrix presented in Table 4 and Table 5.

4.1.2

Risk Assessment Framework

To assess identified risks systematically, a likelihood scale was used to determine how likely a risk was to occur, followed by consequence assessment. These scales are aligned with the WWCC risk assessment criteria. Likelihood ratings are described for both recurring and single event risks in Table 4.

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Table 4 - Example Likelihood Scales (AGO 2007).

Rating

Description

Quantification

Almost certain

The event is expected to occur in normal circumstances. There has been frequent history.

At least once every 1-6 months

Likely

The event will probably occur in most circumstances. Some recurring past event history

Once every 6-12 months

Possible

The event could occur sometimes. Some past warning signs or previous event history

Once every 1-5 years

Unlikely

The event could occur in some circumstances

Once every 5-10 years

Rare

May only occur in exceptional circumstances.

Once every 10 years or more

4.1.3

Consequence

Consequence is an assessment of the severity of the risk’s impacts should it occur. Consequence assessment included several success categories in line with the WWCC risk assessment criteria (Table 5).

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Table 5 - WWCC Consequence Scale

Financial

Catastrophic

Major

Moderate

Significant/ material financial loss over $1 million

Major financial loss of $100,000 to $1 million

High financial loss of $50,000 to $100,000

Governance

Significant regulatory breach/s including court proceedings

Significant regulatory breach/s

Moderate regulatory breach

Community and Reputational

Widespread total degradation of operations and services Extreme adverse public/staff reaction and/or major widespread negative publicity

Major degradation of services and operations.

Major adverse public/staff reaction and/or significant negative publicity

Moderate degradation of services and operations.

Moderate adverse public/staff reaction and/or moderate negative publicity

Wagga Wagga Climate Change Risk & Adaptation – 8 December 2017

Strategic

The project will completely stop Delivery of objectives cannot be achieved

Key parts of project will be delayed more than a month Major impact that threatens delivery of objectives

Key parts of the project will be delayed more than a week Moderate impact to agreed delivery of objectives

Environmental

Significant environmental impact, EPA intervention including significant fines

Operational

Health & safety

Severe impact to staff availability

Kill or cause permanent disability or ill health

Significant procurement impact/loss, including serious breach of probity Widespread systems / records management outage declared for an extended period beyond the Maximum Acceptable Outage time Major impact to staff availability

Major environmental impact, EPA intervention

Major impact/loss resulting from procurement processes, including breach of probity

Long term illness or serious injury

Loss of system access or access to records for an extensive period

Moderate environmental impact handled internally

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Moderate impact to staff availability Moderate impact/loss resulting from procurement processes

Medical attention and several days off work

Financial

Governance

Community and Reputational

Strategic

Environmental

Operational

Health & safety

Loss of system access or access to records for a prolonged period

Minor

Minor financial loss of Operations - $5,000 to $50,000

Minor regulatory breach

Capital $10,000 to $50,000

Insignificant

Low financial loss of up to: Operations $5,000 Capital $10,000

Minor degradation of services and operations.

Minor adverse public/staff reaction and/or minor negative publicity

No degradation of services.

No regulatory breach

No adverse public/staff reaction and/or negative publicity

Wagga Wagga Climate Change Risk & Adaptation – 8 December 2017

Some delay anticipated to project delivery Minor impact to agreed delivery of objectives

A very small delay anticipated to project delivery Negligible impact to agreed delivery of objectives

Minor impact to staff availability Minimal environmental impact handled internally

Minor impact/loss resulting from procurement processes Minor impacts resulting from loss of system access or access to records Negligible impact to staff availability

No environmental impact

Insignificant impact/loss resulting from procurement processes Insignificant impacts results from system interruptions

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First aid treatment needed

No injury to persons

Risk assessment matrix Risk likelihood and consequence were then combined using the risk assessment matrix in Table 6, leading to the systematic development of a risk rating used to prioritise risk management strategies.

Table 6 - Risk Assessment Matrix (AGO 2007)

Insignificant

Minor

Moderate

Major

Catastrophic

Almost Certain

Medium

Medium

High

Extreme

Extreme

Likely

Low

Medium

High

High

Extreme

Possible

Low

Medium

Medium

High

High

Unlikely

Low

Low

Medium

Medium

Medium

Rare

Low

Low

Low

Low

Medium

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4.2.1

Risk Assessment outcomes

The following table describes the risks identified in the workshop, including the risk statement (outlining the risk’s cause and effect), the asset the risk may impact, its likelihood, consequence and subsequent risk rating, should it occur. Results of the stakeholder review are also incorporated, providing the adaptation actions and revised risk level.

Table 7 – Risk Assessment outcomes.

Climate Impact

Asset

Increase in hot days Shopping Centres

Increase in hot days Schools

Risk Statement (Cause and Effect) Increased solar exposure in carparks and transit routes, causing heat exhaustion, stroke, skin conditions causing increased public health costs and decreased use of facilities. (particularly disabled or lower income individuals without access to cars) Increased solar exposure on transit routes and waiting areas, causing heat exhaustion, heat stroke and skin conditions causing increased public health costs. (particularly disabled or lower

Likelihood

5-Almost Certain

5-Almost Certain

Wagga Wagga Climate Change Risk & Adaptation – 8 December 2017

Consequence

4-Major

4-Major

Level of Risk

Adaptation actions

Residual Likelihood

Residual Consequence

Level of Risk

Extreme

Creation of refuge islands, increase of urban canopy along transit routes. Shading of carparks.

3-Possible

2-Minor

Medium

Extreme

Creation of refuge islands, increase of urban canopy along transit routes.

Appropriate placement of pedestrian crossings for busy times of day

3-Possible

2-Minor

Medium

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Climate Impact

Asset

Risk Statement (Cause and Effect)

Likelihood

Consequence

Level of Risk

Residual Likelihood

Residual Consequence

Level of Risk

High

Implement inflow and infiltration prevention program with more resources.

4-Likely

1-Insignificant

Low

High

Design bigger detention basins to 1 in 20 years.

Build bigger pipes.

Change building laws so new buildings can deal with flooding.

5-Almost Certain

2-Minor

Medium

High

Design bigger detention basins to 1 in 20 years.

Build bigger pipes.

Change building laws so new buildings can deal with flooding

5-Almost Certain

2-Minor

Medium

Adaptation actions

income individuals without access to cars)

Increased rainfall variability Sewage Treatment Plants

Increased flooding Stormwater Detention Basins

Increased rainfall variability

Stormwater Detention Basins

Increased rainfall intensity, leading to varying volumes of water to deal with, consequence is more trouble maintaining STP process conditions (bugs etc‌) causing extra costs and reseeding of WTP Increased flooding, leading to more water volume than detention basin can hold, causing overflow of surrounding area (localised flooding) Increased rainfall intensity, leading to more water volume than detention basin can hold, overflow of surrounding area (localised flooding)

4-Likely

5-Almost Certain

5-Almost Certain

Wagga Wagga Climate Change Risk & Adaptation – 8 December 2017

4-Major

3-Moderate

3-Moderate

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Climate Impact

Increased intensity of storm events

Asset

Stormwater Detention Basins

Increased flooding Shopping Centres

Increase in hot days Shared Paths

Risk Statement (Cause and Effect) Increase intensity of storm events, leading to more water volume than detention basin can hold, overflow of surrounding area (localised flooding) Increased Flooding, leading to inundation of lower levels restricting access to centres due to failure to drain, encouraging mosquitos and stopping access to facilities increased Solar exposure, leading to more UV intensity for vegetation, causing aging tree canopy needing removal earlier than expected and may expose currently protected paths and streets making current safe routes less accessible and

Likelihood

5-Almost Certain

4-Likely

5-Almost Certain

Wagga Wagga Climate Change Risk & Adaptation – 8 December 2017

Consequence

3-Moderate

4-Major

3-Moderate

Level of Risk

Adaptation actions

Residual Likelihood

Residual Consequence

Level of Risk

High

Design bigger detention basins to 1 in 20 years.

Build bigger pipes.

Change building laws so new buildings can deal with flooding

5-Almost Certain

2-Minor

Medium

High

Upgrades to pumping capacity, change DCP to restrict underground carpark

3-Possible

3-Moderate

Medium

High

continual replacement and increased investment, develop tree replacement strategy to prevent removal without replacement

2-Unlikely

2-Minor

Low

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Climate Impact

Asset

Risk Statement (Cause and Effect)

Likelihood

Consequence

Level of Risk

Adaptation actions

Residual Likelihood

Residual Consequence

Level of Risk

2-Unlikely

2-Minor

Low

exposing pedestrians

Increased rainfall variability

Increased intensity of storm events

Shared Paths

reduction in annual rainfall, causing increased irrigation needs which increases costs

4-Likely

3-Moderate

High

Water-efficient irrigation systems during establishment & consider water-efficient tree selection

Sewer Pumps

Increased storm events, leading to black outs, causing pump stops and sewer overflow.

3-Possible

3-Moderate

Medium

Permanent generator per pump.

3-Possible

1-Insignificant

Low

Sewer Pumps

Increase in hot days leading to black outs, causing pump stops and sewer overflow.

3-Possible

3-Moderate

Medium

Permanent generator per pump.

3-Possible

1-Insignificant

Low

Increase in hot days

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Climate Impact

Asset

Risk Statement (Cause and Effect)

Likelihood

Sewer Pumps

Increased flooding, leading to inundation of pumps, causing potential health impacts and environment impacts (EPA)

2-Unlikely

Sewer Pumps

Increased rainfall intensity, leading to inundation, causing pumps to pump more volume and use more electricity and therefore cost more to run.

5-Almost Certain

Sewage Treatment Plants

Increased flooding, leading to inundation, causing more volume of water to be treated and therefore more electricity costs.

Increased flooding

Increased rainfall variability

Increased flooding

Increased flooding Sewage Treatment Plants

Increased flooding, leading to inundation, causing a larger volume of water to be treated triggering the bypass activation therefore

3-Possible

3-Possible

Wagga Wagga Climate Change Risk & Adaptation – 8 December 2017

Consequence

3-Moderate

2-Minor

2-Minor

2-Minor

Level of Risk

Residual Likelihood

Residual Consequence

Medium

Implement inflow and infiltration prevention program with more resources.

2-Unlikely

2-Minor

Low

Medium

Implement inflow and infiltration prevention program with more resources.

5-Almost Certain

2-Minor

Medium

Medium

Implement inflow and infiltration prevention program with more resources.

3-Possible

1-Insignificant

Low

Medium

Implement inflow and infiltration prevention program with more resources.

3-Possible

1-Insignificant

Low

Adaptation actions

Level of Risk

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Climate Impact

Asset

Risk Statement (Cause and Effect)

Likelihood

Consequence

Level of Risk

3-Possible

2-Minor

Medium

4-Likely

2-Minor

Medium

Residual Likelihood

Residual Consequence

Level of Risk

Reassess storage redundancy periodically (every 5 years)

3-Possible

2-Minor

Medium

Reassess storage redundancy periodically (every 5 years)

4-Likely

2-Minor

Medium

Adaptation actions

untreated water leaving the STP can result in environment and health issues, EPA fines and reputational issues

Increased intensity of storm events

Sewage Treatment Plants

Increase in hot days Sewage Treatment Plants

Increased intensity of storm events, leading to black outs, causing water treatment to stop and sewer overflow, resulting in sewer flow into the river untreated (health issues & EPA fines).

Increase in hot days, leading to black outs, causing water treatment to stop, sewer untreated overflow into the river, health issues and EPA fines

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The following table describes the risks identified in the workshop, however these climate impacts did not have an adaptation action assigned.

Table 8: Risk Assessment Outcomes without Adaptation Actions Climate Impact

Asset

Increased flooding

Risk Statement (Cause and Effect)

Increased flooding, leading to more water volume than detention basin can hold, causing detention basins to be increased resulting in a large Cost of building bigger detention basins.

Likelihood

Cons eque nce

Level of Risk

5-Almost Certain

5Catas trophi c

Extreme

Recreational Water Bodies

Warmer weather, encouraging algal growth, causing possible health issues for people/pets using the lake

4-Likely

3Mode rate

High

Recreational Water Bodies

Increased in hot days, leading to Lake drying up and fish dying, causing no recreational area for community and resulting amenity decline

3-Possible

4Major

High

Parks

Decrease in rainfall, leading to degradation of parks, grounds etc, causing decreased economic productivity

3-Possible

4Major

High

Livestock Marketing Centre

Increase in hot days, leading to Animal welfare being affected while animals are in the centre/transported to the centre leading to Handling of thirsty stock potentially causing animal death, sickness and damaged reputation

3-Possible

4Major

High

Livestock Marketing Centre

Increase in hot days, leading to Animal welfare being affected while animals are in the centre/transported to the centre, leading to Handling thirsty stock, Causing animal death or

3-Possible

4Major

High

Stormwater Detention Basins

Increase in hot days

Increase in hot days

Increased rainfall variability

Increase in hot days

Increase in hot days

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sickness and economic flow on effects

Increase in hot days Livestock Marketing Centre

Increase in hot days, leading to a downturn in regional farming industry leading to reduced viability of the LMC

Shared Paths

Increased solar exposure on paths, leading to the surface heat, causing damages the pathway increasing cost to replace or repair

Increase in hot days

Increase in hot days Shared Paths

Increased flooding Recreational Water Bodies

Increase in hot days Recreational Water Bodies

Increased rainfall variability

Recreational Water Bodies

Increased solar exposure on paths, leading to extreme heat of paths, which discourages use reducing accessibility by trapping those who only have the option to walk or cycle (particularly disabled or lower income individuals without access to cars) Increased Flooding resulting in erosion leading to silting of lake, road destabilisation in the catchment area. This can lead to increased costs associated with maintenance Increase in hot days, leading to Lake drying up/algal bloom and fish dying, causing no recreational area for community and cancellation of events and financial loss Decrease in rainfall, leading to Lack of water, causing reduced biodiversity and

3-Possible

5Catas trophi c

High

4-Likely

2-Minor

Medium

4-Likely

2-Minor

Medium

4-Likely

2-Minor

Medium

5-Almost Certain

2-Minor

Medium

3-Possible

3-Moderate

Medium

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reduced local amenity

Recreational Water Bodies

Decrease in rainfall, leading to a lack of water for irrigation, causing a switch to town water supply.

(Wollundry Lagoon)

3-Possible

2-Minor

Medium

Parks

Decrease in rainfall, leading to Increased irrigation demand for parks, grounds etc, causing increased costs

3-Possible

3-Moderate

Medium

Parks

Decrease in rainfall, leading to degradation of parks, grounds etc, causing lost income from parks, event, hire fees

3-Possible

3-Moderate

Medium

Parks

Increase in average temperatures, leading to an Increase in weed/pest species, causing increased maintenance costs

3-Possible

3-Moderate

Medium

Parks

Decrease in rainfall, leading to Parks/ovals being phased out during long periods of drought, causing loss of community use

2-Unlikely

3-Moderate

Medium

Livestock Marketing Centre

Heavy rainfall events, leading to localised flooding, causing pathogens from animal faeces to enter surrounding areas and groundwater

2-Unlikely

3-Moderate

Medium

Increased rainfall variability

Increased rainfall variability

Increased rainfall variability

Increased average temperature

Increased rainfall variability

Increased rainfall variability

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Increased average temperature Livestock Marketing Centre

Increase in hot days Sewage Treatment Plants

Increased rainfall variability Parks

Increase average temperature, leading to an increase in animal diseases and transfer onto humans, causing animal and staff health issues Increase in hot days, leading to higher operating temperature, causing increased odour issues for community, reputational issues Decrease in rainfall, leading to degradation of parks, grounds etc, causing safety issues associated with ground quality

2-Unlikely

4-Major

4-Likely

1-Insignificant

Low

3-Possible

1-Insignificant

Low

Wagga Wagga Climate Change Risk & Adaptation – 8 December 2017

Medium

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Risk Summary and Evaluation A total of thirty-eight climate change related risks to assets were identified in the risk workshop and presented to WWCC PWG. These risks are associated with several common climate variables. An increase in hot days generated the most risks in the analysis, and were dominated by the following impacts: pumping failures, infrastructure and vegetation damage, and an impact on public health.

Increased rainfall variability and increased intensity of storm events also pose a high number of risks and impacts relating to maintaining STP processes, aquatic health, increased reliance on irrigation and sewer and detention basin overflows. Increase in flooding and increased average temperature both have a number of similar impacts. The variables and key impact areas for Wagga Wagga City Council are summarised in Table 9 below.

Table 9 – Climate variables and their key climate impacts.

Climate variable

Number of risks

Increase in hot days

14 Increased rainfall variability

12 Increased intensity of storm events

9 Increased flooding

7 Increased average temperature

2

Focus impact areas •

Blackouts and pumping failures

•

Public health impact

•

Infrastructure damage

•

Biodiversity and vegetation damage

•

Issues maintaining STP process conditions

•

Aquatic health issues i.e. algal growth, drought

•

Increased reliance on irrigation

•

Reduced use of facilities, loss of income

•

Blackouts and pumping failures

•

Sewer overflows

•

Overflowing of detention basins

•

Erosion or silting of lake

•

Infrastructure damage

•

Public health impacts

•

Increase in weed/pest species

•

Increase in disease

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Adaptation actions Post-workshop evaluation with participants generated adaptation actions for each risk through asset changes or operational management. The key aim was to reduce the risk rating by suggesting strategies that could remove the risk or reduce its impacts.

The list of revised risks was then circulated through the workshop participants, who verified the adaptation measures and revised the risk ratings. The final risk counts are identified in Figure 9 below.

Through this method, two extreme risks were reduced to high risk, seven high risks were reduced to medium risk, and eight high or medium risks were reduced to low.

Comparison of risk before and after adaptation actions 25

20

15

10

5

0 Workshop risk assessment Low risk

Medium risk

Final risk review High risk

Extreme risk

Figure 9 – Graph showing risk assessment at workshop and revised risks with adaptation actions

Prioritisation of adaptation actions To develop an action plan that prioritises the adaptation actions for implementation, each adaptation action was given a priority rating score. The rating score was based on four factors; initial risk rating, asset renewal date, cost and practicality to implement. See the following (Table 9 and 10) for the prioritisation categories and weighted scoring.

Table 10 - Scoring factors for priority rating

Level of Risk

Asset Renewal Date

Cost ($) Indication to implement Action

Practicality of Action

Low

Short term - Up to 5 years

Low: $0-$50,000

Simple: Minimal project management and procurement process

Medium

Medium term - 5 to 10 years

Medium: $50,000 $500,000

Moderate: Some complexity, requires RFQ and >40hours of Project Management

High

Long term - More than 10 years

High: >$500,000

Complex: requires tender and dedicated project manager

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Each adaptation action was given a score individually from 1 to 4 for each of the four factors; initial risk rating, asset renewal date, cost and practicality to implement see Table 11. Each of the four factors are weighted differently to give a final score to determine the total priority score.

The total priority score is then sorted into band ranges to give an overall priority rating (Table 11). The higher the score, the higher the priority rating.

2

Medium

2

2

High

3

2

Extreme

4

2

Weight

Practicality of Action

3

1

Low: $0$50,000

3

1.5

Simple

3

1

2

1

Medium: $50,000 $500,000

2

1.5

Moderate

2

1

Long term More than 10 years

1

1

High: >$500,000

1

1.5

High

1

1

Score

Short term Up to 5 years Medium term - 5 to 10 years

Score

Weight

1

Cost ($) Indication to implement Action

Score

Low

Weight

Asset Renewal Date

Weight

Level of Risk

Score

Table 11 - Four factors score and weighting

Table 12 - Min - Max score range for priorities

Min range Score

Max range score

Priority Rating

5.5

9.8

Low Priority - Implement when funding is available

9.8

14.2

Medium Priority- Implement with next renewal

14.2

18.5

High priority - Implement ASAP

The ‘WWCC Risk and Adaptation Action Plan’ spreadsheet has been provided to Wagga Wagga City Council. Worksheet ‘AA Prioritisation’ includes drop down boxes that allow you to change the factors and the scores for each adaptation, and will automatically change the priority rating accordingly.

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5

Recommendations

This section of the CAP sets out the prioritised adaptation actions for Wagga Wagga City Council to successfully mitigate and manage the risks identified through the risk analysis process. Many of the actions require planning, costing and strategic placement into asset renewal and operational plans to ensure risks are managed appropriately. Table 13 below sets out the risks, their relevant adaptation actions, and priority rating given for implementation and management of these risks. The priorities, derived from the method outlined in section 4.5 above are as follows: •

High priority - Implement ASAP

•

Medium priority- Implement with next renewal

•

Low priority - Implement when funding is available

Table 13 - Summary of adaptation actions required to achieve revised risk rating

Risk

Risk Rating

Adaptation action

Priority

Increased solar exposure for carparks and transit routes

Extreme

Increase urban canopy along transit routes and create refuge islands

High

Increased solar exposure for waiting areas

Extreme

Appropriate placement of pedestrian crossings and increase of urban canopy

High

Increased flooding to underground carparks

High

Upgrade pumping capacity

High

Increased UV intensity damaging vegetation

High

Develop tree replacement strategy for continued replacement and investment

High

Black outs and pump stops

Medium

Permanent generator per pump

High

Reduction in annual rainfall

High

Irrigation systems during establishment of vegetation

Medium

Degradation of parks and sporting grounds

High

Expand treated effluent irrigation and consider planning events in less vulnerable areas

Medium

Issues for animal welfare

High

Increase capacity for watering animals, provision of shade an education for stock transporters

Medium

Reduced viability of LMC

High

Consider diversification of income

Medium

Flooding and inundation of pumps

Medium

Inflow and infiltration prevention program

Medium

Sewer overflow

Medium

Periodically reassess storage redundancy

Medium

Localised flooding

High

Design bigger detention basins

Low

Increased algal growth and public health issues

High

Desilting, blackwater treatment plant

Low

Drying up of Lake Albert

High

Invest in alternative recreational assets

Low

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References AGO. (2006). Climate Change Impacts and Risk Management - A Guide for Business and Government. Canberra: Australian Greenhouse Office - Commonweath of Australia.

Bewsher Consulting. (2010). Macquarie Park Floodplain Risk Management Study & Plan. City of Ryde.

Bradstock, R., Davies, I., Price, O., & Cary, G. (2008). Effects of climate change on bushfire threats to biodiversity, ecosystem processes and people in the Sydney region. New South Wales Department of Environment and Climate Change.

CSIRO. (2015). East Coast Cluster Report, Climate change in Australia Projections for Australia's Natural Resource Management Regions. CSIRO and Mureau of Meterology.

IPCC. (2007). Climate Change 2007: Synthesis Report. International Panel on Climate Change.

National Climate Change Adaptation Research Facility (NCCARF). (2010). Case study: Impacts and adaptation responses of infrastructure and communities to heatwaves. NCCARF. NSW OEH. (2014). Metropolitan Sydney Climate Change Snapshot. Sydney: Office of Environment and Heritage.

NSW OEH. (2014). New South Wales Climate Change Snapshot. Sydney: NSW Office of Environment and Heritage.

NSW OEH. (2017, June 14). AdaptNSW. Retrieved from About NARCLiM: http://climatechange.environment.nsw.gov.au/Climate-projections-for-NSW/About-NARCliM NSWRFS. (2006). Bushfire Bulletin (vol28 No.01). Retrieved from NSW Rural Fire Service: http://www.rfs.nsw.gov.au/__data/assets/pdf_file/0009/4122/Bush-Fire-Bulletin-2006-Vol-28No-1.pdf Penrith City Council. (2015). Updated South Creek Flood Study. Sydney: Worley Parsons pty Ltd. Schuster, S. S., Blong, R. J., Leigh, R. J., & McAneney, J. K. (2005). Characteristics of the 14 April 1999 Sydney hailstorm based on. Natural Hazards and Earth System Science, 5, 613-20. van Dijk, A. I., Beck, H., Crosbie, R. S., de jeu, R. A., Liu, Y., Podger, G., & Timbal, B. V. (2013). The Millennium Drought in southeast Australia (2001–2009): Natural and human causes and implications for water resources, ecosystems, economy, and society. Water Resources Research, 1040-1057.

WaterNSW. (2017, 06 09). Water Supply Historical Timeline. Retrieved from WaterNSW: http://www.waternsw.com.au/supply/Greater-Sydney/heritage/timeline

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