Past, present and future flooding in New Zealand: trends and

responses

Professor Iain White

iainw@waikato.ac.nz

Introduction

1. Context: – Part academic, part research, part practical

– Its related to concepts central to your industry – risk, uncertainty, vulnerability and resilience

2. Trends: – Driving Trends - global, trends local (urbanisation, storms)

– Risk Trends - Evolving types of flooding and sources of data

– Impact Trends - more cascading effects and hidden risks – business interruption, critical infrastructure/ road/rail, water etc

3. Response: – Approach: how useful is the past in predicting the future? (historical data and

certainty)

– Insurance: In an uncertain future where data is less sure how do you better manage risk? – Be proactive not reactive, combine multiple data (social/climate), avoid maladaptation & promote flood resilience

2

O'Hare, P., White, I. & Connelly, A. (2015) 'Insurance as Maladaptation: Resilience and the 'business as usual' paradox', Environment and Planning C

1. CONTEXT: Research from 3 different fields: data, insurance and resilience

1. Concepts: ‘Risk’, ‘Vulnerability’, ‘Resilience’: how are they understood, by whom, and with what results?

2. Certainty: how sure are we? How is this communicated? How has our knowledge changed over time?

3. Managerial Approach: we’ve never known as much about flooding (or other issues) as we do right now, and yet the problems seem increasingly severe – why?

• Partly about how science and society addresses the problems; • Adaptation: both to a lack of data and vulnerable buildings/people

“It ain’t what you don’t know that gets you into trouble. It’s what you know for sure that just ain’t so.” Mark Twain

Wider Points…

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But need to problematise data… - Theory of time-space compression (Harvey 1990) - Defining a ‘natural disaster’?

10 or more people killed; 100 or more people affected; Declaration of a state of emergency; Call for international assistance

- Uncertain causality? Part forced, part natural, part socio-economic

2. TRENDS: Global trends for ‘disasters’

-Warnings, emergency response, technology, etc -Transfer of costs from death to social/economic

Global trends for impacts

Global and National Sea Level Change

• Is the global trend line still linear? Spikes?

• NZ tide records kept at the three main ports: Auckland, Wellington and Christchurch.

• These show an average rise in relative mean sea level of 1.6 mm per year (0.16 metres per century) over the 20th C

7

Annual mean relative sea-level data [black line] from the Port of Auckland, Waitemata Harbour, and the sea-level trend line [straight blue line] (1899–2007).

Coastal Flooding

- Likely that climate change will bring increased storminess. - Likely that tropical cyclones will be more intense bringing heavy rainfall, damaging winds, waves and storm surge to New Zealand. - More coastal flooding from increased frequency and magnitude of wind and storm surge - The sources of risk are waves, tides and driving winds

9

Precipitation: The new ‘normal’…

• Changes in distribution nationally: more rainfall in the west of both the North and the South Island and drier conditions in the east and north

• Changes within regions – more dry days but higher frequency of extreme daily rainfalls.

• Increased frequency of high temperatures (more drought)

• But how does this map onto population expansion?

(Ministry for Environment 2008)

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Trends: Social Drivers

• NZ's pop (4.4m in 2012) will increase to 5.4m in 2036 and 6.0 m in 2061 (Statistics NZ 2012)

• No. of households is projected to reach 2.09m by 2031, an increase of 536,000 from 1.55m in 2006

• More people = More risk (more exposure + more runoff + more demands on infrastructure) • Densification: increased runoff going into static infrastructure – infrastructure is designed to manage 2yr to 10 year event, but asset life maps poorly onto plan life – eg policy on increased density

• Increasing Cascading Impacts: infrastructure should be expected to fail more without investment

Uncertainty: Auckland Data and Trends

• About 20% of Auckland Region’s 500,000 buildings are at risk from flooding, 60% floodplain, but high % overland flow

• We have 2x the rainfall data/gauges from 20 yrs ago – so predictions of what is an extreme event are regularly reassessed - Eg a 1 in 100 year event could be changed to a 1 in 50 event afterwards

• 1 in 100 yr event relates to a ‘geographically distinct area’ – so if you have 300 areas, 3 may suffer per year. There are many of these areas in Auckland so you may expect a 1 in 100 event, somewhere in the city, every few years

• Lack of data on frequencies, eg 1 in 10, 20, 50 yr event etc – these are non-linear so a 1 in 100 isn’t the same as 100x a 1 in 1

• Infrastructure caters for between 2 to 10 yr event. But plan changes (e.g density) and gradual urbanisation reduces this – Life cycle of an asset is much greater than life cycle of a plan

• Climate change - a 2C temp increase may increase peak rainfall by 20%. Makes a 50 yr event into a 10 yr event – 5x more likely

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Approach: The ‘Growing’ Problem

• Historic use of probability/statistics, engineering solutions and ‘hard’ defences

• Supported by: tech developments in construction and engineering; scientific advances in probability and modelling; dedicated agencies with expert knowledge; huge financial investment (all elements of risk governance)

Given advances you would expect that we would manage flooding well, be increasingly certain & experience less events over time...but static/dynamic

Year

Estimated properties at risk (23m total in 2011)

Total

Rivers & Sea Surface Water Groundwater

2001

2004

2009

(White 2013)

Certainty: properties in England at risk of flooding over time

1998

2000

1947 1953

Flood Events

Year

Estimated properties at risk (23m total in 2011)

Total

Rivers & Sea Surface Water Groundwater

2001 1,724,225 0 0 1,724,225

2004

2009

(White 2013)

Certainty: properties in England at risk of flooding over time

1998

2000

1947 1953

Flood Events

2002

2004

Year

Estimated properties at risk (23m total in 2011)

Total

Rivers & Sea Surface Water Groundwater

2001 1,724,225 0 0 1,724,225

2004 1,740,000 80,000 1,700,000 3,420,000

2009

(White 2013)

Certainty: properties in England at risk of flooding over time

1998

2000

1947 1953

2002

Flood Events

2004

2007

2009

2005

2008

Year

Estimated properties at risk (23m total in 2011)

Total

Rivers & Sea Surface Water Groundwater

2001 1,724,225 0 0 1,724,225

2004 1,740,000 80,000 1,700,000 3,420,000

2009 2,400,000 3,800,000 1,700,000 6,800,000

(White 2013)

Certainty: properties in England at risk of flooding over time

1998

2000

1947 1953

2002

2007

Flood Events

2012/13/14

2004

2009

2005

2008

1. Risk: Technological focus on prediction, defence & ‘taming’ nature

- Question principle of stationarity: precipitation varies but over longer time series it is assumed to be stationary - eg 1 in 1000 yr event (Prague 1997, 2002), South Carolina has just received the 6TH 1 in a 1000 rainfall event since 2010…

2. Certainty: More data = more evidence = less confidence?

- Can we delineate between ‘safe’ and unsafe’ by a line on a map or % figure?

- How long is it accurate for?

- Need to be critical of simplistic spatial interpretations of complex phenomena

3. Approach: changed as data was ‘ground truthed’ after the event

-Resulted in a change in approach: from the disciplines involved, or whose knowledge counts, to funding regimes and the nature of research.

- Appreciation of the complexity of vulnerability for people and places

3. Response: Risk, Certainty and Approach

• Infrastructure at flood risk in England

• 2,358 schools

• 2,363 doctors surgeries

• 4,000km (10%) of roads

• 2,500km (21%) of railway;

• 55% of water treatment works and pumping stations

• 14% of all electricity infrastructure.

• Therefore can be at risk from the effects of flooding, even if not exposed

Response: Understand Cascading Vulnerability

Understand Contextual Vulnerability

• Related to societal drivers and a feeling of powerlessness – how will this change? Is society become more unequal?

• E.g. Consider demographics, financial resources, education, inequalities, etc

• Also support systems, emergency response, insurance availability, access to resources, engagement and decision making.

• Focus on the ability to cope...why does this differ?

• Autonomous adaptation? Lessons from elsewhere?

Conceptual Response: shift to Resilience

1. Risk as a ‘calculative rationality’: (Risk=Probability x Consequence)

2. Alternatively Beck (1992) argued that risk is incalculable as it is based on ways of knowing: ‘The dominant...approach is more than a method; it is a misbegotten culture which inadvertently but actively conceals that ignorance’ (Wynne 2009: 308)

• ‘As we know, there are known knowns; there are things we know we know. We also know there are known unknowns; that is to say we know there are some things we do not know. But there are also unknown unknowns - the ones we don't know we don't know.’ Donald Rumsfeld, former US Secretary of Defense, 12/02/2002.

Argues knowledge is incomplete, but we still need to make decisions. Calculative rationalities deal with known knowns, but all risks cannot be measured. How do we manage uncertainty? And who does it?

State Response: the flood resilient citizen?

• Shift from flood defence to flood risk management changes responsibility

– Increasing role for private sector and State not expected to protect

• ‘Responsibilisation’ agenda

– Political project supported by technological innovation & capacity building

– But reluctance to use technologies

• Insurance as a means to ‘purchase’ resilience

– frames hazard response, promotes adaptation (behaviour and technology)

• Reduces vulnerability, provides certainty, & rebuilds lives, livelihoods and properties

a transition from self protection to engineered defence to natural management

Change in Approach

Change in Approach

Building hard defences by rivers and the sea

Cost intensive solution

Unable to tackle all sources of risk

“Escalator effect” on risk

No real preventive planning

Flood Defence Integrated Flood Risk Management – public, private and individuals

Flood Defence

Insurance

Citizens

Resilience strategies/ technology

Spatial Planning

8 Case studies across Europe

Manchester, UK Surface water flooding, Individualistic insurance

Valencia City on an estuary with mountainous areas. Solidaristic Insurance

Paris Fluvial and Pluvial Floods; Solidaristic Insurance

Athens Flash Flooding Individualistic insurance

Cyprus Flash flooding, Individualistic insurance

Dresden Riverine flooding Individualistic insurance

Hamburg Estuarine flooding Individualistic insurance

Rotterdam Combination of pluvial, fluvial and estuarine flooding. Strong tradition of building flood defences Solidaristic insurance

Smart Resilience Technology Systems and Tools (SMARTeST) 4.8m Euros ($8m) Examining the road to market for flood resilient technology (inc insurance)

Images courtesy of the Building Research Establishment

Flood door and guard

Non-return valves Automatic dam

Testing the technology

Buildings and Temporary/community scale

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When appropriate?

1. Retrofit – only 1-3% pa is new

2. To manage surface water flooding

3. Where data is uncertain

4. For smaller settlements that may not justify significant expenditure

5. For valuable buildings or critical infrastructure

• Sector: emergent sector of small businesses – standards and quality?

• Public: rather be protected by defences. Lack confidence in technology and manufacturers and unsure of process

• Decision-makers: lack knowledge to recommend – hard to compare products, companies and results.

• Insurers: need info on performance, standards and how to price it.

• ‘Trust’ is a key theme; from the market in general to performance to installation to its effect on your insurance premium

• There is consensus that a ‘Best Practice’ document could mitigate many barriers. But how can it be independent yet have ‘buy in’?

Barriers to Resilient Buildings

www.smartfloodprotection.com

Town & Country Planning Association, Feb 2015 http://www.tcpa.org.uk/data/files/Journal_Blurb__Sample_Articles/Feb_2015_Sample.pdf

STEP 1: UNDERSTANDING THE RISK

• A full flood risk mitigation survey should be performed by an independent surveyor who will recommend the FRe technologies that may be employed .

STEP 2: PLANNING A SCHEME – FIRST CONSIDERATIONS

• The pros and cons of various products should be weighed up including ease-of-use, performance specification, cost, and so on.

STEP 3: SURVEY

• Manufacturer(s) will need access to the site to fully measure it in order to design the products and to undertake an assessment of its current state .

STEP 4: DESIGN AND SPECIFICATION

Manufacturer(s) will design the FRe technologies with the end-user in mind. Materials will be cleared with the end-user. The FRe technologies will be clearly specified with an indication of when they will not work.

STEP 5: INSTALLATION

Manufacturer(s) will provide installers with a clear set of instructions. The installer will need access to the site. All work shall be signed off by the initial surveyor, the site/property owner and the manufacturer.

STEP 6: OPERATION AND MAINTENANCE

Manufacturer(s) and/ or installers will train the end-user on how to operate equipment in the event of a flood. A manual with clear maintenance and operation instructions will be presented to the end user.

Insurance and adaptation to future risk

• Risk Transfer: mitigate flood impacts by insurance – but inhibits change – Insurers organise recovery - Property owners cede autonomy

– Moral hazard: those subjected to hazard/ those bearing costs

• Risk pooling & policy bundling: spread exposure – but inhibits change – Individualist/risk-sensitive insurance: less fair, but enables adaptation

– Solidaristic insurance: socially beneficial, but can inhibit adaptation

• Prohibition of betterment: rapid ‘bounce back’ to pre-shock status - but not better adapted to cope with future risk (no property improvement) – Aftermath a prime ‘window of opportunity’ to adapt to future risk,

"After the first flood my insurer was great! They sorted everything out – a new home; a new telly! But that didn’t stop flooding a second or a third time”

(property owner)

Insurance as Maladaptive

• Insurance is seen as key to resilience, but...

• Insurance privileges view of resilience as return to normality not adaptation to less risk – Risk transfer & moral

hazard

– Risk pooling & bundling

– Indemnity principle & anti-betterment

• Bouncing back rather than bouncing forward….

Conclusion: science, risk & adaptation

• The perception of a hazard changed: Flooding moved from a technical to a socio-technical assemblage – which is less spatially and managerially convenient

• Some disciplines privilege old ways of knowing: ‘Regardless of developments in science, evidence or planning, risk management is essentially the authoritative mask behind which risk taking hides’.

• Information has authority: uncertain data can look certain when moving from science to the real world

• The past may be less useful at predicting the future

• May need a resilience approach to manage more uncertain risks – defences behind the defences…

• ‘Business as usual’: A good selling point, but flexible enough to enable change to cope with uncertainty?

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Thank you – any questions?

Professor Iain White – University of Waikato – iainw@waikato.ac.nz • Connelly, A., Gabalda, V., Garvin, S., Hunter, K., Kelly, D., Lawson, N., O' Hare, P. and White, I.

(2015) Testing Innovative Technologies to Manage Flood Risk, Proceedings of the ICE - Water management, 168 (2), February: 66-73.

• O'Hare, P., White, I. and Connelly, A. (2015) Insurance as maladaptation: Resilience and the 'business as usual' paradox, Environment and Planning C, 1-19. DOI: 10.1177/0263774X15602022.

• White, I. (2013) 'The more we know, the more we don't know: Reflections on a decade of planning, flood risk management and false precision’, Planning Theory and Practice 14 (1): 106-114