from drought to floodpresentation overview from drought to flood • my background • australia’s...
TRANSCRIPT
From Drought to Flood
Presented by:
Chris Huxley
September 2015
Presentation OverviewFrom Drought to Flood
• My background• Australia’s millennium drought• Drought breaking floods• Australia vs USA flood
planning environment• An assessment of flood
awareness in Sacramento• Where to from here?
www.bbc.com
https://commons.wikimedia.org
My BackgroundChris Huxley
• Australian, Hydraulic Engineer• Consulting and flood modeling
software background• 15 years industry experience• 30+ Flood Risk Management Studies
in NSW and QLD• Post flood insurance assessments• Relocated to California, June 2014• Disclaimer: This presentation is based
on my experience and observations
The Millennium DroughtThe Numbers
• 1997-2010 (13 years)• Worst on record (230 years)
Rainfall Deciles1 November 2001 to October 2009
Murray - Darling Basin: Australia’s Food Bowl
The Millennium DroughtThe Numbers
• 1997-2010 (13 years)• Worst on record (230 years)
• Five state coverage (1/3 USA)
The Millennium DroughtThe Numbers
• Affected 7 of the 8 state/territory capital cities (<25% water supply capacity)
• 85% of the country’s population directly affected
• Some inland towns reliant on land transported water resupply
• Federal Govt. announcement(19 April 2007) “unless there is substantial rain in the next six weeks no water will be allocated to irrigators in the Murray-Darling basin for the coming year” Rainfall Deciles
1 November 2001 to October 2009
Population Density
The Drought Breaking FloodThe Record Breaking Wet
Major flooding in Queensland, New South Wales and VictoriaQLD 2011/2012 Flood• 78% of QLD disaster
declared • 32 deaths• 2.5 million people
affected (10% of the Australian population)
• Over $10 - $30 billion dollar cost (Aust $)
Rainfall Deciles1 November 2010 to January 2011
Major
Moderate
Minor
Lockyer Creek at Helidon: Highest Annual Flood Peaks
The Drought Breaking FloodThe Record Breaking Wet
The Drought Breaking FloodThe Response – Queensland Floods Commission of Enquiry
QFCoI: Legal enquiry into• Preparation and planning for floods
by governments, agencies and the community
• Adequacy of response to the floods • Management of essential services • Adequacy of forecasts and early
warning systems• Insurers’ performance • Land use planning 68 days and 6133 pages of evidence
http://www.floodcommission.qld.gov.au/
The Drought Breaking FloodKey Lessons Learnt
• Prior assessment of the flood behavior for a range of event magnitudes is essential for all aspects of planning.
• Structural flood mitigation measures are NOT failsafe!!
• Land use planning is the most effective way to build future community resilience.
• Emergency response planning is required to manage residual risk
• Public education is critical for effective emergency response
news.com.au
USA vs AustraliaFundamental Policy Differences
USA AustraliaGreater pool of available funding (NFIP and Govt funding)
Smaller pool of available funding NDRP 2015/16 = $120 million
Focus on structural mitigation Focus on less costly options (Emergency response planning)
Defined Flood Event (DFE) floodplain planning mentality
Transitioning to risk based landuseplanning
“While a DFE (the 1%AEP) may be a useful general approach, it is important that policy makers should review this risk level and adopt a suitable flood probability based on an acceptable risk for different locations, land use and infrastructure in the floodplain” (Queensland Reconstruction Authority)
USA Structural Mitigation?
What are potential issues with an emphasis on structural mitigation?• Community risk perception can decrease • Can hinder community response during an event• Actual risk can still be significant due to increased consequences
Change in risk register due to levee construction.
Additional mitigation is required to further reduce remaining residual risk
Community ResearchSacramento / Natomas Resident Survey
Sacramento / Natomas Resident Survey• 2000 letter mail drop• Only 110 respondents
Question Yes No Maybe
Do you know if your property is located within a flood zone? 83 17 N/A
If yes, is your property in a flood risk zone? 54 46 N/A
Do you know where local real-time flood information can be obtained ? 30 70 N/A
Do you know which river gage is located closest to your property? 25 75 N/A
Community ResearchSacramento / Natomas Resident Survey
Community ResearchSacramento / Natomas Resident Survey
Question Yes No Maybe
If a flood warning were issued, would you expect your property to be flooded? 10 39 51
If a flood evacuation were issued, would you evacuate? 94 6 N/A
Do you know where your local flood evacuation center is located? 5 95 N/A
Do you know the preferred evacuation route to the flood evacuation center? 5 95 N/A
ConclusionWhat now?
Land use planning is fundamental to building future community resilience
http://qldreconstruction.org.au/
ConclusionWhat now?
Land use planning is fundamental to building future community resilience
ConclusionWhat now?
Land use planning is fundamental to building future community resilience
It incorporates all aspects of floodplain management
http://qldreconstruction.org.au/
ConclusionFinal Message
Major disasters often prompt a review of public policies, resulting in change for the better (hopefully)
We know the risks associated with flooding!!
It’s our collective responsibility to keep flood issues in the public and political consciousness during dry periods.
http://qldreconstruction.org.au/
Thankyou
Chris HuxleyWood Rodgers, Inc.3301 C Street, Bldg. 100-BSacramento, CA 95816
916.341.7760 Tel916.341.7718 Direct916.533.6071 Mobile
[email protected]@woodrodgers.com