Overview of USACE Civil Works Climate Preparedness and Resilience and Challenges with Recurring Flood Damage in Virginia

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1 Overview of USACE Civil Works Climate Preparedness and Resilience and Challenges with Recurring Flood Damage in Virginia Michelle Hamor Chief, Flood Plain Management Services Section USACE, Norfolk District Virginia Floodplain Management Association October 29, 2015

2 Bottom Line Up Front USACE has a long history in understanding climate impacts to mission and operations Lessons learned especially from floods help guide work to increase future resilience USACE integrates and translates science for decision-makers so they can focus on analysis rather than data management 2

3 Ice Cores and Water: Fundamental Climate Information Between 1950 s and 1980 s, two USACE entities were involved in drilling for polar ice cores in Greenland Snow, Ice and Permafrost Research Establishment (SIPRE) Cold Regions Research and Engineering Laboratory (CRREL) Prompted by droughts in late 1970 s, the USACE Institute for Water Resources (IWR) undertook a series of studies 1987 sponsored National Research Council report "Responding to Changes in Sea Level: Engineering Implications." st National Conference on Climate Change and Water Resources Management 1992 began Economic Impacts of Climate Change Program Provided climate analysis for Upper Mississippi, Lower Mississippi and Illinois Rivers Flow Frequency Study 3

4 Lessons Learned From Katrina: Incorporate New and Changing Information Systems approach should include dynamic conditions such as subsidence, global sea level rise, and other climate change Life-cycle performance should be examined, including resilience, redundancy, and unanticipated failure modes Social impacts often fall disproportionately on the most vulnerable 4

5 Lessons Learned From Nashville (2010): Existing Flood Storage May Not Map To Future Floods Four primary factors unseasonably strong late-spring storm system stationary upper-air pattern persistent tropical moisture feed timing of impulses moving through the jet stream Controlled basins have the primary purpose of flood storage: Wolf Creek Dam, Dale Hollow Dam, Center Hill Dam, and J. Percy Priest Dam Uncontrolled basins have the primary purpose of maintaining navigation depths: Cordell Hull L&D, Old Hickory L&D, and Cheatham L&D 5

6 Lesson Learned from the Floods of 2011: Post-1927 Plan of Room for River = Resilient Design Water resources engineers are accustomed to making decisions under deep uncertainty 6

7 Lesson Learned from Sandy (2012): Tough Choices Ahead 7

8 Lesson Learned from Sandy: Use the Full Portfolio of Measures Over Continuum of Events Hypothetical Northeastern Coastal Community Quantification of performance of natural and nature-based coastal risk reduction measures is a critical knowledge gap Lopez, J.A. (2009) JCR The Multiple Lines of Defense Strategy to Sustain Coastal Louisiana 8 8

9 USACE 2014 Climate Change Adaptation Plan Focus on specific areas Infrastructure Resilience Vulnerability Assessments Risk-Informed Decision-Making for Climate Change Nonstationarity Portfolio of Approaches Metrics and Endpoints Engage in meaningful external collaboration Improve USACE knowledge for water resources management and infrastructure resilience Develop policy and guidance for Infrastructure resilience 9 9

10 Nonstationarity Hydrology Stationarity allows us to assume that the future will resemble the past. Engineers already recognize that nonstationarity can occur, for example when a dam is built and prevents large flows, or when land use or land cover changes impact the distribution, mean, or variance of flood flows. 10

11 USACE Climate Preparedness and Resilience: Translating Science into Actionable Information 1. Start where strongest evidence maps to missions and operations 2. Consider interrelationships and cascading impacts 3. Move to other impacts as science evolves POST-FIRE FLOOD/DEBRIS WILDFIRE TORNADOES HURRICANES SEVERE DROUGHTS EXTREME PRECIPITATION EVENTS COASTAL FLOODING HEAT WAVES 11

12 USACE Resilience Definition "resilience means the ability to anticipate, prepare for, and adapt to changing conditions and withstand, respond to, and recover rapidly from disruptions. Presidential Executive Order 13653, Preparing the U.S. for Impacts of Climate Change (NOV 2013) Adapt Prepare Recover Absorb 12

13 Tools Supporting Climate Preparedness and Resilience Policy and Guidance Existing: Tools should shift emphasis from data management to analyzing potential risks and adaptation Sea level calculator Three tools in prep based on archive of climate and hydrology data: ECB in external review, release fall 2015 ETL , nonstationarity, release end of CY 2015 Flow frequency tool, FY

14 USACE Sea Level Adaptation Policy and Guidance Sea Level Change: 1986 guidance letter consider changing sea levels 2000, ER sensitivity to historic and NRC high rate sea level change 2013, ER (supersedes 2009 and 2011 s EC and ) use 3 scenarios 2014 ETL , adaptation to changing sea levels, uses tiered approach with level of effort commensurate with scale of decision and consequences Total Water Levels: In progress: ETL on Procedures to Evaluate the Magnitudes and Effects of Total Water Levels at USACE Projects, draft expected

15 Tools: Coastal Climate Change Sea level change calculator Supports repeatable results Relies on NOAA tide gauge data Includes some long-term non-noaa tide gauges in the Louisiana Gulf Coast area Publicly available Interagency Sandy Sea Level Rise tool Supports comparisons to NOAA 2012 scenarios New York City Panel on Climate Change NRC 2012 Pacific Coast CESL tool Progressively more detailed screeninglevel assessments of coastal vulnerability Relies on NOAA, USGS, other data and products 15

16 USACE Climate Hydrology Policy and Guidance ECB : Guidance for Incorporating Climate Change Impacts to Inland Hydrology in Civil Works Studies, Designs, and Projects To be updated ahead of May 2016 Not quantitative yet but will be expanded somewhat ETL : Appropriate Application of Paleoflood Information for Hydrology and Hydraulics Decisions 17

17 Upcoming Climate Hydrology Policy and Guidance ETL : Guidance for Detection of Nonstationarities in Annual Maximum Discharges In external peer review now (IEPR) Accompanying web tool in external review Expected release date end of CY2015 Draft ETL on detection of nonstationarity for minimum flow, tide gauge records and potentially other variables CY16 19

18 Status Check Do we have all the answers? No Are we getting there? Yes, we are moving toward more quantitative guidance that is supported by actionable science developed in collaboration with our partners and stakeholders, AND will not require major adjustments 23

19 Locally USACE Engaged on local and regional teams Chesapeake Bay Program Climate Steering Committee Virginia Silver Jackets Team Hampton Roads Intergovernmental Pilot Project Hampton Roads Sea Level Rise Advisory Committee Evaluating vulnerabilities for existing USACE projects Vulnerability assessments through FPMS and PAS programs Silver Jacket Interagency Nonstructural Projects Nonstructural and structural solutions through Continuing Authority Programs General Investigations 24

20 Recurrent Flooding Challenges in Virginia Challenge #1 Cumulatively, recurrent flooding damage can equal a disaster. 25

21 Recurrent Flooding Challenges in Virginia Challenge #2 Solutions need a systems approach. 26

22 Recurrent Flooding Challenges in Virginia Challenge #3 Solutions need to be redundant. Flooding will occur where it is not mapped. 27

23 Recurrent Flooding Challenges in Virginia Challenge #4 Show me the money. 28

24 Recurrent Flooding Challenges in Virginia Challenge #5 Make the tough decisions. 29

25 Recurrent Flooding Challenges in Virginia Challenge #4 If you build it, they will come. 30

26 Recurrent Flooding Challenges in Virginia Other Challenges 31