Storm Surge Mitigation: Status and Questions. Scott A. Jones Director of Advocacy Galveston Bay Foundation

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1 Storm Surge Mitigation: Status and Questions Scott A. Jones Director of Advocacy Galveston Bay Foundation

2 Galveston Bay Foundation Mission: To preserve, protect, and enhance the natural resources of Galveston Bay and its tributaries for present users and for posterity. Four target areas: Advocacy Education Conservation Research

3 Hurricane Ike 9/13/08 Galvanized local efforts to address storm surges. Revealed vulnerabilities of immediate coastal and bay communities and HSC industries. NOAA But this is nothing new

4 History of Storms and Responses 1900 Storm leads to Galveston Seawall - authorized by Texas legislature in First segment completed in Last segment extended seawall to 99 th Street in Galveston and Texas History Center Rosenberg Library Halff Associates Texas City levee authorized by USACE in 1958.

5 Upper Texas Coast Sea Level Rise (SLR) Background or natural sea level rise. In geological time scale, we are coming out of last ice age. Factor in movement of landmass and you have relative seal level rise (RSLR). NASA JSC

6 Subsidence =Accelerated RSLR Data source: HGCSD 2008; TWDB 2008

7 Shoreline Changes Beach/Dune Profile Translation Height Above NAVD88 (m) vertical exaggeration = 10:1 High Geohazard Potential/ Future Critical Environment Imminent Geohazard Potential/ Present Critical Environment 2002 profile 2062 estimated profile Distance from Monument (m) Gibeaut, UT BEG, 2007

8 Climate Change Accelerated sea level rise with global warming. Source: Hayhoe & Farley, A Climate for Change (2009)

9 So here we are Retreating beaches and eroding shorelines... People and infrastructure are in harm s way Galveston Bay natural resources in peril???

10 What are we trying to protect? What do we need to protect?

11 What are we trying to protect? What do we need to protect?

12 Responses to Ike - Ike Dike Concept Dr. Bill Merrill, TAMUG, Dike from High Island to Freeport. No formal plans for GBF to comment upon yet.

13 Ike Dike Concept Floodgate

14 Ike Dike - Questions Costs to build? Costs to acquire land? Costs to maintain? Exactly where? Old Hwy 87? FM 3005? Seawall? Blue Water Highway? Dune line?

15 Ike Dike - Questions Sufficient sediment budget? Will Ike Dike become a new seawall along this whole reach? Is that acceptable? Will the beaches and dunes be lost to sea level rise and erosion if shoreline not hardened?

16 Ike Dike Questions Direct impacts to habitat. Indirect impacts to habitat. Changes to bay circulation. Green light to runaway development?

17 Responses to Ike SSPEED Center Rice Univ. Severe Storm Prediction, Education, and Evacuation from Disasters

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20 SSPEED Center Ike Dike and Alternatives A number of structural and non-structural alternatives exist that offer varying levels of protection from hurricane surge flooding, rainfall and wind. A thorough examination and comparison of the economic costs, environmental impacts, social hazards and overall reliability and effectiveness of these alternatives should be completed before any final selections. -Executive Summary, Learning the Lessons of Hurricane Ike, SSPEED Center, May 2010

21 SSPEED Center Ike Dike and Alternatives In studies conducted in Florida and Texas, non-structural alternatives have been found to be consistently more effective in reducing flood damage than structural control measures. As such, they are being evaluated as an alternative to traditional structural options. -Executive Summary, Learning the Lessons of Hurricane Ike, SSPEED Center, May 2010

22 SSPEED Center Structural and Non-Structural Alternatives Ike Dike Zone Specific Levee Solution Land-Use Controls Natural Surge Protection - Land Acquisition and Conservation Easements Buffer Zones Building Elevations Building Codes Evacuation Planning and Improvement

23 SSPEED Center Houston Ship Channel Gate

24 SSPEED Center Houston Ship Channel Gate

25 SSPEED Center Lone Star National Recreation Area

26 SSPEED Center Alternatives Questions Will our beaches, dunes and the bay margines be lost to sea level rise and erosion if Gulf shoreline is not hardened? Will oyster reefs be lost in the next Ike? Are there other living resources that really need protecting? Will people outside of zone-specific levee system be left in harm s way? Is that acceptable? Will zonespecific levee system amplify impacts to unprotected areas?

27 SSPEED Center Alternatives Questions Can people be better evacuated out of harm s way? Can we implement strategies to keep people out of harm s way from now going forward into the future? Can development in areas on the barrier islands be halted? Can land for Lone Star NRA be acquired/protected?

28 Join the GBF team as an individual or corporate member Volunteer with GBF!

29 Extra slides

30 Subsidence Burnet Bay

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34 Gulf Coast Community Protection & Recovery District Harris Galveston Brazoria Chambers Orange Jefferson Guidry News Service, 2010

35 In the meantime, let s keep doing some things Habitat restoration Habitat conservation: preserves and easements.

36 Natural surge mitigation