Step 3: Adaptation Planning & Design Logan Airport
Terminal A Satellite Doors to Harborside Substation CAT. 3 HURRICANE (MHHW) FLOOD EL. = 20.75 CAT. 2 HURRICANE (HAT) EST. FLOOD EL. = 18.42 CAT. 2 HURRICANE (MHHW) FLOOD EL. = 16.42 FIRST FLOOR EL. = 16.25 - All elevations are in NGVD. - Location is outside FEMA (2009, 2013) 100-year flood zone.
A. Removable Flood Panels B. Perm. Flood Doors
Wood Island Design Flood Elevations CAT. 2 HURRICANE (MHHW) FLOOD EL. = 16.93 CAT. 2 HURRICANE (HAT) EST. FLOOD EL. = 18.93 ) CAT. 3 HURRICANE (MHHW) FLOOD EL. = 20.93 FEMA BFE (2013) FLOOD EL. = 10.81 GROUND EL. = 9.93 FIRST FLOOR EL. = 11.60 - All elevations are in NGVD. - Location is outside FEMA (2009) 100-year flood zone.
Sliding Watertight Door with Pneumatic Seal
Step 3: Adaptation Planning & Design South Boston Maritime
Fish Pier East Design Flood Elevations FEMA BFE (2013) FLOOD EL. = 13.81 CAT. 2 HURRICANE (HAT) EST. FLOOD EL. = 18.28 CAT. 3 HURRICANE (MHHW) FLOOD EL. = 20.46 FEMA BFE (2009) FLOOD EL. = 9.81 GROUND FLOOR EL. = 11.11 - All elevations are in NGVD.
Design Elevations for Logan Airport 20 18 16 14 12 10 (Feet NGVD29) Cat 3 MHHW 20.78 f Cat 2 HAT 18.79 ft Cat 2 MHHW + 1 freeboard 17.79 ft Cat 2 MHHW 16.79 ft FEMA VE 2009 13.81 ft FEMA AE 2013 12.81 ft FEMA AE 2009 10.81 ft Cat 3 MHW 20.34 ft ~20.3 ft (DFE New Construction) Cat 2 MHW 16.35 ft ~16.4 ft (DFE Existing) FEMA VE 2013 14.81 ft Cat 2 MTL 12.31 ft Cat 1 MHHW 11.58 ft
Decision Matrix Existing Critical Facilities Protect and harden to CAT II Hurricane at Mean High Water (MHW) tide Earthquake retrofits Wind retrofits Others New Critical Facilities Design above CAT III Hurricane at MHW Earthquake design Wind design criteria Others
Risk-Based Prioritization Probability of Flooding Determined based on Inundation Model results Flooded in more storm scenarios higher probability, higher priority Criticality Score X Occupancy Category Consequence of Flooding Based on role in disaster preparedness, response, recovery Higher consequence higher priority Based on ASCE/SEI 24-05 Standard for Flood Resistant Design and Construction Depth of Flooding Further distinguish among assets with same Probability and Consequence Higher depth higher priority
Probability of Flooding Probability Storm Scenarios in which Asset is Flooded Number of Assets Higher Probability Cat 1 MHHW Cat 2 MTL, and Cat 2 MHHW 12* Intermediate Probability Cat 2 MTL and Cat 2 MHHW 2 Lower Probability Cat 2 MHHW only 41 * Wood Island and Porter Street Substations were moved from Tier 3 to Tier 1 due to strategic function and extremely high depth of flooding predicted under Category 2 MHHW scenario. Hydraulic study recommended to determine flood risk in lower storm/tide scenarios combined with high rainfall.
Consequence: Criticality Score Description Assets required for bare-bones functionality for disaster preparedness, response, and recovery Criticality Score 3 Assets required for disaster response in the immediate aftermath of a flood event 2 Assets required for facility to recover to acceptable level of service 1
Consequence: Occupancy Category Nature of Occupancy Buildings and structures designated as essential facilities including: Fire, rescue, ambulance, police stations, emergency vehicle garages Hurricane emergency shelters Emergency operation and communication centers Power generating stations/utilities facilities required during emergency Ancillary structures required for operation of Category 4 structures (communication towers, fuel storage tanks, electrical substations, fire water storage tanks or other fire suppression systems, water storage tanks) Aviation control towers and emergency aircraft hangers Water storage facilities/pump structures required to maintain water pressure for fire suppression Buildings having critical national defense functions Facilities handling and storing hazardous fuels Buildings and structures that represent a substantial hazard to human life in the event of failure, including: Buildings where more than 300 people congregate in one area Power generating station/public utility facilities not included in Category 4 Buildings not in Category 4 that handle hazardous materials, fuels, etc. All buildings and other structures except those listed in Categories 1, 3 and 4 Certain temporary facilities Minor storage facilities Category 4 3 2 1
Next Steps Design Consultant for Critical MPA Assets Resiliency Analyze existing flood proofing concepts and create design/specs for bid documents to implement temporary and permanent measures Develop an Operational Flood Plan and personnel training modules Tier 1 Assets implemented in first several years: $5 M Tier 2 and 3 re-analyzed with updated modeling, in future OPERATIONAL PLAN TEMPORARY FLOOD BARRIERS
Common Resiliency Recommendations Temporary Flood Walls
Common Recommendations Pedestrian Doors
Common Recommendations Overhead Doors
Common Recommendations Hydrostatic Relief Valve for Slabs
Common Recommendations Sump Pump System to Remove Water
Common Recommendations Shut-Off Valve for Sewer and Drainage Prevent backflow into flood-protected areas
Common Recommendations Seal Electrical Conduits Entering Building
Expansion Solutions
West Garage Expansion
West Garage Expansion
Continued collaboration Enhance Operational Resiliency Update the Continuity of Operations Plan Engage tenants Improve airside materials storage practices Collaborate with Other Agencies Demonstrate leadership through collaborating with, supporting, and learning from other complementary transportation entities Create a Resiliency Task Force Participate in external committees efforts at federal, state, and local level Sponsor Research/Share Lessons Learned
Measures of Resiliency Success Keeping facilities operational despite short-term events Rapid recovery after unplanned events Flexibility to redistribute some key activities to alternate locations/facilities Collaborative responses during and after events Protected critical infrastructure and facilities within balanced composite costs and risks program