GIS and Database Tools for BART Seismic Upgrade. John Eidinger G&E Engineering Systems Inc.

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1 GIS and Database Tools for BART Seismic Upgrade John Eidinger G&E Engineering Systems Inc.

2 Agenda BART wants to do a comprehensive seismic evaluation and upgrade of its train system BART needs to raise money to do the work How SERA risk analyses helped define Pre- Earthquake retrofit strategies; Benefit-Cost tests How real-time SERA-SHAKEMAP analyses helps define Post-Earthquake emergency response strategies How SERA is used to track actual seismic upgrades

3 What is SERA? System Earthquake Risk Assessment Customized GIS-based program for risk analyses of water, power and transit systems Similar to HAZUS, but greatly refined for utility / network systems Includes interfaces to Shakemap and RDMS tools

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5 BART Concerns Upgrading everything to Full Operability is going to cost too much (> $3 billion) Could system-risk concepts show if there is an intermediate level of upgrade which gets good enough performance at an economically-sound cost?

6 BART Seismic Retrofit Question: What can (or should) be done to make BART perform better after earthquakes? Option 1: Upgrade every component in BART to a Life Safety standard; or Option 2: Upgrade every component in BART to a Full Operability standard Intermediate Options: Upgrade every component in BART to a Life Safety standard plus some selected components to a Full Operability standard

7 Six Retrofit Alternatives Retrofit Alternative Description Total Cost ($1,000) 1. Life Safety Upgrade aerial guideways, selected (LS) passenger stations, selected buildings, the 594, Partial Operability 1 (PO-1) 3. Partial Operability 2 (PO-2) 4. Partial Operability 3 (PO-3) 5. Full Operability (FO) 6. Extended Operability (XO) Transbay Tube and select equipment All Life Safety retrofits, plus Full Operability retrofits from Rockridge Station to Colma, additional upgrade to the Lake Merritt Administration building All Partial Operability 1 retrofits, plus Full Operability retrofits from MacArthur Station through North Berkeley Station and from the Oakland Wye through Coliseum Station All Partial Operability 2 retrofits, plus Full Operability retrofits from Coliseum Station through South Hayward Station All Life Safety retrofits, plus additional upgrades to aerial guideways, additional upgrades to passenger stations, additional upgrade to the Lake Merritt Admin Bldg, additional upgrades to equipment important for operations, plus stabilization of the embankments near gravel pits in Fremont. All Full Operability retrofits, plus a 3 rd bore for the Berkeley Hills Tunnel at the Hayward fault crossing. 737, ,033 1,105,445 1,323,319 1,443,319

8 BART Inventory $10.85 Billion Replacement Value ($2002) 3089 Sites 15,103 Individual Buildings, Aerial Columns, Tunnel Segments, Track Segments, Pieces of Equipment (since updated to 30,000 individual components) Typical Spacing of Sites: 70 feet (aerial); 300 feet (at grade or tunnel) All geo-coded in SERA

9 Categor y BART Inventory Description 2002 Model 2006 Model AG Aerial Structure GR Girder TN Tunnel TR Track PS Passenger Station BL Building-Occupied BX Building-Not Occupied EM Embankments EQ Equipment 2,470 26,696 Total 15,670 39,896

10 Aerial Structures (1988 total) Type Column Footing Quantity I(a) Single On Grade 495 I(b) Single On Piles 885 I(c) Single On Piles 36 II Abutment On Piles 143 III Single On Piles 54 IV Single On Piles 88 V Multiple On Piles 38 VI Multiple On Piles 31 9 Single Extension Abutment Extension 43

11 Aerial Structures 9 10 I(a) IV VI V I(a) I(b) I(c) II III III IV II I(c) V VI 9 10 I(b)

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18 Seismic Hazards Select Scenario Earthquakes (4) Select Fault, Magnitude, Location Hayward M 7.0 San Andreas M 8.0 Calaveras M 6.8 Concord M 6.8 Loma Prieta 1989 (For Benchmark)

19 Seismic Hazards Evaluate for each scenario earthquake: Ground shaking (PGA, PGV, Spectra, duration) Surface faulting (location, amount in feet) Liquefaction (potential, settlement and lateral spread, in feet) Landslide (potential, downslope movement in feet) Run 100 simulations of each earthquake

20 Ground Shaking Hazard SERA Incorporate 5 attenuation models: Use average motion from 5 attenuation models Include fault directivity function Include fault normal / fault parallel function Include inter-event stress drops between simulations Include intra-event correlation of motion between sites

21 FRAGILITY 166 Sets of Structure Fragility Curves As many as 23 damage states in one set 10 sets for Aerial Columns 15 sets for Tunnels 43 sets for Passenger Stations 41 sets for other Occupied Buildings 7 sets for non-occupied Buildings 470 Sets of Equipment Fragility Curves

22 Functional Goals Passenger Trips at a percentage of preearthquake trips Consider station pairs (Rockridge-to- Concord vs. Embarcadero-to-Concord) Impact by time delays to customers

23 Ridership Matrix (Daily Average) C10 K10 K20 M10- C10- Origin Dest K30 M10 A10 A20-A30 A40-A70 A80-A90 C20-C80 L10-L30 M16-W20 R10-R30 R40-R60 M16 C20 Total C10 K10 K20 K30 M10 A A20-A A40-A A80-A C20-C L10-L M16-W R10-R R40-R M10-M16 C10-C20 Total

24 SERA Analysis Monte Carlo simulations Includes actual geotechnical models, inventory, fragilities, uncertainty, randomness Tabulate damage for each scenario earthquake, for median, lower bound, upper bound Tabulate for the system and for individual component. Maps

25 Summary ($ Millions) Long Term Repair Costs STATUS QUO Scenario Earthquake Expected Minimum Maximum 16 th Percentile 84 th Percentile Hayward San Andreas Calaveras Concord Loma Prieta Based on 100 Simulations for Each Scenario Earthquake

26 Summary ($ Millions) Long Term Repair Costs with LIFE SAFETY RETROFIT Scenario Earthquake Expected Minimum Maximum 16 th 84 th Percentile Avg Reduction Percentile Hayward % San Andreas % Calaveras % Concord % Based on 100 Simulations for Each Scenario Earthquake

27 Sites with major Life Safety Exposure Hayward M 7 San Andreas M 8 Calaveras M 6.8 Concord M 6.8 Status Quo Life Safety Pct Reduction 97% 97% 95% 87% Conclusion: LS Upgrades eliminate most, but not all major Life Safety risk

28 Performance of Alignment 4 Scenario Earthquakes Maps show functional stations of Stations, Elevated, Underground, At Grade alignment Black = No Go (structural damage, equipment damage) White = Go Slow (structural damage that can be repaired with temporary fixes) Gray = Ok (either no damage, or damage which has no functional impact) Large circle = station

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37 Performance of Buildings and Equipment 4 Scenario Earthquakes Performance code: Black = No Go (structural damage, equipment damage) White = Go Slow (structural damage that can be repaired with temporary fixes) Gray = Ok (either no damage, or damage which has no functional impact) Squares = Buildings Triangles = Substations, Gap Breaker Stations

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39 Benefit-Cost Analysis Consider 4 large impact earthquakes: Hayward M7, San Andreas M8, Calavaras M6.8 and Concord M6.8, and Consider 9 smaller impact earthquakes: Hayward M6.4, Hayward M6.0, San Andreas M7.0, San Andreas M6, Calavaras M6.4, Calavaras M6.0, Concord M6.4, Concord M6.0, Rodgers Creek M7.0. For each scenario, calculate damages and losses per event and then annualize them by multiplying by the annual probability of each event Do this for the status quo condition of BART and for each of six levels of seismic retrofit.

40 What are Benefits? Benefits are the expected reduction in damages, losses, and economic impacts from future damaging earthquakes Benefits are calculated as a net present value, reflecting: probabilities of future earthquakes a 5.5% discount rate for present value calculations, and a 50-year useful lifetime of retrofits

41 Perspectives For benefit-cost analysis, there are three possible perspectives: BART (damages, loss of revenue, other costs) BART riders - economic impact of loss of service SF Bay Area as a whole - economic impact of loss of service Broader perspectives count more benefits

42 Benefits: BART Perspective Avoided Repair Costs for future seismic damages Note: under current FEMA regulations, FEMA would likely cover 75% to 90% of eligible repair costs Avoided Revenue Loss from reduced service and loss of riders Avoided additional costs for bus bridges to bypass closed parts of BART system

43 Benefits: BART Rider Perspective Avoided extra transportation costs vehicle operating costs tolls parking fees Avoided loss of time (extra transportation time) valued using FEMA methodology average value of $32.20 per hour, which is the average level of wages and benefits for the SF Bay area assume that each displaced BART rider loses 30 minutes time per one way trip

44 Benefits: SF Bay Area Perspective Loss of BART service and corresponding increase in traffic volume will increase congestion throughout the SF Bay area and impact the entire area, not just displaced BART Riders The economic impacts of the lost time are likely to be at least as large as those for BART riders

45 BART Seismic Retrofits: Benefit-Cost Analysis Incremental Retrofit Cost ($million) Incremental Benefits ($million) Benefit Cost Ratio BART Condition Status Quo n/a n/a n/a Life Safety $595 $2, Partial Operability - 1 $142 $ Partial Operability - 2 $126 $ Partial Operability - 3 $242 $ Full Operabillity $218 $ Extended Operability $120 $

46 Target Performance Goals Goal Description As Is P-1 P-2 P-3 P-4 P-5 P-6 LS PO-1 PO-2 PO-3 FO XO Capital Cost ($ Billions) $ Benefit Cost Ratio (Upper Bound) n.a Benefit Cost Ratio (Lower Bound) n.a All occupied structures meet basic Life Safety goal of 1960's Yes Yes Yes Yes Yes Yes Yes 2 All occupied structures meet basic Life Safety goal of 2000's No Yes Yes Yes Yes Yes Yes 3 No major damage after MCE No No No No No No No 4 No major damage after MCE except for the Berkeley Hills Tunnel No No No No No Yes Yes 5 No minor damage after MCE No No No No No No No 6 100% recovery of service within 60 days after MCE No No No No No No Yes 7 100% recovery of service within 60 days after MCE with 1 bus bridge No No No No No Yes Yes 8 100% recovery of service within 60 days after MCE, some slow operations, with 1 bus bridge No Yes Yes Yes Yes Yes Yes 9 1 or more Maintenance Yards No Yes Yes Yes Yes Yes Yes 10 2 or more Maintenance Yards (1 for C-Line) No No No No Yes Yes Yes 11 90% recovery of service within 60 days after MCE No No No No No Yes Yes 12 80% recovery of service within 60 days after MCE No Yes Yes Yes Yes Yes Yes 13 70% recovery of service within 60 days after MCE No Yes Yes Yes Yes Yes Yes 14 50% recovery of service within 60 days after MCE Yes Yes Yes Yes Yes Yes Yes % recovery of service within 72 hours after M 6 No No No No No No Yes % (95%) recovery of service within 72 hours after M 6 with 1 bus bridge No Yes Yes Yes Yes Yes Yes % recovery of service within 72 hours after MCE outside BART service area No Yes Yes Yes Yes Yes Yes Goals Met

47 Life Safety Retrofits - Buildings 17 Buildings with Proposed Retrofits Total Retrofit Cost = $24.6 M + $2 M for non structural components Average Retrofit Cost = $15/sq ft Range of Retrofit cost = $6 to $299 / sq ft

48 Ranking of Building Retrofits Number Location Description Use Square Feet Replacement Value / Sq Ft Replacement Value ($K) Occupancy 1 Daly Colma(Daly City) Transportation Bldg Office 11,484 $ $3, Daly Daly City Shop Shop 22,950 $ $8, Daly Daly City S & I Bldg (Pre-maint. bldg) Service 2,850 $ $1, Hay Hayward Shop Shop 87,900 $ $86, Hay Hayward Store Room Storage 37,440 $ $7, Richmond S & I 23 Rich Bldg / Shop Service 40,320 $ $19,315 2 Lake Merritt Admin 26 Oak Bldg (LMA) Office 83,520 $ $25, Oak Metro Center Office 160,580 $ $27, Oak 29 Oak 30 Oak 31 Oak 32 Hay 33 Rich 35 Conc 36 Daly 37 Conc Oakland Shop "Maint. of Way Facility" Shop 34,200 $ $11, Oakland Annex "Maint. Facilities Bldg" Shop/office 50,800 $ $17, Oakland Shop "Kaiser Bldg" Shop/store 3,388 $ $1,355 5 Oakland Store Room/Training Bldg Store/training 25,256 $ $8, Hayward Station Parking Structure Parking 38,220 $ $29, El Cerrito Del Norte Sta Parking Parking 388,640 $83.62 $32, Walnut Creek Station Parking Parking 362,464 $93.25 $33, Daly City Station Parking Structure Parking 61,815 $ $28, Concord Station Parking Structure Parking 346,656 $65.63 $22,750 50

49 Ranking of Building Retrofits - Part 2 Number Description LS Retrofit $K Non Structural Retrofit $K Retrofit ($ / sq ft) Benefits (No LS) $ Benefits (LS) $ Benefits (Total) $ BCR 7% 1 Colma(Daly City) Transportation Bldg $300 $39 $29.51 $77,621 $16,290 $93, Daly City Shop $600 $78 $29.53 $300,869 $134,897 $435, Daly City S & I Bldg (Premaint. bldg) $100 $10 $38.48 $36,192 $6,745 $42, Hayward Shop $2,000 $298 $26.14 $3,933,318 $241,178 $4,174, Hayward Store Room $500 $127 $16.74 $266,085 $46,482 $312, Richmond S & I Bldg / 23 Shop $700 $137 $20.75 $1,307 $6,144 $1, Lake Merritt Admin Bldg 26 (LMA) $4,700 $283 $59.66 $1,724,529 $614,829 $2,339, Metro Center $2,800 $544 $20.83 $1,375,667 $437,007 $1,812, Oakland Shop "Maint. of Way Facility" $500 $116 $18.01 $830,577 $82,896 $913, Oakland Annex "Maint. Facilities Bldg" $400 $172 $11.26 $1,741,538 $135,691 $1,877, Oakland Shop "Kaiser Bldg" $1,000 $11 $ $404,805 $75,028 $479, Oakland Store Room/Training Bldg $500 $86 $23.19 $539,558 $39,558 $579, Hayward Station Parking Structure $2,000 $20 $52.85 $834,684 $60,610 $895, El Cerrito Del Norte Sta Parking $3,000 $20 $7.77 $1,790,594 $110,649 $1,901, Walnut Creek Station Parking $2,000 $20 $5.57 $897,571 $30,029 $927, Daly City Station Parking Structure $1,500 $20 $24.59 $709 $141 $ Concord Station Parking Structure $2,000 $20 $5.83 $679,852 $30,029 $709,

50 Loss of Service: Economic Impacts Seismic Damage Results in Loss of Ridership Damage to links or nodes in BART system Damage pattern is inherently probabilistic and cannot be predicted exactly for any earthquake Service restoration depends on:» damage extent and pattern» size of repair crews, available equipment etc.» prioritization set by BART

51 Restoration Patterns Modeling Loss of Ridership vs. Time Consider 8 sections of overall BART system:» A-line (A10-A90)» C-line (C20-C80)» L-line (L10-L40)» M-line (including M16-W10)» R-line (R10-R60)» Wye and core of system: M10, A10, K10, K20, K30, C10» C10-C20 Berkeley Hills Tunnel» M10-M16 Transbay Tube

52 Restoration Patterns Aggregate average daily ridership by these 8 sections of BART 1) trips within a section (e.g., entire trip on A-line) 2) trips between sections (A-line to C-line) 3) consider all combinations to aggregate all BART riders into an 8x8 matrix of origin and destination sections. 4) for loss of ridership calcs, assume that 75% of displaced BART riders use alternatives (cars) and 25% use bus bridges.

53 Hayward M 7 Earthquake BART System Condition Direct Damage ($ Millions) Lost Riders (Millions) Sites with Significant Life Safety Impact Status Quo $1, Package 1 "LS" Package 2 "PO-1" Package 3 "PO-2" Package 4 "PO-3" Package 5 "FO" Package 6 "XO" Unmitigated Life Safety Sites: Hayward Fault Crossings (2 in Tunnel, 2 at Grade)

54 San Andreas M 8 Earthquake BART System Condition Direct Damage ($ Millions) Lost Riders (Millions) Sites with Significant Life Safety Impact Status Quo $ Package 1 "LS" Package 2 "PO-1" Package 3 "PO-2" Package 4 "PO-3" Package 5 "FO" Unmitigated Sites: Calaveras Fault Crossing (At Grade)

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56 Summary How much seismic retrofit is the right amount? For BART, with 1000 s of components where just one failure can lead to a long term functional outage, the tails of the distribution (level of ground motion, capacity of structure) are very important Full retrofit to the highest performance goal for every component has BCR << 1. Fixing the core BART system to the highest performance goal is economically justified. Some outages are still expected

57 Real Time Shakemaps SERA model reads in Shakemaps SERA produces near real time damage forecasts SERA tells where inspections should be done, if at all (damage threshold set at 10% chance of serious damage invokes inspection and shutdown of trains)

58 Moraga M 3.7 (March 21, 2006)

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60 SERA in Design Process Issues As design proceeds, level of detail explodes How to track? RDMS Example covers non-structural items in BART

61 Non-Structural Components 26,696 items 15,321 items Category 1 (OK) 10,247 items Category 2 (Fix) 1,071 items Category 3 (Check)

62 Category 2 Components 10,247 items 1,685 2A - Essential 175 2B - Life Safety 2,168 2C - 2 over 1 6,219 2D - Housekeeping

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64 Fragility Database

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67 SERA in Final Design Decision Process $2M The issue is how much money to spend, how to optimize the upgrade effort to get the most bang for the buck

68 Any Questions?