DAYS: e 90 12 150 186 218 240 27 3 330 365 Elapsed Time in Days Figure B-65 Residual capacity for transmission aqueducts (NEHRP Map Area: California 3-6, California 7, Non-California 7, and Puget Sound 5).
Transmission Aqueduct 68 90 1201 158 180 218 240 278 308 330 365 Elapsed Time in Days Figure B-66 Residual capacity for transmission aqueducts (All other areas).
ATC-25 Appendix B: Lifeline Vulnerability Functions Appendix B: Lifeline Vulnerability Functions 249 comprise shear-wall-type buildings, intake water, and these structures should be built structures, pump and motor units, pipes, on stable soil. Also, pumps and heavy valves, and associated electrical and control equipment should be provided with positive equipment. Requirements vary from small means (anchorage) of resisting lateral units used to pump only a few gallons per forces; base isolators should be used only minute to large units capable of handling when adequate snubbers are provided several hundred cubic feet per second. Buildings enclosing plant equipment should Vertical turbine (most common) and be designed with seismic provisions of local displacement pumps are the two primary or national building codes. The casings of types used. Horizontal centrifugal pumps, wells should be separated from the pump air-lift and jet pumps, and hydraulic rams are house by at least 1 inch to allow for relative also used in special applications. Centrifugal movement and settlement. Pumps that are pumps have impellers, which impart energy hung from the motor at the top of the well to the water. Displacement pumps are by a non-flexible drive shaft inside the pump commonly the reciprocating-type where a column are not recommended. Submersible piston draws water into a closed chamber motor-driven, vertical turbine pumps do not and then expels it under pressure. Pumps require the long drive shaft, and the need may be in series or in parallel. Often an for a perfectly straight well casing is emergency power supply comprising a therefore eliminated. Horizontal pumps and standby diesel generator, battery rack, and their motors should be mounted on a single diesel fuel tank is included in primary foundation to prevent differential pumping stations to operate in emergency movement. Provisions for emergency power should be made for pump stations critical to situations when electric power fails systems operation.
Typical Seismic Damage: Pumping stations will suffer damage closely related to the 1. Direct Damage performance of the soils on which they are constructed. Intake structures are typically Basis: Damage curves for pumping stations tower-type structures that are vulnerable to for the water system are based on ATC-13 inertial effects, and settlement and data for FC 10, medium-rise reinforced landslides at bottoms of reservoirs and masonry shear wall buildings; FC 66. Toppling of these towers allows electrical equipment, and FC 68, mechanical coarse sediment to enter the distribution equipment (see Figure B-67). FC 10 was system, plugging pipelines and causing chosen to represent a generic building, based on review of damage curves for all extensive damage to pump bearings and seals. Piping attached to heavy pump buildings. Pumping stations are assumed to structures is susceptible to damage caused be a combination of 30% generic buildings, by differential settlement. Unanchored 20% electrical equipment, and 50% electrical and control equipment may be mechanical equipment severely damaged. Pumps with long shafts may suffer misalignment, and shafts may be Standard construction is assumed to cracked or sheared by ground movement. represent typical California pumping Pipe hangers may be damaged by relative stations for water systems under present settlement of building and associated conditions (i.e., a composite of older and equipment. Damage to substation more modern stations). Only minimal transformers can result in the loss of power. regional variation in construction quality of mechanical equipment is assumed, as Seismically Resistant Design: Seismically operational loads frequently govern over resistant design practice includes avoiding seismic requirements.
unstable soils in siting the pumping stations, or providing foundations for structures and Present Conditions: In the absence of data equipment capable of resisting expected soil on the type of pumps, age, etc., the failures without damage. Design of intake following factors were used to modify the mean curves for each of the three facility
structures should consider inertial forces developed from self-mass and surrounding Appendix B: Lifeline Vulnerability Functions ATC-25 Pumping Station (Water Supply) Dz=100/ I0 H-60' 0.5a 66 0.20 Other CD 6; (a N-CA? 36 'A 5 VI VIII Ix X Modified Mercalli intensely (MMI) Figure B-67 Damage percent by intensity for water supply pumping stations classes listed above, under present B.6.3 Storage Reservoirs conditions: 1. General MM Intensity Description: In general, storage reservoirs
Shift for the water system comprise earth fill, NEHRP Map Area FC I OFC66 FC 68 rock fill, or concrete dams with gates, California 7 o 0 1 spillways, conduit, tunnels, and intake California 3-6 +1 +1 structures. Earth fill dams include an
Non-California 7 +1 +1 Puget Sound 5 
*+1 +1 impervious, core, typically a clay material, A1Iother areas +2 +2 +1 transition zones, drains, and sand filters adjacent to the core. Grout is frequently Upgraded Conditions: For areas where it provided under the impervious core in the appears cost-effective to improve facilities, foundation material, and in the abutments assume on a preliminary basis that upgrades to prevent water penetration through cracks and fissures in bedrock or flow through result in one or two beneficial intensity shifts (i.e., -or -2), relative to the above permeable native soils. Rock fill dams present conditions typically have concrete linings to prevent water penetration. Concrete dam types Time-to-restoration: The time-to-include gravity and arch. Roadways and/or restoration data assigned to SF 30b, gantry cranes are commonly located at the pumping stations for water systems, are crest of the dam.
assumed to apply to all pumping stations. By combining these data with the damage Typical Seismic Damage: Most engineered, curves derived using the data for FC 10, 66, mechanically compacted earth fill dams have and 68, the time-to-restoration curves shown performed well in earthquakes. Additionally, in Figures B-68 through B-70 were derived. earth fill dams, constructed predominantly ATC-25 Appendix B: Lifeline Vulnerability Functions R=1800 1.00 10 0.30 Go 0.so 66 0.20 M1i1 a b 6 0.223 0.165 7 0, 190 8.876 8 0.142 0.036 9 0. 18 0.021
DAYS: 30 60 90 120 150 180 210 248 270 388 330 365 Elapsed Time in Days Figure B-68 Residual capacity for water supply pumping stations (NEHRP California. 7).
Pumping Station (Water Supply) 1.00 10 8.30-R=1 r 3Bb 68 8.58 66 0.20 11111 a b 6 0 .156 0.044 7 0.122 0, 026 8 0.092 0.017 .
9 0.064 0.012
R= 0/. I II I I I DAYS: 30 60 120 158 180 210 240 270 3 338 365 Elapsed Time in Days Figure B-69 Residual capacity for water supply pumping stations (NEHRP Map Area 3-6, Non-California 7, and Puget Sound 5).
Appendix B: Lifeline Vulnerability Functions ATC-25 Pumping Station (Water Supply) OCR. D-4 GO1. 3GO. 1tR R an SA : 30 60 90 128 190 188 218 240 278 308 338 365 Elapsed Time in Days Figure B-70 Residual capacity for water supply pumping stations (All other areas) with clayey soils have performed well. Dams Settlement of rock fill dams is also a constructed of hydraulic fill using saturated, possibility. Concrete dams have also poorly compacted, fine-grain cohesion less performed well with little damage known.
material; dams constructed on natural Cracking of dams and foundation failures cohesion less deposits that are not as dense are possible.
as the embankments; and dams with unusually steep embankments have Seismically Resistant Design: Seismically experienced failures in past earthquakes. resistant design practices for earth fill dams, Dam embankments may respond to soil include providing ample freeboard to allow failures by cracking (usually at the crest or for settlement and other movements, and near the crest and abutments), spreading or using wide cores and transition zones settling, or by slope stability failures. or zonal constructed of material resistant to cracking separations. Liquefaction may occur in Current design typically used dynamic
saturated zones of cohesion less materials analyses for all but small dams on stable that are loose or marginally compacted, such foundations. These analyses are used to as hydraulic fills. Both soil and rock determine the liquefaction or strain foundations may be damaged by fault potential of embankments and foundations, rupture, resulting in loss of continuity or and to estimate the settlement of integrity of internal design features, (drains, embankments. Conservative crest details imperious zones, etc.) and water-release include providing transition and shell zones features (conduit and tunnels). Earthquake-that extend to the crest to control any induced landslides may block water outlet seepage that develops through cracks, and features or spillways, Or cause waves that providing camber for static and dynamic overtop the dam and cause erosion. Where settlement. Conservative zoning consists of cracks are opened in the embankment or providing confined clay cores, wide foundation, the danger of piping exists if cohesion less transitions, and free draining
cracks remain open. Rock fill dams have shells. Reduction of embankment slopes and performed well, with some damage to elimination of embankment saturation material near the crest of the dam. through linings can reduce susceptibility to ATC-25 Appendix B: Lifeline Vulnerability Functions 253 B: Lifeline Vulnerability Functions 253 Storage Reservoir 35 0.50-36 a.5 a) E CZ Other 0a VI I Vi Ix X Figure B-71 Damage percent by intensity for storage reservoirs.
embankment failures. Seismically resistant Rock fill, then the appropriate damage curves design of concrete dams includes thorough will need to be developed (see ATC-13).
foundation exploration and treatment, and selection of a good geometrical Standard construction is assumed to configuration. Dynamic analyses similar to represent typical California reservoirs (i.e., a those used for earth fill dams may be used to composite of older and more modern check designs, and to determine stresses and reservoirs).
cracking potential of dams and dam appurtenances. Effective quality control is Present Conditions: In the absence of data necessary in the design and construction of on the type of construction, age, etc., the all dams. Stabilization of existing dams can following factors were used to modify the be achieved by buttressing, draining, or mean curves for each of the two facility reduction in reservoir storage. Potentially classes listed above, under present liquefiable soils have been densified by conditions: blasting, vibratory probing, adding backfill, MM/
and driving compaction piles. Intensity Shift
1. Direct Damage NEHRP Map Area FC35 FC36 Basis: Damage curves for storage reservoirs California 7 Oo 0 in the water supply system are based on California 3-6 0 0 Non-California 7 +1 +1
ATC-13 data for FC 35, concrete dams, and Puget Sound 5 +-1 +1 FC 36, earth fill or Rock fill dams (see Figure All other areas +2 +2 B-71). Storage reservoirs are assumed to be a combination of 50% concrete dams and Upgraded Conditions: For areas where it 50% earth fill or Rock fill dams. If inventory appears cost-effective to improve facilities, data identify dams as concrete, or earth fill or assume on a preliminary basis that upgrades B: Lifeline Vulnerability Functions ATC-25 254 Appendix B, Functions ATC-25 age C14
1.a INs au U.JU 38 8.58 li aL b 0.871 8.537 7 8D865 8 e . 94 
*0 9 2.866e.833
IC r= z. Il t l k : Il ij l lS DAYS: 0 60 90 128 158 1B 218 248Z 78 388 330 365 Elapsed Time in ays Figure B-72 Residual capacity for storage reservoirs (NEHRP California 7). result in a beneficial intensity shift of one requires the most Types of water treatment unit (i.e., -1), relative to the above present plants include aeration, split treatment, or conditions. chemical treatment plants. Flexibility and room for growth are typically provided to Time-to-restoration: The time-to-handle changing quality of water.
restoration data assigned to SF 30c, storage Consequently, plants commonly contain reservoirs for water supply systems, are components of different vintages and assumed to apply to all storage reservoirs. Construction types. Current pre-treatment By combining these data with the damage processes are screening, pre-sedimentation curves derived using the damage data for FC or desilting, chemical addition, and aeration 35 and 36, the time-to-restoration curves Components in the treatment process shown in Figures B-72 through B-74 were include pre-sedimentation basins, aerators, derived. detention tanks, flocculators, clarifiers, backwash tanks, conduit and channels, coal B.6.4 Treatment Plants sand or sand filters, mixing tanks, settling tanks, clear wells, and chemical tanks.
1. General Processes used for flocculation include paddle (most common in modem facilities), Description: Water treatment plants are diffused air, baffles (common in older complex facilities. In general, the typical facilities), transverse or parallel shaft mixers, water sources for a treatment plant are vertical turbine mixers, and walking-beam-shallow or deep wells, rivers, natural lakes, type mixers. Sedimentation basin and impounding reservoirs. Treatment construction may vary from excavation in processes used depend on the raw-water the ground to a structure of concrete or source and the quality of finished water steel construction. Most modern desired. Water from wells typically requires sedimentation basins are circular concrete the least treatment, and water from rivers tanks (open or covered), equipped with ATC:-25 Appendix B: Lifeline Vulnerability Functions Storage Reservoir I -30c, 1.00 co o R= 5O .D a)
Ir: R= 0;/ 1 DAYS: 3068 98 120 150 188 218 ; 40 278 300 338 365 Elapsed Time in Days Figure B-73 Residual capacity for storage reservoirs (NEHRP Map Area: California 3-6, Non-California 7, and Puget Sound 5).
Storage Reservoir coma 2 R=_SOV :3, C, En .R= Ox DAYS: 30 68 90 120 158 188 218 Z40 270 308 330 365 Elapsed Time in Days Figure B-74 Residual capacity for storage reservoirs (All other areas).
256 Appendix B: Lifeline Vulnerability Functions ATC-25 ATC-25 mechanical scrapers for sludge removal Depths typically vary from 8 to 12 feet and diameters from 30 to 150 feet. Sludge processing components include holding tanks and clarifier thickeners. Control equipment, pumps, piping, valves, and other equipment are typically housed in a control building. Yard equipment generally includes transformers and switchyard equipment.
Typical Seismic Damage: Structures and equipment in water treatment plants are vulnerable to settling of foundations, especially when founded on fill. Differential settlement of adjacent structures and components supported on different foundations is a particular problem Pipes are vulnerable at locations where they connect to or penetrate treatment structures. Equipment such as pumps can be damaged by loads imposed by piping when differential settlement occurs. Channels and large conduit connecting processing units are subject to seismic damage from several mechanisms, including differential movement from inertial loading, differential settlement, and increased lateral earth pressures. Liquefaction may cause some underground structures in areas of high groundwater to float. Concrete basins and tanks are subject to cracking and collapse of walls and roofs. Pounding damage or permanent movement may result in the opening of expansion joints in basins.
Within basins, sloshing and wave action, as well as shaking, can damage anchor bolts and support members for reactors and rakes.
Building damage may range from dropped suspended ceilings and cracks in walls and frames to partial and total collapse.
Unanchored or improperly anchored equipment may slide or topple, experiencing damage or causing attached piping and conduit to fail. Damage to substation transformers can result in loss of power supply.
Seismically Resistant Design: Seismically resistant design includes providing capability to bypass plant treatment and to provide emergency chlorination in the event of damage caused by an earthquake. An emergency power system for the chlorine injection, controls, and radios is a minimum and if gravity flow is not possible, sufficient emergency power to provide pumping capacity must be available. Slopes adjacent to the plant should be studied to ascertain their stability, and mitigating measures should be taken if necessary. Damage to channels and conduit can be mitigated by providing wall penetrations that allow for differential settlement. Similarly, flexibility should be provided in connections and piping where they span across expansion joints or between structures on different foundation types. Equipment damage can be reduced by using cast-in-place bolts rather than expansion anchors and using equipment with a low center of gravity.
Equipment and piping should be protected from falling debris. Building design should satisfy the seismic requirements of the local building code, as a minimum. Heavy equipment such as sludge-processing equipment should be located as low as possible in the building. Horizontal tanks on saddles should be restrained to saddles to prevent slippage and rupture of attached piping. Design of equipment immersed in water (e.g., paddles, rakes, baffles) should consider both inertial effects and those due to sloshing of water. Design of such equipment should also consider ease of replacement. Vertical turbine pumps hanging in tanks should be avoided if possible-or designed for seismic loads, as a minimum. Chlorine cylinders should be strapped in place on snubbed chlorine scales. Standard safety and shutdown systems for gas and chemical systems should be installed and properly maintained.
Routine checks are recommended to ensure that valves are operable, and that stockpiles of spare parts and tools are available. Basins or structures founded on separate foundation materials should have separate foundations and should be separated by a flexible joint. All critical piping (exclusive of corrosive chemical systems) should be welded steel.
2. Direct Damage Basis: Damage curves for treatment plants in the water supply system (see Figure B-75) are based on ATC-13 data for C 10, medium-rise reinforced masonry shear wall buildings; C 41, underground liquid storage tanks, and FC 68, mechanical equipment.
ATC-25 Appendix B: Lifeline Vulnerabilitly Functions Treatment Plant (Water Supply) 
E D=S07 3 Other VI VII VIII IX X Modified Mercalli Intensity (MMI) Figure B-75 Damage percent by intensity for water supply treatment plants.
FC 10 was chosen to represent a generic MM/ building, based on review of damage curves Intensity for all buildings. Water treatment plants are Shift assumed to a combination of 20% generic NEHRP Map Area FC 10FC41FC68 buildings, 30% underground storage tanks, California 7 o 0 0 and 50% mechanical equipment. California 3-6 +1 0 0 Non-California 7 +1 0 0 Puget Sound 5 +1 0 0
Standard construction is assumed to All other areas +2 +1 +1 represent typical California treatment plants under present conditions (i.e., a composite Upgraded Conditions: For areas where it of older and more modern treatment appears cost-effective to improve facilities, plants). It is assumed that minimal regional assume on a preliminary basis that upgrades
variation exists in construction quality of result in a beneficial intensity shift of one underground storage tanks and mechanical unit (i.e., -1), relative to the above present equipment. Seismic loads have little impact conditions.
on underground storage tank design, and operational loads often govern over seismic Time-to-restoration: The time-to-requirements in the design of mechanical restoration data assigned to SF 30d, equipment. treatment plants in the water supply system, are assumed to apply to all treatment plants.
Present Conditions: In the absence of data By combining these data with the damage on the type of material, age, etc., use the curves derived using the data for FC 10, 41, following factors to modify the mean curves and 68, the time-to-restoration curves shown for each of the three facility classes listed in Figures B-76 through B-78 were derived.
above, under present conditions: Appendix B: Lifeline Vulnerability Functions ATC-25 5 treatment Plant (Water Supply) H=1EB, 30d1 I.00 18 0.20 68 5.-5 41 0.3fi b
a 8.809 0.W11 7
836 0.172 8 0.865 .858 8. 801 8. 22 18 13.894 8.811, S R= x R =b 
*days R= 13;: DAYS: 3f 68 981 120 150 188 218 240 2 3 38 Elapsed Time in Days Figure B-76 Residual capacity for water supply treatment plants NEHRP California 7). G -a ys+ B= x I I l JAYS: 38 68 98 128 158 188 218 248 270 388 338 35 Elapsed Time in Days Figure B-77 Residual capacity for water supply treatment plants (NEHRP Map Area 3-6, Non-California 7 and Puget Sound 5).
ATC-25 Appendix B: Lifeline Vulnerability Functions Treatment Plant (Water Supply) R-100 1.00 10 0.20 68 3.50 41 0.30 IHHI a b 6 0.051 0.091 7 0.870 0.830 8 0.085 B.01B ._ 9 0.897 0.818 Ca 10 0.106 0. 006 B b 
* da9s + a C)
a) cc n n I I 1-Uio : A U IS: 3 I II I I 11 I I I DAYS: 30 60 90 120 15 180 210 248 270 300 330 365II Elapsed Time in Days Figure B-78 Residual capacity for water supply treatment plants (All other areas).
B.6.5 Terminal Reservoirs Tanks Impounding reservoirs may be lined or unlined, and with or without roofs.
1. General Typical Seismic Damage: Failure modes for Description: In general, terminal reservoirs underground tanks include damage to may be underground, on-ground, or concrete columns that support roofs, elevated storage tanks or impounding sloshing damage to roofs, and cracking of reservoirs. Underground storage tanks are walls. In cases of liquefaction, empty tanks typically reinforced or prestressed concrete can become buoyant and float upward, wall construction with either concrete or rupturing attached piping. Impounding wood roofs. They may be either circular or reservoirs perform similarly to underground rectangular. On-ground water supply tanks. At-ground tanks are subject to a storage tanks are typically vertical anchored variety of damage mechanisms, including, and/or unanchored tanks supported at for steel tanks: (1) failure of weld between ground level. Construction materials include base plate and wall, (2) buckling of tank wall welded, bolted, or riveted steel; reinforced (elephant foot), (3) rupture of attached rigid or prestressed concrete; or wood. Tank piping resulting from sliding or rocking of foundations may consist of sand or gravel, or tank, (4) implosion of tank caused by rapid a concrete ring wall supporting the shell. loss of contents and negative internal Elevated storage tanks consist of tanks pressure, (5) differential settlement, (6) supported by single or multiple columns. anchorage failure or tearing of tank wall, (7) Most elevated tanks are steel and are failure of roof-to-shell connection, (8) generally cylindrical or ellipsoidal in shape. failure of shell at bolts or rivets, and (9) total Multiple-column tanks typically have collapse. Concrete tank failure modes diagonal braces, for lateral loads. Elevated include: (1) failure of columns supporting tanks are more common in areas of flat roofs, (2) spalling and cracking, and (3) terrain. There is large variation in tank sizes sliding at construction joints. Wood tanks (i.e., height and diameter), so volumes range have not performed well in past earthquakes from thousands to millions of gallons. and generally fail in a catastrophic manner.
Appendix B: Lifeline Vulnerability Functions ATC-25 Elevated tanks typically fail as a result of inadequate bracing or struts, although column buckling or anchorage or connection failure (clevises and gusset plates) are common causes. If elevated tank damage exceeds minor bracing or connection failure, damage is usually catastrophic- Piping and other appurtenances attached to tanks can also fail because of tank or pipe motion, causing loss of contents.
Seismically Resistant Design: General Seismically resistant design practices for underground tanks include designing walls for a combination of earth pressures and seismic loads; Densifying the backfill used behind the walls to reduce liquefaction potential; designing columns supporting the roof for seismic loads; tying the roof and walls together; providing adequate freeboard to prevent sloshing against the roof; and recognizing the potential for flotation and providing restraint Control of buoyant forces can be achieved by tying the tank to piles designed to resist uplift, increasing the mass of the tank (e.g., provide overburden on the roof, or providing a positive drainage system. An annular space that permits relative movement should be provided where piping penetrates the wall. Seismically resistant design practices for at ground tanks include the use of flexible piping, pressure relief valves, and well-compacted foundations and reinforced concrete ring walls that prevent differential settlement. Adequate freeboard to prevent sloshing against the roof should be maintained. Good practices, for steel tanks include providing positive attachment between the roof and shell, stiffening the bottom plate and its connection to the shell, protecting the base plate against corrosion, and avoiding abrupt changes in thickness between adjacent courses. Properly detailed ductile anchor bolts may be feasible on smaller steel tanks. For concrete tanks, keying and detailing to prevent sliding is good practice. Columns supporting roofs should be detailed to prevent brittle failures.
In areas where freeze-thaw cycles are a problem, minimum strength requirements that ensure durability should be met. For wood tanks, seismically resistant design practices include increasing hoop capacity, and anchoring or strapping the tank to the foundation. Maintaining a height-to-diameter ratio of between 0.3 and i07 for tanks supported on-ground controls seismic loading. Because the damage to elevated tanks typically involves the supporting structure rather than the supported vessel, the primary Seismically resistant design practices for elevated tanks are design of the braces for adequate lateral loads, providing adequate anchorage at the column bases, connecting the tank to the frames that support it for load transfer, and providing flexibility in the attached piping to accommodate expected motions. The bracing system should be designed to yield prior to connection failure. Rods used for bracing should have upset threads with large deformable washers under retaining nuts to absorb energy.
2. Direct Damage Basis: Damage curves for water supply terminal reservoirs are based on ATC-13 data for FC 43, on-ground liquid storage tanks (see Figure B-79). On-ground storage tanks, are less vulnerable than elevated tanks, and more vulnerable than underground tanks, and were chosen as representative of existing terminal reservoirs. If inventory data identify tanks as underground or elevated, then use FC 41 or 45, respectively, in lieu of FC 43.
Standard construction is assumed to represent typical California terminal reservoirs under present conditions [i.e., a composite of older, non-seismically designed tanks as well as more modern tanks designed to seismic requirements (e.g., AWWA DI00, Appendix A)].
Present Conditions: In the absence of data as to type of material, age etc., use the following factors to modify the mean curves, under present conditions: MMI Intensity NEHRP Map Area Shift California 7 0 California 3-6 +1 Non-California 7 Puget Sound 5 +1 All other areas +2 ATCC:-25 Appendix B: Lifeline Vulnerability Functions 2, 1 Terminal Reservoir (Storage D=180v 43 1.
0) ca D=507 E a Other 1VWII III IX X Modified Mercalli Intensity (MMI) Figure B-79 Damage percent by intensity for water supply terminal reservoirs/storage tanks.
Upgraded Conditions: For areas where it inches or more in diameter) are usually appears cost-effective to improve facilities, welded steel or reinforced concrete and may assume on a preliminary basis that upgrades carry water at high pressures (several result in one or two beneficial intensity hundred psi). Joints in steel pipes may be shifts (i.e., -1 or -2), relative to the above welded or bell-and-spigot types. Except in present conditions. areas of freezing, backfill measured from the pipe crown is typically between 2.5 and 4.5 Time-to-restoration: The time-to-feet. In addition to the pipes themselves, restoration data assigned to SF 30e, terminal trunk lines include a number of other reservoirs for water supply, are assumed to components. Pipelines may require gate apply to all tanks. By combining these data valves, check valves, air-inlet release valves, with the damage curves for FC 43, the time-drains, surge control equipment, expansion to-restoration curves shown in Figures B-80 joints, insulation joints, and manholes through B-82 are derived. Check valves are normally located on the upstream side of pumping equipment and at B.6.6 Trunk Lines the beginning of each rise in the pipeline to prevent back flow. Gate valves are used to 1. General permit portions of pipe or check valves to be isolated. Air-release valves are needed at Description: In general, trunk lines may be the high points in the line to release trapped underground, on-ground, or supported on gases and to vent the lines to prevent elevated frames above ground. However, vacuum formation. Drains are located at low most trunk lines in the water supply system points to permit removal of sediment and are located underground. Pipe materials allow the conduit to be emptied. Surge tanks include cast iron, welded steel, riveted steel, or quick-opening valves provide relief for concrete-lined steel, asbestos cement, and problems of hydraulic surge.
plastic. Newer trunk lines (typically 20 Appendix B: Lifeline Vulnerability Functions ATC-25 Reservoir (Storage Tank), o-4 an AS 4 J. ULJ 6 0.26Z 1.347
R x l I j I T DAYS: 30 60 9 128 1581 1B8 218 24a 278 3 330 Elapsed Time in Days Figure B-80 Residual capacity-for water supply terminal reservoirs storage tanks NEHRP California 7).
Reservoir (Storage Tank) 11aRI ' 4 via
* days + a FU R= 8 I I i i i I I I I I I I I DAYS: 68 90 128 15 113 218 240 278 388 330 365 Elapsed Time in Days Figure B-81 Residual capacity for water supply terminal reservoirs/storage tanks (NEHRP Map Area 36, Non-California 7, and Puget Sound 5).
ATC-25 Appendix B: Lifeline Vulnerability Functions 23 Reservoir (Storage Tank) I AO Ie M MII a b 6 0.258 0.220 7 0.236 0, 870 B 0.002 0.827
.9 -8.413 8.021 (a c) 10 -0.534 .017 o R= S8, :m R b 
1 I I I I I I D-U-AR, U. I I, I I I I I I DAYS: 3 60 90 120 15R 180 210 240 270 300 330 365 Elapsed Time in Days Figure B-82 Residual capacity for water supply terminal reservoirs/storage tanks (All other areas).
Typical Seismic Damage: The performance Seismically Resistant Design: Seismically of pipelines is strongly dependent on 
*resistant design practices for trunk lines whether or not the supporting or include the use of ductile pipe materials, surrounding soil fails. Failure of a piping such as steel, ductile iron, copper, or plastic.
system resulting from inertial loads only is The performance of welded steel pipelines rare; more typically differential settlement is dependent upon the quality of welds, with or severe ground failure (e.g., landslide, more modern pipes generally having liquefaction, faulting) causes damage. superior welds. Use of flexible joints (e.g., Regional uplift can alter the hydraulic bell-and-spigot with rubber gaskets, characteristics of a transmission system mechanical joints, expansion joints, rubber rendering it nonfunctional. Pipe damage is or metallic bellows, and ball joints) and most common in soft alluvial soils or at placement of pipes in dense native or interfaces between soft and firm soils. Types compact soil not subject to liquefaction, of pipe damage include bending or crushing slides, or surface rupture will mitigate much of the pipe, shearing of the pipe, of the potential damage. Special precautions compressional buckling, soil deposits in the should be taken to reduce earthquake pipe, circumferential and longitudinal effects at pumping plants, tanks, bay or river cracks, and joint failure. It has frequently crossings, and fault crossings. Shut-off valves been observed that pipelines with rigid should be installed near active fault zones so joints fail more frequently than those with that flow can be stopped if the pipeline flexible joints. Damage has been substantial crossing is damaged. Trunk lines at fault at locations of local restraint such as crossings should be located in a sacrificial penetrations to heavy subsurface structures tunnel or culvert, or lubricated, wrapped in (including manholes), tees, and elbows. sheathing, or buried in shallow loose fill, Water hammer induced by ground motions installed or above ground near the fault to can cause damage by temporarily increasing allow lateral and longitudinal slippage.
pressure in pipelines. Anchors such as thrust blocks or bends Appendix B: Lifeline Vulnerability Functions ATC-25 trunk Lines bpk=20 .
G E 0) by k=ia m V) bipk=O VI lii VIII Ix Modified Mercalli Intensity (MMI13 Figure B-83 Damage percent by intensity for water supply trunk lines.
should be excluded within a distance of 300 (between 4 and 20 inches in diameter) are feet of a fault zone and strengthened pipe generally mc)re susceptible to damage should be used within the zone. Valve because of their construction type, and it is spacing near fault zones, or in areas of assumed that their behavior can be expected soil failure should be reduced. approximate: d using these data through the Proper maintenance and cathodic use of one detrimental intensity shift (i.e., protection to limit corrosion, which weakens pipes, is important for mitigating damage.
Supports for on- or above ground piping Standard construction is assumed to should provide restraint in all three represent y typical
California trunk lines orthogonal directions by using ring girders, under present conditions (i.e., a composite and spacing between adjacent trunk lines of older and -more modern trunk lines). Only should be sufficient to prevent pounding. minimal regional variation in the Use of pressure relief valves can mitigate construction quality is assumed.
damage caused by water hammer.
Redundancy should be built into the system Present Conditions: In the absence of data whenever possible; several smaller pipes on the type) material, diameter, age, etc., should be used in lieu of one large pipe. Any the following factors were used to modify equipment attached to piping should be the mean curves, under present conditions: properly anchored.
MM/ 2. Direct Damage Intensity NFHRP Map Area Shift California 7 0
Basis: Damage curves for trunk lines in the water supply system are based on ATC-13 California 3-6 0 Non-California 7 0
data for FC 31, underground pipelines (see Puget Sound 5 0
Figure B-83). Distribution pipelines, All other areas +1 ATC:-25 Appendix B: Lifeline Vulnerability Functions >x Trunk Lines.
R2 100 30F 1.00 31 I .00 
*018 MII a b 6 0.002 0.449 7 0.883 8.449 8 8.109 
use I I I I1 I I I I DAYS: 30 68 90 120 150 180 210 Z40 27 3 338 365 Elapsed Time in Days Figure B-84 Residual capacity for water supply trunk lines (NEHRP Map Area: California 3-6, California 7, Non-California 7, and Puget Sound 5).
Upgraded Conditions: It is not cost-B.6. 7 Wells effective or practical to upgrade existing trunk lines in the water supply system, 1. General except perhaps at fault crossings or in areas of extremely unstable soils. Therefore, no Description: The collection of groundwater intensity shifts for retrofitting are is accomplished primarily. through the recommended. construction of wells or infiltration galleries.
A well system is generally composed of three Typical Seismic Damage: The time-to-elements: the well housing structure, the restoration data assigned to SF 30f, trunk motor/pump, and the discharge piping. The lines, are assumed to apply to all trunk lines well system may or may not be located in a in the water supply system. By combining well house. The well contains an open these data with the damage curves for FC section (typically a perforated casing or 31, the time-to-restoration curves shown in slotted metal screen) through which flow Figures B-84 and B-85 were derived enters and a casing through which the flow is Distribution line restoration will take longer transported to the ground surface. Vertical based on prioritization of work. It is turbine pumps are often used for deep wells assumed that restoration of distribution lines will take approximately twice as long as Typical Seismic Damage: Well casings will restoration of trunk lines. move with the surrounding soils. This movement can result in damage to pumps and/or discharge lines without flexible couplings. Additional problems include fluctuation in production (disruption of aquifer), bad sanding conditions due to local soil disturbance (mostly in older wells with Appendix B: Lifeline Vulnerability Functions ATC-25 Trunk Lines 
DAYS: 38 60 90 126 158I 1 216 248 272 380 338 365 Elapsed Time in Days Figure B-85 Residual capacity for water supply trunk lines (All other areas).
insufficient screen design), kinked tubing, equipment should be provided with and collapse of the casing. The well shaft adequate seismic anchorage. The well-can be crushed or sheared off by ground housing structure should be designed with displacement across, the shaft or by ground seismic provisions of local or national vibration. Wells may be contaminated by building codes.
inflow from nearby sewers, septic tanks, and cesspools that are damaged by the 2. Direct Damage earthquake. Damage to substation transformers can result in loss of power Basis: Damage curves for wells in the water supply. supply system (see Figure B-&6) are based on ATC-13 data for FC 68, mechanical Seismically Resistant Design: As seismic equipment. It is believed that this facility design practices may include providing class best approximates the expected double casing at depths below where performance of wells, which typically horizontal movement is expected. comprise a vertical pump in a shaft.
Submersible pumps/motors have a greater probability of remaining in service than do Standard construction is assumed to pumps connected to motors at the surface represent typical California wells under with drive shafts. Because the well casing present conditions (i.e., a composite of older will respond differently than the slab of the and more modern wells). Only minimal surrounding well house, a flexible separation regional variation in the construction quality joint should be provided between the casing is assumed.
and the slab. Effects of differential movement and settlement can be mitigated Present Conditions: In the absence of data by providing a flexible joint between the on the type of pump, etc., the following pump discharge header and the discharge factors were used to modify the mean piping. Other electrical and mechanical curves, under present conditions: ATC-25 Appendix B: Lifeline Vulnerability Functions 68 1.00 0 a) 0) D=SOY V1 1)11 VI11 Ix X Modified Mercalli Intensity (MMI) Figure B-86 Damage percent by intensity for wells.
MMI B.7Sanitary Sewer Intensity NEHRP Map Area Shift B. 7.1 Mains California 7 0 California 3-6 0 1. General Non-California 7 0 Puget Sound 5 0 All other areas +1 Description: In general, mains in the sanitary sewer system are underground Upgraded Conditions: For areas where it pipelines that normally follow valleys or appears cost-effective to improve facilities, natural streambeds. Valves and manholes assume on a preliminary basis that upgrades are also included in system. Pipe materials result in a beneficial intensity shift of one commonly consist of cast iron, vitrified clay unit (i.e., -1), relative to the above present concrete, asbestos cement pipe, brick, and conditions. bituminized fiber. Pipe diameters are generally greater than 4 inches. Joint Time-to-restoration: The time-to-materials include welded bell-and spigot, restoration data assigned to SF 30b, rubber gasket, lead caulking, cement pumping stations in the water supply system, caulking, and plastic compression rings.
are assumed to apply to all wells. By Bolted flange couplings are also sometimes combining these data with the damage used. Manholes are typically provided at curves for FC 68, the time-to-restoration changes in direction or pipe size, or where curves shown in Figures B-87 and B-88 were flow is received from collecting sewers derived. Wastewater pipelines are usually designed as open channels except where lift stations are required to overcome topographic barriers. Sometimes the sanitary sewer Appendix B: Lifeline Vulnerability Functions ATC-25 5 Well -30h 30. a 0L Ii 17 0.2k, 39 0.89 E 56 0.4: 3 28 8.8z C, IE 3E6 0.011) R= 5Ez a ;a I I L R= y I I DAYS: 38 EB 98 i2o 158 is8 218 248 278 38 338 Elapsed Time in Days Figure B-87 Residual capacity for wells (NEHRP Map Area: California 3-6, California 7, Non-California 7, and Puget Sound 5).
R= l S 3I I DAYS: 30 5Q 9l 120; 155 1BO 218 240 278 38 330 365 Elapsed Time in Days Figure B-88 Residual capacity for wells (All other areas).
ATC-25. Appendix B: Lifeline Vulnerability Functions system flow is combined with the storm water system prior to treatment.
Typical Seismic Damage: The performance of pipelines is strongly dependent on whether or not the surrounding soil fails (e.g., landslide, liquefaction, or fault rupture). Pipe damage is most common in soft alluvial soils or at interfaces between soft and firm soils. Failure of piping caused by inertial loads is uncommon. Potential types of damage include pipe crushing and cracking caused by shearing and compression; joint breaking because of excessive deflection or compression; joints pulling open in tension; and changes in sewer grade, causing reduced flow capacity. Tension and compression failures at joints because of soil movement have been common. Flexible joints have suffered significantly less damage than rigid joints.
Welded bell-and-spigot joints have performed poorly when subjected to longitudinal stress. Cast-iron pipes with rubber gaskets or lead-caulked joints have accommodated movements better than those caulked with cement, but may still pull apart with major soil movements.
Seismically Resistant Design: Seismically resistant design practices for mains in the sewer system include the use of flexible joints (e.g., butt-welded and double-welded joints, restrained-articulated joints, and restrained bell-and-spigot joints with ring gaskets on a short length of pipe section), and avoiding longitudinally stiff couplings such as cement or lead-caulked, plain bell-and-spigot, and bolted flange. Placement of mains in dense native or compact soil not subject to liquefaction, slides, or surface rupture will mitigate much of the potential damage. Special precautions should be taken to reduce earthquake effects at fault crossings. Main lines at fault crossings can be located in a sacrificial tunnel or culvert, or lubricated, wrapped in sheathing, buried in shallow loose fill, or installed above ground near the fault to allow lateral and longitudinal slippage. Anchors such as bends should be excluded within a distance of 300 feet of a fault zone and strengthened pipe should be used within the zone. Isolation valves should be placed near fault zones or in areas of expected soil failure. Proper maintenance to limit corrosion of metal pipes, which weakens pipes, is important to mitigate damage. Any equipment attached to piping should be properly anchored.
2. Direct Damage Basis: Damage curves for mains in the sanitary sewer system are based on ATC-13 data for FC 31, underground pipelines (see Figure B-89). In general, mains in the sanitary sewer system are more vulnerable than those used in other systems because of the construction materials used. Unlike the water supply system, larger pipes generally operate at lower pressures and thus are of similar construction quality to the smaller pipes. Consequently, the above damage curves may be used for all pipelines in the sanitary sewer system.
Standard construction is assumed to represent typical California mains in the sanitary sewer system under present conditions (i.e., a composite of older and more modern mains). Only minimal regional variation in the construction quality is assumed.
Present Conditions: In the absence of data on the type of material, diameter, age, etc., the following factors were used to modify the mean curves, under present conditions: MMI Intensity NEHRP Map Area Shift California 7 +1 California 3-6 +1 Non-California 7 +1 Puget Sound 5 +1 All other areas +2 Upgraded Conditions: It is not cost-effective or practical to upgrade existing mains in the sewer system, except perhaps at fault crossings or in areas of extremely unstable soils. Therefore, no intensity shifts for retrofitting are recommended.
Time-to-restoration: The time-to-restoration data assigned to SF 31a, effluent and main sewer lines, are assumed to apply to all distribution lines. By combining these data with the damage curves for FC 31, the time-to-restoration curves shown in Figures Appendix B: Lifeline Vulnerability Functions ATC-25 B: Lifeline Vulnerability Functions: _C bpk=8 VI UVI VIII IX K Modified Mercalli Intensity (MMI) Figure B-89 Damage percent by intensity for sanitary sewer mains/lines.
B-'90 and B-91 were derived. Collector pipe Because of their function, these stations are restoration will take longer because of its typically located in low-lying areas of soft relatively lower priority. It is assumed that alluvium where soil failures may occur restoration of collector lines will take Buildings housing stations may experience approximately twice as long as restoration of generic building damage ranging from the mains cracking of walls and frames to collapse, and unanchored electrical and mechanical B. 7.2 Pumping Stations control equipment may topple and slide, experiencing damage and tearing piping and 1. General conduit connections. Piping attached to heavy pump/motor equipment structures is Description: Pumping stations or lift susceptible to damage caused by differential stations are typically used to transport settlement. Pumps/motors may also accumulated wastewater from a low point in experience damage as a result of differential the collection system to a treatment plant. settlement. Damage to substation Pumping stations consist primarily of a wet transformers can result in a loss of power well, which intercepts incoming flows and supply.
permits equalization of pump loadings, and a bank of pumps, which lift the wastewater Seismically Resistant Design: Seismically from the wet well. The centrifugal pump resistant design practice includes avoiding finds widest use at pumping stations. Lift unstable soils whenever possible and stations are commonly located in small, addressing problems of expected differential shear-wall-type buildings. settlement and liquefaction in the design of foundations. Flexibility of pipelines should Typical Seismic Damage: Pumping stations be provided when pipes are attached to two will suffer damage closely related to the soil separate structures on different foundations.
materials on which they are constructed. Annular space should be provided at pipe ATC-25 Appendix B: Lifeline Vulnerability Functions Ha ins/Lines
*b 6 -8.517 0.355 7 -0.173 0.134 B -8.244 0.161 (a 9 -8.861 0 .855 (a 10 0.029 H.026 t) R=5v -R = b 
i i i I I I DAYS: 30 60 9gY 128 150 180 210 Z48 270 300 330 365 Elapsed Time in Days Figure B-90 Residual capacity for sanitary sewer mains/lines (NEHRP Map Area: California 3-6, California 7, Non-California 7, and Puget Sound 5).
Hains/Lines 1II u 1 R R -B. 09? 0.013 ('3
0-0 R= 50:v co R = b days a :a
BR=O I i I I I I I I i DAYS: 30 6 90 120 150 180 210 240 270 300 330 365 Elapsed Time in Days Figure B-91 Residual capacity for sanitary sewer mains/lines (All other areas).
Appendix B: Lifeline Vulnerability Functions ATC-25 Pumping Station Sanitary Sewer) D4Ei117 Other
C UI JII IX X Modified Mercalli intensity (MMi) Figure B-92 Damage percent by intensity for sanitary sewer pumping stations.
penetrations in massive structures. to below for mechanical and electrical prevent pipe damage in the event of equipment is assumed appropriate.
differential settlement. All mechanical and electrical equipment should be anchored Standard construction is assumed to and equipment on isolators properly represent typical California pumping snubbed. Buildings housing equipment stations for sanitary sewer systems under should be designed in accordance with present conditions (i.e., a composite of older seismic provisions of a local or national and more modern stations). Only minimal building code. Provisions for emergency regional variation in construction quality of power should be made for pumping stations mechanical equipment is assumed.
critical to systems operation.
Present Conditions: In the absence of data 2. Direct Damage on the type of pumps, age, etc., the following factors were used to modify the Basis: Damage curves for pumping stations mean curves, for each of the three facility for the sanitary sewer system (see Figure B-classes listed above, under present 92) are based on ATC-13 data for FC 10, conditions: medium-rise reinforced masonry shear wall buildings; FC 66, electrical equipment, and MMI FC 68, mechanical equipment (see attached intensity figure). FC 10 was chosen to represent a Shift generic building, based on review of damage NEHRP Map Area FC 10FC 66FC 68 curves for all buildings. Pumping stations are California 7 0 0 +1 assumed to be a combination of 30% California 3-6 +1 +1 +1 generic buildings, 20% electrical equipment, Non-California 7 +1 +1 +1 Puget Sound 5 +1 +1 +1
and 50% mechanical equipment. Pumping All other areas +2 +2 +2
plants in the sewage system are assumed to be located in poor soil areas. Consequently, the detrimental intensity shift indicated ATC-25 Appendix B: Lifeline Vulnerability Functions Pumping Station (Sanitary Sewer) RAHt8Wz 31b 1.00 1 0.30 60 0.50 166 0.20 M111 a b 6 -0.146 0. 182 7 -0.189 0, 887 8 -0.232 0.043 
*0 Ma 0: ) B= 50x 9 10 -8.261 -0.280 0.026 1.018 R = b 
* days a -DIr0) B= DAYS: 3 68 90 120 ISO 180 210 240 27 3 330 365 Elapsed Time in Days Figure B-93 Residual capacity for sanitary sewer pumping stations (NEHRP California 7).
Upgraded Conditions: For areas where it circulation and wastewater pumping appears cost-effective to improve facilities, stations, chlorine storage and handling, assume on a preliminary basis that upgrades tanks, and pipelines. Concrete channels are result in a beneficial intensity shift of one frequently used to convey the wastewater unit (i.e., -1), relative to the above present from one location to another within the conditions complex. Within the buildings are mechanical, electrical, and control Time-to-restoration: The time-to-equipment, as well as piping and valves.
restoration data assigned to SF 31b, booster Conventional wastewater treatment consists pumping and main sewer pumping stations, of preliminary processes (pumping, are assumed to apply to all pumping stations screening, and grit removal), primary settling in the sanitary sewer system. By combining to remove heavy solids and floatable these data with the damage curves derived materials, and secondary biological aeration using the data for FC 10, 66, and 68, the to metabolize and flocculate colloidal and time-to-restoration curves shown in Figures dissolved organics. Waste sludge may be B-93 through B-95 were derived. stored in a tank and concentrated in a thickener. Raw sludge can be disposed of by B.7.3 Treatment Plants anaerobic digestion and vacuum filtration, with centrifugation and wet combustion also 1. General currently used. Additional preliminary treatments (flotation, flocculation, and Description: Treatment plants in the chemical treatment) may be required for sanitary sewer system are complex facilities industrial wastes. Preliminary treatment which include a number of buildings units vary but generally include screens to (commonly reinforced concrete) and protect pumps and prevent solids from underground or on-ground reinforced fouling grit-removal units and flumes concrete tank structures or basins. Common Primary treatment typically comprises components at a treatment plant include sedimentation, which removes up to half of trickling filters, clarifiers, chlorine tanks, re-the suspended solids. Secondary treatment ATC-25 Appendix B: Lifeline Vulnerability Functions ATC-25 a-R, Pumping Station (Sanitary Sewer) Q1 L 4 00 s I . 11 . i-. -I-Go 8.53 66 0.20 mfl a b 6 -0. 163 3. 131 7 -0 .216 8 -8.24B 0. 833 9 -8.272 2.821 0 18 -H.2RB O. 815 U E= 0Z co r42 R =b 
* days + e0 i l l l l | E
R= O/x I I I II-I| I DAYS: 30 68 98 128 158 18 218 248 Z78 388 330 365 Elapsed Time in Days Figure B-94 Residual capacity for sanitary sewer pumping stations (NEHRP Map Area: California 3-6r Non-California 7, and Puget Sound 5.
Pumping Station (Sanitary Sewer), 1 L 4 i} 1 -i-R m R = b 
* a B= 8ot i Il Iil l Il DAYS: 30 68 98 128 158 188 210 240 278 308 338 365 Elapsed Time in Days Figure B-95 Residual capacity for sanitary sewer pumping stations (All other areas).
Appendix B: Lifeline Vulnerability Functions
ATC-25 . B: Lifeline Vulnerability Functions 275 removes remaining organic matter using activated-sludge processes, trickling filters, or biological towers. Chlorination of effluents is commonly required.
Typical Seismic Damage: Sanitary sewer treatment plants are commonly located in low-lying areas on soft alluvium.
Consequently, soil failure (e.g., liquefaction or settlement) is common. Many of the heavy structures are supported on foundations that include piles. Differential settlements between these structures and structures not supported on piles will result in damage to pipes or conduit, especially at structure penetrations. Liquefaction may cause some underground structures to float in areas of high groundwater. Pumps and other equipment can be damaged by loads imposed by piping when differential settlement occurs. Generic building damage ranging from cracked walls and frames to collapse may occur. Unanchored equipment may slide or topple, rupturing attached piping and conduit. Damage to substation transformers can result in a loss of power supply. Damage as the result of sloshing or wave action is likely in basins that contain rotating equipment or other moving devices Basin walls may crack or collapse. Pounding 
damage or permanent movement may result in the opening of expansion joints in basins.
Seismically Resistant Design: Seismically resistant design practice includes siting treatment plants in areas of stable soil, or designing foundations and systems to perform adequately in the event of expected soil failure. Each structure should be supported on one foundation type only if adjacent structures have different foundation types; structures should be adequately separated; and piping and other systems spanning between structures should be provided with adequate flexibility to accommodate relative motions. Piping should be provided with annular space where it penetrates heavy structures to accommodate settlement. Buildings should be designed in accordance with the seismic requirements of a local or national building code. Walls for all basins should be designed for a combination of soil and hydrodynamic pressures, taking into consideration the possibility of soil failure. All backfills should be compacted properly to avoid liquefaction.
If buoyant loading is possible, foundations should be designed to resist such loading.
All equipment should be properly anchored, and equipment on base isolators properly snubbed. Arms, rakes, and other equipment in basins should be designed for hydrodynamic forces associated with sloshing. Embankment stability and considerations for buried piping should be taken into account for sewage outfalls.
Outfall diffusers are also subjected to hydrodynamic forces, which should be included in design consideration.
2. Direct Damage Basis: Damage curves for treatment plants in the sanitary system are based on ATC-13 data for FC 10, medium-rise reinforced masonry shear wall buildings; FC 41, underground liquid storage tanks; and FC 68, mechanical equipment (see Figure B96).
FC 10 was chosen to represent a generic building, based on review of damage curves for all buildings. Sanitary sewer treatment plants are assumed to a combination of 20% generic buildings, 30% underground storage tanks, and 50% mechanical equipment. Treatment plants in the sewage system are assumed to be located in poor soil areas. Consequently, the detrimental intensity shift indicated below for mechanical equipment is assumed appropriate.
Standard construction is assumed to represent typical California treatment plants under present conditions (i.e., a composite of older and more modern treatment plants). It is assumed that minimal regional variation exists in construction quality of underground storage tanks and mechanical equipment. Seismic loads have little impact on underground storage tank design, and operational loads often govern over seismic requirements in the design of mechanical equipment.
Present Conditions: In the absence of data on the type of construction, age, etc., the following factors were used to modify the mean curves for each of the three facility classes listed above, under present conditions: Appendix B: Lifeline Vulnerability Functions ATC-25 Treatment 60 8.50 41 al30 E a D=Cx HI 14ll IX X Modified Mercalli Intensity {MMI} Figure B-96 Damage percent by intensity for sanitary sewer treatment plants.
MM B.8Natural Gas intensity Shift B.8.1 Transmission Lines NEHRP Map Area FC 18FC41 FC 68 California 7 o +1 +1 1. General California 3-6 +1 +1 +1 Non-California 7 +1 +1 +1 Puget Sound 5 +1 +1 +1 Description: In general, transmission lines All other areas +2 +2 +2 in the natural-gas system are located underground, except where they cross rivers Upgraded Conditions: For areas where it or gorges, or where they emerge for appears cost-effective to improve facilities, connection to compressor or pumping assume on a preliminary basis that upgrades stations. They are virtually always welded result in a beneficial intensity shift of one steel and operate at high pressures.
unit, relative to the above present. Transmission pipelines range between 2 and conditions. 25 inches in diameter, but most are larger than 12 inches. Shut-off valves, which Time-to-restoration: The time-to-automatically function when line pressure restoration data assigned to SF 3, drops below a certain threshold pressure, treatment plants in the sanitary sewer are frequently included.
system, are assumed to apply to all treatment plants- By combining these data Typical Seismic Damage: The performance with the damage curves derived using data of pipelines is strongly dependent on for FC 1 41, and 68, the time-to-whether or not the supporting soil fails, restoration curves shown in Figures B-97 Routes are often selected along the edges of through B-99 were derived. river channels to avoid urban buildup and street crossings and to simplify the acquisition of real estate. Such routes have high liquefaction potential. Failures in the past have typically occurred at sharp vertical ATC-25 Appendix B: Lifeline Vulnerability Functions RzI6W.v .0 CII
0 H: 0, % -o 'a a) cc H=8% DAYS: 36 Go 90 120 ISO 18O 210 240 270 386 338 365 Elapsed Time in Days Figure B-97 Residual capacity for sanitary sewer treatment plants (NEHRP California 7).
0 a) a:, R2: a DAYS: 36 60 90 120 ISO 186 216 240 276 300 338 365 Elapsed Time in Days Figure B-98 Residual capacity for sanitary sewer treatment plants (NEHRP Map Area 3-6, Non-California 7, and Puget Sound 5).
278 B: Lifeline Vulnerability Functions ATC-25
Appendix AC2 2-, Q R= sox CR ox DAYS: 3 -98 128 150 1BO; 218 24 278 388 338 365 Elapsed Time in Days Figure B-99 Residual capacity for sanitary sewer treatment plants (All other areas) or lateral dislocations or ruptures of the Special precautions should be taken to ground. Pipes may buckle under reduce earthquake effects at bay, river, and compressive forces, especially where they fault crossings. Transmission lines at fault cross ruptured faults. Damage has also crossings should be buried in shallow loose occurred as a result of axial elongations fill or installed above ground near the fault caused by relative movement of two to allow lateral and longitudinal slippage.
horizontally adjacent soil layers. Damage Anchors such as thrust blocks or bends may occur because of displacements of should be excluded within a distance of 300 unanchored compressors or pumps or other feet of a fault zone, and strengthened pipe above ground structures. Several past should be used within the zone. Valve failures have been attributed to corrosion spacing near fault zones or in areas of combined with surges in line pressure during expected soil failure should be reduced the earthquake. Failures of above ground Automatic shut-off valves should not rely on lines have been caused by support failure, electricity to operate. Proper maintenance failure of pipeline attachment to support to limit corrosion, which weakens pipes, is structure, and relatively large support important to mitigate damage movement. Rupture of pipes and loss of contents could lead to fire and explosions. 1. Direct Damage Seismically Resistant Design: Modern high-Basis: Damage curves for transmission lines pressure gas lines provided with proper full in the natural-gas system are based on ATC-penetration welds and heavy walls are very 13 data for FC 31, underground pipelines ductile and have considerable resistance to (see Figure B-1lO). Transmission pipelines earthquake damage. Welded steel pipeline are typically large-diameter, welded steel performance depends on the integrity of the pipes that are expected to perform in welds-modern butt-welded pipelines earthquakes in a manner superior to that of perform well, whereas gas lines constructed typical underground pipelines, as indicated before and during the early 19310susing by the beneficial intensity shift below oxyacetylene and electric-arc welds do not.
ATC-25 Appendix B: Lifeline Vulnerability Functions 279: Transmission Lines (Natural Gas) byk=20 31 1.00-VI VII VIII Ix Non-CA 7 P.S. 5 X Modified Mercalli Intensity (MMI) LireB-100Figi Damage percent by intensity for natural gas transmission lines.
Standard construction is assumed to intensity shifts for
* retrofitting are represent typical California natural-gas recommended.
transmission lines under present conditions (i.e., a composite of older and more modern Time-to-restoration: The time-to-transmission lines). Only minimal regional restoration data assigned to SF 32a, variation in the construction quality is transmission lines, are assumed to apply to assumed. all transmission lines in the natural-gas system. By combining these data with the damage curves for FC 31, the time-to-Present Conditions: In the absence of data on the type of material, diameter, age, etc., restoration curves shown in Figures B-101 and B-102 were derived.
the following factors were used to modify.
the mean curves, under present conditions: B.8.2 Compressor Stations MMI Intensity 1. General NEHRP Map Area Shift California 7 -1 Description: In general, compressor stations California 3-6 -1 include a variety of electrical and Non-California 7 -1 mechanical equipment, as well as structures Puget Sound 5 -1 and buildings. A typical plant yard may
All other areas 0 contain electrical equipment, heat Upgraded Conditions: It is not cost-exchangers, horizontal gas-storage tanks on effective or practical to upgrade existing plinths, compressors, fans, air-operated natural-gas transmission lines, except valves, pumps, cooling towers, steel stacks perhaps at fault crossings or in areas of and columns, and piping. The control extremely unstable soils. Therefore, no equipment is usually located in a control building. Cryogenic systems may also exist Appendix B: Lifeline Vulnerability 
Transmission -32a Lines (Natural l.1E 31 X 5a 7 B 0 91 A W Mys'. 30 680 l, 90 l, 120' l, 150 l, 8 lr 218 lr 240 l j 20 30 330 365 Elapsed Time in Days Figure B-1 01 Residual capacity for natural gas transmission lines (NEHRP Map Area: California 3-6, California 7 Non-California 7, and Puget Sound 5).
Transmission Lines (Natural Gas) 12 o4 -g MH I R:= E36e 6h? -8 . 8 -E rU 9 -E (a 
DAYS: 30 80 90 120 15 180 216 240 278 300 330 385 Elapsed Time in Days Figure B-1 02 Residual capacity for natural gas transmission lines (All other areas).
ATC-25 Appendix B: Lifeline Vulnerability Functions 28.1 Compressor Station 0.30 
Q VI V11 VIII IX X Modified Mercalli Intensity (MMI) Figure B-103 Damage percent by intensity for compressor stations.
on the site. Compressors are typically used designed to yield over a long length to boost pressures in long distance dissipate energy.
transmission lines.
2. Direct Damage Typical Seismic Damage: Damage experienced at the site may include sliding Basis: Damage curves for compressor and toppling of unanchored equipment, stations in the natural-gas system are based stretching of anchor bolts on stacks and on ATC-13 data for FC 10, medium-rise columns, damage to old timber cooling reinforced masonry shear wall buildings; FC towers, and sliding of unrestrained 66, electrical equipment; and FC 68, horizontal tanks on plinths. Piping may mechanical equipment (see Figure B-103).
rupture because of movement of attached Compressor stations are assumed to be a unanchored equipment. Generic building combination of 30% generic buildings, 20% damage ranging from cracking of frames and electrical equipment, and 50% mechanical walls to partial or total collapse may be equipment.
experienced by the control building and other buildings. Standard construction is assumed to represent typical California compressor Seismically Resistant Design: Seismically stations under present conditions (i.e., a resistant design practices include designing composite of older and more modern the buildings and structures in accordance stations). Only minimal regional variation in with the seismic requirements of a local or construction quality of mechanical national building code. In addition, all equipment is assumed.
equipment should be well anchored and equipment on isolators properly snubbed. Present Conditions: In the absence of data Inspection and maintenance of timber on the type of material, age, etc., the cooling towers and piping can mitigate following factors were used to modify the damage. Anchor bolts on stacks should be mean curves for each of the three facility Appendix B: Lifeline Vulnerability Functions ATC-25 Compressor Station R=iE8x b, 1.261 0. 488 B. B3 10 a 0.I803 8.092: a cc 3 -0 'L r R= ax7 Bc 8 DAYS: 3 68 90 120' 158 188 218 248 278 300 330 365 Elapsed Time in Days Figure B-104 Residual capacity for compressor stations (NEHRP California 
classes listed above, under present conditions: restoration curves shown in Figures B-104 through B-106 were derived.
MMI Intensity B.&3DistributionMains Shift NEHRP Mar Area FC 0 FC 66 FC 68 1. General California 7 o 0 0 California 3-6 +1 +1 0 Description: n general, the distribution Non-California 7 +1 +1 0 mains in the natural-gas system are located Puget Sound 5 +1 +1 0 All other areas +2 +1 +1 underground, except where they cross rivers or gorges or where they emerge for connection to compressor or pumping Upgraded Conditions: For areas where it stations. They typically are between 2 and 20 appears cost-effective to improve facilities, inches in diameter and may be composed of assume on a preliminary basis that upgrades steel, cast iron, ductile iron, or plastic result in a beneficial intensity shift of one Approximately 80% of all new distribution unit (i.e., -1), relative to the above present piping is made of plastic. Shut-off valves, conditions. which automatically function when line pressure drops below a certain threshold
Time-to-restoration: Te time-to-pressure, are frequently used restoration data assigned to SF 32c, compressor stations, high-pressure holders, Typical Seismic Damage: The performance and mixer/switching terminals, are assumed of pipelines is, strongly dependent on to apply to all compressor stations in the whether not the supporting soil fails. natural-gas system. By combining these data Routes are often selected along the edges of with the damage curves derived using the river channels to avoid urban buildup and data for C 10, 66, and 68, the time-to-street crossings and to simplify the ATC-25 Appendix B: Lifeline Vulnerability Functions 283 B: Lifeline Vulnerability Functions 283 R=100 Compressor Station 0.38 60 0.50 66 0.20 M1l a b 6 -2.604 0 .709 7 -2.091 0.239 8 
38 68 90 120 150 180 210 240 Z70 300 330 365 Elapsed Time in Days Figure B-1 05 Residual capacity for compressor stations (NEHRP Map Area: California 3-6, Non-California 7, and Puget Sound 5).
Compressor Station R=I100 32c 1.00 10 0.3 Rl l-R IR r IR 66 0.20 M Il a b 6 -2.173 0.289 7 -1.908 0.145 >1 8 -1.724 0.881 C.)
9 -1.592 0.052 Cu 10 -1.5i4 0 .039 0 RR = b 
R-R : I 3. 68 96 1. 18 18I 26 2. 2I DAYS: 30: 560 90 120 150 180 210 240 Z70 300 330 365 Elapsed Time in Days Figure B-1 06 Residual capacity-for compressor stations (All other areas).
B: Lifeline Vulnerability Functions ATC-25 284 Appendix B, Functions ATC-25 Distribution bpk=2 i1 o< 1.0tl to a) E bpk=l2 a 02
to R-S. S m> Other CA7 CA 3-6 __ Non-C bp=0 VI V U111 X X Modified Mercalli Intensity {MMI) Figure B-1 07 Damage percent by intensity for natural gas distribution mains acquisition of real estate. Such routes have to allow lateral and longitudinal slippage high liquefaction potential Pipe damage is Anchors such as thrust blocks or bends most common in soft alluvial soils, at should be excluded within a distance of 300 interfaces between soft and firm soils, at feet of a fault zone and strengthened pipe locations of fault ruptures, or at sharp should be used within the zone. Valve vertical or lateral dislocations or ruptures of spacing near fault zones or in areas of the ground. Pipes may buckle under expected soil failure should be reduced.
compressive forces, especially where they Automatic shut-off valves, which operate cross ruptured faults. Damage may occur as when pressure reduces, should not rely on a result of displacements of unanchored electricity to operate. Proper maintenance compressors or pumps or other above to limit corrosion, which weakens pipes, is ground structures. Several past failures have important for mitigating damage.
been attributed to corrosion combined with surges in line pressure during the 2. Direct Damage earthquake. Rupture of pipes and loss of contents could lead to fire, explosions, or Basis: Damage curves for distribution mains both. in the natural-gas system are based on ATC13 data for FC 31, underground pipelines Seismically Resistant Design: Seismically (see Figure B-107). Standard construction is resistant design provisions for distribution assumed to represent typical California piping are typically minimal. Consequently, distribution mains under present conditions large urban distribution systems should have (i.e., a composite of older and more modern suitable valving installed so that large areas mains). Minimal regional variation in can be broken down into zones. Special construction quality is assumed.
precautions should be taken to reduce earthquake effects at bay, river, and fault Present Conditions: In-the absence of data crossings. Distribution mains at fault on the type of material, diameter, age, etc., crossings should be buried in shallow loose the following factors were used to modify fill or installed above ground near the fault the mean curves, under present conditions: ATC-25 Appendix B: Lifeline Vulnerability
Functions 285 Distribution Hains -3 1.00 31 1.00-I-111 a b 6 -0.038 0.373 -7 -0.038 0.373 8 -0.038 0.280 
n-V -I II II II I I DAYS, : 30 68 90 120 150 1883 210 240 270 308 330 365 Elapsed Time in Days Figure B-1 08 Residual capacity for natural gas distribution mains (NEHRP Map Area: California 3-6, California 7, and Non-California 7).
MM/ B.9 Petroleum Fuels Intensity NEHRP Map Area Shift B. 9.1 Oil Fields California 7 0 California 3-6 0 1. General Non-California 7 0 Puget Sound 5' +1 Description: In general, oil fields in the
All other areas +1 petroleum fuels system may includes Upgraded Conditions: It is not cost-pressure vessels, demineralizers, filters, effective or practical to upgrade existing vertical tanks, horizontal water and oil natural-gas distribution mains, except pumps, large heat exchangers, air perhaps at fault crossings or in areas of compressors, extensive piping, and air-extremely unstable soils. Therefore, no operated valves. Additionally they may intensity shifts for retrofitting are include their own water treatment plant, recommended. which demineralizes and filters water before it is injected as steam into oil wells in the Time-to-restoration: The time-to-area. Control houses with control restoration data assigned to SF 32d, equipment may monitor production and distribution feeder mains, are assumed to flow in and out of the field apply to all distribution mains in the natural-gas system. By combining these data with the Typical Seismic Damage: Building damage curves for FC 31, the time-to-may range from cracks in walls and frames to restoration curves shown in Figures B-108 partial and total collapse. Unanchored or and B-109 were derived. improperly anchored equipment may slide 
*or topple, experiencing damage or causing attached piping and conduit to fail. Well Appendix B: Lifeline Vulnerability Functions ATC-25 Distribution 32d 1, 88 
-.1. 1 I I I I I i I a 11 DAYS: 38 60 90 120 158 IB18 210 248 270 3 338 365 Elapsed lime fin Days Figure B-109 Residual capacity for natural gas distribution mains (Puget Sound 5 and all other areas)'.
casings will move with the surrounding soils is assumed, as shown in the intensity shift and may result in damage to the oil pumps. factors below.
Reduction or increase in production may occur after an earthquake as a result of Present Conditions: In the absence of data geological changes in the oil field. on the type of equipment, age, etc., the following factors were used to modify the Seismically Resistant Design: Buildings mean curve, under present conditions: should be designed in accordance with the seismic provisions of a local or national Mm/ building code. All equipment should be well Intensity anchored. NEHRP Map 2 Area Shift California 7 02. Direct Damage California 3-6 Non-California 7 01 Puget Sound 5 0 Basis: Damage curves for oil fields in the All other areas +1 petroleum fuels system (see Figure B-110) are based on ATC-13 data for FC 68, Upgraded Conditions: For areas where it mechanical equipment. It is believed that appears cost-effective to improve facilities, this facility class best approximates the assume on a preliminary basis that upgrades expected performance of oil fields. result in a beneficial intensity shift of one unit (i.e., -1), relative to the above present
Standard construction is assumed to conditions represent typical California oil fields under present conditions (i.e., a composite of older Time-to-restoration: The time-to-and more modern fields). Only minimal restoration data assigned to SF 1Sa is regional variation in the construction quality assumed to apply to all oil fields. By combining these data with the damage Appendix 3: Lifeline Vulnerability Functions 287
ATC-25 Appendix B: Lifeline Vulnerability Functions 287 Oil Fields _
vi I VII VIII IX X Modified Mercalli Intensity (MMI) Figure B-i 10 Damage percent by intensity oil fields.
curves for FC 68, the time-to-restoration Control rooms house control equipment.
curves shown in Figures B-ill and B-112 Timber cooling towers, refueling stations, were derived. administrative buildings, and wharf loading facilities are also included in some B.9.2 Refineries.
1. General Typical Seismic Damage: A major concern after any earthquake that affects a refinery Description: The typical oil refinery is a fire. Loss of contents from any one of a complex facilitywith many different types of large number of tanks could lead to a fire buildings, structures, and equipment. Tank that could spread throughout the facility storage for the various products produced at Similarly, toxic release and air emissions are the refinery can consist of unanchored also serious concerns. The large cylindrical vertical storage tanks supported on the ground-mounted steel tanks are typically the ground, horizontal pressurized storage tanks most vulnerable components at the refinery supported on steel or concrete plinths, and can suffer tank-wall buckling, bottom spherical tanks supported on legs. rupture, wall-to-bottom weld failure, roof Refineries also include a large number of damage, settlement, or pipe failure. Piping steel stacks or columns anchored to systems can experience flange separations, concrete foundations. Throughout the damage to supports, rupture at connections refinery there are extensive runs of piping, to unanchored equipment, and valve both on the ground and elevated. damage. Mechanical equipment with Mechanical equipment throughout the inadequate anchorage can slide or topple.
refinery includes pumps, heat exchangers, Buildings and structures can experience generic structural damage ranging from furnaces, motors, and generators. Electrical equipment includes transformers, cracks in walls and frames to partial or switchgear, and motor control centers. complete collapse. Control room panels may Appendix B: Lifeline Vulnerability Functions ATC-25 Oil Fields 
30 60 90 126 156 180 210 2401 2Z2 380 338 35 Elapsed Time in Days Figure B-1 11 Residual capacity for oil fields NEHRP Map Area: California 3-6, California 7, Non-California 7, and Puget Sound 5) Oil Fields 
R= 6A. l lI l a lI i DAYS: 38 S 98 126 150 6 10 216 I48 278 308 30 35 Elapsed Time in Days Figure B-1 12 Residual capacity for oil fields (All other areas).
ATC-.25 Appendix B: Lifeline Vulnerability
Functions 2859 Refinery D=100;Y 68 0.30-43 0.48 52 8.30 c)
0 VI ViI VIIl Ix X Modified Mercalli Intensity (MMI) Figure B-1 13 Damage percent by intensity for oil refineries slide or topple, or experience relay implemented. Supports for piping should be problems. Stacks or columns may stretch designed for seismic loads. An emergency anchor bolts. Horizontal tanks may slide on. power system should be provided for control their plinths and rupture attached piping. and emergency equipment as a minimum.
Brick linings in boilers may break.
2. Direct Damage Seismically Resistant Design: Seismically resistant design practices include design of Basis: Damage curves for refineries in the all buildings and structures (including tanks) petroleum fuels system are based on ATC-for seismic requirements in a local or 13 data for FC 43, on-ground liquid storage national code. Storage tanks should be tanks; FC 52, steel chimneys; and FC 68, provided with flexible piping, pressure relief mechanical equipment (see Figure B-113) valves, and well-compacted foundations Refineries are assumed to be a combination resistant to differential settlement. of 40% on-ground storage tanks, 30% Retention dikes with sufficient capacity to chimneys, and 30% mechanical equipment retain all of the oil contained in the enclosed tanks are necessary to mitigate the danger of Standard construction is assumed to catastrophic fire after an earthquake represent typical California refineries under Embankments for such dikes should be present conditions (i.e., a composite of older stable when subjected to ground shaking. and more modern refineries). Only minimal Horizontal tanks on plinths should be regional variation in the construction quality restrained to prevent attached pipes from of mechanical equipment is assumed, as rupturing. Long anchor bolts that are operational loads frequently govern over properly embedded in foundations should seismic requirements be used for heavy equipment and stacks.
Mechanical and electrical equipment should Present Conditions: In the absence of data be anchored to prevent sliding and toppling. on the type of construction, age, etc., the Maintenance and inspection programs for following factors were used to modify the cooling towers and piping should be mean curves for each of the three facility Appendix B: Lifeline Vulnerability Functions ATC-25 Lifeline Vulnerability Functions ATC-25 R=1Bx .5 o
nL O R= gov CU cc AR H-la 43 0.48 52 0.38 II a b 6 EA46 0.7&0 7 X, 443 0.222 B 1.422 8.062 9 101.37B 89. 2 10 0.139 '0.012 R = 
* days + a D-fI., A-tA I I i I I DAYS: 68 90 120 150 1DB 210 241 278 308 330 365 Elapsed Time in Days Figure B-114 Residual capacity for oil refineries (NEHRP California 7).
classes listed above, under present in Figures B-114 through B- 16 were conditions: derived MMI B.9.3 Transmission Pipelines Intensity Shift 1. General NEFHRP Map Area FC 43 FC 52 FC 68 California 7 0 0 0 Description: In general, transmission lines California 3-6 +1 +1 0 in the petroleum fuels system are located Non-California 7 +1 +1 0 underground, except where they cross rivers Puget Sound 5 +1 +1 0 or gorges, or where they emerge for All other areas +2 +2 +1 connection to compressor or pumping Upgraded Conditions: For areas where it stations. They are virtually always welded appears cost-effective to improve facilities, steel and operate at high pressures. Shut-off assume on a preliminary basis that upgrades valves, which automatically function when result in a beneficial intensity shift of one line pressure drops below a certain unit (i.e.), relative to the above present threshold pressure, are frequently included conditions.
Typical Seismic Damage: The performance Time-to-restoration: The time-to-of pipelines is strongly dependent on restoration data assigned to SF lb, whether or not the supporting soil fails.
refineries, are assumed to apply for all Routes are often selected along the edges of refineries in the petroleum fuels system. By river channels to avoid urban buildup and combining these data with the damage street crossings and to simplify the curves derived using the data for FC 43, 52, acquisition of real estate. Such routes have and 68, the time-to-restoration curves shown high liquefaction potentials. Failures in the past have typically occurred at sharp vertical ATC-25 Appendix B: Lifeline Vulnerability Functions 1.00 68 0.30 43 8.40 52 0.30  a b 6 0.446 0.468 7 0.435 0.101 i3 B 0.401 0.835 9 0.234 0.Oi3 10 -0.221 0.009 o R -o3 R b 
R= eV. I I I I I I DAYS: 30 60 90 120 150 180 210 240 270 300 330 365 Elapsed Time in Days Figure B-1 15 Residual capacity for oil refineries (NEHRP Map Area: California 3-6, Non-California 7, and Puget Sound 5).
Refinery R=100x 401. 4 00c 
LO .TU D 8.40 0.30 / g2 Mi a b 6 0.435 0.16 I 7 0.401 0.83, 80.234 0.01: 3
R= I I I I I I I I I I DAYS: 30 68 90 120 150 180 210 240 270 308 330 365 Elapsed Time in Days Figure B-116 Residual capacity for oil refineries (All other areas).
Appendix B: Lifeline Vulnerability Functions -ATC-25 Transmission Pipelines (Petroleum Fuels) H Z -bpk=2 -1S I C)
Modified Mercalli Intensity (MMI) Figure 8-117 Damage percent by intensity for petroleum fuels transmission pipelines.
or lateral dislocations or ruptures of the early 1930s may not. Special precautions ground. Pipes, may buckle under should be taken to reduce earthquake compressive forces, especially where they effects at bay, river, and fault crossings cross ruptured faults. Damage has also Transmission lines at fault crossings should occurred because of axial elongations be buried in shallow loose fill or installed caused by relative movement of two above wound near the fault to allow lateral horizontally adjacent soil layers. Damage and longitudinal slippage. Anchors, such as may occur as the result of displacements of thrust blocks or bends should be excluded unanchored compressors or pumps or other within a distance of 300 feet of a fault zone, above ground structures. Several past and strengthened pipe should be used within failures have been attributed to corrosion the zone. Valve spacing near fault zones or combined with surges in line pressure during in areas of expected soil failure should be the earthquake. Failures of above ground reduced. Automatic shut-off valves should lines have resulted from support failure, not rely on electricity to operate. Proper failure of pipeline attachment to support maintenance to limit corrosion which structure, and relatively large support weakens pipes, is important for mitigating movement. Rupture of pipes and loss of damage.
contents could lead to ignition, fire, and/or explosions. 2. Direct Damage Seismically Resistant Design: Modern high-Basis: Damage curves, for transmission lines pressure petroleum fuel lines provided with in the petroleum fuels, system are based on proper full penetration welds, heavy walls, ATC-13 data for FC 31, underground and strong couplings are very ductile and pipelines (see Figure -117). Transmission have considerable resistance to earthquake pipelines are typically large-diameter welded damage. Welded steel pipeline performance steel pipes that are expected to perform in depends on the integrity of the welds-earthquakes in a manner superior to typical modern butt-welded pipelines perform well, underground pipelines, as indicated by the whereas lines constructed before and during beneficial intensity shift below.
AT, C-25 Appendix B: Lifeline Vulnerability Functions E2 Transmission Pipelines (Petroleum Fuels) I 40_ 4 WI 11 4 Rn 1.UU X E.
Mui a b 7 8.144 e .195 8 0.144 0 195 . 9 e.116 8. 106 10 e.124 e.116 R-SOY R = b 
D-I I I I I I II
DAYS: I I I I I I DAYS: 30 6 98 128 150 1 210, 240 270 30 330 365 Elapsed Time in Days Figure B-118 Residual capacity for petroleum fuels transmission pipelines (NEHRP Map Area: California 3-6, California 7, Non-California 7, Puget Sound 5, and all other areas).
Standard construction is assumed to intensity shifts for retrofitting are represent typical California petroleum fuels recommended.
transmission lines under present conditions (i.e., a composite of older and more modern Time-to-restoration: The time-to-transmission lines). Only minimal regional restoration data assigned to SF 18c, variation in the construction quality is transmission pipelines, are assumed to apply assumed. to all transmission pipelines in the petroleum fuels system. By combining these Present Conditions: In the absence of data with the damage curves for FC 31, the on the type of material, diameter, age, etc., time-to-restoration curves shown in Figure the following factors were used to modify B-i 18 were derived.
the mean curves, under present conditions: B.9.4 Distribution Storage Tanks MM/ Intensity 1. General
NEHRP Map Area Shift California 7 -1 Description: Most oil storage tanks are California 3-6 -1 unanchored, cylindrical tanks supported Non-California 7 -1 Puget Sound 5 -1 directly on the ground. Older tanks have All other areas -1 both fixed and floating roofs, while more modern tanks are almost exclusively Upgraded Conditions: It is not cost-floating-roofed. Diameters range from effective or practical to upgrade existing approximately 40 feet to more than 250 feet.
petroleum fuels transmission pipelines, Tank height is nearly always less than the except perhaps at fault crossings or in areas diameter. Construction materials include of extremely unstable soils. Therefore, no welded, bolted, or riveted steel. Tank Appendix B: Lifeline Vulnerability Functions ATC-25 foundations may consist of sand or gravel, or a concrete ring wall supporting the shell.
Typical Seismic Damage: On-ground oil storage tanks are subject to a variety of damage mechanisms, including: (1) failure of weld between base plate and wall, (2) buckling of tank wall (elephant foot), (3) rupture of attached rigid piping because of sliding or rocking of tank, (4) implosion of tank resulting from rapid loss of contents and negative internal pressure, (5) differential settlement, (6) anchorage failure or tearing of tank wall, (7) failure of roof-to-shell connection or damage to roof seals for floating roofs (and loss of oil), (8) failure of shell at bolts or rivets because of tensile hoop stresses, and (9) total collapse.
Torsional rotations of floating roofs may damage attachments such as guides, ladders, etc.
Seismically Resistant Design: Seismically resistant design practices for ground oil distribution storage tanks include the use of flexible piping, pressure relief valves, and well-compacted foundations and concrete ring walls that prevent differential settlement. Adequate freeboard to prevent sloshing against the roof should be maintained. Positive attachment between the roof and shell should be provided for fix roofed tanks.
The bottom plate and its connection to the shell should be stiffened to resist uplift forces, and the base plate should be protected against corrosion.
Abrupt changes in thickness between adjacent courses should be avoided.
Properly detailed ductile anchor bolts may be feasible on smaller steel tanks.
Maintaining a height-to-diameter ratio of between 0.3 and 0.7 for tanks supported on the ground controls seismic loading.
Retention dikes are needed to retain spilled oil and prevent it from reaching ignition sources. These dikes should have sufficient capacity to retain all oil that could spill within their confines. Also, all retention dike embankments should be stable in ground shaking.
2. Direct Damage Basis: Damage curves for distribution storage tanks in the petroleum fuels system are based on ATO-13 data for FC 43, on-ground liquid storage tanks (see Figure B119).
Standard construction is assumed to represent typical California distribution storage tanks under present conditions (i.e., a composite of older, non-seismically designed tanks as well as more modern tanks designed to seismic requirements (e.g., API 650).
Present Conditions: In the absence of data on the type of material, age, etc., the following factors were used to modify the 
mean curves, under present conditions: MMI Intensity NEHRP Map Area Shift California 7 0 California 3-6 +1 Non-California 7 +1 Puget Sound 5 +1 All other areas +2 Upgraded Conditions: For areas where it appears cost-effective to improve facilities, assume on a preliminary basis that upgrades result in one or two beneficial intensity shifts (i.e., -1 or -2), relative to the above present conditions.
Time-to-restoration: The time-to-restoration data assigned to SF 18d, distribution storage tanks, are assumed to apply to all tanks. By combining these data with the damage curves for FC 43, the time-to-restoration curves shown in Figures B120 through B-121 were derived.
B.10 Emergency Service B.10.1Health Care 1. General Description: Health care facilities (hospitals) are typically housed in one or more buildings. Construction type varies significantly. Smaller hospitals may contain only limited equipment associated with building services. Large hospitals may contain water treatment equipment, emergency power diesels, chillers, and boilers, as well as sophisticated equipment used for treating patients.
ATC-25, Appendix B: Lifeline Vulnerability Functions Distribution Storage Tanks : D=11.' lid 1.00 a) Eo D=50z Other CA 36 Non CA 7 0 I X
VII Vi1 IX
I Modified Mercalli Intensity (MMI) Figure B-1 19 Damage percent by intensity for petroleum fuels distribution storage tanks.
Distribution Storage tanks
6 0.408 0.110
7 0.403 0.891 8 0.3U30 H.041 .
9 8.352 0.020 10 0.258 0.009 ;a .2 Fi R b 
* days + a n 1) D-A .
l-A. I I I I I I I I I DAYS: 30 60 90 120 150 1 210 248 Z70 300 330 365 Elapsed Time in Days Figure B-i 20 Residual capacity for petroleum fuels distribution storage tanks (NEHRP California 7).
296-296 Appendix B: Lifeline Vulnerability Functions ATC-25 > distribution Storage Tanks 4a lt Af 1 O1
6 0.403 0.091 7 0113 :80 0.841 .6, 8 352 0.828 9 0.258 8.889 C1
Ca 10 8.142 0.006 -0 R= E0x R = 
Rz 07 I I i I I DAYS: 3D 68 so 128 158 188 218; Z48 278 388 33 35 Elapsed Time in Days Figure B-1 21 Residual capacity for petroleum fuel distribution storage tanks (NEHRP Map Area: California 3-6, Non-California 7, and Puget Sound 5).
Distribution Storage tanks 5=1808 1.88 43 1.0 ml ab 6 8.388 8.841 7 0.828 'U O.258 809 a 98.142 8. BO a 1 80.860 .00, 0 R= 96c R b 
* days + a /2 . ) CE R rv I I I
DAYS: 38 G 9B 128 158 188 218 24 278 3881 330 35 Elapsed Time in Days Figure B-1 22 Residual capacity for petroleum fuels distribution storage tanks (All other areas).
ATC-25 Appendix B: Lifeline Vulnerability Functions Health Care D=A08V 10 80 o
0 UI VII VIII Ix X Modified Mercalli Intensity (MMI) Figure B-123 Damage percent by intensity for health care facilities.
Typical Seismic Damage: Buildings may design. However, equipment and experience generic building damage ranging nonstructural items also require special from cracks in walls and frames to partial attention if the hospital is to remain and total collapse. Unanchored or functional. All critical equipment should be improperly anchored equipment may slide anchored. Equipment on isolators should be or topple. Equipment supported on isolation snubbed. The emergency power system mounts with no snubbers may fall off the should be closely scrutinized, and the mounts and rupture attached piping and emergency diesel-generator system should conduits. Unrestrained batteries on racks be maintained and tested frequently.
may fall, rendering the emergency power Equipment used to treat patients should be systems inoperable. Suspended ceilings may stored and restrained properly. Medicine in fall and impede operations. Equipment cabinets should be stored in a manner that necessary for treating patients maybe prevents it from falling to the floor.
damaged, especially if it is supported on carts or on wheels, or is top-heavy. 2. Direct Damage Equipment that requires precise alignment is also susceptible to damage. In garages, Basis: Damage curves for health care structural damage may result in ambulances facilities are based on ATC-13 data for FC being unavailable when they are needed. 10, medium-rise reinforced masonry shear wall buildings (see Figure B-123). FC 10 was Seismically Resistant Design: As essential chosen to represent a generic building, facilities, hospital should be designed to based on review of damage curves for all remain operational in the event of a major buildings.
earthquake. Typically this involves using larger design forces and meeting more Standard construction is assumed to restrictive design requirements than those represent typical California health care required by building codes for the building facilities under present conditions (i.e., a 
Appendix B: Lifeline Vulnerability Functions ATC-25 B: Lifeline Vulnerability Functions ATC-25 Health Care 4 Dt-R=1010x I.0J a b 8.1?10. ii O. O25 0.Hi4 3 -0.801 8.8e7 -El.878 EMs C) R= SOz -iC 1):5 
* days+ a C a R= l l i l DAYS: 38 60 98 126 150 180 218 240 27 3 330 365 Elapsed Time in Days Figure B-124 Residual capacity for health care facilities (NEHRP California 7).
composite of older and more modern health Time-to-restoration: The time-to-care). It is assumed that such facilities were restoration data assigned to SF 8, health designed using enhanced seismic care services, are assumed to apply to all requirements and that the beneficial health care facilities. By combining these intensity shifts, indicated below are data with the damage curves for FC 10, the appropriate. time-to-restoration curves shown in Figures B-124 through B-126 were derived.
Present Conditions: In the absence of data on the type of construction, age, etc., the B. 0.2 Emergency Response Services following factors were used to modify the mean curves, under present conditions: 1. General Mm/ Description: Emergency response services Intensity include fire and police stations. Both fire NEHRP Map Area Shift and police stations may be housed in low- to California 7 -1 medium-rise structures of virtually any type California 3-6 0 of construction. In many urban areas these Non-California 7 0 Puget Sound 5 0 structures are old and were built prior to the All other areas adoption of earthquake design codes.
Firehouses typically include garages to Upgraded Conditions: For areas, where it house engines, sleeping quarters, kitchens, appears cost-effective to improve facilities, utility rooms, and communications rooms.
assume on a preliminary basis that upgrades Some stations have hose towers used to dry result in one or two beneficial intensity hoses after use. Police stations typically shifts (i.e., -1 or -2), relative to the above include a dispatch center, detention area, present conditions. and squad room.
ATC-25 Appendix B: Lifeline Vulnerability Functions Health Care R=100v MrII a b 76 0.171 0.025 7 0.116 0.014 8 -0.001 0. 00? 9 -0.878 0.005
10 -0.165 0.004 C) R= 5e R = b 
* days a -o
DAYS. 30 6e 98 120 10 180 210 Z40 270 300 330 365
, Elapsed Time in Days Figure B-1 25 1Residual capacity for health care facilities (NEHRP Map Area: California 3-6, Non-California 7, and Puget Sound 
W I I I I .I I I I i DAYS: 30 60 98 128 158 180 210 240 278 308 330 365 Elapsed Time in Days Figure B-i 26 Residual capacity for health care facilities (All other areas).
300 Appendix B: Lifeline Vulnerability Functions ATC-25 Emergency Response Service C5 0) VIWI VIII Ix x Modified Mercalli Intensity (MM]) Figure B-127 Damage percent by intensity for emergency response service facilities.
Typical Seismic Damage: Buildings housing separate hose towers should be provided).
fire and police stations may experience Communications equipment should be generic building damage ranging from properly restrained and provided with cracking of frames and walls to partial or backup emergency power. All equipment, total collapse. Fire stations may be more especially boilers, should be well anchored.
susceptible to damage than most buildings Engines and patrol cars should be stored in because of the presence of the large garage areas that are expected to escape serious door openings and the hose towers, which damage.
interrupt the continuity of the roof diaphragm and frequently have 2. Direct Damage discontinuous shear walls or frames.
Significant damage to a fire station could Basis: Damage curves for emergency lead to loss of use of engines housed within response service are based on ATC-13 data them anchored communications for FC 10, medium-rise reinforced masonry equipment in both stations could severely shear wall buildings (see Figure B-127). FC hinder operations immediately after an 10 was chosen to represent a generic earthquake building, based on review of damage curves for all buildings. Although more modern Seismically Resistant Design: Both fire and facilities may be designed to enhanced police stations are critical buildings that seismic design criteria, many old police and should remain operational after a major fire stations are still in use. Consequently, earthquake. Accordingly, these facilities no intensity shifts from typical FC 10 should be designed to meet the seismic performance are assumed.
requirements for critical buildings of a national or local building code. Geometric Standard construction is assumed to irregularities that will result in poor seismic represent typical emergency response performance should be avoided (e.g., facilities under present conditions (Le., a ATC-25 Appendix B: Lifeline Vulnerability Functions3 30 Emergency Response Service R=1O0Y a) m =e DAYS: 3 68 90 128 150 180 210 248 270 3 338 365 I Elapsed Time in Days Figure B-128 Residual capacity for emergency response service facilities (NEHRP California 7) composite of older and more modern police Upgraded Conditions: For areas where it and fire stations). appears cost-effective to improve facilities, assume on a preliminary basis that upgrades Present Conditions: In the absence of data result in one or two beneficial intensity on the type of construction, age, etc., the shifts (i.e., -1 or -2), relative to the above following factors were used to modify the present conditions.
mean curves, under present conditions: Time-to-restoration: The time-to-MM/ restoration data assigned to SF 23, Intensity emergency response services, are assumed NEHRP Map Area Shift to apply to all emergency response service California 7 0, facilities. By combining these data with the California 3-6 +1 damage curves for FC 10, the time-to-Non-California 7 +1 Puget Sound 5 +1 restoration curves shown in Figures B-128 through B-130 were derived.
All other areas +2 Appendix B: Lifeline Vulnerability Functions ATC-25 Emergency Response Service "Ml a b 6 -.1B5 O. O854 7 -0.84 0, .022 8 -1, 023 8.214 -5 9 -8.B B 8. 1009
0 10 8.815 0.887 CO:3 R = b, 
* days +-a .0 R= OM: 30 68 98 128 1S 188 218 248 278 3 33 35 Elapsed Time in Days Figure B-1 29 Residual capacity for emergency response service facilities (NEHRP Map Area: California 3-6, Non-California 7, and Puget Sound 5).Emergency Response Service R=I8% 1.00 10 1.00. 3 n I a b, 6 -0.048 8 .822 7 -8823 0, i84 B 
* days + a :3 :0 R= I 1 I I i I DAYS: 38 68 98 128 158 188 218 248 278 3081 33 35 Elapsed Time in Days Figure B-130 Residual capacity for emergency response service facilities (All other areas).
ATCC-25 Appendix B: Lifeline Vulnerability Functions