FEDERAL EMERGENCY MANAGEMENT AGENCY 

Inventory of Lifelines in the CajonPass, California

Issued in Furtherance of the Decade

for Natural Disaster Reduction

Earthquake Hazard Reduction Series 60

FEMA 225 1 February 1932:

Rv. . .\ I I / Y
Inventory of Lifelines in the Cajon

Pass, California

Submitted to the Federal Emergency Management Agency

Washington, D.C.

Submitted by:

INTECH Inc.

11316 Rouen Dr.

Potomac, MD 20854-3126

Submitted August 1991

Co-Principal Investigators:

Dr. Phillip A. Lowe, INTEC, Inc.

Dr. Charles F. Scheffey, INTEC, Inc.

Mr. Po Lam, Earth Mechanics, Inc.
INVENTORY OF LIFELINES IN THE CAJON PASS, CALIFORNIA

TABLE OF CONTENTS

ITEM

List of Figures ......................

List of Tables .... . ......

INTRODUCTION ANDBACKGROUND. ...................

BACKGROUND .............. ......

PURPOSE, GOALS, AND STUDY APPROACH . .......................

BIBLIOGRAPHY FOR SECTION 1.0 ..............................

EXECUTIVE SUMMARY ................................................

SULbARY ................... ..

BIBLIOGRAPHY FOR SECTION 2.0 ....................

PAGE

4

4

8

3.0 SITE CONDITIONS AND LIFELINES .................................

3.1 SITE CONDITIONS .............................................

3.1.1 Fault Information and Ground Rupture (Displacement) Potential

3.1.2 Soil and Bedrock Conditions ..................................

3.1.3 Seismic Events .............................................

3.1.4 Ground Shaking Hazards .........................................

3.1.5 Topographic and Ground Relief Features and Landslide Hazards .

3.1.6 Hydraulic, Groundwater Conditions, and Liquefaction Potential .

3.1.7 Bibliography For Section 3.1 .................................

3.2 COMMUNICATION LIFELINES ..................................

3.2.1 Fiber Optic Cables ...............................

3.2.2 Microwave and Radio Towers ............................

3.2.3 Bibliography For Section 3.2 .......................

3.3 ELECTRICAL POWER LIFELINES ..........................

3.3.1 Los Angeles Department of Water & Power Facilities

3.3.2 Southern California Edison Company Facilities .....

3.3.3 Bibliography For Section 3.3 ......................

3.4

3.4.1

3.4.2

3.4.3

3.5

3.5.1

3.5.2

3.5.3

FUEL TRANSPORTATION LIFELINES ......................

Natural Gas Pipelines .............................

Liquid Fuel Pipelines .............................

Bibliography For Section 3.4 ......................

TRANSPORTATION LIFELINES .............

Highways ..........................................

Railways ........................ .............

Bibliography For Section 3 .5 .....................

440 CONTACTS MADE DURING THE STUDY .....................................

Appendix A Details for Figure 3.1-7, Earthquake Faults

8

9

14

16

17

18

21

27

30

32

37

39

39

39

43

46

46

48

53

56

56

56

64

69

69

71

i

2.0

2.1

2.1

............

.............A........

.......... . .

............

................. +

*. . . I.....

.. S.. +.......

............

............

............
LIST OF FIGURES

FIGURE PAGE

1-1 Map of the Cajon Pass Area ...................................... 3

2-1 Composite Map of Lifelines in the Cajon Pass Study Area ... ...... 6

3.1-1 Regional Fault Map ............................................ 10

3.1-2 Active Fault Locations in the Study Area ...................... 11

3.1-3 Cajon Pass Region Geologic Units With High Water Table

Identified ................................................... 15

3.1-4 Observed Landslides Within the Study Area .................... 19

3.1-5 Rebuilt Power Transmission Towers on a Landslide Scar ... ...... 20

3.1-6 Landslide Scar in Lone Pine Canyon Along the San Andreas

Fault Zone .................................................................... 20

3.1-7 Location of Shallow Water Table Conditions ..................... 23

3.2-1 Map of the Communication Lifelines ............................ 31

3.2-2 Looking North on Old Highway 66 (Cajon Canyon Road)............. 32

3.2-3 Fiber Optic Conduits Crossing a Cajon Canyon Road Bridge ......34

3.2-4 Details of the Fiber Optic Conduits and Hangers on a Cajon

Canyon Road Bridge ............................................ 34

3.2-5 Crib Wall Retaining the Southbound Lanes of I-15 With Fiber

Optic Conduits Buried at the Wall Toe ......................... 35

3.2-6 Details of Fiber Optic Conduit Supports on the Concrete

Culvert Wall .................................................. 35

3.2-7 Fiber Optic Conduits Heading Under I-15 Attached to a

Concrete Culvert Wall ......................................... 36

3.2-8 A Fiber Optic Conduit Hung From A Bridge With A Water

Distribution Pipe Directly Above It ........................... 38

3.3-1 Map of the Electric Power Lifelines .......... w................ 40

3.3-2 A View of Power Lines & Buried Fuel Pipelines Crossing the

San Andreas Fault Zone ......... ............................... 41

3.3-3 Power Towers at the Edge of a Steep Ravine Near the San

Andreas Fault Zone ............................................ 42

3.3-4 Lugo Substation Control Facilities & Equipment .... ............ 44

3.3-5 Lugo Substation Circuit Breakers .............................. 44

3.3-6 Typical Electric Transmission Tower Footings .................. 45

3.4-1 Map of the Fuel Pipeline Lifelines ............................ 47

3.4-2 Natural Gas Pipeline Crossing Under Two Railroads ... .......... 49

3.4-3 An Exposed Section of The Natural Gas Pipeline ................ 50

3.4-4 Details of the Ground Support For Exposed Sections of

Natural Gas Pipelines ......................................... 51

3.4-5 Natural Gas Pipeline Valve Station on Baldy Mesa Rd. ... ....... 52

3.4-6 The Natural Gas Pipeline Crossing the California Aqueduct ..... 52

3.4-7 The Petroleum Products Pipeline Valve Station on the Shoulder

of Baldy Mesa Rd. ............................................. 54

ii
LIST OF FIGURES (Continued)

FIGURE PAGE

3.4-8 Petroleum Products Pipelines Hung Under the Baldy Mesa Rd.

Bridge Over the California Aqueduct ........................... 55

3.5-1 Map of the Transportation Lifelines ............................ 57

3.5-2 I-15 Bridge Over Lytle Creek Wash ............................. 59

3.5-3 I-15 Bridge Over Cajon Creek Wash ........................... 59,

3.5-4 I-15 Bridge Over Kenwood Avenue ............................ 60

3.5-5 I-15 Arch Bridge Over Matthews Road . 61

3.5-6 1-15 Box Bridge Over the Railroad ............................... 62

3.5-7 I-15 & Access Road Bridges Over the Railroad .. 62

3.5-8 Highway 138 Cut & Fill at Cajon Junction . 63

3.5-9 Railroad Bridges in Cajon Wash, I-15 Bridge in Background .65

3.5-10 Concrete Beam Railroad Bridge in Cajon Creek Near Cajon

Junction ............ .... . 66

3.5-11 Rubble Pier Railroad Bridge in Cajon Creek Near Cajon Junction. 67

3.5-12 Ballasted Deck Railroad Bridge Over Highway 138 . 67

3.5-13 Highway 138 Bridge Over Railroad at Cajon Junction ............ 67

3.5-14 Railroad Tunnel North of Cajon Junction ....................... 63

3.5-15 Typical Short Span Railroad Bridges North of Cajon Junction ... 68

LIST OF TABLES

TABLE PAGE

3.1-1 Depth to Ground Water Measured From Wells ..................... 24

iii
INVENTORY OF LIFELINES IN THE CAJON PASS, CALIFORNIA

1.0 INTRODUCTION AND BACKGROUND

1.1 BACKGROUND

Lifelines (e.g., communication, electric power, liquid fuels, natural gas,

transportation, water and sewer systems, etc.) are presently being sited

in "utility or transportation corridors" to reduce their right-of-way

environmental, aesthetic, and cost impacts on the community and on land

use. The individual lifelines are usually constructed or modified at

different time periods, resulting in their being built to different

standards and in different siting criteria being applied to different

segments of an individual lifeline or to different lifelines that provide

similar functions. Presently, the siting review usually does not consider

the impact of the proximity or collocation of one lifeline upon the risk

to or vulnerability of other lifelines from natural or manmade hazards or

disasters, either because the other lifelines have not yet been installed

or because such a consideration has not been identified as a factor in the

siting evaluation.

In August 1988, a train derailment in northern California also damaged a

petroleum pipeline which was buried along the railroad right-of-way. The

result was a spill of the pipeline fluids in addition to the derailment

(but no significant loss of property and no injuries to or

casualties), 1 . The State of California Office of the Fire Marshall

became involved as it is the California agent responsible for the

inspection and enforcement of safety criteria for pipelines that transport

liquids. When another derailment in San Bernardino occurred in May l989cl

2), which resulted in severe property damage and the loss of life, the

Office of the Fire Marshall also responded to see if the derailment had

impacted a petroleum products pipeline that was buried along the railroad

right-of-way. It was decided that the pipeline was not damaged, and the

fire and safety personnel turned over the site to the railroad to allow

them to clean up the site. About a week later the pipeline ruptured and

the resulting fire caused considerable property damage and loss of life.

The subsequent investigations12) concluded that the pipeline may have been

damaged during the derailment, but that the most probable cause of its

damage was the derailment clean up operations.

In a similar sense, communication lines along a highway bridge would be

vulnerable to failure if the bridge were to displace or fail during a

disaster event. In fact, frequently highway bridges and overpasses are

used to route other lifelines, such as communications and pipelines, over

causeways and water bodies. Such lifelines can be damaged by failure of

the superstructure, bridge foundation movement, or ground deformation

1 Numbers in parentheses refer to the bibliography found at the end of

each major report section.

1
along the approaches to the bridge. Settlement and lateral displacement

adjacent to abutments have been especially troublesome because such

movements tend to impose deformations on the lifelines where they are

locally constrained at the attachment or penetration of the abutment.

There are many such examples of lifeline interdependency that occurred

during the 1989 Loma Prieta earthquake. For example'(1-3

' 4), the lack of

fire fighting water in the Marina district resulted from pipeline

failures. Failed water pipelines have caused ground erosion that has

failed the foundations of other lifelines. Loss of electric power

prevented the fire department from closing remote, electrically-controlled

valves that were intended to isolate damaged portions of the water

lifeline system. This resulted in the loss of the use of storage

reservoirs and the ability to provide critically needed, fire fighting

water. Electrical failures and shorts have ignited leaks from fuel

pipelines, increasing the level of damage associated with the failed flue

delivery lifeline.

In response to these types of situations, the Federal Emergency Management

Agency (FEMA) is focusing attention on the use of such corridors, and they

initiated this study to examine the impacts of siting multiple lifeline

systems in confined and at-risk areas.

1.2 PURPOSE, GOALS, AND STUDY APPROACH

The overall FEMA project goals are to develop, for multiple lifeline

systems in confined and at-risk areas, a managerial tool that can be used

to increase the understanding of the lifeline systems' vulnerabilities and

to help identify potential mitigation approaches that could be used to

reduce those vulnerabilities. The goals also are to identify methods to

enhance the transfer of the resulting information to lifeline system

providers, designers, builders, managers, operators, users, and

regulators.

To provide a specific example of how the managerial tool can be used, it

was decided that the methods should be applied to the lifelines in the

Cajon Pass, California, for an assumed earthquake event at the Pass.

The purpose of this report is to provide an inventory of the major

lifeline systems in the Cajon Pass and the earthquake and geologic

analysis tools available to identify and define the level of seismic risk

to those lifelines. The information in this report can then become a

validated data base for use in the development of the required analysis

methodology for evaluating the impact of proximity or collocation of

lifelines on the vulnerability of nearby lifelines.

Figure 1-1 is a reproduction of a highway map (courtesy of the Automobile

Club of Southern California) of the San Bernardino, California, area

(1:250,000-scale). The locations of the Cajon Pass study area and the May

12, 1989, train derailment and the subsequent May 25, 1989, petroleum

products pipeline rupture are identified on the map.

2
Figure 1-1, Map of the Cajoni Pass Area

L ~ ~~ ~

MUS~~ ~ ~ ~ ~ ~ ~ ~ M

wi iML' ,'11 -

~~~~~~~~-~ ~ ~ ~ ~ -

-- ~~~~~ ~~~ -AU MBI 4- OFSOUTHERN CALIFORNIA _

a DY~~~~~~~~~~~~~~~~~~t

CUCAMONGA __-fBERNA I O0 ' - -~~---- 1-f4UTANPEEIAL - . -'-

MON__ -~~~~~~~~~~~~~~~~~~~~~~~ - - ~~~~~~~~~~~~~~~~ -=0P 

PC-RVERSDE ~i-I¶R~

~INORCI 

7-1 HILLS~~~~~~~~LUE~A1UA

~~J' - A~~~uh~~Th~ ~ a~~aaa'~~~ SUNTh~~~~E-X

OE GARDR U. 

3
The methodology used in developing the information for this report is as

follows. Site reconnaissance surveys of the Cajon Pass were made to

familiarize the researchers with the specific site conditions and to

identify areas of special interest. Contacts were then made with each

lifeline system owner and the study information needs were explained. The

owners responded with engineering data on their specific system(s).

Contact also was made with the regulatory agencies as well as with

appropriate emergency planners. Those direct contacts provided basic data

on each lifeline system, and they provided validation of the data (or in

some cases raised questions as to our understanding of the data).

Additional site visits were then made to confirm and further validate the

available data. This report was then prepared, with heavy reliance on the

validated data or on the data provided by each lifeline owner. As a final

validation of the work, the draft report was submitted to each

organization that provided information for the report with the request

that it review the material to assure that the information provided was

not misunderstood or to provide additional clarification data when

appropriate.

Section 2.0 of this report presents an executive summary of the study. It

also adds a discussion in which all of the separate data are combined onto

a single map to identify the regions of greatest congestion. Section 3.0

presents the specific data for the lifeline systems and the seismic data

and codes available to determine the earthquake impact on those lifelines.

Section 4.0 presents a list of the organizations contacted during this

study.

1.3 BIBLIOGRAPHY FOR SECTION 1.0

1-1 Source of information: conversations with the State of California

Office of the Fire Marshall, Office of Pipeline Safety.

1-2 National Transportation Safety Board Railroad Accident Report

NTBS/RAR-90/02 (PB90-916302), June 19, 1990.

1-3 T.D. O'Rourke, et. al., "Geotechnical and Lifeline Aspects of the

October 17, 1989, Loma Prieta Earthquake in San Francisco", Technical

Report NCEER-90-0001, National Center for Earthquake Engineering

Research, January 1990.

1-4 T.D. O'Rourke, et al., "Response of the San Francisco Water Supply

System During the 1989 Loma Prieta Earthquake", presented at the

conference Putting the Pieces Together, San Francisco, CA, October

1990.

2.0 EXECUTIVE SUMMARY

2.1 SUMMARY

This report is the first phase of a study commissioned by the Federal

Emergency Management Agency (FEMA) to evaluate the vulnerabilities

occurring from the siting of multiple lifeline systems in confined and at4
risk areas due to their interactions from natural and manmade disasters.

The goals of the overall study are to identify the lifeline systems'

vulnerabilities, to identify potential mitigation approaches that could be

used to reduce those vulnerabilities, and to identify methods to enhance

the transfer of the resulting information to lifeline system providers,

designers, builders! managers, operators, users, and regulators.

The purpose of this report is to provide an inventory of the major

lifeline systems in the Cajon Pass and the earthquake and geologic

analysis tools available to identify and define the level of seismic risk

to those lifelines. The Cajon Pass and an earthquake event will be used

as a suitable test case for applying the evaluation methodology which will

be developed as a part of the overall study. However, the overall program

goal is to provide a methodology that can be readily applied to other

regions and locations in the United States and that is adaptable to

disaster conditions in addition to earthquakes. The information in this

report can be used as a validated data base for use in the development of

the required analysis methodology for evaluating the impact of proximity

or collocation of lifelines on the vulnerability of nearby lifelines.

Figure 1-1 also shows that the Cajon Pass is a natural topographical

opening between the San Bernardino and the San Gabriel mountain ranges.

As such, it has been used for years as the major route for lifelines

between the Los Angeles coastal plain and the high desert regions. Within

the Pass the following lifeline systems (see Figure 2-11 it is provided in

full-size in Volume 2 of this report) shows the lifelines that have been

examined for the current study:

Communication Lifelines -- fiber optic cables, radio, cellular

telephone, and microwave towers;

Electrical Lifelines -- high voltage transmission systems, a

hydroelectric generation station, and a transmission system electric

power substation;

Fuel Pipeline Lifelines -- natural gas transmission and petroleum

products pipelines;

Transportation Lifelines -- interstate highways, state highways,

bridges associated with the highways, passenger and freight railroad

lines, and the bridges and tunnels associated with the railroad

lines.

Although Figure 2-1 shows that the lifeline routes are often focused in a

narrow band, the topology of the region is not the only reason for that as

the Pass is generally several miles wide (it is about 1/2 mile wide at its

narrowest at Blue Cut) and many of the lifeline routes could have been

placed on the slopes of the mountains that form the edges of the Pass.

There are large subregions in which there are only one or no lifelines in

the overall study region. However, most of the lifeline systems are

located near or in the foot of the Pass itself. This is the congested

lifeline area. The figure shows a major focusing of the rail,

5
117 21

'a *I.a

-. -. a ;~'.---'0 

;-3 I . , I I, '. .i . j ' `-a .I I , ',_ ' .a

IIT 1 so0' 11b'S ar

Figure 2-1 Composite Map of Lifelines In the Cajon Pass Study Areas

SCALE

0 2 , , XW

EXPLANATION

- I-LB 

MUa

- £-P ---

------- -p ---- -p -

_______ .? I_____, 

... I ...__I 

-4...__...__-

l' COMNe. ZMATMW Di VW?

COanTUs VMVAL MmeaFOT

SNTOWTZ

PFAD XAWWLT

,mws

rLUME-PEN5TOCX

rmin AD

NATRL uam ruam

no aYr CAMn

LargerScale Figure

Located at

Endof Document

6
highway, communication, and fuel pipelines in the southern part of the

Pass near the community of Devore, another congested area involving all of

the lifeline systems near Blue Cut (which is also traversed by the San

Andreas fault zone), and another congested area near and north of Cajon

Junction. Above the summit of the Pass (in the high desert area), the

lifeline systems spread out, although the communications and fuel pipeline

lifelines remain collocated in that region.

In studying the Cajon Pass area, it has become apparent that the

objectives considered in siting the lifelines were weighted heavily

towards minimizing the lifelines' immediate impact on the aesthetics and

the surface environment of the area and on the costs associated with

acquiring the rights-of-way and installing of the lifelines. In a number

of instances, the siting route was a response to Federally-imposed routing

criteria. Thus, in may parts of the study area the lifelines are in

parallel or coincident paths, thereby reducing the amount of land

disturbed by their construction and the costs for acquiring the required

rights-of ways. Very limited, documented analyses or considerations of

the impact of the failure of one lifeline upon the operation and

reliability of another lifeline were found during the current study. Part

of the reason for this appears to be that a number of different agencies

and offices are responsible for the siting design and approval for the

individual lifelines. Each such authority does not have direct

responsibility or authority for the evaluation of the other facilities in

close proximity to the lifeline for which they are responsible. It is

believed that this siting approach is representative of most lifeline

siting situations within the United States, although that question has not

been examined during this study.

Chapter 3.0, of this report provides more detailed maps. Figures 3.2-1,

3.3-1, 3.4-1, and 3.5-1 (for the communications, electrical, fuel

pipeline, and transportation lifelines, respectively) show the routes of

the separate lifeline systems. Figures 3.1-2, 3.1-3, 3.1-4, and 3.1-7

(for the earthquake fault zones, geologic conditions, landslide areas, and

water table (e.g. potential soil liquefaction zones)) show the regions

where seismic conditions could induce forces and stresses on the

individual lifelines. All of these items must be examined together to

obtain a realistic estimate of the probable failure conditions exerted on

individual lifelines.

In the subsequent analysis of the potential hazards to and vulnerabilities

of the lifeline systems from earthquakes (to be reported in a following

report "Collocation Impacts on the Vulnerability of Lifelines During

Earthquakes With Application to the Cajon Pass, California") it will be

necessary to relate the composite of lifeline locations with geologic

areas subject to landslides. and liquefaction as well as to identify their

physical relationship to the contours of equal earthquake shaking

intensity. A part of that study will be to select and justify the

appropriate earthquake event to be analyzed. As discussed in Section 3.1,

the earthquake fault locations. are well mapped and are available for use

in the current study. The soil and bedrock conditions can be based on the

United States Geological Survey (USGS) data(2-1). That information will

7
provide input to the QUAK2NW3 earthquake shaking intensity model developed

at the USGS 22). Landslide potential can be determined by applying the

USGS models(23 ,

2 4 ) with the results supplemented by the data of Figure 3.1-

5. Liquefaction potential can be determined by applying the USGS

methodology(25 ) with the results supplemented by the data of Figure 3.1-8.

Thus, there are sufficient data and models available to allow the

calculation of the earthquake and geologic impacts on the lifeline

systems.

The study presented in this report was prepared by obtaining data from the

lifeline system owners and regulators and by conducting numerous on-site

examinations. The data were further validated by having the draft report

reviewed by those who supplied the input data to assure that they were not

misunderstood and that they were complete. As such, the information can

be considered as a reliable data base upon which the rest of the FEMAsponsored study can be built. Chapter 3.0 presents the results obtained,

Chapter 4.0 identifies the organizations and offices contacted during the

study.

2.2 BIBLIOGRAPHY FOR SECTION 2.0

2-1 J. Davis, et. al., "Earthquake Planning Scenario for a Magnitude 8.3

Earthquake in the San Andreas Fault in Southern California",

California Division of Mines and Geology, Special Publication 60,

1982.

2-2 J. Evernden, et. al., "Seismic Intensities of Earthquakes of

Conterminous United States - Their Prediction and Interpretations",

USGS Professional Paper 1272, 1981, and "Predictive Model for

Important Ground Motion Parameters Associated with Large and Great

Earthquakes", USGS Bulletin 1838, 1988.

2-3 M. Legg, et. al., "Seismic Hazard for Lifeline Vulnerability

Analysis", Proceedings of the Third International Conference on

Microzonation, Seattle WA, 1982.

2-4 R.C. Wilson and D.K Keefer, "Predicting Earthquake-Induced Landslides

with Emphasis on Arid and Semi-Arid Environments", Landslides in a

Semi-Arid Environment with Emphasis on the Inland Valley of Southern

California, Editors: P. Sadler & D. Morten, 1989.

2-5 T.L. Youd and D.M. Perkins, "Mapping of Liquefaction Severity Index",

Journal of Geotechnical Engineering, V 113, No. GT 11, 1987, and

"Mapping Liquefaction-Induced Ground Failure Potential", Journal of

Geotechnical Engineering, V 104, No. GT 4, 1978.

3.0 SITE CONDITIONS AND LIFELINES

3.1 SITE CONDITIONS

This report section presents geologic and geotechnical information for the

Cajon Pass Study Area including:

8
a Fault information and ground rupture (displacement) potentials

o Seismic events

o Soil and bedrock conditions

o Ground shaking hazards

o Topographic and ground relief features and landslide hazards

o Hydrologic and ground water conditions and liquefaction

potentials

Discussions will also be presented on the earthquake hazards and

predictive models that can be used to evaluate the damage potentials

associated with the various earthquake hazards including: ground shaking,

landslide, and liquefaction hazards. In addition1 data (geologic,

geotechnical, hydrological, and groundwater) gathered in the course of the

project is presented. Actual applications of the predictive models to

analyze the damage potentials on the lifeline systems at the study area

will be provided in a separate, vulnerability analysis report to be

issued.

As shown in Figure 2.1, the study area covers approximately a 9.2 miles by

17.4 miles area (Longitude ranging from about 1170 21.91W to 1170 31.4 1W;

Latitude ranging from about 340 10.71N to 3a,4 261N). The study area

covers portions of nine 7.5 minute quadrangles (as designated by

U.S.G.S.): Phelan, Telegraph Peak, Cucamonga Peak, Baldy Mesa, Cajon,

Devore, Hesperia, Silverwood Lake, and San Bernardino North. As shown in

the figure, most of the lifelines at Cajon Pass generally follow the Cajon

Canyon corridor in the southern part of the study area. The San Andreas

rift zone intersects that lifeline corridor at the middle to southern part

of the Cajon Pass study area. In the high desert region in the northern

part of the study area the lifelines are spread apart to a greater degree

than is found in the southern regions.

3.1.1 Fault Information and Ground Rupture (Displacement) Potential

An excellent compilation of information on potential active faults that

could generate damaging earthruakes in Southern California has, been

presented by Ziony and Yerkes "

1 U. Figure 3.1-1 and Appendix A (which

defines the terms used in Figure 3.1-1) are extracted from their work.

They show that a number of different geologic faults can affect the Cajon

Pass. Also, many of the faults shown in Figure 3.1-1 but which are not

located directly within the Cajon Pass area still could present earthquake

hazards in terms of ground shaking to the lifelines in Cajon Pass. Figure

3.1-2 is presented to provide a more detailed map of the active faults

located within the study area that could present hazards related to

surface fault rupture or relative ground displacements.

9
Figure 3.1-1, Regional Fault Map

a

Ij I

1111 1 

10
I, I aUImm

- - - - -,-- -- - -

iqura 3.1-2 actisv Fault Locations

In The Study Araa

LargerScale Figure

Located at

End ofDocument
It can be seen from Figure 3.1-2 that the faults which are located within

the study area are:

(1) San Andreas fault zone (which is in Lone Pine Canyon).

(2) The San Jacinto fault zone (which generally follows Lytle Creek

Canyon and is south and parallel to the San Andreas fault),

including the following strands within the fault zone: (a) Glen

Helen fault, (b) several strands of San Jacinto fault, (c) Lytle

Creek fault, and (d) Punch Bowl fault.

(3) Faults along the southern margin of Transverse Ranges,

especially the Cucamonga fault which is further south of the San

Jacinto fault zone and which has two to three subparallel

strands located within the study area including the (a) Duncan

Canyon fault and the (b) Day Canyon fault.

(4) Faults along the margins of San Bernardino Mountains, the

Cleghorn fault (which is north and approximately parallel to the

San Andreas fault zone).

A discussion of each of the above four fault zones is presented below.

Aspects related to potential surface fault ruptures that are directly

relevant to lifeline damage evaluations are emphasized.

San Andreas Fault Zone. A very complete discussion on the San Andreas

fault can be found in California Department of Conservation Division of

Mines and Geology (CDMG) reports(31 3.1-3) and USGS reportsOA-4, 31-5). The

San Andreas fault zone is the most dominant active fault in California.

It is the main element of the boundary between the Pacific and the North

American tectonic plates. Two great historical earthquakes have occurred

along this fault: the renowned 1906 San Francisco earthquake and the

lesser known but possibly more severe 1857 Fort Tejon earthquake. These

two earthquakes were selected to serve as a basis for emergency planning

in Northern California(3 .16)and Southern California(3 17). Approximately

400 km of the San Andreas fault between Parkfield-Cholame (e.g., Central

California) and Cajon Junction (Southern California) ruptured during the

1857 Fort Tejon earthquake, which had an estimated magnitude of 8.3. The

southern end of the fault rupture during the Fort Tejon earthquake is

located within the study area (between Cajon Junction and Blue Cut). At

Cajon Pass, the San Andreas fault zone generally has been reported to

range from 0.3 to 1.5 km wide (0.2 to 0.9 miles). Bennett and

Rodgers(3 12) reported that although very pronounced surface crustal

movements can be observed north of Cajon Pass along the San Andreas fault,

very little movement has been recorded along the segment of the San

Andreas fault south of Cajon Pass.

San Jacinto Fault Zone. Echelon segments (including: the Glen Helen, the

various strands of San Jacinto faults, Punch Bowl fault, and the Lytle

Creek fault) of the San Jacinto fault zone system extend southeastward for

more than 300 km through the Imperial Valley and into northern Baja

California, Mexico. The zone at its northern end appears to merge with

12
the San Andreas fault at around the Cajon Pass region. For the past

century, the San Jacinto fault zone has been the most active earthquakegenerating feature in southern California; it has produced at least 10

earthquakes of about local magnitude 6.0 or greater since 1890. The

maximum credible earthquake associated with the San Jacinto fault zone is

a magnitude 7..5 earthquakes31 8 ).

Southern Marain of the Transverse Ranges. The southern boundary of the

western Transverse Ranges is formed by an overlapping group of west- to

east-northeast-trending, late Quaternary faults. 'Thesefaults, which dip

steeply to moderately northward, comprise an essentially continuous narrow

belt more than 300 km long that adjoins many of the major urban centers of

the Los Angeles region extending from Santa Barbara on the west to San

Bernardino on the east(3 1-9. Two to three subparallel strands of the

Cucamonga fault rift (ithe Duncan Canyon fault and Day Canyon fault)! which

may be as wide as wide as 1 km, are located at the southern part of the

study area. The maximum credible earthquake associated with this fault

system is a magnitude 6.5 earthquake.

Faults along the margins of the San Bernardino Mountains. The northern

edge of the San Bernardino Mountains is delineated by an arcuate group of

discontinuous faults that have various trends and that generally dip

southward into the mountain mass. The distribution and history of these

faults are poorly understood but are the subject of several current

investigation by State and Federal geological offices. The Cleghorn

fault, a single strand of the San Bernardino Mountain fault zone, is

located within the study area.

Figure 3.1-2 shows the fault locations within the study area. The fault

activities (expressed in terms of how recent has been the fault movement)

are depicted on the figure in terms of the thickness of the line. Fault

traces are indicated by solid lines where well located, by dashed lines

where approximately located or inferred, and by dotted lines where

concealed by younger rocks. From the referenced literature, it can be

concluded that zones of ground ruptures could be as wide as 1 to 1.5 km

along the depicted fault lines when the map is used to evaluate potential

damage to lifelines because of ground displacements related to fault

rupture.

A number of researchers( 3 .1-10, 31-11, 3.1-12, 3.1-13, 3.1-23) have related actual

rupture data (both length of break, displacement amount! and width of the

displacement zone) to the earthquake magnitude. Slemmons(3 .112) provides

lcg-log plots of data for North America. Bonilla(3 .1-14) also reported that

the maximum main fault zone (e.g., the width of the disruption) for

strike-slip faults is 320 feet. Rojahn(3 ,113 ) also provides equations and

plots that relate the maximum fault displacement to the earthquake

magnitude. These sources can be used in the current study to estimate the

ground rupture potential once the seismic event has been selected !(see

Section 3.1.4).

13
3.1.2 Soil and Bedrock Conditions

Areal differences in damage caused by shaking from earthquakes can be

related to variations in soil conditions, especially to those near the

surface (also see articles by Tinsley and Fumal and by Evernden in

reference 3.1-1). A comparison(3.113, 31-15, 31-16, 31-17) of the earthquake

shaking intensity maps of the 1906 San Francisco earthquake and that of

the 1989 Loma Prieta earthquake reveals that severe damage occurred to the

same locations where poor soil conditions exist, even though the

epicenters of the two earthquakes were physically removed for each other.

A number of recently completed studies on geologic mapping at the Cajon Pass(3 1 1 8 , 3.119, 3.1-20, 1-21) along with some traditional sources of

information 3 12 , 3.1-22 3.1-9) offers detailed information on the geologic

conditions at various locations in the study area. A number of scientific

research programs, including the first deep scientific drill hole in Cajon

Pass and the deep crustal seismic reflection profile at the western San

Bernardino Mountains, have recently been completed. Unfortunately, most

of the above studies cover a relatively small portion of the study area.

Traditional geologic mapping emphasizes the distribution and character of

bedrock units, including lithology, age, and rock structure (bedding foliation, lineation, fractures, folds, faults, etc.). Areas underlain by flood plain and other water-laid sediments commonly are depicted as a

single map unit, termed alluvium. Variation in the physical properties of

alluvial deposits that pertain to hazards of interest to earthquake evaluations, such as ground shaking and ground failure, are not usually distinguished on the standard geologic maps. Therefore, conventional

geologic maps have limitations with respect to evaluation earthquake

hazards.

In the past two decades, specialized mapping techniques directed

specifically at identifying and evaluating earthquake hazards in alluvial deposits have evolved(3,-23, 3-124, 3.1-25, 3.1-26, .1-27), all of which are summarized

in reference 3.1-1. However, such maps have only been presented for urban

development areas and are not available for Cajon Pass.

For the above reasons, the geologic maps of the San Bernardino Quadrangle compiled by Bortugno and Spittler(3-136 ) were selected for the present

study. An enlarged geologic map (scale: 1 inch = 1 mile) for the study

area is presented in Figure 3.1-3. The age of the bedrock and soil

deposit units denoted in the figure refers to various geologic times.

Some common terminology used to denote geologic time scales are summarized

in Appendix A, which is copied from reference 3.1-l1 In general,

alluvium, especially the Holocene alluvium, denoted as Unconsolidated

Alluvium, Q; Wash Deposits, Qw; Older Wash Deposits, Qow; Younger Alluvium, Qya; Younger Fan Deposits, Qyf, Fan Deposits, Qf; Wind-Blown

Sand, Qs; Large Landslide Deposits, Qls and lake Deposits, Ql would

present the most seismic hazard potentials (in terms of ground shaking, liquefaction and landslide and ground failure). For convenience, the

locations of high ground water table have been identified in the figure.

14
as tl7 R n

SCALE O0 , 2MIUtt

5_,2 fLwcwn 4' Figure 3.1-3 Cajon Pass Region Geologic Units With High Water Table Regions Identified

EXPLANATION

//M/

.... YT TA&Z

5 " GESfSITS Ei [El OLDERVkS DEPOSITS Uhf

Ei1 LAEDSLUDCDE2s2T5 S

Oji TCUll i.U DSITS01

ft EIIra OEMITSI

WLLDISSECTTEALLUTIALFiAS Ei3 ISM A FO T30Mf JAXsU EER GRAtV Q tCI C FCUJIIE

FRPI nW Ill FONUTISNOF WONEFA1iL1T

_- ISEZOCIEESISST OSSEOUSCt OPISSLMeTaXTLOCAlE;- UIllt sInII~ GAAMTLSELtK ItflEEO1.

YAQUEllS[0?] IDltTID

TLITIlETMA30LTIClEC

SAXtUlCMISOIITOill FoeaTIDt

PELDM MUST5

UiTACtEOS GWIuTIC 1=tS

CEhTACEgOw U1 Si~S 01TE CUTACECUSDRSALSSIC GiRtZ PWZOUTE. OLUT1 AMO*3E OOF PLULSM TsEERIDGE

JAA5DECORtTAEOUS GAMJWNTZ

AM' OF ILEASAEtYIEY RlIDE

ITAsUDIMITAT M0.5 OF UNCERTALIAM

SWInEDAX2DE; W ETAERIxIC texs im Et=Mx] fl.GEISS

*4 laGat METAWWICM25S

LargerScale Figure

Located at

EndofDocument

15

nz~Il I
West of the San Andreas fault, a basement rock unit referred to as the

"Pelona Schist", or "ps", is the most landslide prone basement rock unit

in the Inland Valley region of Southern California(31 19 ). A number of

major deep-seated landslides 3 11 7' 3.1-28) in the region are underlain by the

Pelona Schist. The Pelona Schist is comprised of several rock types but

is mainly a fissile, white mica-albite-quartz schist that is relatively

weak and distortable. A variety of landslides, regardless of the

physically setting, have been recorded at the Pelona Schists. The

landslides that have impacted the Cajon Pass electrical lifelines (see

Section 3.3) and the natural gas pipeline lifeline (see Section 3.4) have

occurred in schist deposit areas.

3.1.3 Seismic Events

Four seismic source zones have been identified within the study area and

have been discussed in the preceding section ( Section 3.1.1). Although

other nearby faults or seismic source zones need to be considered when

hazards associated with ground shaking are studied, the main hazards would

be associated with the four fault zones within the study area.

Furthermore, the San Andreas fault, which is highly active and could

generate significantly larger magnitude earthquakes, would dominate the

seismic loading considerations. Although the San Andreas fault has atotal fault length exceeding 1000 km, seismologists and geologists

anticipate that only a portion of the San Andreas fault would rupture in a

single event. The fault is divided in three major segments which could

generate very large magnitude earthquakes:. (1) the northern segment from

Point Delgada to San Juan Bautista (roughly coincident with the 1906 San

Francisco earthquake fault rupture), (2) the central segment from around

Parkfield to Cajon Pass (coincident with the 1857 Fort Tejon earthquake),

and (3) the southern (Mojave) segment from Cajon Pass to Salton Sea. The

maximum credible earthquakes associated with the central and the southern

segment of the fault is a magnitude 8.25 and'a 7.5 event 3 ,18),

respectively. Both the central and the southern segments have been judged

to be highly active 31 29 ), with a probability of sizable earthquakes

exceeding a 40 percent chance over a 30-year exposure time. However,

since Cajon Pass marked the end points of fault rupture associated with

the two events, the damage scenario for the Southern California region as

a whole due to disruption of major lifelines may be remarkably different

depending on which event is chosen for damage evaluation. A potentially

more damaging third event scenario associated with a fault rupture

centered roughly at Cajon Pass and extending both northward beyond

Palmdale (where another major natural gas pipeline crosses the San Andreas

fault) and southward to beyond Thermal, California (where still another

major power transmission line and also a natural gas pipeline cross the

San Andreas fault) could be a plausible event.

Lifelines in general and especially electric power towers and buried

lifelines, with the exception of highway and railroad bridges, have

survived ground shaking effects remarkably well. Surface fault rupture

and ground failure (including landslides and liquefaction) potentially

would be more damaging to lifelines. Therefore, although the San Andreas

fault would present the most intense ground shaking damage, other smaller

16
faults which could generate surface ruptures at locations within the study

area will need to be evaluated in terms of ground displacement effects.

3.1.4 Ground Shaking Hazards

Various models can be adopted to predict ground shaking for a given

seismic event depending on the desired ground shaking parameters,

including:

o seismic intensity;

o peak ground acceleration, velocity and displacement;

o ground shaking durations; and

o frequency content.

Models to predict fairly detailed ground shaking parameters, including

peak ground acceleration, velocity, duration, and frequency content in

terms of overall the overall shape of spectral intensity magnitude at

various period ranges have been developed(3 "23 ). However, while such a

model would be ideal for a local site-specific evaluation, they are not

suitable for use in regional analysis such as being performed in this

study.

A models3 ' 3 3-131) which has been developed ,can be used to predict seismic

intensities in terms of both Rossi-Forell (RF) and Modified Mercalli

Intensity (DMI) scales for regional risk evaluations. Other ground motion

parameters (e.g., peak ground acceleration, velocity and displacement) and

the damage potential to a variety of structures can then be postulated

from correlation-of the intensity at the structures location by using

historical data on intensity-failure effects, 3 113 1. This approach has been

used by Davis et. al.(3.1-6, 3.T-7) to estimate the general effects of

hypothetical great earthquakes along the San Andreas fault on the lifeline

systems in the Los Angeles and San Francisco metropolitan areas. This

approach is expected to be used to predict the seismic intensity and

resulting Cajon Pass lifeline damage from the various postulated

earthquake events associated with the San Andreas fault and the other

fault zones identified in Section 3.1.1.

The USGS seismic shaking intensity model 3 1-30 3.131) has been coded in a

computer program QUAK2NW3. Input to the program consists of:

(1) A fault data file, which represents the fault to be analyses, as

a series of uniform point sources spaced as closely as

desirable.

(2) A ground condition data file which performs two functions. It

establishes each calculation point with respect to the fault,

and it provides the soil condition at each calculation point.

Ground conditions are typically discretized into 0.5 minute

latitude by 0.5 minute longitude grids by the code developers.

17
(3) A pseudodepth term "C" which is chosen to give proper near-field

die-off of the shaking intensities as a function of distance

from the fault.

(4) An attenuation parameter "k" which controls the rate of die-off

of peak acceleration as a function of distance from the fault.

With the above input data, the computer program QUAK2NW3 computes the

acceleration associated with the energy release at each point source along

the fault(3 1

3 2 ). Then, the shaking intensity value is computed from the

acceleration value. The shaking intensity is first calculated for a

standard reference ground unit condition (e.g. saturated alluvium). Then,

the intensity value at each grid point is adjusted for the actual ground

condition specified in the ground condition input data file. Using this

model, the model developer has predicted the patterns of intensity for

many of the large earthquakes occurred throughout the United States. Many

of these predictions compared favorably with the intensity iso-seismal

maps estimated from historical recordst3131).

The USGS model will be used to predict the shaking intensity at the Cajon

Pass region for all the referenced faults identified in Section 3.1.1.

Several analyses will be conducted to evaluate the sensitivities of the

various event scenarios postulated for the San Andreas fault, so that an

appropriate scenario can be selected for the subsequent vulnerability

analysis.

3.1.5 Topographic and Ground Relief Features and Landslide Hazards

A number of publications(311 9 ,3.1-30, 3.1-38, 3.1-39) were reviewed and observed

relics of landslides were used to develop a landslide map at Cajon Pass;

this is shown in Figure 3.1-4. It was concluded that earthquake shaking

will be one of the main triggering agents for landslides in the Cajon Pass

area. A photograph showing very significant recent landslide scars where

the Southern California Power Edison Co.'s power line transmission towers

are located is presented as Figure 3.1-5. Figure 3.1-6 shows a typical

landslide scar in the Lone Pine Canyon, the canyon which contains the San

Andreas fault rift zone. It can be seen on Figure 3.1-4 that there are

numerous landslide features at the Cajon Pass especially at areas where

the Pelona Schist, ps, is the basement bedrock geologic unit. As

discussed earlier, the Pelona Schist is the most landslide prone bedrock

unit known in the study area 3 -1-33 ). This landslide map is presented to

serve as an inventory of observed or recorded landslide features at the

study area. It also can be used to validate landslide prediction models

and analyses to be conducted in the subsequent damage evaluation report.

Although there are numerous analysis methods to analyze landslides for a

variety of loading conditions (gravity, ground water seepage forces, and

earthquake) in the literature, they are almost exclusively intended to be

used for site specific studies. A frequently used analysis model for

evaluating earthquake induced landslides that can be used in regional

evaluations is a model presented by Wilson and Keefers3- 3 8' 3-140). Their

model has been used to analyze and correlate with slope failures from the

18
LargerScale Figure

Located at

End ofDocument

?iqurs 3.1-4 Obsaeved Landslides Within the Study Area

19
August 6, 1979,


Coyote Lake,


California,


earthquake and the


1989 Loma Prieta


earthquake.


Preliminary


information


indicates that there


is good agreement


for the prediction


with the Loma Prieta


earthquake landslide


data. Wieczorek(31


37) applied the 

analysis method to


develop a map of


relative landslide


potential during


earthquakes in San


Mateo County,


California. Nilsen,


et. al. 3 -1-39) also 

applied the method


in a project jointly


supported by USGS


and the Department


of Housing and Urban


Development to


develop maps of


relative slope


stability for land-


use planning in the


San Francisco Bay


region, California.


-

-

� I --- -- - - . - - I ­

figure 3.1-5 Rebu1lt Power Transmission Towers on a 

Landslide Scar


Figure 3.1-6 Landslide Scar in Lone Pine Canyon Along


The San Andreas Fault Zone


20

Wilson's method consists of the following basic steps:

Step-1 Solve for the factor of safety of the slope for a given

combination of slope angle and soil strength.

Step-2 Using the Newmark method 3--43) and the factor of safety from

Step-1, calculate the critical acceleration value which is

the level of ground acceleration required to initiate

downward slope movement.

Step-3 The above critical acceleration value can then be used in

conjunction with a given design earthquake to solve for the

magnitude of accumulated downslope movement associated with

the design earthquake. This magnitude of accumulated slope

movement is then used as an indicator of the potential for

slope failure.

Wilson has presented several simplifying charts to facilitate application

of the above procedures and they are summarized by Rojahn 3 3

'.

Existing information indicates that earthquake-induced landslides could

pose significant damage to the lifelines at Cajon Pass. An evaluation of

landslide potential will be very important in the current project.

Wilson's method will be used to develop a map of the landslide potential

at Cajon Pass. The digital elevation model data acquired in the course of

the project will be used to develop a topographic map and subsequently a

map of the ground relief data. Shear strength values will be assigned to

each of the geologic units on the Cajon Pass geologic map. The ground

relief and the shear strength maps will be used to calculate the critical

acceleration value at each grid point in the study area. The critical

acceleration and the MMI index value can be used to enter the tables

provided by Rojahn to identify the slope failure state. The slope failure

state can then be related to the lifeline damage state. This is similar

to the analysis method of Wieczorek"3 -37 , where the landslide

susceptibility was estimated in terms of a critical ground acceleration

and a calculated slope displacement value. -One advantage of this proposed

method is that it relates the landslide susceptibility to the Modified

Mercalli Indices as well as the geology and the slope of the surface

formations.

3.1.6 Hydraulic, Groundwater Conditions, and Liquefaction Potential

The study area is situated far from oceans. There are also no major

hydrologic features (lakes, rivers) within the study area. There are a

number of minor creeks and streams (e.g. Lytle Creek Wash, Cajon Wash

within the study area) which could be carrying large volume surface water

during the rainy season (winter) or during flash floods. Therefore, areas

where liquefaction could occur in the study area would be locations where

the water table is close to the surface. The ground water table at Cajon

Pass could fluctuate in relation to precipitation and ground-water

management (3.1 34K. As an example from outside of the study area in the City

of San Bernardino, the regional long-term trend is a lowering of the

21
ground-water table due to withdrawal from water wells, although the City

of San Bernardino is currently experiencing a rise in the depth-to-groundwater due to the reduction in agriculture and its impact on reducing the

withdrawal rate of ground water in that specific local region. Available

depth-to-ground-water maps"3 --35 indicate that, in general, the water table

will be relatively deep (over 100 feet) over most of the study region.

However, perched water tables (5-20 feet deep) exist at isolated pockets

within the study area.

In an effort to locate these pockets of higher perched water table zones,

water-well data from the Department of Water Resource was examined.

Locations of the water wells are identified in a map presented in Figure

3.1-7. Detailed information for the water well, including depth of the

water table and date of the observation, are tabulated in Table 3.1-1.

The water-well data were then divided into two categories:

o Shallow water table (depth less than 30 feet).

o Deep water table (depth more than 30 Feet).

Locations of shallow water table conditions are identified in Figure 3.1-

4. and Figure 3.1-7. These are the locations where liquefaction could

occur during an earthquake. It should be noted that due to the rugged

terrain and sparse population in the study area, there is simply no well

water data available over much of the Cajon Pass area. Therefore, it is

fair to say that the map is incomplete andother locations with high

perched ground water table could be present within the study area. Also,

the dominance of fault features in the region adds complexities to the

evaluation of the ground-water table conditions. Major faults appear to

act as barriers to downslope movement of ground water, especially the San

Andreas fault, as indicated by seeps and springs along many parts of the

fault, particularly where it transects alluviated flood plains of canyons

or alluvial slopes. In many instances along major faults, the ground

water on the upslope side apparently backs up against the fault, which

acts as an "underground dam", and the overflow reaches the ground surface

as springs. The water table on the upslope side of the fault could be

several tens of feet higher than on the downslope side of the fault. An

example of this in the study area is the gravel pit located just south of

Cajon Junction. On the upstream side of an apparent schist "dam" the

water table is within 5-7 feet of the surface. Downstream of the schist

the gravel pit operator had removed gravel at 50-70 feet below the surface

and the pit was dry (when observed in the fall of 1990).

Although, widespread liquefaction is not expected at the study area, at

local sites where the lifelines are collocated it can be anticipated that

liquefaction could be the major factor for imposing collocation loads on

the individual lifelines.

There are several liquefaction analysis approaches that can be used for

regional evaluations. The most recognized model is the one by Youd and

Perkins 3 . 4 1 ' 3.142). The procedure used to determine areal variations in

liquefaction potential requires the development of a liquefaction

22
aru~~~~a enu -- -- 11°7fl.

- e~l_ JZ </- jt

AN'sw~ ~ ~ A

i ~~~~-

K_ - ^- C _ _ .-e a - ' - \'i ax,)s,. _._

k1w

1s~~~- , . - u !

. .. '~~ -. - Cn-'

.~~~~~~~~ _-- _.rn~_ ~ ~~~~~~~~ 

X ~ ~ ~ ~ ~ ~ 1 -i~ -- |!~-

sn ~ ~ ~ C J '

( 4~~~~~~~

MX)UW~flWIT

S. -tJ _ -lre eFgr

- N -w as

C.en

Flg 3-1-7 ticrL oS Sballor Yrz~r T* 4u .

- I~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~7

*~~'\ ~ ' ~ WWe Ob ~ ~S0. ~~~ C4~~, wW 76S ti

% 'a~~~~sa

* - I' ~~~~~~ -w-----4="A Mt Tu~~~~~SW-

* sumsas ins~~~~~~~sem

o nuns unearM

us a ja: M mua-aemu i LargerScale Figure VA4I f~0 a m ww -w un- Locatedat

Piqura 3..1-7 Locatiwi of Msalicv Water Tablm Cmnditis En f oumn

23

I

i

I

i

i

i

I

i

L

1
Table 3.1-1, Depth to Ground Water Measured From Wells

Reference No.

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

17

17

18

19

20

21

21

22

23

24

25

26

27

28

29

30

31

32

33

34

35

36

Township &

Section No.

3N5W/l 1

14

14

19

20

21

22

22

26

26

27

27

27

27

27

27

28

28

28

35

2N5W/l 1

13

13

13

13

13

13

13

13

13

15

15

15

15

24

19

19

19

19

Range State

Well No.

R2

DI

Ni

Ml

Qi

Ri

E2

Ml

El

Ml

Al

Bl

B3

B4

Gl

P1

A6

A7

A8

Al

Bi

El

Kl

Kl

Ml

M2

Ni

N2

01

03

F3

Ji

Li

L2

Al

Dl

K1

K2

01

24

Year

1984

1963

1984

1986

1964

1963

1974

1978

1980

1988

1963

1964

1963

1988

1979

1987

1972

1974

1977

1988

1955

1967

1951

1960

1967

1967

1967

1967

1964

1967

1964

1980

1986

1985

1985

1979

1970

1987

1983

Depth (ft)

410

255

200

49

144

8

70

110

21

40

60

48

15

42

30

FLOWING

84

60

70

12

28

7

70

70

17

1

14

4

24

13

4

25

35

30

50

50

DRY

37

5
Table 3.1-1, Depth to Ground Water Measured

(Continued)

From Wells

Reference No.

37

38

39

40

41

42

43

44

45

45

46

47

47

48

49

50

51

52

52

52

53

54

55

56

57

58

59

60

61

61

61

61

61

61

61

61

61

61

Township & Range

Section No.

2N5W/1 

20

22

27

27

27

28

33

33

33

33

I N5W/3

3

3

6

6

6

7

7

7

7

7

8

8

8

2N6W/22

22

22

22

22

22

22

22

22

22

22

22

22

State

Well No.

RI

P1

El

KI

Li

L2

Cl

F1

KI

KI

ml

Al

Al

A2

GI

KI

K2

Hi

Hi

HI

H2

Ji

81

Ni

Q1

Fl

F2

Gi

LI

L2

L4

L5

L6

U

L8

L9

LI 0

Year

1967

1967

1975

1978

1974

1974

1956

1950

1950

1983

1979

1927

1982

1952

1987

1953

1987

1931

1977

1987

1918

1918

1938

1918

1918

1988

1987

1988

1988

1987

1986

1985

1985

1985

1985

1985

1985

1987

Depth (ftT

13

10

143

100

180

140

32

130

83

84

25

125.

142

145-200

75

DRY

91

126

117

100

63

172

60

132

107

77

70

11

52

35

38

60

64

60

25

10

/60

50

25
Table 3.1-1, Depth to Ground Water Measured

(Continued)

From Wells

Reference No.

61

61

61

62

63

64

65

66

67

68

69

70

71

72

73

74

75

76

77

77

78

79

80

81

82

82

82

83

83

83

83

84

85

Township & Range

Section No.

2N6W/22

22

22

22

24

25

26

26

26

27

27

1N5W/ 2

2N5W/26

26

26

26

26

35

35

35

35

35

35

35

35

35

35

35

35

35

35

35

35

State

Well No.

LI 1

Li 2

L13

P1

Cl

LI

Bi

Li

L2

Cl

Gi

Kl

G2

Kl

Ml

P1

Q2

BI

Cl

C2

C3

DI

El

Gi

Kl

K2

K3

L2

L3

L4

L6

L5

Q1

Year

1986

1987

1986

1986

1967

1985

1978

1982

1973

1985

1985

1988

1979

1978

1977

1979

1978

1978

1977

1978

1979

1980

1979

1977

1988

1978

1978

1980

1978

1978

1985

1979

1977

Depth (ft)

40

65

32

9

31

54

117

15

45

8

6

121

180

100

80

40

22

90

200

100

20

150

165

200

121

90

65

60

85

95

113

32

60

26
susceptibility map and a liquefaction opportunity map. A liquefaction

susceptibility map delineates areas where liquefiable materials are most

likely to be present and is based chiefly on generalizations pertaining to

the geology and hydrology of late Quaternary deposits in a sedimentary

basin. The liquefaction opportunity map shows regions of earthquake

shaking strong enough to generate liquefaction in susceptible materials

and is based on an appraisal of regional earthquake potential. These two

maps are then considered together to determine liquefaction potential, the

relative likelihood that an earthquake will cause liquefaction in watersaturated cohesionless silts and sands that may be present. The use of

this approach can also be validated with the analysis *ofRojahn:3 3

s where

the liquefaction potential has been presented in a table and alternatively

by the standard penetration resistance (e.g., blow count data) of the

soils.

3.1.7 Bibliography For Section 3.1

3.1-1 J.I. Ziony & R.F. Yerkes, "Evaluating Earthquake and SurfaceFaulting Potentials', Evaluating Earthquake Hazards in the Los

Angeles Region-An Earth-Science Perspective, USGS Professional

Paper 1360, 1985.

3.1-2 "San Andreas Fault in Southern California : A Guide To San

Andreas Fault from Mexico to Carrijo Plain", California Division

of Mines and Geology (CDMG) Special Report 118, 1975.

3.1-3 "Earthquake Hazards and Tectonic History of the San Andreas

Fault Zones, Los Angeles County, California", CDMG Open-file

Report 85-10, 1985.

3.1-4 D.C. Ross., "Map Showing recently Active Breaks,Along the San

Andreas Fault Between Tejon Pass and Cajon Pass, Southern

California", U.S. Geological Survey, Miscellaneous Investigation

Series, Map I-553, 1969.

3.1-5 "IThe San Andreas Fault System", USGS Professional Paper 1515,

Editor R.E. Wallace, 1990.

3.1-6 J.F. Davis, et. al., "Earthquake Planning Scenario for a

Magnitude 8.3 Earthquake on the San Andreas Fault in Southern

California", CDMG Special Publication 60, 1982.

3.1-7 J.F. Davis, et. al., "Earthquake Planning Scenario for a

Magnitude 8.3 Earthquake on the San Andreas Fault in the San

Francisco Bay Area", CDMG Special Publication 61, 1982.

3.1-8 R.W. Greensfelder, "Maximum Credible Rock Acceleration From

Earthquakes in California", CDMG Map Sheet 23, 1974.

3.1-9 "Recent Reverse Faulting in the Transverse Ranges, California",

U. S. Geological Professional Paper 1339, 1987.

27
3.1-10 M. Bonilla and J. Buchanan, "Interim Report on Worldwide

Historic Faulting", USGS Open-File Report, 1970.

3.1-11 M. Bonilla, et. al. "Statistical Relations Among Earthquake

Magnitude, Surface Rupture Length, and Surface Fault

Displacement", USGS Open-File Report 84-256, 1984.

3.1-12 D. Slemmons, "Determination of Design Earthquake Magnitude for

Microzonation", Proceedings of the 3rd International Conference

on Microzonation, Seattle, Washington, 1982.

3.1-13 C. Rojahn and R. Sharpe, "Earthquake Damage Evaluation Data for

California", ATC-13, 1985.

3.1-14 M. Bonilla, "Historic Surface Faulting in Continental United

States And Adjacent Parts of Mexico," USGS Report (NTIS No. TID24124), 1967.

3.1-15 "The Loma Prieta Earthquake of October 17, 1989, What

Happened..... What is Expected..... What can be Done", USGS Memo,

January 1990.

3.1-16 "Lessons Learned from the Loma Prieta, California, Earthquake of

October 17, 1989", USGS Circular 1045, G. Plafker and J.P.

Galloway, Editors, 1989.

3.1-17 "Loma Prieta Earthquake Reconnaissance Report", Earthquake

Spectra, The Professional Journal of the Earthquake Engineering

Research Institute, Supplement to Volume.6, Earthquake

Engineering Research Institute (EERI), May 1990.

3.1-18 K.E. Meisling and R.J. Weldon, "Late Cenozoic Tectonics of the

Northwest San Bernardino Mountains, Southern California",

Geological Society of America Bulletin, V. 101, pp. 106-128,

January 1989

3.1-19 P.M. Sadler and D.M. Morton, Editors, "Landslides in a Semi-Arid

Environment with Emphasis on the Inland Valleys of Southern

California", Landslides in a Semi-Arid Environment, Publications

of the Inland Geological Society, Volume 2, 1989

3.1-20 R.J. Weldon, "The Late Cenozoic Geology of Cajon Pass;

Implications for Tectonics and Sedimentation along the San

Andreas Fault", Ph D. Thesis, California Institute of

Technology, Pasadena, California, 1986.

3.1-21 R.J. Weldon et. al., "Implications of the Age and Distribution

of the Late Cenozoic Stratigraphy in Cajon Pass, Southern

California," San Andreas Fault, Cajon Pass to Wrightwood,

American Association of Petroleum Geologist, Pacific Section,

Volume and Guidebook Number 55, R. Hester and D. Hallinger,

editors, 1984.

28
3.1-22 T.W. Dibbles, Jr., "Areal Geology of the Western Mojave Desert,

California", USGS Professional Paper 522, 1067.

3.1-23 W.B. Joyner and T.E. Fumal, "Predictive Mapping of Earthquake

Ground Motions" , Evaluating Earthauake Hazards in the Los

Angeles Region, USGS Professional Paper 1360, J.I. Ziony,

Editor, 1985.

3.1-24 K.R. Lajoie and E.J. Helley, "Classification and Mapping of

Quaternary Sediment for Purposes of Seismic Zonation', Studies

for Seismic Zonation of San Francisco Bay Region, R.D. Borcherdt

editor, USGS Professional Paper 941-A, 1975.

3.1-25 R.D. Borcherdt, "Effect of Local Geology on Ground Motion near

San Francisco Bay", Bulletin of Seismological Society of

America, v. 60, p. 29-61, 1970.

3.1-26 R.D. Borcherdt, et. al., "'Response of Local Geologic Units to

Ground Shaking", Studies for Seismic Zonation of San Francisco

Bay Region, editor R.D. Gorchert, USGS Professional Paper 941-A,

1975.

3.1-27 "Landsliding and Mudflows at Wrightwood, San Bernardino County,

California"3 , USGS Special Report 136, 1979.

3.1-28 "Geologic Hazards in Southwestern San Bernardino County,

California", USGS Special Report 113, 1976.

3.1-29 T.C. Hanks, "The National Earthquake Hazards Reduction ProgramScientific Status", USGS Bulletin 1659, 1985.

3.1-30 J.F. Evernden, et. al., "Seismic Intensities of Earthquakes of

Conterminous United States - Their Predictions and

Interpretations', USGS Professional Paper 1223. 1981.

3.1-31 J.F. Evernden and J.M. Thompson, "Predictive Model for Important

Ground Motion Parameters Associated With Large and Great

Earthquakes", USGS Bulletin 1838, 1988.

3.1-32 J.F. Evernden, et. al., "Interpretation of Seismic Intensity

Data1", Bulletin of the Seismological Society of America, v. 63,

1973.

3.1-33 D.M. Morton and R. Streitz, "Preliminary Reconnaissance Map of

Major Landslides, San Gabriel Mountains, California", CDMG Map

Sheet 15, 1969.

3.1-34 "San Bernardino County General Plan Update Background Appendix

Draft: Water Distribution Systems, Groundwater Supply and

Quality", Environmental Public Works Agency-Land Management

Department, Office of Planning, Pages 113-165, April 1989.

29
3.1-35 "Meeting Water Demands in the Bunker Hill-San Timoteo Area",

State of California, The Resources Agency, Department of Water

Resources, Bulletin No. 104-5, December 1970.

3.1-36 E.J. Bertugno and T.E. Spittler, "Geologic Map of the San

Bernardino Quadrangle", CDMG Geologic Map Series, Map No. 3A

(Geology), 1986.

3.1-37 G.F. Wieczorek, et. al., "Map Showing Slope Stability During

Earthquakes in San Mateo County, California", USGS Map I-1257-E,

1985.

3.1-38 R.C. Wilson and D.K. Keefer, "Predicting Aerial Limits of

Earthquake Induced Landsliding", Evaluating Earthquake Hazards

in the Los Angeles Region, USGS Professional Paper 1360, J.I.

Ziony, Editor, 1985.

3.1-39 T.H. Nilsen, et. al., "Relative Slope Stability and Land-Use

Planning in the San Francisco Bay Region, California", USGS

Professional Paper 944, 1979.

3.1-40 R.C. Wilson and D.K. Keefer, "Dynamic Analysis of a Slope

Failure From the 6 August 1979 Coyote Lake, California,

Earthquake", Bulletin of the Seismological Society of America,

Vol. 73, No. 3, pp. 863-877, 1983.

3.1-41 T.L. Youd and D.M. Perkins, "Mapping Liquefaction-Induced Ground

Failure Potential", Proceedings of the American Society of Civil

Engineers, Journal of the Geotechnical Engineering Division, V

104, No. GT4, 1978.

3.1-42 T.L. Youd and D.M. Perkins, "Mapping of Liquefaction Severity

Index", Journal of Geotechnical Engineering, V 113, No. GT 11,

1987.

3.1-43 N.M. Newmark "Effects of Earthquakes on Dams and Embankments",

Geotechnique, V 15, No. 2, p. 139-160, 1965.

3.2 COMMUNICATION LIFELINES

The Cajon Pass region includes hardwired and fiber optic telephone systems

and microwave and radio towers. The hardwired telephone primarily

services the local distribution system. The fiberoptic lines primarily

are transmission and major trunk lines. The microwave and radio towers

serve both local communications within the Pass and transcontinental

communication, but separate towers are used to support local or long

distance transmission. The tower systems are identified in this study for

completeness, but they are mostly isolated and thus have no direct

collocation impacts. Figure 3.2-1 is a map of the communication

lifelines. For reference purposes, the location of photographs provided

in this Section are also shown on the Figure. Consistent with the concept

used for evaluating other lifeline systems (that is, this study focuses onthe

30
" 117' 

Figure 3.2-1 Map of the Comunication Lifelines

SCALE 1 2 urW

0 7 onm I LargerScale Figure

Locatedat

End ofDocument

EXPLANATION

-~ i-az

I -I

. 7-- - 7- 3nc1nc cn

31

C,

;: 4

It? 21 30

I B;|-

o
transmission or primary systems and


not the local or distribution


systems), the hardwired and wooden


pole telephone systems were not


included in this study. However,


the fiber optic systems are similar


to a transmission system in that


they are used to transfer many


calls between the Los Angeles Basin


and other regions in the nation.


Thus, they were included in detail


in this study. There are no state


or Federal documented seismic


criteria or standards for the


installation of fiber optic cables,


hence each company is free to


include seismic considerations as


it determines necessary.


3.2.1 Fiber optic Cables 

On-site surveys identified that


five fiber optic systems are


located in the study area. They


are American Telephone and


Telegraph (AT&T), Continental


Telephone (CONTEL), MCI


Communications (MCI), WilTel (now


WTGWest) and US Sprint. 

Contact(3,) was made with these


-C_- -- %MCM 01PYLTMl8'y -A rTeT .L .LIm, CUILLAl Et l, L.LAj, a.In U> C.vv-int r4cnndaA i h i fnrgvma+ n -Max-.. .c-w.. -54., - -- _ -- -- . Figure Looking on Old i 3.2-2, North Review of the U.S. Forest Service Highway 66 (Now Cajon Canyon Rd.)


maps, on-site evaluations, and


contact with the California Utility


Underground Service were used to supplement the information and to obtain


additional details on the routing of the various systems.


A fiber optic cable is a multi-layered cable with an inner structure that


allows the cable to be pulled and maintained in a state of tension without


putting tension on the individual glass fibers. Various materials are


used for insulating the glass fibers, including a metal sheath. In the


fall of 1986, both MCI and WTG West contacted the U.S. Forest Service to 

obtain right-of-ways for their cables (See Figure 3.2-1). To reduce the


number of locations where trenching would be required, the Forest Service


required each of those firms to trench conduits that could support four


different fiber optic systems (for a total of eight systems in the two


routes). They also required that the routes coincide whenever possible,


so from just north of the Cajon Junction to the southern end of the old


Cajon Canyon Road the cables are collocated (see Figure 3.2-2 which is a


photograph of the old Highway 66, now called Cajon Canyon Rd.. Note that


the divided highway has been converted to a two lane highway by blocking


32

the eastern side of the road). Each of the firms installed two metal

conduits. They are four inches in diameter and can accommodate up to

three separate fiber optic cables in each conduit, although it is

anticipated that at most eight separate firms will actually install cable

in the conduits. AT&T was the last firm to install their cable,

completing the work in late 1989.

The separate telephone connections for AT&T, MCI, US Sprint, and WTG West

are parts of a much larger network owned by each of those companies. If

there were problems with the cables in the Cajon Pass, the companies

indicated that by rerouting the calls they could continue their service.

A similar situation exists for CONTEL, except that they do not maintain as

many separate lines from their Victorville, California, center to their

Los Angeles Basin center. Thus, they may have to reroute their calls

using the existing lines of one of the other firms identified above. The

exact excess rerouting capacity of each firm is confidential.

Referring to Figure 3.2-1 and starting from the southern edge of the study

area, the AT&T cable enters from San Bernardino on the eastern side of the

study area. Much of its route is along city streets in San Bernardino and

Devore, where AT&T already had existing right-of-ways. Part of the cable

path is along the street parallel and next to I-215 (Outer Highway and

Little League Drive). It crosses under highway I-15 at the Kenwood

exchange. From there it enters the cable conduits installed by WTG West.

The US Sprint cable also enters the study area from the Rialto area. It

travels north on Sycamore street, then east on Highland Ave., then north

on Macy St. until it insects Cajon Boulevard. It travels northwest along

Cajon Blvd. parallel to the Atcheson Topeka and Santa Fe (AT&SF) and the

Union Pacific railroads. At Devore it turns northeast along Devore Road.

It crosses under I-215 along Devore Road and then turns parallel to I-15

along Nedlee Ave.. Just north of the I-15 and I-215 intersection it

crosses under 1-15 and connects to the existing fiber optics conduit

(which was installed by MCI) located along the old Highway 66 (which is

parallel and west of I-15). The WTG West cable enters the study area from

the western side of the southern boundary. It heads northeast along

Devore Road (which is north of and roughly parallel to I-15). It crosses

the Lytle Creek Wash, turns south, and then crosses under I-15 where it

continues to follow Devore Road. Next it enters Cajon Wash and crosses

under the AT&SF and the Union Pacific railroads, then it turns northwest

and crosses under I-15 near to the US Sprint cable. It enters the

existing conduit at the same location that the US Sprint cable enters it,

but it enters a different conduit. Also located in one of those two

conduits is the CONTEL cable. The CONTEL fiber optic cable enters the

study area from San Bernardino from the southeast study boundary. It

moves northwest along Cajon Blvd., turns east on DeVore Road and crosses

under I-215. It follows Devore Rd., turns west along Kenwood Ave.,

crosses under I-15 along Kenwood Ave., and enters the conduit installed by

MCI.

The fiber optic conduits (four in number) are located together and run

mostly along the median region of the old Highway 66 (see Figure 3.2-2

which shows the general nature of the old highway and the wide nature of

33
-

the Cajon Pass in


that region).


Again, in order to


limit the amount of


potential


environmental damage


due to trenching,


the U.S. Forest


Service had the


fiber optic cables


located parallel and


near to the existing


two petroleum


product pipelines


(an eight and a 14­


inch line). The are


routed in the median


zone of the old


Highway 66. The


cables are located


from one to four


feet from the


pipelines and are


buried three to four


feet deep (during


the cable trenching,


the pipeline


operator indicated


that the trencher


struck the pipeline


on at least two


occasions, requiring


repair efforts by


the pipeline owner).


However, at bridge


or culvert locations


they are routed


above ground along


the bridge or above


the culvert but


still underground.


Figure 3.2-3 is a


typical example of


the supports used to


hang the cable


conduits from the


bridge. Earthquake


criteria were not


used in designing


these supports. It


is noted that this


Figure 3.2-3 Fiber Optic Conduits Crossing a Cajon


Canyon Road Bridge


L 

Figure 3.2-4 Details of the Fiber Optic Conduits and


Hangers on a Cajon Canyon Road Bridge


34

side of the Cajon


Canyon Road and the


bridge are


"abandoned" and some


concrete spalling of


the piers was noted


during the site


inspections. Figure


2.3-4 gives further


details of the


conditions of the


conduits and their


wall supports.


Continuing north,


the cables pass at


the toe of a crib


wall used to retain


the southbound lanes


of I-15 (see Figure


3.2-5). That site


is a potential


liquefaction site


due to the high


water table and


alluvium deposits.


Immediately north of


the crib wall the


conduits are brought


to the surface and


hung from a concrete


wall that forms a


culvert under I-15.


Figure 3.2-6 shows


details of how the


conduits are hung


from the concrete,


and Figure 3.2-7


shows then entering


the culvert as they


head north and under


I-15. On the


eastern side of I-15


they are again


buried and routed


north along Baldy


Mesa Rd. (an


unimproved dirt road


at this location).


North of Cajon


Junction, as the


X Z / ,.::-7, f si 

z

Figure 3.2-5 Crib Wall Retaining the Southbound Lanes


of I-15 With Fiber Optic Conduits Buried at the Wall


Toe


Figure 3.2-6 Details of Fiber Optic Conduits Supports


on a Concrete Culvert Wall


35

c: I l : A - - - - - -

z±ber OplC1 COnlUlts I 

follow Baldy Mesa


Rd., they cross


under several old


AT&SF, Southern


Pacific, and Union


Pacific railroad


bridges (which are


discussed in Section


3.5 of this report).


After crossing under


the Southern Pacific


railroad bridge the


conduits separate.


Two conduits


containing CONTEL,


MCI, and US Sprint


continue northward


along Baldy Mesa


Road. AT&T and WTG


West conduits turn


east and follow


parallel to the Figure 3.2-7 Fiber Optic Conduits Heading Under I-15,


Southern Pacific Attached to a Concrete Culvert Wall


railroad line along


an unimproved access


road.


After about 2.25 miles the unimproved road (and AT&T and WTG West


conduits) turn north by northeast. The conduits follow this winding road


and approach the north bound section of I-15 about 0.5 miles south of the


first I-15 intersection north of the Cajon Summit (the Caliente and


Mariposa intersection) where they connect with and then follow the route


of Mariposa Road. Mariposa Road runs parallel and east of the northbound


lanes of I-15. As was done on the old Highway 66, whenever there is a


bridge on the Mariposa Road the conduits are placed above ground on the


bridge. Figure 3.2-8 shows a typical conduit routing at a bridge. The


figure shows an additional pipe (believed to be an unidentified water


distribution pipe) hung directly above the conduit.


The CONTEL, MCI, and US Sprint conduits, after separating from the AT&T 

and WTG West conduits, continue to follow Baldy Mesa Road. The cross under


the north bound lanes of I-15 next to the location where two petroleum


products pipelines cross under the highway. They then separate from the


products pipelines and continue north until they approach the south bound


lanes of I-15. Again, they combine with the petroleum products pipelines


to cross under I-15. Thereafter, they continue within the petroleum


products pipeline rights-of-way. This route also places them (and the


petroleum products pipelines) parallel and near to the Los Angeles


Department of Water and Power's two high voltage transmission lines. When


the power transmission lines join with Baldy Mesa Road the conduits (and


the petroleum products pipelines) are routed along the road next to and


36

. . I . between tne two


power transmission


lines. After about


2 miles, Baldy Mesa


Road turns due north


and leaves the power


transmission lines.


The fiber optic


cables and the


pipelines continue


along Baldy Mesa


Road. About 1.5


miles further north


they are joined by a


36-inch natural gas


transmission line,


and all of these


lifelines continue


along Baldy Mesa


Road until they


leave the study


area. It is


instructive, Figure 3.2-8 A Fiber Optic Conduit Hung From a Bridge


however, to examine With a Water Distribution Pipe Directly Above It


how the cables and


pipelines cross over


the California Aqueduct (about another 2 miles north of the study northern


boundary. All of the lifelines are brought to the surface to cross the


aqueduct. One fiber optic cable conduit is hung from the side of the


bridge with light fasteners as was done on other bridges. The other


conduit is hung under the bridge. The petroleum products pipelines also


are hung from the bottom of the bridge while the natural gas pipeline


separately spans the aqueduct (see Section 3.4 for photographs of how


these fuel pipeline lifelines cross the aqueduct).


3.2.2 Microwave and Radio Towers


Because of their remote locations and the need to use trucks with winches


in order to assure travel to their sites, the radio and microwave towers


that support regional communications were not examined during the site


visits. The cellular phone and radio towers which are used by CALTRANS


and PAC TEL for local communications within the Cajon Canyon Pass itself


were examined during the site visits. Refer to the map of Figure 3.2-1


for the following discussions.


Starting from the southern boundary of the Cajon Pass study region, a


radio tower is located at the western edge of the study boundary about two


miles west of the Los Angeles Department of Water & Power's high voltage


transmission lines and about 2.5 miles north of the southern edge of the


study boundary. It is serviced by an unpaved road and distribution


electric power lines. Plans call for the expansion of this site into a


much larger communications center. At that time the collocation of the


37

communications equipment with the


electric and telephone service may


create some at-risk siting


conditions. However, for the


present study it is an isolated


communications facility.


East of Interstate I-15 and about


4.5 miles east of the western edge


of the study boundary and 6.3 miles


north of the southern edge of the


study boundary is a microwave tower


(it is sited near the Cajon


Mountain Lookout station). Access


to this remote site is by unpaved


roads from the Silverwood Lake


State Recreation Area, which is to


the east of the study area. This


tower is part of the regional


telephone communications system,


but its isolated site means that it


does not cause impacts due to


collocation of lifelines.


The cellular phone antenna is


located behind a motel at the Cajon


Junction for highways I-15 and 138.


Figure 3.2-9 is a photograph of the


tower. It is located near to a


motel and a large motel water


storaae tank (which isn't shown in


the figure). Seismic design Figure 3.2-9 Cajon Junction Cellular


criteria were not specified for the Phone Antenna


cellular phone antenna or the water


storage tank. The tower provides


for stationary and mobile cellular phone communications within the Cajon


Canyon area, which otherwise would be in a dead band area for such


communications.


At the Cajon Summit located between the north and south bound sections of


I-15 (about 11.7 miles north of the southern edge of the study boundary


and 3.5 miles east of the western edge of the study boundary) there are


two communication towers. One tower provides for microwave telephone


communications on the AT&T system. It is aligned with other microwave


towers outside the study boundaries, and it connects the high desert


region with the Los Angeles Basin microwave systems. The second tower is


used by CALTRANS 3 ,22) to provide a communications link between the


maintenance facility and radios installed in their service vehicles. It


allows the Cajon Junction maintenance station to communicate both


southward through the Cajon Canyon and northward to regions below the


Cajon Summit (without the tower the summit would shadow the northern


regions from a communications viewpoint).


38

Bibliography for Section 3.2

3.2-1 Source of information: discussions with US Sprint, discussions

and construction drawings and routing maps from AT&T, CONTEL,

and discussions with and routing maps from the US Forest

Service.

3.2-2 Source of information: discussions with the CALTRANS staff at

the maintenance station at Cajon Junction.

3.3 ELECTRICAL POWER LIFELINES

The electric power lifelines. (See Figure 3.3-1) located in the Cajon Pass

study area include a hydroelectric power generation station, high voltage

transmission lines, a transmission system substation, and wood pole

distribution lines and transformers. For reference purposes, the

locations of the photographs provided in this, Section are shown on the

Figure. In accordance with the basis for this study, only the facilities

that relate to regional or bulk transfer of electrical energy are being

examined. Thus, the distribution systems are not described.

Some of the electric power towers have two circuits of three wires each

and some have one circuit of three wires. In conversation, the circuits

are often referred to as "lines". Multiple circuits on a single tower

save right-of-way acquisition and construction costs, but the towers are

larger and cost more. Wind loading criteria generally control the tower

designs. Specific earthquake design criteria usually are not applied.

However, operating experience throughout the industry has confirmed that

towers so designed will perform well under earthquake conditions.

The maps of the U.S. Geological Survey were used as a starting point to

locate the appropriate electrical power lifelines. An initial site survey

confirmed that not all of the transmission lines were identified on the

maps. Subsequent meetings with the lifeline owners were held to gather

detailed information, and that information was validated by additional

site visits, meetings with regulators, and examination of the right-of-way

files of the U.S. Forest Service.

The City of Los Angeles Department of Water and Power is self-regulating

with respect to applying, implementing, and inspecting the application of

seismic hazard standards., The California Public Utilities Commission

regulates. the activities for the Southern California Edison Company

facilities in the Cajon Pass. However, their criteria are general and

non-specific in nature, mostly requiring that the consequences of

earthquake events be accounted for in the design, siting, and operation of

the electric lifelines. Consequently, the transmission systems are not

designed to specific seismic standards, but are designed to standards,

including wind loading, which have been accepted as "'being more

restrictive than would be seismic standards alone"'.

3.3.1 Los Angeles Department of Water & Power Facilities

The Los Angeles Department of Water and Power owns two 287.5 kV

39

3.2.3
20 35

Figure 3.3.1 Map of the Electric Power Lifelines

SCALE 0 I E 2 

EXPLANATI ON

LargerScale Figure

Located at

End of Document

a -

- __ __-_ -

-- - - W-----...-... -

117 21

a

FIG. 4,5

I17? 117 a

INTZX7TS

PAV25 MGMIAY

rot A4

40

xl
transmissions lines that pass through the study area. They were installed


in 1936 to transmit power from the Hover Dam hydroelectric project in


Nevada. At that time they were the highest voltage, long distance


transmission lines in the world. Although seismic design criteria were


not explicitly considered, the transmission system was at the leading edge


of technology at that time, and it was conservatively designed. It has


performed well except for some local impacts due to soil flow, landslides,


and brush fires. The conductor is an air insulated, hollow, segmented


copper cable. The system is considered by the Department to be more than


adequately designed when compared to current Department design standards.


Today, these lines can transmit up to about 600 MW of power. They


transmitted 95% of the City of Los Angeles' power supply when they were


built, they now transmit about 5% of the City's power needs. However they


are also important in assisting in voltage control and in maintaining


transmission system reliability.


North of the study area the transmission lines are connected to the


Victorville Substation, south of the study area they are connected to the


Century Substation in Los Angeles. Originally completed in 1936, the


Victorville Substation has been updated in 1970, 1974, and 1980 to add


switching capabilities between the 287.5 and 500 kV lines as well as other


system controls. Seismic criteria have increased over this time period,


and the 1985 Adelanto converter and switching station (which permits


switching to and from the Victorville station) included subjecting full-


scale equipment to shaker table tests before accepting the equipment.


Figure 3.3-1 shows
 ,;_... - r 

tne route or tne


transmission lines.


Starting from the


southwest border of


the study area, the


transmission lines


move northeast along


the foothills of the


National Forest.


The two transmission


lines are routed


parallel throughout


the study area. An


access road is


provided along the


route. In this


region, prior brush


fires have annealed


the copper conductor


cables causing them


to sag. Repairs


nave restored tneir 

ground clearance. Figure 3.3-2 A View of Power Lines and Buried Fuel
 _, _ _ _ _ . _ . . _
 At the edge of the Pipelines Crossing the San Andreas Fault Zone


41

foothills and the Lytle Creek Wash they turn north by northeast and are


routed in the steep portions of the west side of Lytle Creek Canyon. The


October 1990 and August 1991 brush fires in Lytle Creek annealed parts of


these lines, causing them to sag. The repairs are implemented by


retensioning and replacement/retensioning, as appropriate.


Just south of the Lytle Creek Ranger Station the lines turn north and


cross Lytle Creek Canyon. They are routed through steep, difficult to


access terrain. It was reported that there have been rain-induced


landslides in this area that have impacted towers, necessitating repairs.


These locations were not observed during the site visits. The lines turn


lightly north east and descend down from the higher mountains to the Cajon


Canyon floor near Blue Cut. There they also pass near the railroad lines.


They continue north by north west across the Lone Pine Canyon, which also


contains the San Andreas Rift Zone. They cross the Rift Zone in a north


west direction, ind cating that fault movement can be expected to add


slack to the lines rossing the


I - . . I .

- . . I .- __ . . . - - . . - . . ­ - ___ % _- ---- --- -- - - - -2 -- ­

lateral fault). figure .3-2 snows


the power lines where they cross


the San Andreas Fault. They are


located above and close to a 36­


inch buried natural gas pipeline


and the 8-inch and 14-inch


petroleum products pipelines (they


actually cross over the petroleum


products pipelines and are roughly


parallel to the path of the natural


gas pipeline). Figure 3.3-3 is a


photograph taken in the opposite


direction to Figure 3.3-2. It


shows that the power tower


immediately before the intersection


of the power lines and the fuel


pipelines is located at the edge of


a steep ravine. Also, the tower


shown is typical of the design used


at Cajon Pass.


About 0.75 miles south and west of


Cajon Junction the lines cross over


a small bowl. This region


experienced slow ground sliding


towards the center of the bowl.


Over 15-20 years the movement was


enough to put slack into lines


within the bowl and tension on the


lines lust outside the bowl. The


Department has reset the towers and


placed soil-concrete mixtures and Figure 3.3-3 Power Towers At The Edge


drains on the bowl surface. It Of A Steep Ravine Near The San Andreas


appears that by moving surface Fault Zone


42

waters out of the bowl the slow sliding has been arrested. However,

during an earthquake liquefaction or ground sliding might occur in this

region.

The lines cross the railroad tracks south of Highway 138 and west of I-15

near the Cajon Junction. Next they continue north by northwest, turn

northeast, and again cross the railroad tracks. They then approach

parallel to the south bound route of I-15 (just south of where I-15

divides into widely separated north and south bound segments).

Thereafter, they continue north parallel to the southbound segment of I-15

and the petroleum products pipelines. When I-15 turns, east the

transmission lines turn northeast and connect with the general route of

Baldy Mesa Road. The terrain is very steep as they move up the Baldy

Mountain slope, and surface erosion is a continuing problem.. In this area

and along the Baldy Mesa Road the power transmissions lines are parallel

to petroleum products and fiber optic lifelines. After the Cajon Summit

the power lines proceed northeast and continue in a straight path until

they leave the study area. In this downslope side of the high desert

region they also cross under two 500 kV Southern California Edison power

lines and over the Southern Pacific Railroad line.

3.3.2 Southern California Edison Company Facilities

Figure 3.3-1 also shows the location of the Southern California Edison

(SCE) electric power lifeline facilities. This includes a hydroelectric

power generation station in Lytle Creek, a major Substation (Lugo

Substation) in the northeast portion of the study area, and a number of

high voltage power lines. Three 500 kV transmission lines (the Lugo:MiraLoma lines) run north-south through the Cajon Pass, a short segment of the

Arrowhead:Calectric Shannin 115 kV line passes through the southeast

section of the study area in the Devore-San Bernardino area, and two

Lugo:Vincent 500 kV transmission lines pass from east to west through the

northern half of the study area (north of the Cajon Summit in the high

desert region). The high voltage transmission lines are air insulated

aluminum lines with a steel core that provides the needed tensile

strength.

The Lytle Creek Hydroelectric power generation station (located about two

miles north of the study southern boundary) uses the surface runoff of

Lytle Creek for its water supply. There is some capability to pump from

deep wells to add water flow to this station, if needed. The station was

built in 1904 and has operated since then. It directs the Lytle Creek

through a 3,092 foot channel to the buried penstocks. From there, the

water is directed underground in a piping system through the Lytle Creek

Wash to a second hydroelectric station at Fontana jiast outside the

southern boundary of the study area. Afterwards the water is treated and

distributed to local water districts for their subsequent use. The Lytle

Creek substation is rated at 680 kW, but in 1989 it generated at an

average daily power level of just under 300 kW. Its output is transmitted

at 12 kV on a wood pole distribution system.

The Lugo Substation is located at the eastern edge of the study boundary

43
=-A A a -4 1 -- I I 6AAI ft . D saU. . = 

south of the


northern boundary.


It is just south of


the City of


Hesperia. It is a


major lifeline


facility, it handles


over 2,500 M of


power, and it


provides 

interconnections and


switching between


five 500 kV SCE


transmission lines


and a 500 kV Los


Angeles Department


of Water and Power


line (that line's


connection to City


ownership is north


and outside of the


study boundaries). Figure 3.3-4 Lugo Substation Control Facilities and


Figure 3.3-4 shows Equipment


the administrative


and control


facilities housed a brick building, the communications microwave tower


that provides SCE


with secure.


direct,


communications link


with the


substation, and some


of the station


equipment. Most of


the facility was


designed for a 0.2g


horizontal load.


Figure 3.3-5 shows


the circuit breakers


in more detail.


After the 1971 San


Fernando earthquake


the circuit breakers


were retrofit with


earthquake resistant


bases and their


clamp anchorage was


welded to their skid


frames for more


positive anchorage.


The transformers Figure 3.3-5 Lugo Substation Circuit Breakers


44

have also had their anchorage improved with welding and clamping to their


skids. Recent purchases for the station have been designed against a 0.5g


dynamic evaluation criteria. Although SCE recognizes that the station is


still subject to equipment failures during an earthquake, they have


extensive plans for mitigating the impact of such an event (e.g., managing


the risk of failure). For example, they have alternative plans that could


keep the substation on line under emergency conditions using as few as


about 10% of the circuit breakers.


Starting from the southern boundary of the study area, SCE has three 500


kV transmission lines that connect the Lugo and Mira-Loma substations.


Two of the lines were installed in the early 1960s for about 300 kV


service. They were upgraded to 500 kV service in the early 1970s, and the


third line was added in 1983. A single tower system brings the lines


north by northeast to the study boundary. The original two lines split


into separate tower systems just inside the study boundary. Just outside


the study boundary the new line separates from the single tower system and


heads due east. It turns north at


the Lytle Creek Wash and rejoins ,


the most eastern of the two


original lines. The western line


heads approximately due north


crossing the railroads (several


times) and the old Cajon Pass


highway near Blue Cut. North of


Blue Cut it is rejoined by the


second original line and both head


due north.


The new transmission line joins the


most eastern of the original lines


in a parallel tower system just


north of the southern boundary of


the study area at the mouth of


Lytle Creek. Together they head up


the steep slopes of the lower Lytle


Creek Ridge and then descend to the


floor of Cajon Pass. In the 1970s


there was a landslide on the slope


just before where they reach the


Cajon Pass floor. It damaged the


towers and they had to be repaired.


Figure 3.1-5 shows the landslide


scar and the towers that were


rebuilt on the scar.


After the landslide area, the two


lines cross over the Cajon Canyon


and run approximately parallel to


the west side of I-15. Figure 3.3-


6 shows typical tower footings. Figure 3.3-7 Typical Electric


SCE reported that mostly bell Transmission Tower Footings


45

foundations are used, and if they can't be formed then deep column

footings are used. At Blue Cut the new line separates from the older

original line while the older line continues northwest until it joins the

other original line. The new line crosses over the railroads and Highway

I-15 about 2 miles north of where it separated from the original line. It

then travels on the east side of I-15 by itself until it joins the eastern

most of the original lines north of the railroad summit and north of

highway 138. All of the power lines cross the San Andreas Rift Zone just north of Blue Cut. Fault movements should put slack into the lines that 

bridge the fault. 

After they rejoin just north of Blue Cut, the two original lines travel

north for about two miles. This takes them back into steep terrain. Just

before they redescend to the Cajon Pass floor about 0.5 mile south of

Cajon Junction, they approach the railroads, petroleum pipelines, fiber

optic lines, and highway I-15. It is noted that just before the location

where the towers descend in this region there was some surface erosion or

displacement near the tower foundations. SCE has protected those towers

by covering the ground surface with a soil-cement to seal the surface

material.

The original power lines proceed northeast but are more widely separated

than they were in the southern section of the study area. All three of

the lines come together at the Lugo Substation. Then they continue

northeast and leave the study area.

Another set of two, SCE, 500 kV, power transmission lines (the LugoVincent line) leave the Lugo Substation heading northwest, then they turn

due west. Since they are onf the north side of the Cajon Summit they are

in relatively flat terrain. About 1.25 miles after they cross I-15 they

turn northwest and leave the study area. They are connected to the

Vincent Substation to the northwest.

The third SCE transmission system is the 115 kV line that enters and exits

the study area in the Devore region. This lifeline was not examined in

detail, but it is interesting to note that in November 1990 a high wind

caused a power line in the foothills behind Devore to break. The downed

line ignited a brush fire which burned about 200 acres, destroyed four

homes, and damaged others. The towers, however, were not damaged by the wind. That incident points out that the danger to transmission lifelines

is not just a tower failure, but also a line break.

3.3.3 Bibliography For Section 3.3

No reports were used for this section of the report, the information was

obtained during direct discussions with the lifeline owners.

3.4 FUEL TRANSPORTATION LIFELINES

The fuel pipeline lifelines (see Figure 3.4-1) in the Cajon Pass study

area include two high pressure petroleum products transmission lines, two

high pressure natural gas transmission lines, and an intermediate pressure

46
FI G. 5.6,7, St

17U Sc

Figure 3.4-1

SCALE a 1 fl f

: ! _ w ntsz

AL

Map of the Fuel Pipeline Lifelines.

44

ILANATION

1:L7 a

LargerScale Figure

Located at

End ofDocument

-~ 1-15 

G ---- a -

0 0 0

DLm=A

PAT= ENVAT

nnanm punur nemn

)C IhU&L CM PU DcS

TALTfl

47

*: }

11
natural gas distribution line. For reference purposes, the locations of

the photographs provided in this Section are shown on the Figure. Also

included are a number of valve stations in each pipeline system.

Responsibility for the independent for inspection and safety monitoring

(including accounting for seismic safety) these lifelines lies with the

U.S. Department of Transportation Office of Pipeline Safety. They, in

turn, have delegated their authority for petroleum products pipelines to

the California Office of the Fire Marshal, and for natural gas pipelines

to the California Public Utilities Commission. The Office of Pipeline

Safety's seismic hazards mitigation requirements are very broadly stated

in such terms as "earthquakes should be considered during the design and

installation of such systems". The Office of the Fire Marshal has

retained the broad language in its requirements. The Public Utility

Commission has specific, detailed, seismic design criteria for liquified

natural gas facilities, but the requirement for natural gas pipelines

retains the broadly stated guidelines.

3.4.1 Natural Gas Pipelines

Southern California Gas Co. operates two 36-inch high pressure (about 845

psig) natural gas transmission lines in the Cajon Pass and a 16-inch

intermediate pressure (350 psig) trunk line that delivers natural gas from

the two 36-inch lines to the San Bernardino region (see Figure 3.4-1 which

is a map of the fuel transmissions lines in the study area). A third

north-south gas pipeline (which on the map appears to be an extension of

the more western 36-inch pipeline) is a 36-inch line to the high desert

region. It operates at 936 psig and is connected through a valving

station directly to the two 36-inch high pressure lines. In the study

area, one of the transmission lines is routed on the west side of highway

I-15, the other on the east side. At Cajon Junction the western pipeline

crosses under I-15 and joins the eastern pipeline and the north-south

pipeline at a valving station. There is another valving station near

Devore that connects the two transmission lines and the trunk line.

Piping wall thicknesses are in accordance with the California Public

Utilities Commission General Order No 112-D 3 41). Spacing between the

pipeline valves and separately the pipe wall thickness are controlled by

criteria which in turn are controlled by the population density of the

area. Retrofits requiring more frequent valves and thicker wall pipes can

be required by changes in the population density. Although no changes

have been required in the study area, it appears that business growth

plans near the Cajon Junction and residential population growth in the

high desert region of the study area may require such modifications in the

near future.

The eastern most transmission line (line 4000) was installed in 1966 using

X-60 grade pipe with wall thicknesses ranging from 0.375-0.438 inches.

It operates between the Newberry Compressor station to the north of the

study area and the Fontana pressure limiting station south of the study

area. The western most transmission line (line 4002) was installed in

1960 (it was the original line) using X-52 and X-60 grade pipe with wall

thicknesses ranging from 0.375-0.500 inches. It operates between the

48
Cajon summit valving station north and east of the Cajon Junction and the


Fontana station south of the study area. The north-south line (line 1185) 

was installed in 1976 using X-60 grade pipe and wall thicknesses ranging


from 0.391-0.562 inches. It runs from the Cajon Summit valving station


north to the Adelanto Compressor Station.


Southern California Gas Company operates another 36-inch pipeline that


crosses the San Andreas fault zone north and west of the Cajon Pass. The


three transmission lines (the 1185 and 4002 lines and the 4000 line in the


study area and the third lines west of the study area) supply about 90% of


the Company's natural gas to the Los Angeles Basin. The transmission


lines in the study area presently provide about 750 million cubic feet of


natural gas each day, although their combined total capacity is up to 1


billion cubic feet per day. In addition, the Company maintains natural


gas storage in the coastal area that could provide 30-90 days supply for


its core customers.


Maintenance staff and supplies are


maintained in the Los Angeles Basin


and in Victorville. The emergency


planning assumes that up to 1/2


mile of pipeline on either side of


the San Andreas fault zone could be


failed during a major earthquake.


They maintain prepositioned


material to replace that piping, if


needed, they have written


procedures for responding to such a


requirement, and they have existing


agreements with a helicopter


company to provide helicopters for


their use during such times.


The following discussion tracks the


pipelines from the south of the


study region to the north. This is


counter to the flow direction of


the natural gas, but it is


consistent with the descriptions


provided for the other lifelines.


The 36-inch transmission lines


enter the study area southern


boundary in the Lytle Creek Wash


just west of I-15. They also pass


under the new SCE 500 kV


transmission line where they enter


the study area. Block valves are


used to sectionalize the line.


Just south of the study area is the


Fontana valving station that can be


used to control the pressure in Figure 3.4-2 Natural Gas Pipeline


each line and to cross-connect the Crossings Under Two Railroads


49

- - -- -- -

lines. In the study 

area, they proceed 

east by northeast 

for about two miles. 

At the western edge 

of the Cajon Wash 

there is another 

valving station and 

that is where the 

16-inch trunk line 

to San Bernardino 

takes gas from the 

36-inch lines. The 

36-inch lines then 

turn northeast and 

approximately due 

west of the -15/I215 junction they 

separate. 

The western line 

(line 40021 follows 

*4&c -w-''=Xs' ^>4swWFigure and Atcheson Topeka 

*)�� I - - I - - - 'DM^1 Pi^ 3.4-3 An Exposed Section Of The Natural Gas Pipeline 

& Santa Fe (AT&SF) 

railroad right-ofways to Blue Cut. It crosses the Southern Pacific railroad track several


times, running either parallel and west of the track or in the space


between the tracks of those two railroads. These crossings are buried but


uncased. From Blue Cut the line heads generally north. It runs parallel


and near to the Los Angeles Department of Water and Power's two high


voltage transmission lines for about one mile. In the Lone Pine Canyon it


crosses the San Andreas fault zone very close to two power transmission


lines. It also crosses the two petroleum products pipelines at that


location. This crossing is discussed in more detail in Section 3.3.


Further north (just south of the Cajon Junction) the 36-inch natural gas


pipeline crosses the Southern and the Union Pacific railroad lines.


Figure 3.4-2 shows the pipeline right-of-way descending to and then under


those railways. The crossing under the Southern Pacific is uncased, it is


cased under the Union Pacific. Between Blue Cut and the railroad


crossings south of Cajon Pass there are five sections of exposed line with


spans ranging from 57-118 feet. Figure 3.4-3 shows one of the longer


exposed sections, and Figure 3.4-4 shows a close of up the pipe exiting


the ground. It shows the connection of the pipe corrosion protection


material wrapping (the gray line) as it is connected to the pipe. The


pipe crosses under the AT&SF railroad and I-5 and continues parallel to


the eastern pipeline to the Cajon summit valving station located north of


highway 138. In this route there are two more exposed sections with 68


and 80 foot spans. A recent realignment of Highway 138 brings it very


close to one of the exposed crossings. At that location, the two 36-inch


pipelines are located parallel. The line to the left is exposed, the one


50

to the right is 

buried. 

-�.il . :', !J- �a, I 1 r ;'41' Vml 

When the eastern I 

natural gas pipeline 

(line 4000) I 

separates rom tne 

western one near the 

junction of I-15 and 

I-215 it turns 

northeast and 

crosses under the 

Southern Pacific and 

AT&SF railroads and 

the Cajon Wash. The 

pipeline then runs 

parallel and west of 

the old highway for 

about 0.75 miles, 

then crosses under 

the old highway and 

T-15. When it 

crosses the old highway it also Figure 3.4-4 Details of the Ground Support For Exposed


crosses it also Sections Of Natural Gas Pipelines 

crosses


perpendicular to the


two petroleum products pipelines. This region also has a high water table


and could be subject to liquefaction during an earthquake event.


The 36-inch pipeline continues roughly parallel to I-15 on the eastern


side of I-15. In these steep mountains there have been a number of times


when fires have burned off the vegetation and surface erosion and stream­


bed erosion have occurred, and in the 1970's a landslide after heavy rains


damaged such a portion of this pipeline. Just north and east of the Cajon


Junction the routing turns north by northeast and the pipeline crosses


Highway 138. It runs parallel and north of the highway, and new highway


crossings will result when Highway 138 is rerouted in 1991. Between the


Cajon Junction and the summit valving station there are five separate


locations of exposed pipeline, with the spans ranging from 98-138 feet.


After the valving station, the pipeline (line 4000) turns east and then


northeast and leaves the study area. Twice it crosses the three railroads


in this section. The highway, railroad, and power line crossings are a


mixture of cased and uncased crossings.


The third pipeline (line 1185) is routed north from the Cajon Summit


valving station. It crosses under the railroads next to short railroad


bridges. It continues north, crossing under the northbound and then the


southbound portions of I-15. All of these crossings are cased.


Continuing north, it crosses under power transmission lines and then


connects to and runs parallel to Baldy Mesa Road. It is routed on the


east side of the road, the petroleum products pipelines and three fiber


optic cables are also routed parallel to this road. A valve station is


51 
located on the


shoulder of Baldy


Mesa Rd., and Figure


3.4-5 shows the


posts installed


around the valves to


protect them from a


vehicle accidently


crashing into them.


North of the study


boundary it crosses


the California


Aqueduct. Figure


3.4-6 shows that


crossing.


Figure 3.4-5 Natural Gas Pipeline Valve Station On


Baldy Mesa Road


� ��V Pi 

"I 

Figure 3.4-6 The Natural Gas Pipeline Crossing the


California Aqueduct


52

3.4.2 Liquid Fuel Pipelines

There are two petroleum products pipelines operated by CALNEV Pipe Line

Company in the study area. Figure 3.4-1 shows the routes of these

lifelines. In 1960 an 8-inch pipeline was installed, in 1969-70 a second

14-inch pipeline was installed, and in 1980 several miles of the 8-inch

line that were installed in the Cajon Wash were rerouted to be parallel to

the 14-inch line located east of the Wash (it was reported13 42 ' that the

8-inch line in Cajon Canyon Wash frequently would be uncovered during the

spring runoff, and that the Forest Service requested and CALNEV concurred

that it would be safer to move the line to a region where water runoff

would be less troublesome). The lines are about 250 miles long and were

installed in accordance with the then current American Petroleum

Institute's standards. Those standards required that reasonable

protection for anticipated and unusual external conditions be included in

the design, but specific earthquake criteria were not identified in the

standards. In California, the Office of the Fire Marshall is responsible

for the inspection and enforcement of the federal and California pipeline

safety standards(3 ,

43 ). For the federal requirements, they are the agent

for the U.S. Department of Transportation Office of Pipeline Safety, who

has statutory safety responsibilities.

The fuel pipelines are buried 3-14 feet deep, depending on their location.

When they cross state highways or railways they are normally cased. When

they cross unpaved roads they may not be cased. They operate at 1060-1690

psig. The pipe outside is coated with coal tar and impressed cathodic

corrosion protection is used, the locations for impressing the required

voltage on the pipeline are at the pipeline terminuses. Check valves and

motorized valves are installed on the pipelines, there is no backup

emergency driver if the electricity fails. However, each motorized valve

can be manually operated. The operations are controlled by computers in

the San Bernardino station, there is 100% redundancy in the computer

controls. Twice a year the company conducts training for emergency

response, they fly over the line route every other week, they drive most

of the line route weekly, and they conduct an annual inspection of the

line route. Extra pipe for emergency repairs is stored at various cities

along the route path. There are pump stations in San Bernardino and

Barstow, CA.

The lines pump about B0,000 barrels (bbl)/day of product. The product

provides about 90% of the Las Vegas area fuel and 100% of the fuel for

three Air Force bases. They have 560,000 bbl of storage at the San

Bernardino terminal (normally this capacity is mostly full), and they have

237,000 bbl of gasoline and 106,000 bbl of diesel storage in Las Vegas,

105,000 bbl of storage in Barstow, and 64,000 bbl of jet fuel storage on

one of the Air Force bases.

As a result of the May 1989 derailment and subsequent pipeline

failure/fire in San Bernardino, the side hinged check valves (which had

failed to close during that accident) were replaced with top hinged check

valves. However, the check valve near the accident site was replaced with

a motorized control valve. In early 1990 another train derailment in

53
which the engine and cars came to rest over the pipeline occurred in Las


Vegas. It was reported(
3 -44 that as was the case in San Bernardino, the


derailment itself did not rupture the pipeline. A 100% pipeline


excavation and inspection at Las Vegas indicated that the pipeline was not


damaged by the derailment. In 1988-89 when the fiber optic cables were


installed in the pipeline right-of-way, it was reported 3 4-4 that on at


least two occasions the trencher struck the pipeline, requiring piping


repairs (the location of these incidents was not identified).


The 8-inch pipeline enters the study area on the western side of the Cajon


Wash. Just south of the study area there is a check valve (located east


of the San Bernardino County Prison Farm). The pipeline runs north along


the western edge and within the Cajon Wash. Just after it passes under


Devore Road there is another check valve. It continues in a north west


direction crossing under I-15 before the I-15/I-215 intersection, turns


north and crosses under the Union Pacific, Southern Pacific, and AT&SF


railroads. It then continues for about 1 mile along the eastern edge of


the AT&SF right-of-way. After it crosses the natural gas pipeline it


turns north east, crosses the Cajon Canyon floor and connects with the


existing 14-inch pipeline right-of-way along the old Cajon Canyon highway.


From there it and the 14-inch pipeline are routed in parallel trenches.


The 14-inch pipeline enters the study area in the southeast corner. About 

two miles south of the study area there is a motorized check valve just


north of Duffey St. The 14-inch pipeline follows the Southern Pacific


railroad right-of-way, sometimes crossing under the tracks, most of the


time parallel to and 

outside of the 

tracks. wnen tne 

AT&SF and Southern 

Pacific railroads 

come together south 

of Devore Road, the 

pipeline's route is 

between the tracks 

of the two 

railroads. It 

leaves the railroad 

right-of-ways just 

past Devore Road, 

turns north east and 

crosses under I-15 .Wat the I-15/I-215 I ., 

intersection. It 

continues north east 

and joins the old I I 

Cajon Canyon 

highway. Just as it 

enters under the 

median strip there I , go__ I , ___, - _i' - I I% 

I____'_

is another check Figure 3.4-7 The Petroleum Products Valve Station On


valve. It is joined The Shoulder of Baldy Mesa Rd.


54

by the 8-inch I 1 

pipeline at about 

Kenwood Road. The 

pipelines (and the 

fiber optic 

conduits) follow the 

old highway along a 

northwest route 

until they reach the 

point at Blue Cut 

where the old 

highway makes a 

broad right turn. 

There the pipelines 

turn north for about 

0.5 miles. Both the 

8- and the 14-inch 

lines have check 

valves in this 

region. When the 

route reaches Lone 

Pine Pi.. C-nri rAnunn-. .--.. which I_I_ 

is also the San Figure 3.4-8 Petroleum Products Pipelines Hung Under


Andreas Fault Zone) The Baldy Mesa Rd. Bridge Over the California Aqueduct


they turn left and


follow the canyon


floor for about 3 miles. This was the original route of the 8-inch


pipeline, and the same right-of-way was used when the 14-inch line was


installed. It is parallel to a dirt road. When the road connects with


Lone Pine Canyon Road the pipelines turn northeast. They cross the Lone


Pine Canyon Road several times in cased and uncased crossings. They


continue in their northeast route until they cross under I-15, where they


turn north. Just prior to crossing the railroads, there is another check


valve on the 14-inch line. They follow the general route of Baldy Mesa


Road and cross under I-15 again. In the region between the north and


southbound sections of I-15 there is a check valve on the 8-inch pipeline.


After crossing under the southbound section of I-15 the pipeline turns


northeast and is parallel to the Los Angeles Department of Water and


Power's two 287.5 kV electric power transmission lines. At the summit of


Mt. Baldy there was a pressure reading station. Vandalism has caused


CALNEV to move the gauges to a less prominent location, but the pressure


stems off of the pipelines to the valves are still exposed and it appears


that vandals have been trying to rupture them. When Baldy Mesa Road


separates from the electric power transmission lines the pipelines follow


the road in a northern direction. There they are joined by one of the


natural gas transmission lines, with the pipelines on the western side of


the road and the natural gas pipeline on the eastern side of the road.


About two miles north of the northern boundary of the study area the


pipelines cross the California Aqueduct. Just before the crossing there


is another valve station for each of the pipelines. Figure 3.4-7 shows


the above ground valve station that is on the shoulder of Baldy Mesa Rd..


The barriers were installed to protect the valves from vehicles. At the


55

aqueduct crossings the pipelines are hung exposed under the Baldy Mesa

Road bridge over the aqueduct, and Figure 3.4-8 shows this.

3.4.3 Bibliography for Section 3.4

3.4-1 Public Utilities Commission of the State of California General

Order No. 112-D, "Rules Governing Design, Construction, Testing,

Maintenance and Operation of Utility Gas Gathering, Transmission

and Distribution Piping Systems", November 1988.

3.4-2 Source of information: meetings with the US Forest Service at

the Lytle Creek station.

3.4-3 Source of information: meetings with the US Office of Pipeline

Safety and separately with the California Office of the Fire

Marshall, Pipeline Safety Division.

3.4-4 Source of information: conversations with CALNEV Pipeline

Company.

3.5 TRANSPORTATION LIFELINES

The Cajon pass has served as a route for passage of people and goods

between the Los Angeles basin and the high desert region from earliest

times, since it is the only relatively easy penetration of the San Gabriel

and San Bernardino mountains. One of the old main transcontinental

highways, Route 66, used this route, as did the Atcheson, Topeka and Santa

Fe (Santa Fe) railroad. At the present time, the old Route 66 has been

replaced by Interstate Highway 15 (I-15) with a spur into San Bernardino

(I-215), and Route 66 in the southern portion of the Cajon Pass has since

become a county road restricted to two lane, opposing traffic. A primary

State highway, Route 138, runs east-west from the Silverwood and Arrowhead

Lake recreation areas in the east to Palmdale in the northwest. Route 138

intersects with I-15 at Cajon Junction. There are also three mainline

railroads in the study area: the Santa Fe, the Union Pacific, and the

Southern Pacific. Under emergency conditions it might be possible to

route all railroad traffic on one rail line because their close proximity

could facilitate making such connections. However, this possibility was

not examined during the present study. Figure 3.5-1 shows the

transportation lifeline routes in the study area. For reference purposes,

the locations of the photographs provided in this Section are also shown

on the Figure.

3.5.1 Highways

The interstate highway through the Cajon Pass was originally completed in

the era of 1965-1969. It follows the old alignment of Route 66, except

for the section through the steeper part of the route in the pass itself,

where the new interstate highway is laid on an improved alignment which

begins its climb earlier and yields lesser grades and more gentle curves.

It also increased the traffic capacity, with up to four lanes in each

direction in the sections with greatest grades. The traffic on I-15 has

56
To~~~~~~~F

FIG. 13

4 Fl4t FIG.1

44 f

. -

Figure 3.5-1

SCALZ

ia _I a U"

.. wwn A d

2U

Map of the Transportation Lifelines

E=LANATION

-~ 1-L

-I 

DrT Ia

PA~T IOzm&57

57

*vi

117 z2

LargerScale Figure

Located at

End ofDocument
increased over recent years, with the average daily traffic now

approaching 60,000 vehicles/day in the section below Cajon Junction. On

weekdays, this traffic includes about 28% large trucks.

In 1975, a new interstate section was completed connecting the area near

Devore at the south end of the Pass directly with I-10 near Ontario, thus

bypassing the city of San Bernardino for traffic bound for the Los Angeles

area farther west. The existing I-15 section from Devore to San

Bernardino was redesignated as I-215.

The highway lifelines would be of major value to the immediate recovery

phase after an earthquake or other disaster, since they provide access to

the area from supporting communities to the north. Also, they provide a

vital link to the several military airfields in the high desert area which

are likely to be less affected than the airports in the Los Angeles-San

Bernardino corridor.

Damage to the highway lifelines may result from several aspects of the

earthquake. The bridges are vulnerable to forces generated by ground

shaking. The roadway itself may be interrupted by landslides coming down

onto the roadway or by the failure of man-made fill sections. There are

also some areas where there is a potential for liquefaction of the ground,

with loss of both structures and embankments: for example, at the Cajon

Wash at the southerly entrance to the Pass just south of the I-15/I-215

intersection, and separately, just north of that intersection; near Blue

Cut; and at the alluvial deposits in Cajon-Creek just south of the

junction of I-15 and Route 138. The highways cross the San Andreas fault

trace, and the traces of other numerous faults in the area. In those

locations there is the potential for direct shearing ground displacements.

There is also a significant possibility for interaction with other

lifelines, since the highways cross over or pass under major rail lines at

ten points, cross over natural gas and petroleum products pipelines and

communications lines at numerous points, and cross under the high voltage

power transmission lines, as discussed in previous sections of this

report.

The main highways operated by the California Department of Transportation

(CALTRANS) include 55 bridges in the study area. CALTRANS has been

evaluating all of the thousands of highway bridges under its jurisdiction

for earthquake vulnerability, using a special screening

technique .51,3.52, 353) for the first level evaluation in order to identify

the most hazardous in proper priority for their retrofit program. This

screening work has been completed on 28 of the 55 bridges in the study

area as of the fall of 1990. For the 28, there has1 been a tentative

decision to retrofit or replace 12, leave 13 as is, and hold 3 for further

consideration. Screening of the remaining 27 is in process.

Fortunately many of the bridges could be easily bypassed for limited

emergency traffic. Most of the interchanges on I-15 are of the "diamond"

type, so that if the main route bridge is damaged, limited traffic could

be routed on the existing ramps down to and across the intersecting

roadway, and then back up onto the Interstate. There are some cases where

58
this will not be


possible, such as at


the longer bridges


and separation


structures at the I-


15/I-215 junction at


Devore. There are


some local roads in


the area which also


could be used for


bypass, and there is


a long section of


old Highway Route 66


which has been


partially abandoned


and which parallels


the lower southbound


section of I-15 for


about 7 miles from


Devore to just south


of Cajon Junction.


This old fanilitv


was a four lane Figure 3.5-2 I-15 Bridge Over Lytle Creek Wash


divided highway, but


now only the west


roadway is in service. Unfortunately, sections of this roadway are, no


doubt, more vulnerable to earthquake damage than is the new Interstate,


especially at Blue


Cut, where it passes 


over trace of the


San Andreas fault.


It should be noted


that the bridges on


this old alignment


carry conduits for a


number of fiber


optic communication


lifelines, and the


two petroleum


product pipeline


lifelines are


located in the


center median of the


alignment. Because


of the semi-desert


climate of the


region, it may also


be possible to route


some detour traffic


across open off-


highway areas, II


especially in the Figure 3.5-3 I-15 Bridge Over Cajon Creek Wash


59

northern portions of the study area.


CALTRANS has a District Maintenance Station just west of the Cajon


Junction interchange off of Route 138. Considerable construction


equipment and some limited supplies of repair materials are stored there.


There is a small commercial sand and gravel operation in the Cajon


Junction area. The maintain a radio transmission tower near the highway


summit to aid in radio communication with their transportation equipment


operators.


Interstate Highway 15 (I-15) enters the study area from the southwest as


two four lane separate roadways near Nealyes Corner, where it crosses


Sierra Avenue just west of Lytle Creek Wash. The pavement is concrete.


There is a grade separation structure for each of the I-15 roadways


(Bridges No.54-0891R and L), consisting of cast in place pre-stressed


concrete girders. The highway continues northeast on a long viaduct of


concrete box girders, each continuous over several spans (Bridge


No.54-0982R and L), crossing Lytle Creek Wash and the San Jacinto fault


zone in this area (see Figure 3.5-2). It then ascends the west slope of


Lytle Creek Ridge across Sycamore Flats, crossing over Devore Road just


west of the ridge on a concrete box girder (Bridge No. 54-0779R and L).


It then descends and crosses Glen Helen Road on Bridge No. 54-0780R and L,


and the rights-of-way of the Southern Pacific, the Union Pacific, and the


Santa Fe railroads on Bridge No. 54-0818R and L. It then crosses the


Cajon Wash on a set of continuous concrete box girder structures


designated as Bridge No. 54-0781 (see Figure 3.5-3), which carries the


north and southbound main roadways, the west-south connector, and the


east-south connector


eA ' 4t - i c .L WCdWy= 

-- A--r _ . AL. Ll 

point, I-15 joins


I-215 coming up from


the southeast from


San Bernardino at a


complex set of
 - -: . _ _ separaLI..ou 

structures (Bridge


Nos. 54-0782, -0783,


and -0771). All of


these bridges are


constructed from


prestressed


concrete. The


taller separation


structures are


supported on


multiple column


bents.


On the section of


I-215 coming up from


San Bernardino,


which enters the Figure 3.5-4 I-15 Bridge Over Kenwood Avenue


60

1 

study area at


Verdemont, there are


three concrete box


girder bridges on


the main three lane


roadways, which are


at Palm Avenue,


Cypress Avenue, and


Devore Road (Bridge


Nos. 54-0532,


54-05433, and


54-0525), and one


prestressed concrete


structure on the


east-south


connection and


collector roadway at


Devore (Bridge No.


54-0844).


As the I-15 highway


LsLJniL±IILLeS cIJ L LI. JLU 

its junction wit Figure 3.5-5 I-15 Arch Bridge Over Matthews Rd.


I-215, it is two


independent roadways


of four lanes each, concrete paved. It passes over Kenwood Avenue on a


continuous box girder (Bridge No. 54-0772), with a typical diamond type


interchange. Kenwood Avenue connects with the old alignment of Route 66


about 0.2 miles further west (see Figure 3.5-4).


I-15 continues over Matthew Road with a 21 ft. span, multiplate arch


(Bridge No. 54-0915, Figure 3.5-5). I-15 then passes through a steep cut


about 1.5 miles north of this point, and on the north side of the ridge


swings to the east away from the old alignment. Both the old and the new


alignment cross the trace of the San Andreas fault in this vicinity. At


mile 18.48, I-15 crosses Cleghorn Creek on another concrete box girder


(Bridge No.54-0773) just east of the settlement of Cosy Dell, north of


which it again runs parallel with the old alignment for 1.5 miles but at a


higher elevation. It crosses debris-filled Cone Creek at mile 19.29 on a


prestressed concrete structure (Bridge No. 54-0774), Brush Creek on a


concrete box girder (Bridge No. 54-0775), and then Cleghorn Road at mile


20.0 on another concrete box girder (Bridge No. 54-0776). This is another


diamond type interchange with connections to Cleghorn Road, the old


alignment of Route 66, the settlement of Cajon, and the railroads to the


west of the highway.


Just south of Cajon Junction, I-15 spreads out to accommodate north and


southbound truck weighing stations. The roadway is on a moderately high


fill, supported on the west side by a metal crib retaining wall


approximately 18 feet high (see Figure 3.2-5). The East Fork of Cajon


Creek passes under this fill through a large concrete box culvert


designated as Bridge No. 54-0777. This structure is on a curved


61

alignment and is 39


feet wide and 15


feet high, with a


length of 440 feet
 : a~I along the center


line. As noted in


Section 3.2.1 above,


four communications


conduits are


attached high on the


east wall of the


culvert waterway


(see Figure 3.2-7).


The outlet end of


the culvert directs


the creek flows


into the railroad


bridges of the Sante


Fe and Union


Pacific. The ground


water is close to or


at- +-he surf a in 

this entire region, Figure 3.5-6 I-15 Box Bridge Over the Railroad


and lush plant


growth indicates


that the high water table extend at least to the foot of the metal


retaining wall crib.


Approximately 0.7 miles northwest of the weighing station, I-15 passes


under Route 138, which is carried on a two span, welded steel girder with


a central pier located in the median of I-15). There are steep slopes


just to the east of this junction, and construction is underway on the


realignment of Route 138 to the east. From this point, I-15 climbs


steeply toward Cajon Summit, crossing the Union Pacific at mile 22.0, the


Sante Fe at mile 23.7, and the Southern Pacific at mile 22.7 at Alray.


These crossing structures are all tunnel-like box structures (see Figure


3.5-6), with lengths from 250 to 300 feet, crossing the highway fill at a


skew. Beyond the last of these rail crossings, the northbound and


southbound roadways of I-15 separate. The northbound lanes swing to the


east sooner than the southbound and run along the steep slopes at an


elevation about 200 feet lower and on an alignment about one thousand feet


south of the southbound roadway. The petroleum products pipelines and


some of the fiber optic communication lifelines pass under the highways in


this region. Also, an unimproved road used for access to those lifelines


(the Baldy Mesa Road) crosses under I-15 in cement'culverts. The


northbound roadway of I-15 climbs to rejoin the southbound roadway at the


Oak Hill Road interchange at mile 28.7. This interchange structure


(Bridge No. 54-0740) is a steel girder which provides for connections with


local roads and the service roadways which parallel I-15 from this point


to the north in the relatively flat high desert land.


At mile 31.1, I-15 again crosses the tracks of the Southern Pacific at


62

Bridge No. 54-0664,


a continuous slab


structure supported


on multiple column


bents (see Figure


3.5-7). This bridge


is flanked by others


which carry the


service roads over


the railroad, the


easterly bridge has


water pipelines and


fiber optic


communication


conduits attached


(see Figure 3.2-8).


There is a grade


separation structure


of welded steel


girders (Bridge No.


54-0665) at mile


31.8 which connects


the northbound lanes


of I-15 to the


northbound lanes of


I-395 leading north


to Adelanto, and 0.5


in each direction,


is crossed by Phelan


Road on a concrete


box girder (Bridge 

No. 54-0624). Just


at the north end of


the study area, I-15


and both frontage


roads are carried


over the California


aqueduct on a double


box, concrete


culvert (Bridge No.


54-0828). I-15


continues northeast


out of the study


area towards


Victorville and


Barstow.


Route 138 enters the


study area from the


west, joining the I­


15 at Cajon


Junction.


Approximately one


Figure 3.5-7 I-15 and Access Road Bridges Over the


Railroad


miles further north, I-15, now reduced to three lanes


: $ it Do $ it [S;lt:ff0 SS if 50 in tS, :::;Ei? 

Figure 3.5-8 Highway 138 Cut & Fll At ajon Junct-1n 

63

mile west of this point, it passes under the Southern Pacific, which is

carried on a steel, through-plate girder (Bridge No. 54-0832), then over

the eastbound and westbound combined tracks of the Sante Fe and Union

Pacific on Bridges No. 54-1056 and -1057 respectively, and then over the

upper reaches of Cajon Creek on Bridge No. 54-0561. It crosses over I-15

on a steel girder structure as indicated above, and then continues along

the south side of steep slopes to the east. This section of Route 138 has

been recently reconstructed to improve its grade and alignment, since it

carries heavy recreational traffic to the Arrowhead and Silverwood Lakes.

The new alignment includes large cut and fills next to I-15 (see Figure

3.5-8). Plans for 1991-92 include extending the realignment for another

2-3 miles to remove the numerous switch backs and their supporting fills.

Observations of a number of those fills indicates that they have settled,

causing surface cracking of the roadway pavement.

3.5.2 Railways

The main lines of the Atcheson, Topeka and Santa Fe (Santa Fe), the

Southern Pacific, and the Union Pacific railways all run through Cajon

Pass in close vicinity to each other. In fact, there is some mutual use

of the right-of-ways, and a short section near Cajon Junction where

interconnection of the Santa Fe and the Union Pacific is possible (but

there is little special construction there). The Santa Fe and Union

Pacific presently jointly use the Union Pacific tracks for eastbound

traffic up the Pass, and the Santa Fe tracks for westbound traffic down

the pass. The rail traffic in the Cajon Pass is about 75 trains per day

and they experience about one minor derailment each year. The traffic

also includes four AMTRAC passenger service runs per day. The Southern

Pacific has major yard operations and repair facilities at their Coulton

Yard in San Bernardino.

At the time of completion of this inventory phase of the project, the

information for the railroad bridges, except for the highway crossings

which were available from the California Department of Transportation,

were incomplete. The railroads were unable to provide detailed

information on their systems for this study.

The officials of the Southern Pacific indicated that it was standard

policy to require all pipeline crossings to be cased, and the field data

and data from the pipeline utilities confirms this. Most of the pipeline

crossings for the Santa Fe and Union Pacific are cased, but not all of

them are.

The Southern Pacific enters from the southeast corner of the study area

from San Bernardino in the vicinity of Verdemont, and runs northwest

parallel to and about 0.2 miles west of Cajon Blvd. along Cajon Wash. The

Union Pacific and Sante Fe enter near the same point, but run, adjoining

each other, on the east side of this same roadway. The 14-inch petroleum

products pipeline is buried in the Santa Fe and Union Pacific right-ofways, and periodically runs on the east side and then in the space between

the railroad beds.

64
Tih cm"M Fn ="A I I 

Union Pacific cross 

over to the west 

side of Cajon Blvd. 

just south of its 

junction with 

Kendell Drive. 

There the track 

expand to a four 

track section about 

1.2 miles long 

ending at Devore. 

This section allows 

the railroads to 

switch back to their 

own tracks after 

they have descended 

the Cajon Pass. 

They then continue 

together with the 

Southern Pacific 

Uv.r rLuygU arus 

Cajon Creek and Figure 3.5-9 Railroad Bridges In Cajon Wash, I-15 

under highway I-15. Bridge In The Background 

Figure 3.5-9 shows 

the railroad bridges 

in the wash area with the I-15 bridge in the background. All three lines


then continue northwest along the west side of Cajon Wash close to the


steep slopes, crossing several culverts and small bridges up to Blue Cut.


While in the region of the steep slopes, one of the 36-inch natural gas


pipelines is buried west of and in the right-of-way of the Southern


Pacific. Occasionally, it crosses under the Southern Pacific and is


buried between the beds of the Southern and Union Pacific railroads.


At Blue Cut the Sante Fe and the Union Pacific are close together on the


west bank of Cajon Creek in the narrow gorge region, while the Southern


Pacific has begun to diverge slightly to the northwest. All three lines


cross Lone Pine Creek and the San Andreas fault zone in this general


vicinity, and then continue northward next to the steep slopes on the west


side of Cajon Canyon to the vicinity of Cajon Junction. Here the Southern


Pacific is on a new alignment which begins the climb to the summit west of


Cosy Dell, and is some 100 feet higher than the other two railroads when


it swings west from Cajon Creek.


The Sante Fe and the Union Pacific cross to the east bank of Cajon Creek


on a steel girder bridge, and have a section about one mile long which is


four tracked in the flat land west of the Cajon community (it allows for


siding a slow train to allow an express to pass, etc.). The Santa Fe and


Union Pacific return to only two tracks, with the eastbound crossing Cajon


creek to the west on a concrete deck structure supported on steel piles


(see Figure 3.5-10) and the westbound a steel girder bridge on rubble


concrete piles (see Figure 3.5-11). In the areas of the bridges of


65

Figures 3.5-10 and


3.5-11, the water


table is high as


indicated by the


lush plant growth in


the figure (also see


Figure 3.2-5).


The railroad then


climbs the hills


west of Cajon


community in a long


"S" curve where it


joins and parallels


the alignment of the


Southern Pacific as


it approaches Route


138 about one mile


west of Cajon


Junction. The


Southern Pacific


track crosses over


Route 138 on a new


steel through girder


with a ballasted


deck (see Figure


3.5-12). This


skewed, single span


bridge potentially


could fail during an


earthquake. From


there the railroads


cross over the upper


reaches of Cajon


Creek on a


multi-span, steel


deck, girder bridge,


and then head


eastward under I-15


at Alray.


The eastbound Sante


Fe and Union Pacific


track passes under


Route 138 about 0.1


mile east of the


Southern Pacific


bridge, then Cajon


Creek on an old,


multispan, steel


deck, girder bridge.


It then parallels


. ^z-.t£ .- ,, - I 

Figure 3.5-10 Concrete Beam Railroad Bridge in Cajon


Creek Near Cajon Junction


Figure 3.5-11 Rubble Pier Railroad Bridge in Cajon


Creek Near Cajon Junction


66

the alignment of the


Southern Pacific,


crossing under I-15


to the east just


about 200 feet short


of that railroad at


Alray. The


westbound track of


the combined Sante


Fe and Union Pacific


crosses to the west


of Cajon Creek just


to the west of the


I-15 truck weighing


station, and


continues northwest


to cross under Route


138 about one half


mile west of Cajon


Junction (see Figure


3.5-13). It then


turrns.east nd


I crosses under Iabout 0.6 mile south 


of the eastbound


track.


After the r~ain" 

Junction (heading


north), all three


rail lines run east,


climbing the grade


to the railroad
 ^, 4 %;aJoLn =U."UUUL ,.;4 &.___ ar. 

the head of


Horsethief Canyon.


The Southern Pacific


and the eastbound


Sante Fe-Union


Pacific are on


improved alignments,


whereas the


westbound Sante


Fe-Union Pacific


still involves a few


short tunnels, which


were constructed in


about 1916, (see


Figure 3.5-14) about
 3- ... __ .I- -A'~ %

Alin M.L.Lfd t-A;5L U1 Aem 

1-15 crossing. In 


this region there 


- ��' I I, -q- '1_ --1.1111�1-'Z' NON,? 

1� 9 

Figure 3.5-12 Ballasted Deck Railroad Bridge Over
 Highway 138


i� 

ii 

I

W 

Figure 3.5-13 Highway 138 Bridge Over Railroad At


Cajon Junction


67

are a number of
 ahnr a hr;-fia Ia I - __ -rat I 

(see Figures 3.5-15 Iw+^


which shows two such


bridges) on all
 f three lines. They 


are used to cross ' I 

unimproved roads and A f i r Tn me fI , 

cases, buried


natural gas and


petroleum products


pipelines and fiber


optic cables are


located under the


embankments next to


the bridges. From


the summit, the


eastbound and


westbound tracks of


the Sante Fe-Union
 nori F4 i o11ri" nn

common alignment in Figure 3.5-14 Railroad Tunnel North of Cajon Junction


a northeasterly


direction toward


Barstow, while the Southern Pacific follows this same direction with a


double track section


-9 - Shn ="aAna 

one half miles, then


a single track for


about one mile.


Afterward, it swings


northwest to pass


.. - 3 A 'T 4-f. _ -, UIIUML LIL L..L _&PL.a L 

I-15 just south of


its junction with I­


395, and then heads


towards Palmdale and


out of the study


area.


0 �'*' 

Figure 3.5-15 Typical Short Span Railroad Bridges


North of Cajon Junction


68

3.5.3 Bibliography for Section 3.5

3.5-1 "Seismic Design Procedures and Specifications 1940 to 19681!

CALTRANS Division of Structures, undated.

3.5-2 B. Maroney and J. Gates, "Seismic Risk Identification &

Prioritization in the CALTRANS Seismic Retrofit Program"1 ,

undated.

3.5-3 "Seismic Risk Algorithm For Bridge Structures", CALTRANS SASA

Division *of Structures, June 1990.

4*0 CONTACTS MADE DURING THE STUDY

The following list identifies the offices, and organizations contacted

during the preparation of this report.

American Telephone & Telegraph, 4430 Rosewood Dr., Pleasanton, CA 94566-

9089

American Petroleum Institute, 1220 L St., Washington DC.

California Department of Conservation, Division of Mines & Geology, 630

Bercut Dr., Sacramento, CA 95814-0189

California Department of Transportation (CALTRANS), 1801 30th St. West

Bldg, Sacramento, CA 95816

California Department of Water Resources Southern District, 849 So.

Broadway, Suite 500, Los Angeles, CA 90055

California Energy Commission, 1516 9th St., Sacramento, CA 95814-5512

California Office of Emergency Services, 2151 East D St., Suite 203A,

Ontario, CA 91764

California Public Utilities Commission, 505 Van Ness Ave, San Francisco,

CA 94102

California Seismic Safety Commission, 19.00 K St. Suite 100, Sacramento, CA

9,5814

California Utility Underground Service, 3030 Saturn, St., Suite 200, Brea,

CA 92621

*CALNEV Pipe Line Co. 412 W. Hospitality Lane, Suite 202, San Bernardino,

CA 92412

Continental Telephone, 16071 Mojave Dr., Victorville, CA 92392

Gas Research Institute, 8600 West Bryn Mawr Ave., Chicago, IL 60631

69
Earthquake Engineering Research Institute, 6431 Fairmount Ave., Suite 7,

El Cerrito, CA 94530

Electric Power Research Institute, 3412 Hillview Ave., Palo Alto, CA 94303

Los Angeles Department of Water & Power, 111 North Hope St., Los Angeles,

CA 90051

MCI, 400 International Parkway, Richardson, TX 75081

National Association of Corrosion Engineers, 1440 South Creek Dr.,

Houston, TX 77084

National Center for Earthquake Engineering Research, Buffalo, NY, 716 636-

3391

Northern Telecom Canada Ltd. 2800 Dixie Rd. Brampton, Ontario, Canada L6V

2M6

San Bernardino Valley Municipal Water District, 1350 So. E St., San

Bernardino, CA 92412-5906

Southern California Edison Company, 2244 Walnut Grove Ave, Rosemead, CA

91770

Southern California Gas Company, 3208 N. Rosemead Blvd., El Monte, CA

91731

State of California Office of State Fire Marshal, Pipeline Safety

Division, 1501 W. Cameron Ave, South Bldg, Suite 250, West Convina, CA

91790.

US Sprint, 521 West Rialto Ave., Rialto, CA 92376

U.S. Department of Transportation, Office of Pipeline Safety, 400 7th St.,

SW, Washington, DC 20590

U.S. Geologic Survey, 345 Middlefield Rd., Menlo Park, CA 94025

U.S. Forest Service, Cajon Ranger District, San Bernardino National

Forest, Star Route Box 100, Fontana, CA 92336-9704

70
APPENDIX A

DETAILS FOR FIGURE 3.1-1, REGIONAL EARTHQUAKE FAULT DATA

71
TABLE 3.1-1 Geologic and seimologic characteristics of late Quaternary faults in the Los Angeles region

(Evidence of faulting age: OS, offset stratigraphy; P,fault-produced physiographic features;

W, ground-water impediment within late Quaternary alluvial deposits. Type of faulting: R, reverse; N. normal; SR, right-lateral strike slip; SL, left-lateral strike slip; RRO, reverse right oblique; RLO, reverse left oblique; NRO, normal right oblique; NLO, normal left oblique)

Type of

Age and evidence late

of latest Quaternary

Map number and fault Geomediic aspects surface faulting offset Seismicity Sources of information

1 San Andreas fault zone------ Numerous subparallel faults of

varied length in zone

generally 0.3-1.5 km wide (as

wide as 4 km near Palmdale

and Lake Hughes). Zone

strikes N. 85'-70- W. but

near Banning strikes N. 40-

W. Most faults are approximately vertical, although SE.

from Cajon Pass generally

dip 55s-80 NE. The most

recently active element

within zone typically composed of linear segments 0.5

to 11 km long arranged in

echelon manner in belt as

wide as 100mo.Scattered

splay faults locally diverge

from trend of main zone.

Subsidiary south-dipping

faults common on southern

side of zone adjacent to

Antelope Valley. Fault zone

extends as continuous surface feature from near Banning NW. more than 1.000

km to Cape Mendocino.

Connected by Banning fault

(951to Indio segment of San

Andreas fault NE. of Im.

perial Valley.

Historical (1857)SE to Wright- SR Source of 1857Fort Tein

wood. Holocene (OS. Pi from

Wrightwood to near Banning. Splay and subsidiary

faults chiefly late Quaternary

(05. P).

earthquake (estimated M

7.9),whose epicenter probably was in the

Parkfield-Cholame area of

central California. Possible

source of July 22, 1899,

earthquake (estimated Mt

6.5I near San Bernardino.

Diffuse belt of scattered

small earthquakes

associated with fault zone.

Mapping. Quail

Lake-Wrightwood:

Barrows and others (19615)

Mapping. Quail

Lake-Palmdale:

Beeby (1979)

Kahle (1979)

Kahle and others 119771

Kahle and Barrows (1980)

Mapping.

Palmdale-Wrightwood:

Barrows and others (1978)

Barrows 11979.1980)

Schubert and Crowell

(1980).

Mapping,

Wrightwood-Banning:

1. C. Matti (unpublished

data. 1983).

Miller (1979)

Morton and Miller 11975)

Ross (1919

Sliptrecurrence:

Davis and Duebendorfer

(1982l,

Rasmussen (1982a)

Rust (19821

Sieh (197aa. c. 19841

Weldon and Sieh (1981)

Seism icity:

Green (19831

Hileman and Hanks (1975)

C. E. Johnson (unpublished

data. 1982).

San Jacinto fault zone

2 Glen Helen-- ingle strand. Strikes

N. 40t-00@ W. Presumed vertical dip. Length at least

8km.

Holocene (P. W) SR

Closely associated small

earthquakes. Geometrically

compatible fault-plane

solutions. Possible source

for Iwo damaging earthquakes of MLe6 (1899.

19071.

Cramer and Harrington

(1984. in press).

Pechmann (in press)

Sharp (1972)

Thatcher and others (1975

as 0.3 km. Strikes N. 40?-0'

NW. Dips 350 NE. to vertical. Length approximately

25 km.

4 Lytle Creek-----------------Single strand. Strikes N. 45'

W. Dips 850SW. Length at

least 12 km.

5 Claremont------------------Single strand composed of

closely overlapping breaks.

Strikes N. 40'-55' W. Dip

vertical or steeply NE.

Length approximately 65 km.

Late Quaternary (OS)

Late Quaternary (OS. W)

Holocene (OS,P. Wb historical

creep near Hemet possibly

related to subsidence due to

ground-water withdrawal.

SR. RRO Numerous small earthquakes

near fault trace.

Ceometrically compatible

fault-plane solutions.

RRO fNumerous small earthquakes

near fault trace.

Geometrically compatible

fault-plane solutions.

SR

Scattered small earthquakes

near fault trace. Possible

source for four damaging

earthquakes of Ml 1

2 

(1890.1899.1918919231.

Cramer and Harrington

(1984.in press(.

C. E. (ohnson (unpublished

data. 19821.

Morton (1975, 1976)

Cramer and Harrington

(1984.in press).

C. E. Johnson (unpublished

data. 19821.

Merger and Weldon (1983)

Morton (1975.19761

Fett 119671

Given (1981)

Green (19831

C. E. Johnson unpublished

data, 1982).

Morton (19781

Sharp (19721

Thatcher and others (1975)

3 San
TABLE 3.1-1 Geologic and seimologic, characteristics of late Quaternary faults in the Los Angeles region -Contiaued

Type of

APe and evidence lato

of latest Quaternary

Map number and fault Gometric aspects surface fauliing offset Seaimicity Sources of informathon

-an jac3t hultmoozne-conmues:

a Eam Loma-------

echelon strands. Strikes N.

35-40P W. Dips 50r-l7

NE. Length approximately

iS [m_

Holocene [OS. P. W) creep

movement sinoc at least

1939. possibly related to subsidance due tD ground-water

withdrawal

N or NRO Scattered small earthquakes

near fault trac

Given (19.1)

Fart (1967)

Morton [1978]

Proctor [192. 1974]

Rasmussen (S1L1.1962b]

C. Ea [hnson [unputabthhd

'data. 19621.

7 Hot Springs--------------Single strand. Strikes east-west

to N. 4s- W. Dips steeply

NE Length approxinataly

29 km.

Probably late Quaternary (P] R or RRO Scattered smali earthquakes

at southern endof fault

trace

a Clark----------------Sintne strand composed of

closely overlapping breaks.

Strikes N. 5s-6c IV. Dips

vertically to 60W NE longth

at least aS km.

Holocene LOS.P) SR and RRO Numerous closely associated

small earthquakes along

northern and southern sacore. eemetrically comnpatible fault-plane solution.

Possible source for ML 5

earthquake in 1937.

Given (1981)

Sanders and Kansamun (1954)

Sharp [1967. 1972. l9E1Sal

Thatcher and others 41975)

9 Rialtaolton ---------------- Two echelon strands.

Strikes N.45--55- W.

Presumed vertical dip.

Totai [englh 26 km.

10, Censtrl AvenUe--------------Presurned single stand.

Strikes N. 35 W.

Dip unknown.

Length at least a ka.

Late Quaternary (Lf no surface expression.

SR Numerous small earthquakes

nearby.

Late Quaternary [nh no surface expression.

California tepartmsent of

Water Resources 419710]

C. E [ohnaon (unputbed

date, 19623

Morton (1976)

Ziony end others [19741

11 China-- ----- -------- Single strandStrikes N 35--55 W.

Dips 60E-455 SW.

Length at Least a km.

12 Whittier-------------------One to three subparalld

strands in zone as wide as

1.2 kn. Strikes

N. tS:e-0 NE. Dips,

65-60 NE Length at least

4D lkm.

Late Quaternary [OS. P. VW

Late Quaternary [OS. P)

NW. of Era Canyonr

Holocene OS] SE to near

Santa Ana River.

PRO Scattered small earthquakes

SW. of fault Irace.

RRO Numerous small earthquakes

closely associated with

fault.

Durham and Yerkes 419641

Heath and others 119621

C. E Johnson [unpublshd

data, 19624

Weber [19SM

Durham and Yerkes 419641

Hainan and Others 419]79

C E Johnson unpublished

data. 19621.

Iremr 41972 1973]

Morton and others [1973]

YBake ([172)

Strikes. N. t-0 5-I W.

Presumed to dip steeply SW.

Length approximately 7 km.

Probably Holocene (f] R or RRO Hart and others, 1979]

Weber [19773

14 Frano-Segla---------- -Single strand. Strikes N.

55-5es WVDips

15--5D- SW. Length at least

16 km.

15 Tin Mine- ---------------Single strand.

Strikes N. so- W.

Vertical dip. Length approximately 5 km.

Given 41961]

Sharp [19671]

Elai re fault zone.

13 Main StreetLate Quaternary [PJ R or RRO

Late Quaternary (P)

Weber (1977)

SR Weber 41977)
TABLE 3.1-1 Geologic and seimologic characteristics of late Quaternary faults in the Los Angeles region-Continued

Type of

- Age and evidence late

of latest Quaternary

Map number and fault Geometric aspects surface faulting offset Seismicity Sources of information

tlainor fault zone-Continued:

1B Glen Ivy North--------------Single strand of closely over.

lapping breaks. Strikes N.

40--55- W. Dips 70- SW.

except for vertical to steeply

NE dip near Lake Elsinore.

Length at least 28 km.

17 Glen Ivy South---------------Single strand. Strikes N.

35-855 W. Dips

45--50- SW. Length 7 km.

lt Wildoma ------------------ One to five subparallel strands

in zone locally 0.7 km wide.

Strikes N. 45--s5- W. Dips

steeply SW. Length at least

40 km.

Holocene (OS. PI

Holocene (PI

Holocene (OS, PI

NRO

RRO

NRO

Numermus closeiy associated

small earthquakes at

northern end. Possible

source of ML ti earthquake

in 1910.

Nunemus closely associated

smdll earthquakes.

Scattered small earthquakes

nearby.

C. E. Johnson (unpublished

data. 19821.

Langenkamp and Comb.

(11174).

Millman (11151

Rockwell and others (19815)

Weber (19771

C. E. Johnson (unpublished

data. 1912).

Langenkamp and Combs

(1974).

Millman (19t51

Weber (19771

C. E. Johnson (unpublished

data. 1982).

Kennedy (19771

Lamar and Swanson (19t811

Langlinkamp and Comba

(1974).

Weber (119771

19 Willard -------------------- Several discontinuous echelon

strands. Strikes N. 50--55°

W. Presumed to dip steeply

NE. Total length at least 35

km.

20 Wolf Valley-----------------Single strand. Strikes

N. 55--75- W. Presumed var.

tical dip. Length akm.

Late Quatea ry fOS. PI

Laet Quastrntry (OS. P. W)

NRO

SR

Scattered small earthquakes

nearby.

Numemus closely associated

small earthquakes.

C. E. Johnson (unpublished

data, 19821.

Hart and others 119791

Langenkamp and Combs

(19741.

Kennedy (1977)

Weber 119771

Hart and others (11979).

C. E. uohnson(unpublished

data, 1982).

Kennedy (119771

21 Muritta ---------------------- Severel overlapping strands.

Hot Springb. Strikes N. to- E to N. 70-

W. Dips 80-485 S. Length

at leastIZ km.

Late Quaternary (OS. P. W)

22 Norwalk--------------------- Presumed single strand.

* Strikes N. B5--8S- W.

Dips steeply NE.

Length at least 14km.

Possibly late Quaternary (P) RI?) Scattered small earthquakms

NE. of fault trace. Possible

.iun:,: for dlaittagoig 1929

earthquake (ML 4.7).

Lamar 119731

C. E. Johnson unpublished

data. 1982t.

Richter (1958)

Yerkes llY721

__________-------F our subparallel -. faults in zone

2.0 km wide. Strikes N.

10-45- W. Dips 70- SW. to

55- NE Lengths hmm I to

1.5 km

Late Quaternary (OS]; historical

119681surface rupture along

westernmost fault probably

related to withdrawal of oil

and gas.

RLL Morton and others (19733

Yarkes (19721

Single strand.

Strikes N. 0- W. to N. ao- E.Dips 0--0 N. Length at

leat a km.

Late Quaternary (OS. P) R 1

Numerous small earthquakes

nearby.

Bryant anid Fife (1982)

Fife and others (1910)

C. E. Johnson (unpublished

data, 1982).

Morton and others (19731

Schoellhamer and others

(1981).

N

23 Faults in----

West Coyote

HIII

Kennedy 119771

Z4
TABLE 3.1-1 Geologic and seimologic characteristics of late Quaternary faults in the Los Angeles region-Continued

Type of

Aga and evidence late

of lateac Quaterary

Map number and fault Geometric aspacts sorface faulting offset Seisricity Sourcs -ofinformation

Newport-tnglewood fault zoner

25 Inglewood---------------Single strand locally offset by

short north- and

NE&4rending faults. Strikes

N. 5--30- W. Dips 70' W.

Length at least 13 kis.

25 Potrero -- ----------- Single strand. Strikes, N. 25-

WV.Dips 77r W. at surface:

82 IW.at depth. Length

7 km.

27 AvalonCompton ------------ Single strand.

Strikes N. 20m-30- W.

Presumed verlicaL

Length at leant 4 krmL

28 Cherry-Hill -------------- Single strand.

Strikes N. 391-501 W.

Dips 80' K

Length at lan krm.

29 Reaervsir Hill- -----------Single strand.

Seal Beach. Strikes N. 59- Wi.

Dips near vertical.

length at east 12 kmn.

30 Newport-lnglewod--------Qne to three closely spaced

(North Branchj. strands. Strikes N. 40'-80

W. Dips steeply SW. Length

at least la km.

31 Newport-lnglewood-------Single strand. Striks N. 4S-

(South Brarschl W. Dips steaply SW. Length

at least la kmnand possibly

oins similarly oriented fault

offshre DanaPoint.

32 Faults offshore of-------------Two ochelon strands. Strikes

San Clemence. N. 45-55- W. Dip

unknown. Length of each

fault at Inat 25 kmn.

33 Pican Hilll------- ---------- Several strands.

Strikes N. 1-35' WV.

Dips 25- tS. at surface but

45- W. at depth.

Lace Qusternary JOS. Pt surface faulting since 1957

locally along north-trending

faulls in responseto

withdrawal ofl and gas.

Late Quaternary [P. W)

Late Qusternary [I. W];

hisntorical [1941.1944

faulting within 1.5 kissof sUrface along subsidiary southdipping reverse faults.

Late Quaternary (OS. P. W)

Late Quatenary (05. P. WI

Holocene (OS. W3.possible

historical surface faulting

(19331at Newport Mesa.

Late Quateamary [P)

late Quaternary [0O, P]

Late QuAternary [OS)along

subsidiary fault

N or NRO

N or NRO

SRI?]

R or RRO

NRO or SR

SR

SR

SRO

N or NRO

Numerous small earthquaka

nearby. GeCmetrically

compatibla fault-plane

sAuluirio. Posaibla source

of 1920 earthquake '[ML

j.9

Nuroerous sia) earthquaks

nearby.

Scattered smal arthquakes

nearby. Epicenters of 1941

,ML 4-9]and 1944 [ML 4.5]

lie SW. of fault Utca.

Numerous small rarthquakaa

lie east of trace. Fault

mielis aftershock zoe of

19(3 Long Beach authquaka [M 523 1141Torrance-Gardena earthquake

'ML SAjilocatnd SW. of

fault trace.

Numerous small earthquaks

near trace. Fault ovarlia

aftershock zone of 1933

Long Beach earthquake tM

1.23

Scattednd small sartlhquala

near trace. Fault is adjacent to aftershock zone of

1933 ong Beach earthquake [M ,523

Scattorud small earthquakea

near trace: Fault is adjacent to aftershock zone of

1933 Long BEch earthquakes(Al23.

Concentrations of small

eartlsqua locally along

tracal.

Scatternd small ea1thquake

wealof trace,

Barrows [29741

Buika and Tang 1397)

Castle and Yea (1975]

Poland end others [(99)

3-C. Tinsley (u[pubriqb

data 19833.

Baorowa l1974)

Buika and Tang [179]

Poland and others ([106

Bravinder (1942]

Buika and Tang a179]

Maner (19483

Poland and Othera (1959]

Hiileman and others j19;31

C. E fohnson [unpublisd

data. 19821.

K. K Lajoie (unpubisd

date, 1933.

Poland and Piper (19)58

Yerio and othenr (165]

Hilrnean and Others (1973]

C E lohnson uublsheda

data. 19823.

Poland and Piper [19)51

Californa Department of

Water Rescurca [19f88

19883.

Cuptill and Heath [19811

Hileman and othaes,[1973]

C. e [ohnson (puapubllhed

da 19823.

California Department of

Water Rsmurmes [1988)

Hilaman and otbars (1973

C. . Johnson (unpublished

data. 198623

Poland and Piper [2195

Clam and others [thIs

volunel.

C. E Johnson (unubl

data, 1982

Case [19883

Morton and cther (19731

3.K S&I1n lpsnone aewmunication. 1933.
TABLE 3.1-1 Geologic and seimologic characteristics of late Quaternary faults in the Los Angeles region-Contiaued

Type of

Age and evidence late

of latest Quaternary

Map number andfault Geometric aspects surface faulting offset Seismicity Sources of information

34 Cbarwck and------------------Two fault strands.

Ovedrand Avenue. Strike N. 35- W.

Preeumed vertical dip.

Length at laesdo km.

35 Palo. Verde. Hills-------------- Several echelon strands locally

in a zone as wide as 2 kn.

Strikes N. 20--0- W. Onshore segment generally not

exposed. Dip 70- SW. in

subsurface of Palos Verdes

Hills, although exposed subsidiary fault dips 75- NE.

Total length at least so km.

Late Quaternary OS); no surface expression.

Holocene (OS] in San Pedro

Bay. Late Quaternary (OS. PJ

onshore and probably

overlain by Holocene

alluvium. Inferred late

Quaternary (OS)in Santa

Monica Bay.

Nunermus small earlhquakes

nearby. Geometrically

compatible fault-plane

slutirions.

R or RRO Numerous small earthquakes

near and west of fault

trace. Ceometrically compatible fault-plane solution

in Santa Monica Bay.

Buikd and Teng 11979)

Poland and others (10990

Buika add Tang (19791

Clarke and others (this

volumel.

Hileman and others (19731

lunger and Wagner (19771

Nardin and Henyey [1978)

Poland and others (1959)

Wooding and others (1948)

Yerkes and others (19051

resumed single strand. Strikes

N. 80-85° E. Dip unknown.

Length approximately 13km.

Holocene (P3 RF?1 Scattered small earthquakes

near trace.

Nardin and Henyey (19780

Yerkes and others (10973

Strikes N. 20--50 W.

Dips 50--75- onshore.

Length approximately 18km.

38 Son Pedro Basin----------------Series of separate. left-stepping

fault zone. echelon strands in zone

locally as wide as 5 km.

Strikes N. 35'-50' W.

Presumed vertical dip.

Length of individual strands

4-12 km: length of entire

zone at l3ast 70 km.

30 Faults ofthe-------------------- Echelon strands in zone locally

4 km wide. Strikes N.

50- 0° W. Length of individual strands 5 to 40 km:

length of entire zone at least

120 km.

Holocene (OS] offshore

LadeQuaternary (OS)

Possibly late Quaternary (PI

NorNKO

SR or RRO

SR,

Scattered small earthquakes

near fault trace.

Nuinerous sntall earthquakes

near and east of fault

tradces.Geometnicully compatible fault-plane solutions.

Source of 1981Santa Barbuar Island earthquake

IML 5.21and aftershocks.

Clarke an.dothers (this

volume.l

Darrow and Fischer (10833

Hiluman and other (19733

lI ollrll 1illlehrs (19793

Wuodring and others (1948

H(ilenan and othera (19733

lunger and Wagner (19773

Nardin Idt8t1l

Yerkus anid Lee (1979a. bl

C E.ohnson (unpublished

data, 1921.

Corbett and Piper (19813

C. E. Johnson lunpublished

data. 1982k.

longer and Wagner (19773

Yerkea and Lee (1979s. bI

Faults of Mojave Desert region:

40 Llano------------ - Singlestrand. Strikes N. 8s5

W. Presumed dip to SW.

Length at least km.

Holocene (P3monoclinal

folding.

R Guptdil and others (19793

Ponti and Burke (19801

41 Mirage Valley---------------Several echelon strands, each

1-7 km long, locally in zone

3 km acrosa.Strike N.

40--5o- W. Presumed vertical dip. Total length of

zone approximately 30 km.

Late Qusternary; overlain by Ponti and Burke (19803

unfaulted Holocene alluvial

fan deposits.

42 Helendal ...------------------ Numerous echelon strands, I

to 4 km long, forming narrow linear zone as wide as 1

km. Strands strike N.

45--50° W. Presumed vertical dips. Total length of

zone at least 90km.

Holocene (PI SR Closely associaled ntail

Iarthquakes.

C. S. Fuis (unpublished data,

19831.

C. E. Johnson (unpublished

data. 19821.

Miller and Morton (19801

Morton and others (19t03

Santa CruzCatalina sea-floor

escarpment.

SRI?)
TABLE 3.1-1 Geologic and seimologic characteristics of late Quaternary faulls in the Los Angeles region-continued

Type of

Age and evidence late

or latstg Quatemnasy

Map number and fault Geometric aspecf surface faulting offset Sersricuty Sour of information

Fults of Mojave Desert region (Continuadl:

Jumemus closely overlapping

nehelon strands. 1-5 km

long. forning continuous

narrow zone. Strands strike

N. 2S-4a1 W. Prurnmed

vertical dips. Total length okf

zone at least 55 km.

Late Quaternary If). Possible

historical fault creep et

northern enrL

SR Closdy associated small

earthquake.

Church and others (1974)

G. S. Fuis (unpublished data.

193].

C. .L(ohnson (unpublished

datl 19621

Miller and Moton (19601

Morton and othaea (19101

Faultt within Transverse Ranges

44 Santa to seven strands in zone

as wide as k3ont. Strikes N.

Sar W. to N. &5-S Dips

45-6& S., geneually

steepens eastward. Total

length t3t km, late Qutetenary length approximately Bo

ion.

Possibly Holocene (OS] along

one strand near lake

Cachuma. Late Quaternary

[OS. Fl as far est as near

Wheelar Spring

SL Darrow and Sylvt [1963]

Dibbles I1t65]

Keaton (1971)

YarBa nmdLee 4197t. h]

1. L Ziony lunpumPbhe da

19611.

It E Troutman unpuwblad

data. 1964).

45 San lowe (A}--------------One to two strands. Strikes N.

-Bo, W. Dip unknownL

Length approximately 13 Ian.

Late Quaternary (CS]

46 Mission Ridge- ------------ Single strand. Strikes N. 98' &

Arroyo Parida. to N. B5= W. Dips steeply S.

near Santa Barbatr but dips

es-So N. further east.

Length approximately 40 km.

47 More Ranch-------------One lo Iwr strands.

Strikes N. bac W. to N. 30-

S. Dips 75-05! S. Length at

least 14 km.

43 Mesa-Rincon Creek------- Single strand. Strikes N. 60S

W. to east-west. Dips

55--35' S. near surface;

probably vertical at depth.

Length approximnately 37 km.

Late Quaternary COS.Pt apparently overlain by unfaulted Holocene alluvium.

Late Quaternary (CS, P]

Late Quaternary (OS. PI

N

Rt

Rt

Scatered mrnall earthquakes

near trace. Mission Ridge

fault possible source of

197. earthquake JML 5.11

Scattered small earthquakea

sear trace.

Scattered small earthquakes

near traen.

Dilblee 119661

(ackaon and Yeats 11602)

Yarkes and Lee (19796.S]

Rockwell 119531

Rockwell and others 41964)

Yeats and lson 41984]

Dibblee (19651

ECE. Laioia (unpublish

data. l9631.

Upson (1951]

Yerkes and Las j1976 b]

Dibblee (1966

Jackson and Yeats (1962)

Yeries and Lee (19796.bI

49 Laigia ---------------- One to two strands. Strikes, N.

50--75- W. Dips 45' SW.

Length at least 7 ken.

SG Shapard Mesa--------------Single strand.

Strikes N1.50-70- W.

Dips 70' S. Length Skn.

51 Carpinteria ------------- Single strand.

Strikes N. 75- W.

Dips 40- S,

Length 4 km.

Late Quaternary 1051

Late Quaternary JOS. Pl

Late Quatenary [CS)

Scattered small eartlquaks

near trace.

Dibblea (1966]

Olson 11962)

R Jackeon and Yeata [192)

ft

leckson and Yeats. 11621

K. R.Lajose (unpublished

datar 1953)

A. MA.Sarna-Wojoid (urn[

published data. l924

43

NIT) Dibles i96l1

Olson (1962]
TABLE 3.1-1 Geologic and seimologic characteristics of late Quaternary faults in the Los Angeles region-Continued

Type of

Age and evidence late

of latest Quaternary

Map number and fault Geometric aspects surface faulting offset Seismicity Sour:es uf information

Faults within Transverse Ranges-Continued:

52 Red Mountain---------------Several strands in zone

1 km wide. Strikes N. 85- W.

to N. eo- E. Dips 55--85 N.

near surface; 70--75- N. at

depth; 85- N. at western

end. Lengith approximately

38 km.

Late Quaternary (OS, Pt

southern branch overlain by

unfaulted Holocene marine

terrace deposits (2.000-e.00

yr B.PJ.

RLO Nurmnruus clusely associated

Snalil uarth4uakus.

Ceoumetnricallyconspatible

fault-plane solutions.

Jackson and Yeats (19821

K. R. Iaouiu lunpublished

lati. 19i,3l.

A. M. Sarna-Woicicki (unpublished data. 1982,.

Yeats and others (1961,in

prmssl.

Yarkes and Lee (1979s. b)

53 Fault Y--------------------Probably several strands.

Strikes east-west to N. 80- E

Dip unknown. Length

approximately 33 km.

oaoenS terd smelt earthquakes

near trace.

Crippen and others (19821

Yerkes and Lee 11979.. bl

Yarkes and others (19611

54

Strikes N. 80- W.

Dips 68- S.

Length at least 4 km.

Holocene (OS) A. M. Surna.Woicickd and

others (in prasa,

Holocene (OS, PI RWL

Strikbs N. 70- W. to eastwest. Dips steeply north.

Length at least 50 km.

Closely associated small

earthquakes near eastern

end. Geometrically compatible fault-plane solutions. Possible source of

t941Santa Barbara earthquakes (M tiO). Alternate

pussible source ;or 1978

Santa Barbara earthquake

(ML 5.11.

Curbett end lohnson (19621

Qruune and othera (19781)

Lee aindothers (1978e1979)

A. M. Sarna-Woicicki (unpublished data. 1976l.

Yurkes and Lee (1979I bW

56 Santa Anat------------------Two strands at western end.

Strikes east-west. Dip inferted steeply south. Length

13km.

Late Quaterary (P. W) R4?) Keller end others (1980)

Rockwell and others (19841

Strikes N. 600 E. Dips

30-8-0 SE. May become

bedding-plane faults at

depth. Length from I to 3

km.

Holocene (OS, P) R Kellur and others (19621

Rockwell 119831

Rockwell and others (19641

Yeats and others 11981)

58 Lion Canyon----------------Single strand.

Strikes N. 0- E.

Dips 30-50- S.

Length approximately 15 km.

5o San Cayetaino---------------Two strands about o.5 km

apart west from Sespe Creek,

single strand to east. Strikes

N. 60 W. to N. 70- E Dips

5--35- N. near surface

55s-70- N. at depth. Length

*pproxinately 40 km.

Late Quaternary (OS. P)

Holocene (OS. P)

Schlueter (1975)

Keller and others (1960)

R Scattered nearby small earthquakes. Geometrically

compatible fault-plane

solution.

Cumen (1977)

Keller and others (1982)

Ruckwell (1982. 1983)

Schlueter 119756

Yerkes and Lee (1979a. b)

80FaultsofOrcutt--------------Eight separate strands.

and Timber Strikea N. 80sE.

Cinyooa. Dip 55--70- N. near surface.

May become shallow

beddingplane faults at

depth. Lengths from 2 to 6

km.

Late Qusternary (OS. P) Keller and others (1980)

Rockwell (11983

Yeats and others (19811-

55 Pitas

57 Faults nearOak View.

Holocene (PI

R
TABLE 3.1-1 Geologic and seimologic characteristics of late Quaternary faults in the Los Angeles region-Continued

Type of

Age and ewidece tale

of latert Quaternary

Map number and fault Gsoetric upects aurfece faulting Offset Seisnicity Sources of information

Faults within Transveree Rangae-Coninrued

51 Hcs --Se a dosedySpaced strands.

Strikes N. 0- . to N. M7

W. Dips S0-70' S. length

approximately 12 km.

Late Quaternary LGS.P]

62 CQaw ster----------- One ta two strande. Strike N.

sw W. to east-west Generally dips 7 '-W' N. but locally 2s-40- N. LateQuaternary length approxlrnately 

km.

63 San Gabriel-----------Several echelon atends in zone

(C-atel portio 0-.5km wide. StrikesrN

45'5-8 W. Dips 50-Wr N.

Late Quaternary length at

lean 32 kr

64 Oak Rid e------------- One to tiree strands in zone -

much as 0.5 kn wide.

Strikes N. e0c W. lo N. 50'

E Generally dips 65e-a-WS.

but south of Fillmore dips

5-30- S. near surface.

Length approaimately 100,

Late Quaternary (OS] near San

Frarcisquito Canyon but

overlarn by unfaulted hIte

Qusternery river terrace

deposits eLsewher

Holocene LOS.W)near CeetaIc.

Late Qustera (OSCF)be.

tween Newball and Big

Tujurga Canyon.

Late Quaternary [W, P1

possibly Hulocene south of

Fillaore (PIand offshore.

N or NRO

R Numerous closely associated

small earthquakes near

western end. Georntrically compatible fault-plane

solution south of Santa

Paula. Western and postible source of 1925 Santa

Barbara earthquake (M

0.8)

Los Angels County

Engrr.ua l

data, 195).

S5anlay (1988

Cottan and others 1o3w)

Nellgan 4l95

Stit 41983)

Weler [(97& 19;2; ufr

publisw dat 1984)

Ricketts and Whaley [175]

Riser (198l31

Weber and Kling (19751'

Yeats end others (19[L S11M

Yerk and Lea 19%b)

68 Springvlle--------------Two strands in zone about 0.

km wide. Strikes N. 855-75-

E.Dip 55s--E0 N. Ibengh

about 9 km.

e6 Cnaaio ------------ Single strand.

Strikes east-wes.

Preumed vertical dip.

Length at lea 6 rM.

Late Quaternary W, W]

Late Quaternary (P.WI

87 Sim----------------- Single strand that bifurcates at

western end. Strikes N.

70'-W' E. D[lips6-75i N.

LengtL approsinatey 31 km.

e8 Sat Suna ----------- Several strands in zone As

much as I km wide. Strikes

N. 75- W.to N. s f-Dips

O -30 N. near surface;

55-E0C N. at depth. Length

28 kh

U San Fenando-------------Five majo echelon strands.

Strikes N. 75' E. to N. 70-

W. Dips or-so- N. near

surEfsc, 35' N. at depth.

Total length at least 15 km.

Lale Quaternary LOS,Pi

overlain by unfaulted

Holocene alluvium (about

4M= yr 8.P.-

Late Quaternary OSk ovedrlain

by unfaulted Holocene

stream terrace deposits lapproximately l1O yr B.P.,

Locally at nrtheastern end.

historical surfcac fauliting acconmparied l9l San Fernando eeartq

Surface iauttingaccompanied

1971 San Fernando earthquake.

RLO

Closely associated small

eerthuquska. including ML

31. event in 19Mt

Scerternd jasciated amall

earthquakes. including ML

4.8 event near GIlibrand

Canyon in 1978.

Geomtrically compatible'

Fault-plane soluticns.

RLO Source of 1971 San Fmerndo earthquake (M Ui]and

aftershocks. Geonetrically

compatible fault-plane

solutions.

Iake 119791

C.E. (ohnon (unpublls

date. 1982)

Hanson (1981]

Weber and Kilalin[(1971

Leighton and others (1977]

Lung and Weick 41978)

Strail and others 11982]

Weber (1975]

Yeats and other 11977)

Yerkes and Lee (197k. b]

Allen aud others (1975)

Barrows 119751

Bonilla (1973]

Kahle (1975]

Sharp (191

US. Gologcial Su41 y Sta

41971). W b (19751

R. Cternen (1977t

Stit 19B83]

Wter 19178,19821

IJaw.419791

Gardner tl921

Iskeas 1197]
TABLE 3.1-1 Geologic and seimologic characteristics of late Quaternary faults in the Los Angeles region-Continued

Type of

Age and evidence late

of latest Quaternary

Map number and fault Geometric aspects surface faulting offset Seismicity Sources of information

Faults within Transverse Ranges-Continued:

7t0 Mission Hills----------------Presumed single strand.

Strikes N. 80- E. to esst-west.

Dips aC' N. near surface,

435 N. at depth. Length at

lest 10 km.

Late Quaternary or Holocene

(OS, P. W1.

71 Nortidge----------------- Several echelon strands in zone

0.7 km wide. Strikes N.

70-t3-8 W. Dips 35' N. near

surface, 80' N. at depth.

Length approximately t5 km.

Late Quaternary or Holocene

(P. W].

Several aftershocks of 1971

San Ferriando earthquake

are closely associated with

fault.

Barnhart and SIosson (1973)

Shields 119781

Weber j19801

72 Verdugo ------------------- Presumed multiple strands in

zone 0.5-1.0 km wide.

Strikes N. 501-70- W. Inferred to dip 45-E0 NE.

Length at lamst20 km.

Scattered small earthquakes

near trace.

C. E.Johnson (unpubllahed

data, 19821.

Weber (1980)

73 Eagle Rock-----------------Single strand. Strikes N. 80-

W. to eart-west. Dips

15--30' N. at western end.

Length at leat 5 km.

74 San Raa el------------------Echelon strands.

Strikes N. t0l-70- W.

Presumed nearvertical dip.

Total length approximately

6km.

Possibly late Quaternary (OS.

PI.

Possibly late Quaternary (PI

Strikes N. 80- E.

Presumed vertical dip.

Length approximately 2 km.

Possibly Holocene IPI

Faults along southern margin of

Transverse Ranges:

76 Santa Roea Island------------Single strand. Regionally arcuate, striking N. 50- W.at

western end and N. 60- E.at

eastern end. Dip unknown.

Length, at least 72 km.

77 Santa Cruz Island------------One to three echelon strands in

zone as wide as 0.5 km.

Strikes N. 70° 0- W.Dips

70'-75' N. Length at least

8 akm.

78 Anacapa (Duimel

Late Quaternary (OS, PI

Late Quaternary (OS. P)

resumed single strand in Probably late Quaternary (P)

west: multiple strands in

east. Strikes N. 80' W. to N.

60' E. Inferred to dip

moderately north. Length at

least 45 km.

RLO

RLO

R

Probable source of April 1.

1945,carlhquake (ML 5.4).

Generally tacks small earhquakes. Possible source of

M, 5.0 earthquake near

Anacapa tsland in t973.

Source of t973 Point Mugu

earthquake IM 5.31and

aftershocks. Geumetncally

compatible fault-plane

solution.

Hilenian and others (19731

Junger 1197t1it979S

Kew (1927(

lunger 1197t.19791

Patterson 119791

Yerkes and Lee 11979a.bl

lunger and Wagner 119771

Leo and others (19791

Yarkes and Loea1979a, bl

Late Quaternary OS)

Nunmrous small earthquakes

nearby.

K. R. tLajoiLlunpublished

data. 19331.

Yerkes and Wentworth

119651.

C. E. Johnson (unpublished

data. 1982l.

Kowalewsky (19781

Saul (19751

Shields (19781

In North

Hollywood.

Weber (1980)

Weber 119801

Weber 159901

zone as wide as 0.5 km.

Strikes east-west and dips

45-30' N. Length at least

27 km.

Rl?l

?

Holocene (OS, P. W)
TABLE 3.1-1 Geologic and seimologic characteristics of late Quaternary faults in the Los Angeles region-Continued

Type of

Age sandevidence late

of latest Quaternary

Map nurbner and fault Geometric aspects surface faulting offset Sesity Soumes cf informadcn

Faults along southern margin of Transverse Ranges-Costinued:

W Sant Monica----------One or more strands.

Geometry poorly known.

Strikes N. 50--W- E.

Presumed to dip 45'-65-

NW. at depth; some nearsurface traces am vertical.

Length at Ias 40 kit

S1 Hollywood----------- Presumed single strandL

Geometry poorly known.

Strikes N. a M'W. to N. 60-

E. inferred to dip about er

N. Length approximately 17

Ian.

82 Raymond - ------- - One to three strands locally in

zone 0.4 kin wide. Strikes N.

Ss- W. to N. 70- E. Dips

5s--55' N. Length 22 km.

83 Slams Madre ------------ One to five anastomosing

strands in zone as wide as I

km Four diutinct saliants.

Strikes N. 597 U'. to eastwest. Dips i15-5,- NE. and

north. Tota length approximately as kmn.

Late Quaternary (OS, P. WI

Possibly Holocane l;F

Holocene (OS. P. Wn Overlain

by unfeulted sail (1.60 yr

O.P?.]

Holocene (OS. P] between Big

Tujuoga and Dunsmore

Canyon&s ELsewherm Wate

Quaternary (OS. P. n] zOsaralinby unaulled Holocene

alluvium il several place

RLID

R or RLD

R or RID

R

Small esrthquaka closely

associate with eautern

end. Geometrically cornpaltbleio4fsut-prlam solution.

Some small aarttquis

associated with aetem

end.

Scattered small earthquake

lie north of fault trse.

Possible source of 1835

Los Angela eairthuake

[Modified Mercalli tentty V1l. Geometrically

compatible fault-plan

solution.

Few end scattered small

earthquakes.

Buika and Teong 11929)

Crook and others 19t33

Hill 119791

Hill and othes (99

McGill (1il0. 1882]

Real [in prese

Crook and othae 1193]

Hill and others 1979

Wber [t1988

Bryirt (1978(i

Crook and oitan in ePr-)

Red Urnpreal

Weber (10)

yTis (this Volumet

Crook and othersfin prsJ 

pFcmo rn pree

84 0uarte---------- --- ore to two subparslld strands

locally in zone 1.5 km wide.

Strikes N.s8G W. to N. 70'

E. Poesumed to dip steeply

NE. Length approximately

14 km.

85 Clamshall - ------------- Several subparallel strands in

Sawpit Zone. zone as wide as I kn.

Strikes N. 5D -E DIpe

35-7C NW. Length appoximnately 18 irn.

Late Quaternary ffb possbly

Holocene (P. W] along northeMOstrand nesr Azaa

Late Quaternary 10S]

R

R

Crook and otes (LOpr-a

Morton [1973]

Crook and others (inpit)

86 Cucamongs----------- wo to tonts suaparera

strands in zone as wide as 1

krts.Strikes N. 70 E. to eastwest. Dips moderately to

steeply north. length at (aut

25 km,

8 Indian Hill- ------ Presumedsingle strand.

Strikes east-west

Dip presumed steeply north.

Length approximately 9 km.

Holocene (OS. P] along

southern strands. Late

Quaternary (OS] along northern strand.

Late Quaternary [P. MV

R Numerous smsall earthquakes. Geometrically

compatible fsult-plane

soluttns.

Scattered small evithquak

nearby.

Matti and others (1983 In

press]

Mcrton and Matti (in pres

Morton and others ,[19

FPacmano (in psea1i

California Department of

Water Resources, (1970

Cramer mndHarringon

19.L in pres.

C. Johnsoo 1 tunpsbad d"t 1882.
TABLE 3.1-1 Geologic and seimologic characteristics of late Quaternary faults in the Los Angeles region-Continued

Type of

Age and evidence late

of latest Quaternary

Map number and fault Geometric aspects surface faulting offset Seismicity Sources of information

Faults along southern margin of Transverse Range*-Conttnued

88 San Jose ()----------------Sinngle strand.

Strike N. 45-eo E.

Dip presumed steeply north.

Length approximately 22 km.

89 Red Hil--------------------Presumed single strand.

Strikes N. 20- W. to N. 70-

. Dip inferred steeply north.

Length approximately 13 km.

Late Quaternary (W); overlain

by unfaulted Holocene

alluvium.

Late Quaternary (P. W) except

Holocene (P) at eastern end.

SL4?) Scattered small earthquakes

nearby. Geometrically

compatible fault-plane

solutions.

SL47) Scattered small earthquakes

nearby. Geometrically

compatible fault-plans

solutions.

California Department of

Water Resources (1970).

Cramer and Harrington

1984. in press).

C. E lohnson (unpublished

data, 1982)

California Department of

Water Resources (1970).

Cramer and Harrington

t1984.in press).

Hadley and Combs (19741

C. E Johnson (unpublIshed

data, 1982).

Morton (19781

90 'Barrier J:------------

91 Inferred fault-----------

near Fontans.

Faults along margins of San

Bernardino Mountains:

rA- v _ _ _ _ _ _ _ _

93 North Frontal---

Fault Zone of

San ernarudino

Mountains.

Strikes N. 45- F

Dip unknown.

Length at least 5 km.

Inferred from seismicity to

strike N. 45 E. Dip

unknown. Length at least 8

km

Single atrand. Strikes N. t0

W. to N. 75- E. Dip near vertical. Lengtb at least 23 km.

Jumerous discontinuous arcuate strands averaging 2-4

km long, locally in a zone as

wide as 8 km. Strikes N. 10°

E to N. 50- W. Dips from

10--70 SE. or SW. One

5-mrtlong NW.-striking setment Lsvertical. Total length

of zone at least 50 km.

Late Quaternary 1W);no surface expression.

Possibly late Quaternary: no

surface expression.

Probably Holocene (P)

Late Quaternary (OS. P):

overlain by unfaulted active

Holocane alluvial fans.

S147l

SL

R (except

vertical

[NW.-striking

strand may

be SR)

Numerous closely associated

small earthquakes.

Numerous closely aligned

small earthquakes. Composite fault-plane solutions

sugtgest taft-lateral strikeslip faulting.

Numerous small earthquakes

near eastern end of trace.

Numerous closely associated

small earthquakes near

eastern part of zone

California Department of

Water Resources (1970).

Cramer and Harrtigton

(1984, in preas)

Hadley and Combs (19741

C. E. Johnson (unpublished

data. 1982).

Morton 11978)

Cramer and Hatrrington

(1984. in press)

Hadley and Combs 11974)

Morton 129761

C. E. Johnson (unpublished

deta, 19821.

Meisling and Weldon (1982a.

hl.

Maisling (19841

C. E.Johnson (unpublished

data. 19821.

Meisling (19841

Miller (in press)

94 Faults of the----------------Several arcuste echelon

CralRon Hills strands, each 2-8 km long.

(Crealon. Chicken Strikes N. 50o--0 E

Hlil, and Casa

Blac faults).

95 Banning ------------------- Two to three strands in zone

locally 4 km wide. Northern

strand strikes N. 70' W. to

N. 85' W. and dips 350-700

N. Southern strands are

complax, arcuate segments

3-10 km long that strike N.

65- W. to N. Slt E. and

presumably dip moderately

north. Total length of zone at

least 45 km.

Late Quaternary DOS.P)

Holocene (OS, P. W)

Green (19831

1.C. Mani (unpublished

data. 1983).

Morton (1978)

R [except

NW.-striking

segments

probably SR).

Numerous closely aseoci tad

small earthquakes.

Geometrically compatibla(?)fault-plane solutions

Allen (19571

Green (19831

Matti and Morton (1982)

Yerkes (this volumal

C. F. Johnson (unpublIshed

data. 1982).

-
Chart of Quaternary Time Period

Holocene Epoch

Late

Pelstocene

C3 a <; -~128 

Pleistocene

time

a. uO Li -750~ 7 LiOa

> V tw %s, Hotocene Epoch

Z u <w _ _ Fleene j\

L., o ~~~~~~~~~Epoch

< C3 aL ~~~~~~~~~Pliocene 0G i early / L Epoch

Pieistocen C L

tine I£1 <~poch 

_ _ / ta < 4 0 \< 

Naocene

Epoch

._ l I~Epoch /) 2 u Q~~~~~ CENOZCIC ERA

38 T -63

> /ESOZOIC M~~ ERA

L ocene 240 SZ

Epoch 0/ E/

__________ ~PALEDZUI4C ERA

Pateocenew

Epoch 

___ ______ h5~~~70

_Ut '~~~~~~~PRECAMBRIAN, 2

-j

TIME _jx

4550
117 Si S 26 117 32

I 'C* I 2I

-n: S F 'ta~~~~~~~~~~~~~~~~~~~~~a

*z] -l<eqX ['Il'\

i - -'-- - - - = =

itt2

': ? V & Wa. I C~~~~~i _

SCALE~~~~

oa Al

RA_D1 I0- RRfD

-P r- P ~ o

________ G __- - AG P

/ W1Maui , -- 0 d2

iiiiia CONT§U P1am2 DN Di n 1 1

Ewxrnw CONTOUR WrM 20 -1T

EXPLANATIO

,'\M xOAIA'

'K >Z\ 't' WA

) *~~~~PUMA

1 '1o)n \~~ w(

-------V---- V - FLME-PENSTOC

o - --- o- uT~ig-b mto cr''mx -------- G -- 1-G" L GS IALO JNCn

a - - - - -F Z P I ABI

I
4~ L1731.4' I7._ - rZ.,I ft.

.I

I .

~~~~~~~~I

,.I_ -- - ------

"N

2I-

. I AV-

; . fi

I J

f I

pi m

tt*

. - (,/I

,; f I r

Ut

; . Ff - 2 ,-; I_1

>11 v" KJ't c- / IA\ 

T4i

T31

4,4 I Gil- I

('SA N RE RIG TN"A

AL~~~~~~~~~~~~~~~~~~~AJI

ISOSm

~~~~~~ /~~~~~~~

ilkN~ N r

5k '2j

..Ln~~~~~~~~~~~.

'N

1.4' 1173.'

NW I 

$Mk |n(Arm '|MloNwm .

1 1_

S '_ -i _ _ _ _ _ _ _ _ _ _

t -- -S. - -

a-z 1

4 --

_~ _d- _d asI

-". _ _%"A* h." *_

__, -

b WMON

I

117-li.,.

2 mmLES

Faula

Uld in eil heaed: dmnhedwhr qpprmxiardy kend ihfemd. IduS uw emiehsmim ofrceh.ame uermeia: daierd -bent troweled bT _M itr

Figure 3.1-2 Active Fault

In The Study

Locations

Area

11

i i 3

I-)

T3

Si

k

Tl

T1

e

lii1.

i

i

i

J

1J'21 .91 

_ 1 117'31.4' 117'30' 

. ,~-

f 0

TT3Kl -c
25

SCALE

r 1 2 KILOMETERS

EXPLANATION

HIGH WATER TABLE

[E

;EFQiT

71'

EE]

El

Pcr

4J

ALLUVIUM

WASH DEPOSITS

OLDER WASH DEPOSITS

LANDSLIDE DEPOSITS

YOUNGER FAR DEPDOSTS

OLDER FAN DEPOSITS

OLDER ALLUVIUM

WELL DISSECTED ALLUVIAL FANS

HAROLD FORMATION AND SHOEMAKER GRAVEL

CROWDER FORMTIOH

PUNCHBOWL (?) FORMATION OF CAJON VALLEY

Figure 3.1-3 Cajon Pass Region Geologic Units With High Water Table Regions Identified

gr1

r~,7

FT)7s

ER

Jgd~

gb

--- ? GEOLOGIC CONTACT OBSERVED OR APPROXIMATELY LOCATED; QUERIED WHERE 'GRADATIONAL OR INFERRED.

VAQUEROS (71 FORMATION

TERTIARY GRANITIC ROCKS

SAN FRANCISQUITO (7) FORMATION

PELONA SCHIST

CRETACEOUS GRANITIC ROCKS

CRETACEOUS OUARTZ D;ORITE

CRETACEOUS OR JURASSIC QUARTZ MONZONITE; QUARTZ MONZOITE OF PLEASANT VIEW RIDGE

JURASSIC OR CRETACEOUS GRANODIDRITE

GABBRO OF PLEASANT VIEW RIDGE

METASEDIMENTARY ROCKS OF UNCERTAIN AGE Is-LIMESTONE AND MARBLE

SHEARED AND DEFORMED METAMORPHIC ROCKS (AGE UNCERTAIN) I' GNEISS

m4 HIGH-GRADE METAMORPHIC ROCKS

i5

L? 3i 117 22

d -

a 117 22

,

110 II

-d0

m
;b 1 , A

A .-

Lowim a Lrm 

0 DWYED WEREEDISEMM)D

Figure 3 .1-4 Observed Landslildes Wi"thin the Study Area

'I

I

117r2.91 lt?- t .4 ' 11V 30 I RMw

k

I , I,

.,U '.

?/ I ,t)\ 44

Isc,-/ (- f�') &/' C_ ' 

I 

I _N

11 ,-, A f)

- I I' ')

/-ft, X,

' '\ /t

T44 o \[,''' -- /XX.;6X1

T31

T311

;m

H2

-i_

l (rll>]f -, i S -- - ¢ S s-/ -- 8 - -~~~~~~~~~~~i

<~~~~4 ! - ;i'- Lb

T31E

in

na

ai _L9- gmIKSM 117-213,t 117'31.4'

I

111-3EI 

19

EXPLAT10
117-31-4- m1m7,30 1S71S

- rN MM - , ,( . i-

- -~~~~~~~~- -f I _ 

/ -- ,- _

T411 ~ ~ ~ ~ ~ :o - U - Ta/ , > 1. 

T3N1 , , 'T31 ;

Tm - , -- ---- 73-

'~~~~ -. : 

* J '-

_ ~ ~ ~ ~ ~ ~ ~ ,/ - )-- '3 ~ .

l O E 0t # 1 ~~~~,' -- -' .

~~.de'sli -~- r *°o11 ,, 

, , ; : C_. l6

J~~~~~~~~~~~JI-

- - - ' - ~ --' ' '" - P t 2S 3/ 400

I . -0~~~~~

Qe ~~~~ X 0 , T Q~ -(} w

T~~ll - -~0 - gr~ - 7/0 IT_

7t_ ~r_~ -'? -< - 0,.iw -0---xVo1_ 

-. si~~~r

- -; ¢E - -1ZW~* 2 ,, 5/I,,,,< 

- - ' ---. . 0 ~ ~ 7 9

t- 7 xD. S 12./-49--'*--'r 11/60J ; X-

-7 K -<- DtJRIN / ~~~~~~~~~~~~~~13 03/C

L , >SFE RECW*-&MSS°AN2^t t a -

K E~~~~~~ASED ONOISERVATIUNCE-x>K--6 VN

7477 . <, . -~; ..- S _ 't' 767 'j14ll2W

, -- | l -N a & . - * C sI~e 79/142e 216 -

T2X~ ~~ ~~~~~9A . i" --- f4f2-42 \/ SbT4

- - -------------- S $

:$-~~~~~~~~ t$'Rfli 'I S

/~~~~~~ 1 2 IILS

O DEPTH111 ! LTERI C2LNU05' = = -

0 E H 65TER 6RllD oEEPE5'3135'

IflW' ~ REEEIC ~ ~ 110 ~ ~ .-5/1 >DPH106W01T 36EL ITU

I3 l 1N 

1/77' - "O~~~~~~J' vis

0~~~~~~~~~~~~~~~~~~~~~~~~7/0 - -~ AC 46/55

O

TIN~ ~ Fi r 3c n 111oai i hlo W tr T be Cod i n

.7- - '37,

- 1/V -

N~~~~~~

- 52/100-126'' - -1- 0'7/M-72LOC

54/172' ~ 0 ~ ~ ~ 7/1a,7K C -- 0 0 -U~~~~~~~~~~~~~~~~~~~~~~~~~4/2 

- 57/107' 3&x22 7100EDO -,782

11P31.4' lilnac'~~~~~~~~~~~~~~~~~~~413"*O

45183' 1830-10' 0-811725

EXPLANATION~~~~~~~~~~~~~~~~~~~~~~~~~~~~~0 I

TIN -2W~~~~~~~~~~~~~~~~~~012315

* ro urns cmii an ass mu wv

1/10-ES' ~FEENE uNC. (tABE 3.1-2)RUE CE DE~h 4T17Si 0TE

DEPTHETOEGMA TER LAESST 5

Figure 3.1-7 Location of Shallow Water Table conditions

23

I

i

I
0 

30 35 117 23

Figure 3.2-1 Map of the 'Communication Lifelines

SCALE

I 2 MILES

EXPLANATION

- I-15 INTERSTATE

a , . PAVED HIGHWAY

.-- ...F FIBER OPTIC CABLE

31

117 31 30 

11 117 P2

-In

0

0

N

a

gm

.0i -4

I- 4-

aa t

117 at

0

o 1 ; KILOMETERS
30, .2~~~~~~~~~~~~5

Figure 3.3.1 Map of the Electric Power Lifelines

SCALE

1 0MIIZ

~~~ L~-16

2

- ------ p -- ---- -

NTERISTATE

PAVED IUGIUWAY

POWER UKNES

BURIED AQUEDUCT

40

117 a,3

"r:

e

C

e

a ,0 1

IMT Sl

-0-

11? a2

0

U I =2 nMLDMERS T

EXPLANATION

- !G;;

Zz
I ladm'I1an L 21 -

117 22 30'

Figure 3.4-1

SCALE

I

IMap of the Fuel Pipeline Lifelines

2 MILES

a I ]CILOUSTERS

EXPLANATION

-. I-lB ,_

2

-...G...------- G...--

3 0 0

INTERSTATE

PAVED HEIGHWAY

PETROLEUM PRODUCT PIPELINES

NATURAL GAS PIPELINES

VALVES

47

.0

a .1 14

a 0 

117 St

0
a N3

'N $ 

4~~~ ~ 6

bCqm Ulm

RA.DI

TOWER

4~~~~~~~~~~~~~~~~~~~~~~~~~~~4

1I7 31 30 25

Figure 3.5-1 Map of the Transportation Lifelines

SCALE

O 2 HILES

0 I _ZaXILOURTEflS

EXPLANATION

1-1 _ I ERSTATE

2 PAVED IUGIWAY

-e 1--4--I--I ---~-* RA|IROAD

57

a 

117 22

c