text:
Elyse Golob, Ph.D., Executive Director, National Center for Border Security and Immigration,
University of Arizona
Yi-Chang Chiu, Ph.D., Department of Civil Engineering and Engineering Mechanics, Advanced
Traffic and Logistics Algorithms and Systems (ATLAS) Research Center, University of Arizona
Pitu B. Mirchandani, Ph.D., Department of System and Industrial Engineering and Director,
Advanced Traffic and Logistics Algorithms and Systems (ATLAS) Research Center, University
of Arizona
Gertie Agraz, Department of Industrial and Systems Engineering, Instituto Tecnológico de
Estudios Superiores de Monterrey (ITESM) Sonora Norte campus
Yunemi Jang, Department of Civil Engineering and Engineering Mechanics, University of
October 2008
Bottleneck Study – Mariposa Port of Entry Page 3 of 212
The Arizona-Sonora border has become increasingly important to both states' economy
due to increased trade between the regions following the 1994 passage of the North American
Free Trade Agreement (NAFTA) and the establishment of maquiladora industries south of the
border. Since the events of September 11, 2001 increased demands for border security have
presented further challenges to the efficient flow of cross-border trade. Most of the exports and
imports crossing the border are shipped by land transportation via truck or rail. These goods and
the industries they support are crucial to the economic development of the border region.
The purpose of this study was to identify bottleneck areas to and from the Mariposa Port
of Entry (POE) at Nogales that impact the efficient cross-border movement of goods and
recommend low-cost, high-impact solutions. Nogales is the primary port accounting for more
than three-quarters (77 percent) of all commercial traffic entering Arizona from Mexico and is
one of the country's largest ports of entry for fruits and vegetables. For this project, a bottleneck
is defined as "a condition that restricts the free movement of traffic, creating a point of
congestion where demand exceeds capacity for a given length of time." This study employs
traffic data collection and analysis to identify the location and nature of bottlenecks that restrict
the free flow of people and goods into, and away from, the Mariposa POE. The focus areas
include the roads immediately to the north and south of the Mariposa POE, respectively SR 189
(Mariposa Rd.) and the Corredor Fiscal (Fiscal Corridor), as shown below. The study also
proposes improvements to alleviate congestion at the identified bottlenecks and provides
estimates of associated costs.
Bottleneck Study – Mariposa Port of Entry Page 4 of 212
This is the second in a planned series of cross-border bottleneck studies funded by the
U.S.-Mexico Joint Work Committee (JWC) for Binational Planning and Programming. The first
study, focusing on the San Diego-Tijuana Port of Entry Gateway (Otay Mesa/Mesa de Otay and
San Ysidro/Puerta Mexico), was conducted by the California Department of Transportation and
completed in 2004. That study developed a methodology that could be utilized at other
international land ports of entry.
Findings and Short-Term Recommendations
Major bottlenecks were observed at several intersections/interchanges along the SR 189
corridor between the POE and the N. Grand Avenue/W. Mariposa Rd. intersection.
Bottleneck #1 W. Mariposa Rd./I-19 northbound (NB) On-Ramp Intersection
(a) re-time signals
(b) add an additional lane to the existing left-turn lane
(c) widen on-ramp and extend merge point further downstream
Bottleneck Study – Mariposa Port of Entry Page 5 of 212
Comments: Most delays occur at the left-turn lane. This spillback then affects the
I-19 southbound (SB) ramp traffic as well and the upstream Frank Reed intersection.
Bottleneck #2 W. Mariposa Rd./N. Grand Ave. Intersection
(a) coordinate the signal timing between the Baffert Drive/W. Mariposa Rd. and
N. Grand Ave./W. Mariposa Rd. intersections
(b) extend the right-turn lane on N. Grand Ave. SB at the N. Grand Ave./W. Mariposa
Rd. intersection.
Comment: Afternoon truck traffic returning to Sonora from Arizona tends to create
large right-turn volume at the intersection. At times, this causes spillbacks that impede
N. Grand Avenue SB traffic.
Bottleneck #3 Frank Reed Rd./N. Mariposa Rd.
(a) adjust signal timing at Frank Reed Rd. to permit more green time for N. Mariposa
Rd. approaches during periods of decreased traffic from Frank Reed Rd. and N. Industrial
Park Dr.
(b) move the flashing light further upstream away from the intersection for traffic
coming from the POE. This would provide appropriate stopping sight distance when the
signal is about to turn red.
Move upstream flash warning sign (Bottleneck #3); add left-turn lane & widen on-ramp
(Bottleneck #1); signal re-timing & coordination (Bottlenecks #1, 2, 3 plus other intersections
along SR-189 and near I-19) increase capacity of right-turn bay (Bottleneck #2)
Signal Retiming
& Coordination
Add left-turn lane
& widen on-ramp
Move upstream
flash warning sign
Increase capacity
of right-turn bay
Bottleneck Study – Mariposa Port of Entry Page 6 of 212
Cost Estimate
The total construction, engineering and project management costs of implementing all the
short-term, high impact recommendations for bottlenecks north of the Mariposa Port of Entry
are estimated at approximately 1.5 million dollars.
Long-Term Recommendations
With anticipated increases in throughput at the Mariposa POE, two more extensive
projects may be considered:
(a) direct connector from I-19 to the Mariposa POE separate from W. Mariposa Rd.
(b) frontage road east of I-19 between W. Mariposa Rd. and N. Apache Rd.
Comment: These two long-term projects will create a significant pattern shift in the
traffic flow, thereby alleviating congestion at the existing bottlenecks.
Findings and Short-Term Recommendations
Bottleneck #4 Fiscal Corridor
Place proper signage before the point where the road separates into private and
commercial lanes. This would allow vehicles traveling at free flow speed (i.e., the speed
when congestion is not present), to have sufficient advance warning to enable them to choose
the correct lane.
Bottleneck #5 POE Entrance - Truckless Drivers
Truckless drivers (cruzadores), who are Mexicans with border-crossing
documentation, often wait in front of the Mariposa POE for northbound trucks to arrive at the
border. At that time, they swap places with inbound drivers, and drive across the border.
This situation causes traffic disturbances as drivers walk between lanes and force trucks to
stop. This situation would be exacerbated if and when the POE inspection capability is
expanded to accommodate a higher throughput.1
1 A feasibility study and an environmental impact study have already been carried out with a view to a major
expansion of capacity at the Mariposa POE, but funding of construction has not yet occurred.
Bottleneck Study – Mariposa Port of Entry Page 7 of 212
(a) This situation should be resolved quickly since it contributes both to traffic congestion
and hazardous conditions.
(b) If this practice needs to be accommodated, a location can be established further south,
before the toll gate, to allow drivers to switch places safely.
Truck entrance to POE
High truck volumes were observed at the data collection point located before the
Mariposa POE where northbound trucks enter shortly before the inspection station closes. This
traffic might arrive from Mexican Customs in just enough time to reach the border before
inspections cease for the day. Expanded hours of service, announced on Oct. 7, 2008, may ease
this bottleneck.
Confederation of Agricultural Associations of the State of Sinaloa (CAADES) Facility
The CAADES facility located close to Mexican Customs had trucks stopping nearby for
quality grading, agricultural inspections and other services before departing for the POE. In
some cases drivers leave containers (both empty and full) on the sides of the road for other
drivers to pick up. This situation causes a large bottleneck for trucks going into the CAADES
facility and onto the Fiscal Corridor. Some improvements reportedly have been made since the
data collection period.
Bottleneck Study – Mariposa Port of Entry Page 8 of 212
We would like to express our gratitude to several individuals who provided invaluable assistance
for this study:
Rudy Perez, Arizona-Mexico Liaison, Arizona Department of Transportation, for giving us the
opportunity to conduct this important research
Jose Andres Sierra Hernandez, Director General, and Pablo de la Peña Sánchez, Director de Graduados y
Extensión, Instituto Tecnológico y de Estudios Superiores de Monterrey (ITESM), Campus Sonora Norte,
for facilitating the partnership between our universities
Terry Shannon, Jr., Chairman, Greater Nogales and Santa Cruz County Port Authority, for generously
sharing his insights and time
Fernando Lam Koerdell, Coordinador General de Proyectos Especiales, Secretaría de Infraestructura y
Desarrollo Urbana, Mexican State of Sonora, for arranging a stakeholders meeting in Hermosillo
Jesus Cruz, Chief, U.S. Customs and Border Protection, Nogales, Arizona, for graciously giving a tour of
the Mariposa Port of Entry facilities
Sylvia Grijalva, US-Mexico Border Planning Coordinator, Federal Highway Administration, for her
valuable comments throughout this process
Armando Goncalvez, Tucson Field Operations Office, U.S. Department of Homeland Security, for
providing timely traffic data
Anthony Kleppe, Assistant Manager, General Services Administration, for providing information on the
Mariposa Port of Entry redesign
Martha Rascon, SunFed and Greater Nogales and Santa Cruz County Port Authority, for providing access
to the Fiscal Corridor Working Group and her knowledge about the Corridor
Arnold Maltz, Associate Professor of Supply Chain Management, Arizona State University, for sharing
previous reports on the Port of Entry
Tom Martinez and Doug Kratina for providing valuable field assistance and instructions on the proper
methods of placing pneumatic tube counters
Arizona Department of Transportation engineers Jerry James, P.E., Resident Engineer, James F. Gomes,
Jr., Engineer In Training as well as to Transportation Engineering Specialist Manuel Bonorand, and
University of Arizona intern Monica Soto, for their assistance in providing cost estimates and the Nogales
site survey.
Brenda Bustillos and Eric Nava at the DynusT Laboratory at the Dept. of Civil Engineering and
Engineering Mechanics, University of Arizona, for leading the organization and execution of the data
collection in collaboration with Instituto Tecnológico y de Estudios Superiores de Monterrey (ITESM).
Dr. Mark Hickman, Department of Civil Engineering and Engineering Mechanics, Advanced Traffic and
Logistics Algorithms and Systems (ATLAS) Research Center, University of Arizona for assisting with
data collection using airborne cameras.
Mina Goldberg, for her many contributions to this report's content and editing
Lourdes Gonzalez and Christopher Basaldu, for their assistance in the early stages of this project
All the members of the Technical Advisory Committee and Stakeholders Group for their
invaluable advice and comments.
And most importantly, to the students from the University of Arizona and ITESM who collected
the data that made this study possible.
Bottleneck Study – Mariposa Port of Entry Page 9 of 212
1.1 Description and history of Mariposa Port of Entry (POE) ......................................................... 26
1.2 Recent and proposed improvements ........................................................................................... 36
1.3 Review of existing studies including CyberPort Study and Mariposa POE Feasibility Study ... 39
1.4 Stakeholder Meetings ................................................................................................................. 42
1.5 Study Objectives ......................................................................................................................... 43
2.1 Descriptions of Mariposa POE System ...................................................................................... 44
2.2 Study Scope ............................................................................................................................... 46
3.1 Study Framework ....................................................................................................................... 49
3.2 Data Collection ........................................................................................................................... 49
3.3 Bottleneck Identification ............................................................................................................ 50
3.4 Congestion Mitigation Strategies ............................................................................................... 50
4.1 Planning for Data Collection ...................................................................................................... 52
4.1.1 Nogales, Arizona, U.S. ............................................................................................... 52
4.1.2 Nogales, Sonora, Mexico............................................................................................ 53
4.2 Traffic Data Collection ............................................................................................................... 55
4.2.1 Nogales, Arizona, U.S. ............................................................................................... 55
4.2.2 Nogales, Sonora, Mexico............................................................................................ 60
4.3 Summary .................................................................................................................................... 61
5.1 Bottlenecks in Nogales, Arizona ................................................................................................ 62
5.1.1 Analysis of tube counter data ..................................................................................... 62
5.1.2 Intersection Delay Analysis ........................................................................................ 66
5.1.3 Travel time analysis from license plate data .............................................................. 71
5.2 Bottlenecks in Nogales, Sonora, Mexico .................................................................................... 79
Bottleneck Study – Mariposa Port of Entry Page 10 of 212
6.1 Local and short-term improvements ........................................................................................... 83
6.2 Long-term improvements ........................................................................................................... 91
Appendices ...................................................................................................................................94
7.1 Nogales, Arizona. U.S. ............................................................................................................... 94
7.1.1 Pneumatic Tube Count Datasets ................................................................................ 94
7.1.2 Intersection Traffic Volumes .................................................................................... 109
7.1.3 Delay Analysis .......................................................................................................... 121
7.2 Nogales, Sonora, Mexico .......................................................................................................... 123
9.1 Nogales, Arizona. USA. ........................................................................................................... 127
9.1.1 Pneumatic Tube Count Datasets .............................................................................. 127
9.1.2 Intersection Traffic Volumes .................................................................................... 146
9.1.3 Delay Analysis .......................................................................................................... 178
9.2 Nogales, Sonora. Mexico. ......................................................................................................... 183
9.2.1 Manual Traffic Counts ............................................................................................. 183
9.3 Delay analysis at Intersections .................................................................................................. 191
9.3.1 Day 1 ........................................................................................................................ 191
9.3.2 Day 2 ........................................................................................................................ 193
9.4 Delay Analysis from License Plate Datasets ............................................................................ 195
9.4.1 Travel Time before Mariposa Port of Entry ............................................................ 195
9.4.2 Travel Time including Inspection ............................................................................. 196
9.4.3 Travel time after an inspection ................................................................................. 200
Bottleneck Study – Mariposa Port of Entry Page 11 of 212
10 Technical Advisory Committee ..........................................................................................202
Bottleneck Study – Mariposa Port of Entry Page 12 of 212
Table 1-1 - Trade by Truck through Nogales, AZ ....................................................................... 28
Table 3-1 Existing and Predicted Traffic Through Mariposa POE (Louis Berger Group and
Performa, 2007) ................................................................................................................ 51
Table 5-1 Density Ranges for Level of Service ............................................................................ 62
Table 5-2 - Level of Service at ATb1 (day1) ................................................................................ 64
Table 5-3 – Level of Service at ATb1 (day2) ............................................................................... 64
Table 5-4 – Level of Service at ATb2 (day1) ............................................................................... 64
Table 5-5 – Level of Service at ATb2 (day2) ............................................................................... 65
Table 5-6 – Level of Service at ATb3 (day1) ............................................................................... 65
5-7 – Level of Service at ATb3 (day2) ......................................................................................... 65
Table 5-8 – Level of Service at ATb4 (day1) ............................................................................... 66
Table 5-9 – Level of Service at ATb4 (day2) ............................................................................... 66
Table 5-10 Camcorder collection points matching sets ................................................................ 73
Table 5-11 – Matching sets including POE inspection time ......................................................... 77
Table 6-1 - Cost estimation for addition of second left-turn lane at Mariposa and I-19 .............. 86
Table 6-2 Cost estimation for signal coordination for Baffert Dr/N Grand Ave.and W Mariposa
Rd./N Grand Ave .............................................................................................................. 88
Table 6-3 - Cost estimation for addition of right turn lane at Grand Ave. and Mariposa Lengthen 150' ..... 89
Table 9-1 - Matching sets including inspection time .................................................................. 196
Bottleneck Study – Mariposa Port of Entry Page 13 of 212
Figure 1-1 - Cross-Border Roads at Mariposa POE ..................................................................... 32
Figure 1-2 - Mariposa POE Compound ....................................................................................... 33
Figure 1-3 - Mariposa POE before construction of FAST lanes and new ADOT inspection station
.......................................................................................................................................... 38
Figure 2-1 - Nogales, Arizona (U.S.), Traffic Network and Mariposa POE (Courtesy of ADOT)
.......................................................................................................................................... 45
Figure 2-2 - Nogales, Sonora (Mexico), Traffic Network and Mariposa POE ............................. 46
Figure 3-1 - Research Framework ................................................................................................ 49
Figure 4-1 - Nogales, Arizona, Data Collection Locations .......................................................... 53
Figure 4-2 - Nogales, Sonora, Data Collection Locations ............................................................ 54
Figure 4-3 - Aerial View: Location and Direction for Intersection 1 Data Collection ................ 56
Figure 4-4 - Aerial View: Location and Direction for Intersection 2 Data Collection ................ 56
Figure 4-5 - Aerial View: Location and Direction for Intersection 3 Data Collection ................ 57
Figure 4-6 - Aerial View: Location and Direction for Intersection 4 Data Collection ................ 57
Figure 4-7 - Aerial View: Location and Direction for Intersection 5 Data Collection ................ 58
Figure 4-8 - Aerial View: Location and Direction for Intersection 6 Data Collection ................ 58
Figure 4-9 - Aerial View: Location and Direction for Intersection 7 Data Collection ................ 59
Figure 4-10 - Aerial View: Location and Direction for Intersection 8 Data Collection .............. 59
Figure 5-1 - Nogales, Arizona, Data Collection Locations .......................................................... 63
Figure 5-2 – Total delay and average delay (day1) ...................................................................... 67
Figure 5-3 –Delay at AInt 5 (Frank Reed) from AInt 6 (Industrial Park Dr.) (day1) ................... 68
Figure 5-4 ��Delay at AInt5 (Frank Reed) from AInt6 (Industrial Park Dr.) (day2) ..................... 68
Figure 5-5 – Delay at AInt4 (I-19 SB Ramp) from AInt5 (Frank Reed) (day1) .......................... 69
Figure 5-6 – Delay at AInt4 (I-19 SB Ramp) from AInt5 (Frank Reed) (day2) .......................... 69
Figure 5-7 – Delay at AInt3 (I-19 NB Ramp) from AInt 4 (I-19 SB Ramp) (day1) .................... 70
Figure 5-8 – Delay at AInt3 (I-19 NB Ramp) from AInt 4 (I-19 SB Ramp) (day2) .................... 70
Bottleneck Study – Mariposa Port of Entry Page 14 of 212
Figure 5-9 – Delay at AInt 2 (Grand Ave.) from ATb 2 (Mariposa Rd.) (day1) .......................... 71
Figure 5-10 – Delay at AInt 2 (Grand Ave.) from ATb 2 (Mariposa Rd.) (day1) ........................ 71
Figure 5-11 - Nogales, Sonora, Data Collection Locations .......................................................... 72
Figure 5-12 - Nogales, Arizona, Data Collection Locations ........................................................ 73
Figure 5-13 – Travel time from MCam 1 to MCam 2 (day1) ....................................................... 75
Figure 5-14 – Travel time from MCam 1 to MCam 2 (day2) ....................................................... 75
Figure 5-15 – Average travel time by hour of day (day1) ............................................................ 76
Figure 5-16 – Average travel time by hour of day (day2) ............................................................ 76
Figure 5-17 – Travel time distribution (day1) .............................................................................. 76
Figure 5-18 – Travel time distribution (day2) ............................................................................. 76
Figure 5-19 – POE inspection time by hour of day ...................................................................... 78
Figure 5-20 – Averaged POE inspection time by hour of day ...................................................... 78
Figure 5-21 – POE inspection time distribution .......................................................................... 78
Figure 5-22 Traffic lanes taken by vehicles before the Port of Entry ........................................... 79
Figure 5-23 - Nogales, Sonora Data Collection Locations ........................................................... 80
Figure 6-1 - Available space underneath I-19 bridge next to the abutment, looking eastbound
(Courtesy: James Gomes, Jerry James, ADOT) ............................................................... 84
Figure 6-2 - Available space at right-side shoulder on W Mariposa Rd., looking eastbound
(Courtesy: James Gomes, Jerry James, ADOT) ............................................................... 84
Figure 6-3 - Cantilever sign structure at the study site (Courtesy: James Gomes, Jerry James,
Figure 6-4 - View of the intersection (Courtesy: James Gomes, Jerry James, ADOT) ................ 85
Figure 6-5 - N Grand Ave. looking SB at the W Mariposa Intersection (Courtesy: James Gomes,
Jerry James, ADOT) ......................................................................................................... 88
Figure 6-6 - Close-up view of the intersection (Courtesy: James Gomes, Jerry James, ADOT) . 88
Figure 6-7 - Summary of Recommendations ................................................................................ 90
Figure 6-8 - Summary of Recommendations (cont'd) .................................................................. 91
Figure 6-9 - I-19 access (frontage) road ....................................................................................... 92
Bottleneck Study – Mariposa Port of Entry Page 15 of 212
Figure 6-10 - I-19 Frontage Road between W Mariposa Rd. and N Apache Rd. ......................... 93
Figure 7-1 - Speed Volume Data (ATb11) ................................................................................... 95
Figure 7-2 - Speed Volume Data (ATb12) ................................................................................... 95
Figure 7-3 - Mean Speed Data (ATb11) ....................................................................................... 96
Figure 7-4 - Mean speed data (ATb12) ......................................................................................... 96
Figure 7-5 - Traffic volume data (ATb11) .................................................................................... 97
Figure 7-6 - Traffic volume data (ATb12) .................................................................................... 97
Figure 7-7 - Speed Volume Data (ATb21) ................................................................................... 99
Figure 7-8 - Speed Volume Data (ATb22) ................................................................................... 99
Figure 7-9 - Mean Speed Data (ATb21) ..................................................................................... 100
Figure 7-10 - Mean Speed Data (ATb22) ................................................................................... 100
Figure 7-11 - Traffic Volume Data (ATb21) .............................................................................. 101
Figure 7-12 - Traffic volume data (ATb22) ................................................................................ 101
Figure 7-13 - Speed Volume Data (ATb31) ............................................................................... 102
Figure 7-14 - Speed Volume Data (ATb32) ............................................................................... 103
Figure 7-15 - Mean Speed Data (ATb31) ................................................................................... 103
Figure 7-16 - Mean Speed Data (ATb32) ................................................................................... 104
Figure 7-17 - Traffic Volume Data (ATb31) .............................................................................. 104
Figure 7-18 - Traffic Volume Data (ATb32) .............................................................................. 105
Figure 7-19 - Speed Volume Data (ATb41) ............................................................................... 106
Figure 7-20 - Speed Volume Data (ATb42) ............................................................................... 106
Figure 7-21 - Mean Speed Data (ATb41) ................................................................................... 107
Figure 7-22 - Mean Speed Data (ATb42) ................................................................................... 107
Figure 7-23 - Traffic Volume Data (ATb41) .............................................................................. 108
Figure 7-24 - Traffic Volume Data (ATb42) .............................................................................. 108
Figure 7-25 - IntersectionDesign (AInt1) ................................................................................... 109
Figure 7-26 - Traffic Volume for 18 Wheeler(AInt11) .............................................................. 110
Bottleneck Study – Mariposa Port of Entry Page 16 of 212
Figure 7-27 - Traffic Volume (AInt11) ...................................................................................... 110
Figure 7-28 - Traffic Volume for 18 Wheeler(AInt12) .............................................................. 110
Figure 7-29 - Traffic Volume (AInt12) ...................................................................................... 110
Figure 7-30 - Intersection Design (AInt2) .................................................................................. 111
Figure 7-31 - Traffic Volume for 18 Wheeler(AIn-21) .............................................................. 111
Figure 7-32 - Traffic Volume (AInt21) ...................................................................................... 111
Figure 7-33 - Traffic Volume for 18 Wheeler(AInt22) .............................................................. 112
Figure 7-34 - Traffic Volume (AInt22) ...................................................................................... 112
Figure 7-35 - Intersection Design (AInt3) .................................................................................. 112
Figure 7-36 - Traffic Volume for 18 Wheeler(AInt31) .............................................................. 113
Figure 7-37 - Traffic Volume (AInt31) ...................................................................................... 113
Figure 7-38 - Traffic Volume for 18 Wheeler(AInt32) .............................................................. 113
Figure 7-39 - Traffic Volume (AInt32) ...................................................................................... 113
Figure 7-40 - Intersection Design (AInt4) .................................................................................. 114
Figure 7-41 - Traffic Volume for 18 Wheeler(AInt41) .............................................................. 114
Figure 7-42 - Traffic Volume (AInt41) ...................................................................................... 114
Figure 7-43 - Traffic Volume for 18 Wheeler(AInt42) .............................................................. 115
Figure 7-44 - Traffic Volume (AInt42) ...................................................................................... 115
Figure 7-45 - Intersection Design (AInt5) .................................................................................. 115
Figure 7-46 - Traffic Volume for 18 Wheeler(AInt51) .............................................................. 116
Figure 7-47 - Traffic Volume (AInt51) ...................................................................................... 116
Figure 7-48 - Traffic Volume for 18 Wheeler(AInt52) .............................................................. 116
Figure 7-49 - Traffic Volume (AInt52) ...................................................................................... 116
Figure 7-50 - Intersection Design (AInt6) .................................................................................. 117
Figure 7-51 - Traffic Volume for 18-Wheeler(AInt61) .............................................................. 117
Figure 7-52 - Traffic Volume (AInt61) ...................................................................................... 117
Figure 7-53 - Traffic Volume for 18-Wheeler(AInt62) .............................................................. 118
Bottleneck Study – Mariposa Port of Entry Page 17 of 212
Figure 7-54 - Traffic Volume (AInt62) ...................................................................................... 118
Figure 7-55 - Intersection Design (AInt7) .................................................................................. 118
Figure 7-56 - Traffic Volume for 18 -Wheelers(AInt71) .......................................................... 119
Figure 7-57 - Traffic Volume (AInt71) ...................................................................................... 119
Figure 7-58 - Traffic Volume for 18 -Wheelers(AInt72) .......................................................... 119
Figure 7-59 - Traffic Volume (AInt72) ...................................................................................... 119
Figure 7-60 - Intersection Design (AInt8) .................................................................................. 120
Figure 7-61 - Traffic Volume for 18-Wheeler(AInt81) .............................................................. 120
Figure 7-62 - Traffic Volume (AInt81) ...................................................................................... 120
Figure 7-63 - Traffic Volume for 18-Wheeler(AInt82) .............................................................. 121
Figure 7-64 - Traffic Volume (AInt82) ...................................................................................... 121
Figure 7-65 - Delay from AInt61 to AInt51 ............................................................................... 122
Figure 7-66 - Delay from AInt62 to AInt52 ............................................................................... 122
Figure 7-67 - Delay from AInt51 to AInt41 ............................................................................... 122
Figure 7-68 - Delay from AInt52 to AInt42 ............................................................................... 122
Figure 7-69 - Delay from AInt41 to AInt31 ............................................................................... 123
Figure 7-70 - Delay from AInt42 to AInt32 ............................................................................... 123
Figure 7-71 - Delay from ATb21 to AInt21 ............................................................................... 123
Figure 7-72 - Delay from ATb22 to AInt22 ............................................................................... 123
Figure 7-73 - Location 1, Day 1 (MCnt1) ................................................................................... 124
Figure 8-1 – Total delay between consecutive intersections ...................................................... 125
Figure 8-2 – The calculation of point delays .............................................................................. 126
Figure 9-1 - Speed and volume data (ATb-11) .......................................................................... 127
Figure 9-2 - Mean speed data (ATb-11) ..................................................................................... 128
Figure 9-3 - Traffic volume data (ATb-11) ................................................................................ 128
Figure 9-4 - Volume data per speed interval (ATb-11) ............................................................. 129
Figure 9-5 - Speed and volume data (ATb-21) .......................................................................... 130
Bottleneck Study – Mariposa Port of Entry Page 18 of 212
Figure 9-6 - Mean speed data (ATb-21) ..................................................................................... 130
Figure 9-7 - Traffic volume data (ATb-21) .............................................................................. 131
Figure 9-8 - Volume data per speed interval (ATb-21) ........................................................... 132
Figure 9-9 - Speed and volume data (ATb-31) .......................................................................... 132
Figure 9-10 - Mean speed data (ATb-31) .................................................................................. 133
Figure 9-11 - Traffic volume data (ATb-31) ........................................................................... 133
Figure 9-12 - Volume data per speed interval (ATb-31) ......................................................... 134
Figure 9-13 - Speed and volume data (ATb-41) ...................................................................... 135
Figure 9-14 - Mean speed data (ATb-41) ................................................................................. 135
Figure 9-15 - Traffic volume data (ATb-41) ............................................................................ 136
Figure 9-16 - Volume data per speed interval (ATb-41) .......................................................... 136
Figure 9-17 - Speed and volume data (ATb-12) ....................................................................... 137
Figure 9-18 - Mean speed data (ATb-12) ................................................................................. 138
Figure 9-19 - Traffic volume data (ATb-12) ............................................................................. 138
Figure 9-20 - Volume data per speed interval (ATb-12) ............................................................ 139
Figure 9-21 - Speed and volume data (ATb-22) ....................................................................... 140
Figure 9-22 - Mean speed data (ATb-22) .................................................................................. 140
Figure 9-23 - Traffic volume data (ATb-22) ............................................................................ 141
Figure 9-24 - Volume data per speed interval (ATb-22) .......................................................... 142
Figure 9-25 - Speed and volume data (ATb-32) ....................................................................... 142
Figure 9-26 - Mean speed data (ATb-32) ................................................................................... 142
Figure 9-27 - Traffic volume data (ATb-32) .............................................................................. 143
Figure 9-28 - Volume data per speed interval (ATb-32) ............................................................ 143
Figure 9-29 - Speed and volume data (ATb-42) ......................................................................... 144
Figure 9-30 - Mean speed data (ATb-42) ................................................................................... 145
Figure 9-31 - Traffic volume data (ATb-42) .............................................................................. 145
Figure 9-32 -Volume data per speed interval (ATb-42) ............................................................. 146
Bottleneck Study – Mariposa Port of Entry Page 19 of 212
Figure 9-33 - Traffic volume for Auto (AInt-11) ............................................................................... 147
Figure 9-34 - Traffic volume for Light Truck (AInt-11) .................................................................... 147
Figure 9-35 - Traffic volume for 18 wheeler (AInt-11) ....................................................... 147
Figure 9-36 - Traffic volume for all modes (AInt-11) ................................................................ 147
Figure 9-37 - Variable width graph for Auto (AInt-11) ........................................................ 148
Figure 9-38 - Variable width graph for Light Truck (AInt-11) .................................................. 148
Figure 9-39 - Variable width graph for 18 Wheeler (AInt-11) ................................................... 148
Figure 9-40 – Variable width graph (AInt-11) ........................................................................... 148
Figure 9-41 - Traffic volume for Auto (AInt-21) ...................................................................... 149
Figure 9-42 - Traffic volume for Light Truck (AInt-21) ..................................................... 149
Figure 9-43 - Traffic volume for 18 wheeler (AInt-21) ....................................................... 149
Figure 9-44 - Traffic volume (AInt-21) ..................................................................................... 149
Figure 9-45 - Variable width graph for Auto (AInt-21) ........................................................ 150
Figure 9-46 - Variable width graph for Light Truck (AInt-21) .................................................. 150
Figure 9-47 - Variable width graph for 18 Wheeler (AInt-21) ................................................... 150
Figure 9-48 - Variable width graph (AInt-21) ............................................................................ 150
Figure 9-49 - Traffic volume for Auto (AInt-31) ....................................................................... 151
Figure 9-50 - Traffic volume for Light Truck (AInt-31) ........................................................ 151
Figure 9-51 - Traffic volume for 18-wheelers (AInt-31) ..................................................... 151
Figure 9-52 - Traffic volume (AInt-31) ...................................................................................... 151
Figure 9-53 - Variable width graph for Auto (AInt-31) ......................................................... 152
Figure 9-54 - Variable width graph for Light Truck (AInt-31) ................................................... 152
Figure 9-55 -Variable width graph for 18-wheelers (AInt-31) .................................................... 152
Figure 9-56 - Variable width graph for all modes (AInt-31) ....................................................... 152
Figure 9-57 - Traffic volume for Auto (AInt-41) ........................................................................ 153
Figure 9-58 - Traffic volume for Light Truck (AInt-41) ........................................................ 153
Figure 9-59 - Traffic volume for 18-wheelers (AInt-41) ............................................................. 153
Bottleneck Study – Mariposa Port of Entry Page 20 of 212
Figure 9-60 - Traffic volume (AInt-41) ..................................................................................... 153
Figure 9-61 - Variable width graph for Auto (AInt-41) ........................................................ 154
Figure 9-62 – Variable width graph for Light Truck(AInt-41) .................................................. 154
Figure 9-63 –Variable width graph (AInt-41) ............................................................................ 154
Figure 9-64 – Variable width graph (AInt-41) ........................................................................... 154
Figure 9-65 - Traffic volume for Auto (AInt-51) ....................................................................... 155
Figure 9-66 - Traffic volume for Light Truck (AInt-51) .......................................................... 155
Figure 9-67 - Traffic volume for 18 wheeler (AInt-51) ........................................................ 155
Figure 9-68 - Traffic volume (AInt-51) ...................................................................................... 155
Figure 9-69 - Variable width graph for Auto (AInt-51) .............................................................. 156
Figure 9-70 - Variable width graph for Light Truck (AInt-51) ................................................... 156
Figure 9-71 - Variable width graph for 18 Wheeler (AInt-51) ....................................................... 156
Figure 9-72 – Variable width graph (AInt-51) ........................................................................... 156
Figure 9-73 - Traffic volume for Auto (AInt-61) ........................................................................ 157
Figure 9-74 - Traffic volume for Light Truck (AInt-61) ............................................................. 157
Figure 9-75 - Traffic volume for 18 wheeler (AInt-61) .............................................................. 157
Figure 9-76 - Traffic volume (AInt-61) ..................................................................................... 157
Figure 9-77 - Variable width graph for Auto (AInt-61) ............................................................. 158
Figure 9-78 -Variable width graph for Light Truck (AInt-61) ................................................... 158
Figure 9-79 - Variable width graph for 18 wheeler (AInt-61) ........................................................ 158
Figure 9-80 - Variable width graph for all modes (AInt-61) ....................................................... 158
Figure 9-81 - Traffic volume for Auto (AInt-71) ....................................................................... 159
Figure 9-82 - Traffic volume for Light Truck (AInt-71) ............................................................ 159
Figure 9-83 - Traffic volume for 18-wheelers(AInt-71) ............................................................. 159
Figure 9-84 - Traffic volume (AInt-71) ..................................................................................... 159
Figure 9-85 - Variable width graph for Auto (AInt-71) .............................................................. 160
Figure 9-86- Variable width graph for Light Truck (AInt-71) .................................................... 160
Bottleneck Study – Mariposa Port of Entry Page 21 of 212
Figure 9-87 - Variable width graph for 18 wheeler (AInt-71) ........................................................ 160
Figure 9-88 - Variable width graph for all modes (AInt-71) ....................................................... 160
Figure 9-89 - Traffic volume for Auto (AInt-81) ....................................................................... 161
Figure 9-90 Traffic volume for Light Truck (AInt-81) ............................................................. 161
Figure 9-91 - Traffic volume for 18-wheelers(AInt-81) ............................................................. 161
Figure 9-92 - Traffic volume for all modes (AInt-81) ............................................................... 161
Figure 9-93 - Variable width graph for Auto (AInt-81) ............................................................. 162
Figure 9-94 - Variable width graph for Light Truck (AInt-81) .................................................. 162
Figure 9-95 - Variable width graph for 18 wheeler (AInt-81) ........................................................ 162
Figure 9-96 - Variable width graph for all modes (AInt-81) ....................................................... 162
Figure 9-97 - Traffic volume for Auto (AInt-12) ....................................................................... 163
Figure 9-98- Traffic volume for Light Truck (AInt-12) ............................................................. 163
Figure 9-99 -Traffic volume for 18-wheelers (AInt-12) ............................................................. 163
Figure 9-100 - Traffic volume for all modes (AInt-12) .............................................................. 163
Figure 9-101 - Variable width graph for Auto (AInt-12) ............................................................ 164
Figure 9-102 - Variable width graph for Light Truck (AInt-12) ................................................. 164
Figure 9-103 - Variable width graph for 18 wheeler (AInt-12) ...................................................... 164
Figure 9-104 - Variable width graph for all modes (AInt-12) ..................................................... 164
Figure 9-105 - Traffic volume for Auto (AInt-22) ..................................................................... 165
Figure 9-106 - Traffic volume for Light Truck (AInt-22) ........................................................... 165
Figure 9-107 - Traffic volume for 18-wheelers (AInt-22) .......................................................... 165
Figure 9-108 - Traffic volume for all modes (AInt-22) .............................................................. 165
Figure 9-109 - Variable width graph for Autos (AInt-22) .......................................................... 166
Figure 9-110 - Variable width graph for 18-wheelers (AInt-22) ................................................. 166
Figure 9-111 - Traffic volume for Autos (AInt-32) .................................................................... 166
Figure 9-112 - Traffic volume for Light Truck (AInt-32) ........................................................... 166
Figure 9-113 -Traffic volume for 18-wheelers (AInt-32) ............................................................ 167
Bottleneck Study – Mariposa Port of Entry Page 22 of 212
Figure 9-114 - Traffic volume for all modes (AInt-32) .............................................................. 167
Figure 9-115 - Variable width graph for Autos (AInt-32) .......................................................... 167
Figure 9-116 - Variable width graph for Light Trucks (AInt-32) ............................................... 167
Figure 9-117 - Variable width graph for 18-wheelers (AInt-32) .................................................... 168
Figure 9-118 - Variable width graph for all modes (AInt-32) ..................................................... 168
Figure 9-119 - Traffic volume for Autos (AInt-42) .................................................................... 168
Figure 9-120 - Traffic volume for Light Trucks (AInt-42)......................................................... 168
Figure 9-121 - Traffic volume for 18-wheelers (AInt-42) .......................................................... 169
Figure 9-122 - Traffic volume for all modes (AInt-42) .............................................................. 169
Figure 9-123 - Variable width graph for Autos (AInt-42) ........................................................... 169
Figure 9-124 - Variable width graph for Light Trucks (AInt-42) ............................................... 169
Figure 9-125 - Variable width graph for 18-wheelers (AInt-42) .................................................... 170
Figure 9-126 - Variable width graph for all modes (AInt-42) ..................................................... 170
Figure 9-127 - Traffic volume for Auto (AInt-52) ..................................................................... 170
Figure 9-128 - Traffic volume for Light Truck (AInt-52) ........................................................ 170
Figure 9-129 - Traffic volume for 18 wheeler (AInt-52) ............................................................ 171
Figure 9-130 - Traffic volume for all modes (AInt-52) .............................................................. 171
Figure 9-131 - Variable width graph for Auto (AInt-52) ............................................................ 171
Figure 9-132 - Variable width graph for Light Truck (AInt-52) ................................................. 171
Figure 9-133 - Variable width graph for 18 wheeler (AInt-52) ...................................................... 172
Figure 9-134 - Variable width graph for all modes (AInt-52) ..................................................... 172
Figure 9-135 - Traffic volume for Auto (AInt-62) ..................................................................... 172
Figure 9-136 - Traffic volume for Light Truck (AInt-62) .......................................................... 172
Figure 9-137 - Traffic volume for 18 wheeler (AInt-62) ............................................................ 173
Figure 9-138 - Traffic volume for all modes (AInt-62) .............................................................. 173
Figure 9-139 - Variable width graph for Auto (AInt-62) ............................................................ 173
Figure 9-140 - Variable width graph for Light Truck (AInt-62) ................................................ 173
Bottleneck Study – Mariposa Port of Entry Page 23 of 212
Figure 9-141 - Variable width graph for 18 wheeler (AInt-62) ...................................................... 174
Figure 9-142 - Variable width graph for all modes (AInt-62) ..................................................... 174
Figure 9-143 - Traffic volume for Auto (AInt-72) ..................................................................... 174
Figure 9-144 - Traffic volume for Light Truck (AInt-72) .......................................................... 174
Figure 9-145 - Traffic volume for 18 wheeler (AInt-72) ............................................................ 175
Figure 9-146 - Traffic volume for all modes (AInt-72) .............................................................. 175
Figure 9-147 - Variable width graph for Auto (AInt-72) ............................................................ 175
Figure 9-148 - Variable width graph for Light Truck (AInt-72) ................................................. 175
Figure 9-149 - Variable width graph for 18 wheeler (AInt-72) ...................................................... 176
Figure 9-150 - Variable width graph for all modes (AInt-32) ..................................................... 176
Figure 9-151 - Traffic volume for Auto (AInt-82) ..................................................................... 176
Figure 9-152 - Traffic volume for Light Truck (AInt-82) .......................................................... 176
Figure 9-153 - Traffic volume for 18 wheeler (AInt-82) ............................................................ 177
Figure 9-154 - Traffic volume for all modes (AInt-82) .............................................................. 177
Figure 9-155 - Variable width graph for Auto (AInt-82) ............................................................ 177
Figure 9-156 - Variable width graph for Light Truck (AInt-82) ................................................ 177
Figure 9-157 - Variable width graph for 18 wheeler (AInt-82) ...................................................... 178
Figure 9-158 - Variable width graph for all modes (AInt-82) ..................................................... 178
Figure 9-159 - Delay from AInt 6 to AInt 5 (Day 1) ................................................................. 178
Figure 9-160 - Delay from AInt 5 to AInt 4 (Day 1) ................................................................. 179
Figure 9-161 - Delay from AInt 4 to AInt 3 (Day 1) .................................................................. 179
Figure 9-162 - Delay from ATb 2 to AInt 2 (Day 1) ................................................................. 180
Figure 9-163 - Delay from AInt 6 to AInt 5 (Day2) ................................................................... 181
Figure 9-164 - Delay from AInt 5 to AInt 4 (Day 2) ................................................................. 181
Figure 9-165 - Delay from AInt 4 to AInt 3 (Day 2) ................................................................. 182
Figure 9-166 - Delay from ATb B to AInt 2 (Day 2) ................................................................. 182
Figure 9-167 - Traffic volume data (MCnt-11) .......................................................................... 183
Bottleneck Study – Mariposa Port of Entry Page 24 of 212
Figure 9-168 - Traffic volume data (MCnt-21) .......................................................................... 183
Figure 9-169 - Traffic volume data (MCnt-31) .......................................................................... 184
Figure 9-170 - Traffic volume data (MCnt-41) .......................................................................... 184
Figure 9-171 - Traffic volume data (MCnt-51) .......................................................................... 185
Figure 9-172 - Traffic volume data (MCnt-61) .......................................................................... 185
Figure 9-173 - Traffic volume data (MCnt-71) .......................................................................... 186
Figure 9-174 - Traffic volume data (MCnt-81) .......................................................................... 186
Figure 9-175 - Traffic volume data (MCnt-12) .......................................................................... 187
Figure 9-176 - Traffic volume data (MCnt-22) .......................................................................... 187
Figure 9-177 - Traffic volume data (MCnt-32) .......................................................................... 188
Figure 9-178 - Traffic volume data (MCnt-42) .......................................................................... 188
Figure 9-179 - Traffic volume data (MCnt-52) .......................................................................... 189
Figure 9-180 - Traffic volume data (MCnt-62) .......................................................................... 189
Figure 9-181 - Traffic volume data (MCnt-72) .......................................................................... 190
Figure 9-182 - Traffic volume data (MCnt-82) .......................................................................... 190
Figure 9-183 - Point delay from AInt 6 to AInt 5 ( Day 1) ........................................................ 191
Figure 9-184 - Point delay from AInt 5 to AInt 4 ( Day 1) ........................................................ 191
Figure 9-185 - Point delay from AInt 4 to AInt 3 ( Day 1) ........................................................ 192
Figure 9-186 - Point delay from ATb 2 to AInt 2 ( Day 1) ........................................................ 192
Figure 9-187 - Point delay from AInt 6 to AInt 5 ( Day 2) ........................................................ 193
Figure 9-188 - Point delay from AInt 5 to AInt 4 ( Day 2) ........................................................ 193
Figure 9-189 - Point delay from AInt 4 to AInt 3 ( Day 2) ........................................................ 194
Figure 9-190 - delay from ATb 2 to AInt 2 ( Day 2) .................................................................. 194
Figure 9-191 - Travel time from MCam1 to MCam2 (day1) ..................................................... 195
Figure 9-192 - Travel time from MCam1 to MCam2 (day2) ..................................................... 195
Figure 9-193 - Average travel time from MCam1 to MCam2 ................................................... 196
Figure 9-194 - Average travel time from MCam1to MCam2 ..................................................... 196
Bottleneck Study – Mariposa Port of Entry Page 25 of 212
Figure 9-195 - Travel time from MCam1 to ACam2 ................................................................. 196
Figure 9-196 - Travel time from MCam1 to ACam4 ................................................................. 197
Figure 9-197 - Travel time from MCam2 to ACam2 ................................................................. 197
Figure 9-198 - Travel time from MCam2 to ACam4 ................................................................. 198
Figure 9-199 - Average travel time from MCam1 to ACam2 .................................................... 198
Figure 9-200 - Average travel time from MCam1 to ACam4 .................................................... 198
Figure 9-201 - Average travel time from MCam2 to ACam2 ....................................................... 198
Figure 9-202 - Average travel time from MCam2 to ACam4 .................................................... 198
Figure 9-203 - Travel time from MCam1 to ACam1 ................................................................. 199
Figure 9-204 Travel time from MCam2 to ACam1 .................................................................... 199
Figure 9-205 - Average travel time from MCam1 to ACam1 ........................................................ 200
Figure 9-206 - Average travel time from MCam2 to ACam1 ........................................................ 200
Figure 9-207 Travel time from ACam1 to ACam2 .................................................................... 200
Figure 9-208 Travel time from ACam1 to ACam3 .................................................................... 201
Figure 9-209 - Average travel time from ACam1 to ACam2 ..................................................... 201
Figure 9-210 - Average travel time from ACam1 to ACam3 ..................................................... 201
Bottleneck Study – Mariposa Port of Entry Page 26 of 212
1.1 Description and history of Mariposa Port of Entry (POE)
The Mariposa POE, located in Nogales, Santa Cruz County, is Arizona's busiest border
crossing. Located on the western side of Nogales approximately 1.5 miles from the central
business district, the Mariposa POE sits atop a small mesa on 43 acres owned by the U.S.
General Services Administration (GSA). Directly to the southeast is the City of Nogales,
Sonora, Mexico. Mariposa POE is the largest port of entry for Mexican fresh fruits and
vegetables and has a highly seasonal type of traffic that peaks in the winter months. Nogales,
Sonora, has a significant cluster of maquiladora activity, which contributes to the bi-directional
flow of truck traffic through the Mariposa POE (electronics, equipment, apparel, etc.). However,
the significant traffic patterns of the agricultural industry, a sector affected by optimal planting
and harvest times as well as by weather conditions, distinguish the Mariposa POE from other
ports of entry.2
Although primarily a commercial port, the Mariposa POE also handles traffic from
privately-owned vehicles (POVs) and pedestrian crossings. 3 Within the facility, federal
inspectors conduct pre-screening, primary and secondary inspections for commercial and non-commercial
vehicles, as well as bus and pedestrian inspections. In an annex belonging to the
State of Arizona and operated jointly by state and federal authorities, vehicle safety inspections
are conducted.
Access from Nogales, Arizona, is via State Route 189 (SR 189, also known as Mariposa
Rd.), which has an interchange with I-19 approximately 3.1 miles north of the border crossing.
Access from Nogales, Sonora, Mexico, is through a modern, eight-mile-long, six-lane highway,
called the Corredor Fiscal (the "Fiscal Corridor"), that connects to Mexican Highway 15 at its
south entrance. For POVs, there is also access from the Nogales, Sonora city center through a
connector and interchange with the Fiscal Corridor a few meters south of the Mariposa POE.
2 McLaren, Dawn, 2007. "The Mariposa Port of Entry at Nogales, Arizona: Development of a Forecasting Model for
Cargo Crossings," Arizona State University, L. William Seidman Research Institute.
3 Two additional POEs are located in downtown Nogales. The DeConcini POE serves private vehicles, pedestrians
and rail containers; and the Morley Gate is restricted to pedestrians. In 2003, the Mariposa POE accounted for only
14 percent of pedestrian crossings through all the Nogales POEs.
Bottleneck Study – Mariposa Port of Entry Page 27 of 212
The Mariposa POE opened for commercial traffic in 1976 and expanded to handle POVs
in 1983. Mirroring the growth of maquiladora assembly and manufacturing plants in Mexico
and the impetus to cross-border trade provided by the North American Free Trade Agreement
(NAFTA), the Mariposa POE has grown from a modest beginning to an important entry point
from Mexico into the U.S. In particular, the significant level of agricultural imports is a
distinctive feature of the Mariposa POE. Regional population growth, increased law
enforcement activities and national security requirements have all further contributed to the
demands on the Mariposa POE's capacities.
Originally designed to handle 400 trucks daily with an expected utility life of 25 to 30
years, the facility now handles up to 1,300 trucks a day during peak season.4 Since NAFTA came
into effect in 1994, the number of northbound commercial truck crossings per year has grown
from 190,000 to over 280,000 in 2006. These crossings have also increased greatly in terms of
value and weight. In 2007, the facility processed imports into the U.S. worth $8.4 billion with a
weight of 6.26 billion pounds. Currently, the Mariposa POE processes 6.1 percent of the total
value of imports from Mexico by truck.
4 U.S. Department of Transportation, Bureau of Transportation Statistics, Transborder Surface Freight Database
(which also includes Border Crossing/Entry Data, based on data from U.S. Department of Homeland Security, Customs and
Border Protection, OMR database). (The trade value figures for 1995 would total to 5582 instead of 5581. This slight
differencer is due to rounding. There is a comparable slight difference in the 2007 value figures for the same
See also Doyle, Gary, "Environmental Fatal Flaw Screening and International Regulatory Issues," August 2001,
p. 7. http://www.canamex.org/PDF/Environmental_and_International_Issues.pdf
Bottleneck Study – Mariposa Port of Entry Page 28 of 212
Table 1-1 - Trade by Truck through Nogales, AZ 5
Value in Millions of US Dollars by Truck through Nogales, Arizona
1995 2007 % Change 1995-2007
Total Trade Value by
Truck 5,581 13,253 137.45
Exports Value by Truck 2,372 4,827 103.53
Imports Value by Truck 3,210 8,425 162.51
Weight in Millions of Pounds by Truck through Nogales, Arizona
1995 2007 % Change 1995-2007
Imports Weight by Truck 2,298 6,258 172.36
Despite various operational and structural changes, delays remain routine with long
queues of trucks often waiting hours to enter the inspection facility. In the busy winter produce
season, lines have stretched up to two miles with five-hour waits. These delays are costly,
resulting in unpredictable deliveries, immobilized inventory, idle equipment, loss of income and
profit, diminished tax revenues, and increased pollution. Prolonged waits are particularly severe
for agricultural products that are highly perishable. Even when direct spoilage does not occur,
the product has a shorter shelf life when it reaches its destination. For passengers in POVs,
delays disrupt personal activities, particularly at holiday times.
Nature of Crossings
The Mariposa POE hours of operation for cargo are weekdays 8:00 a.m. to 7:00 p.m. and
Saturdays to 6:00 p.m. Since 2005, limited hours on certain Sundays have been added from
about mid-January to mid-April and sometimes during the grape harvesting season in July.
These hours were expanded so that trucks with produce that arrive too late for Saturday
processing do not have to remain idle until Monday morning. While the U.S. agencies at the
5 Source: U.S. Department of Transportation, Research and Innovative Technology Administration, Bureau of
Transportation Statistics, TransBorder Freight Data. In addition to trade through the Mariposa POE, there is trade by
rail that crosses in downtown Nogales. Trade by rail through Nogales in 2007 amounted to $4.8 million with exports
of $1.1 million and imports of $3.7 million.
Bottleneck Study – Mariposa Port of Entry Page 29 of 212
Mariposa POE will process any cargo during open hours, Mexican customs authorities have at
times limited their Sunday cargo processing to produce.6
Expanded seasonal hours of service were announced for the POE on Oct. 7, 2008:
"Beginning January 1, 2009, the hours of service at the Mariposa Commercial Facility will
expand by two hours per day with the closing time Monday through Friday extending to 9 p.m.
and Saturday extending to 6 p.m. The port will open on Sunday as needed based on peak
demand. This expansion of hours will extend through the produce season (approximately May
Produce Shipments
The Mariposa POE is the crossing point for 60 percent of all winter produce shipped
from Mexico to the U.S., including tomatoes, cucumbers, melons, and peppers. Weather
conditions in Mexico's produce-growing regions have a direct impact on the daily and seasonal
flow of traffic. In recent years, billions of pounds of fresh fruit and vegetables pass through the
facility annually for distribution in the U.S. and Canada. This traffic is highly seasonal; it
increases during November through May, peaking from January through March. In recent years,
the produce season has lengthened due to more greenhouse growing. Also, areas further from
the border that did not previously export to the U.S. are starting to do so now. Depending upon
where the demand is, this produce is often routed through the Mariposa POE.
In 2005, fresh fruits and vegetables through the Mariposa POE accounted for 4 billion
pounds in weight and $2 billion in value out of a total of 5.5 billion pounds and $7.5 billion,
leaving approximately 1.5 billion pounds and $5.5 billion for non-produce shipments. Non-produce
category includes canned or processed fruits and vegetables. Compared to measurement
by value, produce accounts for a disproportionately large share of northbound traffic when
measured by weight or number of truck trips.
During peak months, the facility processes up to 30,000 trucks per month, or 1,200 to
1,300 trucks daily. The seasonality effect can be demonstrated through the monthly value of
shipments. From June 2006 through May 2007, the monthly value of agricultural and non-agricultural
northbound goods through the Mariposa POE ranged from a low of $453,000 (June
2006) to a high of $880,000 (March 2007), with the March figure reflecting the high agricultural
6 http://www.cbp.gov/xp/cgov/toolbox/contacts/ports/az/2604.xml Mexican authorities have had variable Sunday
practices, e.g., in 2007, during the limited high-season Sunday hours, all goods were accepted but, in 2008, during
the limited high-season Sunday hours, only produce was considered eligible. What will be accepted in 2009 has not
yet been announced.
7 http://cbp.customs.gov/xp/cgov/newsroom/news_releases/10072008.xml
Bottleneck Study – Mariposa Port of Entry Page 30 of 212
season. For that same period, the value of all types of southbound goods was fairly steady at
$350,000 to $453,000 per month.
When Mexican packinghouses load a truck with produce, the growers submit information
regarding the trailer's contents to the U.S. importer, and the U.S. and Mexican customhouse
brokers. The brokers then prepare the documentation necessary for the product to cross the
border, which is usually submitted to U.S. Customs and Border Protection (CBP) by the U.S.
broker. However, much of the produce grading activity takes place in Mexico. The U.S.
Department of Agriculture (USDA) has issued marketing orders for a number of produce items.8
The Arizona Department of Agriculture, using USDA-approved inspectors, performs inspections
in Mexico for quality, size, and freshness, as well as mandating proper labeling.9 Inspections for
pests, pesticide residues and contaminants are performed at the Mariposa POE. In 2003,
responsibilities for USDA-mandated border inspection requirements and the coordination of food
inspection agencies were transferred from USDA to CBP.
Industrial Shipments
Mexico's maquiladora system, established in 1965, enables plants to assemble or
manufacture goods for export using duty-free imported inputs and includes other benefits. The
passage of NAFTA boosted the use of this option. In 2005, Sonora was home to 205
maquiladora plants10 with over 80,000 employees in a number of industries, with the heaviest
concentration in electronic and automobile equipment. Other significant sectors include
aerospace and medical devices.11 These plants provide a regular stream of northbound trucks
through the Mariposa POE as well as rail shipments through downtown Nogales. The
maquiladora sector utilizes large amounts of materials and supplies. Some of these flow
southbound from the U.S. for "just-in-time" manufacturing at the maquiladoras. As indicated
above, the 2005 northbound truck shipments through the Mariposa POE for goods other than
fresh produce amounted to approximately 1.5 billion pounds and $5.5 billion.
8 Marketing order are user-funded programs provide for product research and promotion, and often require quality
9 Arizona's Department of Agriculture has its own regulations, embodied in the Citrus, Fruit and Vegetable
Standardization Program.
10 Of these plants in the Mexican state of Sonora, 104 are located in the Nogales, Sonora, area as of 2007. Gabriella
Rico, Arizona Daily Star, April 24, 2007, p. 1.
11 U.S. Census Bureau, Foreign Trade Statistics. 2006b. USA Trade Online. http://www.usatradeonline.gov/
Bottleneck Study – Mariposa Port of Entry Page 31 of 212
Privately-owned Vehicles
The Mariposa POE processed over 1.2 million POVs from mid-2005 to mid-2006.12
Peak periods occur at holiday times (e.g., December – January) for shopping, family events and
related activities. Spring Break, Memorial Day weekend and three-day weekends also see spikes
in crossings by vacationers. However, crossing the border for shopping, business, tourism,
health services, schooling or visiting family and friends, is a common practice year-round. POV
and pedestrian processing hours are available seven days a week, 6:00 a.m. – 10:00 p.m., with
late service offered at holiday times, as traffic dictates.13
Ingress and Egress Roads
Southbound (U.S. Mexico)
From the U.S., the Mariposa POE is accessed via SR 189 (Mariposa Rd.). Beginning as
an exit off Interstate 19 (I-19) approximately 3.1 miles north of the border, this two-lane road
weaves through a commercial district on the outskirts of Nogales before ending at the Mariposa
Southbound commercial and passenger vehicles are checked by Mexican customs,
immigration and other authorities, but do not experience the long queues and delays common for
northbound commercial vehicles. Many southbound commercial vehicles are empty, and it is
important for them to be able to cross back into Mexico promptly to pick up a new load.
12 RTI International. June 2007. "The Economic Benefits of Expanding the Border-Crossing for Commercial
Vehicles at the Mariposa Crossing in Nogales," Prepared for Gary Becker, U.S. Department of Homeland Security,
Private Sector Office. Of these 1.2 million POVs, 72,000 were referred for secondary inspection.
13 http://www.cbp.gov/xp/cgov/toolbox/contacts/ports/az/2604.xml. In addition, in September 2008, CBP was
installing radio frequency identification (RFID) devices at the Mariposa POE to be used in conjunction with travel
documents required under the Western Hemisphere Travel Initiative (WHTI). WHTI requires all travelers to and
from Canada, Mexico, the Caribbean and Bermuda who have historically been exempt from passport requirements,
to present a passport or other approved document that establishes the bearer's identity and citizenship in order to
enter or re-enter the United States.
14 http://www.canamex.org/PDF/Environmental_and_International_Issues.pdf
Bottleneck Study – Mariposa Port of Entry Page 32 of 212
Figure 1-1 - Cross-Border Roads at Mariposa POE
Bottleneck Study – Mariposa Port of Entry Page 33 of 212
Northbound (Mexico ` U.S.)
1. Lanes (queues) before crossing the
physical border.
2. Pre-screening lanes and inspection
3. Primary inspection stations
4. Different quantities of docks at each side
of the main compound, where the detailed
inspection takes place.
5. X-Ray stations.
6. Inspection lanes in the ADOT yard.
7. Parking spaces at the ADOT yard.
Figure 1-2 - Mariposa POE Compound 15
For access from Mexico, the Fiscal Corridor, opened in 1999, is owned and operated by a
private concessionaire and is fenced-in to restrict access. The road was built to ease congestion
and expedite the flow of cross-border traffic towards the Mariposa POE. Previous to that, trucks
traveled on local roads through the City of Nogales, Sonora. A half mile after exiting
Highway 15, northbound vehicles arrive at the 20-acre Mexican customs station where truckers
file their export paperwork, separate from the facilities for declaring imported merchandise. The
Fiscal Corridor and customs station is monitored by long-range cameras.16 Immediately to the
south of this facility is the CAADES Station, which provides export and inspection services for
its members.17 At the CAADES facility, agricultural grading inspections are completed by third-party
inspectors contracted and certified through the Arizona Department of Agriculture.
15 J. René Villalobos, Arnold Maltz, Omar Ahumada, Gerardo Trevi��o, Octavio Sánchez, and Hugo C. García,
Logistics Capacity Study of the Guaymas-Tucson Corridor, Arizona State University Departments of Industrial
Engineering and Department of Supply Chain (a report to ADOT), 2006., p. 38.
16 http://www.nusd.k12.az.us/schools/nhs/gthomson.class/articles/truckers.gowest.html
17 La Confederación de Asociaciones Agrícolas del Estado de Sinaloa (Confederation of Agricultural Associations
of the State of Sinaloa - CAADES) was formed in 1932 to unite agricultural producers in the Sinaloa region. It
consists of 10 agricultural associations representing some 25,000 farmers, whose food production is responsible for
30% of the State of Sinaloa's gross domestic product. http://www.caades.org.mx/publico/principal/index.asp and
Bottleneck Study – Mariposa Port of Entry Page 34 of 212
After clearing customs, vehicles entering the Fiscal Corridor pay a toll.18 This is a sealed
road with barricades on either side to limit unauthorized incursions on the right-of-way, the
highway has no intermediate off-ramps and terminates at the entrance to the Mariposa POE. For
trucks leaving maquiladora plants located close to the border, the Fiscal Corridor is less direct
than the previous route, as they must drive south to access the toll road.
During peak season, long delays are common on the Fiscal Corridor as traffic approaches
the Mariposa POE. On February 14, 2007, truckers staged a spontaneous blockage of
commercial traffic to express their discontent with the newly initiated eManifest system, along
with frustrations with the overburdened infrastructure.19 The blockade, at the northern end of the
Fiscal Corridor, was dismantled after four days, at which time all lanes became northbound to
clear the congestion. Shortly thereafter, new lanes were added by using the shoulders of the
Another blockade took place during the 2008 high season, April 19-20 at the southern
part of the Fiscal Corridor. Truckers protested delays caused by a new policy that required all
trucks to be scanned by the single gamma ray machine available at the Mexican Customs facility.
The main purpose of this scan was to intercept drugs or weapons. In response to the protest,
Mexican Customs officials agreed to use random screening instead of requiring a 100%
Road network (number and direction of lanes)
Fiscal Corridor
As it approaches the border, the Fiscal Corridor divides into four northbound lanes for
different types of traffic: approved FAST Lane commercial vehicles (one lane), non-approved
commercial vehicles (two lanes), and POVs (one lane). The two right-hand lanes of the
18 The various toll charges in pesos as of September 2008 are:
Local Not Local
Cars and Motorcycles 27.00 pesos 37.00 pesos
3 Axles 53.00 75.00
4 to 5 Axles 133.00 133.00
6 to 9 Axles 152.00 152.00
Over 9 Axles 171.00 171.00
This charge is the same for both northbound and southbound trips. A truck coming to Nogales, Arizona, will pay
twice, once entering and once again leaving the Corridor.
19 The eManifest allows truckers to electronically file their cargos with CBP prior to crossing the border.
20 Written Testimony of Maria Luisa O'Connell, President of the the Border Trade Alliance, before the House
Homeland Security Subcommittee on Border, Maritime and Global Counterterrorism, July 26, 2007.
21 El Imparcial, April 22-24, 2007, Nogales section, published in Hermosillo, Mexico.
Bottleneck Study – Mariposa Port of Entry Page 35 of 212
northbound Fiscal Corridor are for the commercial vehicles not enrolled in FAST, the next lane
is for commercial vehicles using FAST, and the left-hand lane is for POVs.
Northbound Privately-owned Vehicles
Northbound POVs from the City of Nogales area access the Fiscal Corridor from a local
connector road, called the Donaldo Colosio Periférico, which leads to a two-lane on-ramp at the
northern end of the Fiscal Corridor. They then merge with the POV lane on the Fiscal
Corridor.22 After crossing the border, POVs move forward to the east side of the main building,
situated 700 feet from the border; the building has four POV primary inspection booths. A
follow-on area is available for any needed POV secondary inspection and is adjacent to a small
x-ray enclosure.
Commercial traffic
It is mandatory at all land border crossings, including the Mariposa POE, for a truck's
cargo manifest to be reported electronically to Customs and Border Protection (CBP) before the
truck's arrival at the port of entry. Cargo data are usually entered by brokers. The eManifest,
which is integrated with the CBP computer system used to track cargo, known as the Automated
Commercial Environment (ACE),23 includes information on the cargo, truck cab and trailer, and
the driver in addition to the product, importer, and exporter information.24
Northbound commercial traffic, moving into the Mariposa POE compound passes
between radiation detectors. Trucks then proceed to the pre-primary Drug Screening Area, a
shelter located outside the compound, where dogs sniff the queue for drugs. The shelter includes
platforms and catwalks that permit inspectors to inspect an entire truck. ADOT installed weigh-in-
motion scales at the immediate approach to the Drug Screening facility in order to pre-weigh
all incoming commercial vehicles.
Commercial vehicles entering the U.S. first pass through the pre-screening area, located
500 feet from the border. From there, four lanes lead to primary inspection, which consists of
four SuperBooths, each staffed with three people to deal with the requirements of several
agencies in one location (Customs, Food and Drug Administration [FDA], etc.) in the one
location plus an oversize lane. Finally, there are spaces available for secondary inspections,
which range from a brief assessment to the unloading of all cargo for 100% inspection.
22 The Periférico passes under the Fiscal Corridor and so approaches from the left of the northbound Fiscal Corridor.
23 http://www.cbp.gov/linkhandler/cgov/toolbox/about/modernization/ace_welcome/ace101.ctt/ace101.pdf
and http://cbp.gov/xp/cgov/toolbox/about/modernization/whats_new/survey_cbp_officers.xml
24 In addition to the potential in general for greater efficiency and effectiveness, this pre-notification rule is useful in
alerting officials when a shipment of hazardous materials is en route.
Bottleneck Study – Mariposa Port of Entry Page 36 of 212
The SuperBooths, where eManifests and any paperwork are reviewed, are located
separate from, and to the east of, the POV primary inspection booths. After pre-screening and
primary inspection, commercial vehicles may be either released or sent for a more thorough
secondary screening and/or x-ray inspection. Secondary inspections for trucks are performed at
a commercial inspection building surrounded by a pinwheel-shaped configuration of docks.
(The number of docks, however, do not correspond to the inspection capacity, i.e., the number of
trucks that can be accommodated at one time, as some docks are blocked by special-purpose
portable buildings and, thus, unavailable for secondary inspections.) Secondary inspection may
include hazardous materials and weapons inspection as well as other checks, such as for
narcotics and agricultural pests. Vehicles requiring an x-ray inspection go to x-ray stations,
located on the northern edge of the compound.
ADOT Station
On an adjacent site, state and federal vehicle inspections and driver checks for safety,
highway user fee compliance, etc., are conducted. The Mariposa State Motor Carrier Safety
Inspection Station is a two-story, two-bay building, operated jointly by federal and state
authorities.25 There are two approaching lanes from the POE compound as well as lanes that
lead out of the station directly to SR 189 (Mariposa Rd.) without returning through the POE. On
the north side of the station is a facility used as a place for out-of-service commercial vehicles as
well as for other vehicles that have drivers who have been disqualified for safety or other motor
carrier infractions.
1.2 Recent and proposed improvements
Over the past decade, the Mariposa POE underwent various improvements to
accommodate increasing traffic volume.26 The "SuperBooth" concept was implemented for
primary inspection with officials of different agencies sharing the same processing space, and a
bypass was constructed for commercial vehicles cleared in the primary inspection phase. Truck
x-ray capacity was added in 1999, reducing the need to unload suspicious cargo. A mobile
gamma x-ray unit was also installed that is of particular benefit for examining tanker vehicles.
Another improvement was the Commercial Vehicle Port Intelligent Transportation System,
known as EPIC (i.e., Expedited Processing at International Crossings).27
25 It houses inspection teams from the Arizona Department of Public Safety (Highway Patrol), ADOT's Motor
Vehicle Division (MVD) and the Federal Motor Carrier Safety Administration (FMCSA).
26 http://www.ers.usda.gov/publications/agoutlook/sep2000/ao274h.pdf and
27 For more about EPIC, see Section 2.1 of this report.
Bottleneck Study – Mariposa Port of Entry Page 37 of 212
In 1999, on the Mexican side, leading to the Mariposa POE from the south, the four-lane,
fenced, restricted-access, toll road, known as the Fiscal Corridor, was built. This road diverted
cross-border traffic toward the Mariposa POE and away from the DeConcini POE, located in
downtown Nogales, Arizona.
In 2000, land was acquired for building the ADOT commercial motor vehicle inspection
station. In 2003, a fourth SuperBooth was added. In early 2004, the new motor carrier
inspection station, on the U.S. side, gave state and federal inspectors one building to work from
while inspecting trucks and their drivers. A lane was added routing commercial vehicles to the
new station. The Mariposa State Motor Carrier Safety Inspection Station has itself undergone
some upgrades since it was built.
In December 2004, the Nogales and Santa Cruz County Port Authority was established to
represent the Nogales and Santa Cruz region. Present members include Santa Cruz County, City
of Nogales, Nogales Chamber of Commerce, Fresh Produce Association of the Americas,
Nogales U.S. Customs Brokers Association, Nogales Alliance, which consists of Port of the
Future, Nogales Community Development Corporation, and Santa Cruz Tourism Council. The
Port Authority organizes regular meetings to keep the public informed about various issues,
including the Mariposa POE and its future development. It has sought, inter alia, to have studies
commissioned to recommend road improvements to the Mariposa POE from the north. In 2008,
the Arizona Department of Transportation (ADOT) selected the firm of Wilbur Smith Associates
to study the possibility of a divided access connector road directly between the Mariposa POE
and I-19. This connector would facilitate the exit from the Mariposa POE, by enabling many
vehicles to avoid the commercial area they now traverse and to prevent delays that now occur at
the interchange as vehicles enter I-19. This study is expected to be completed in 2009.
One operational improvement instituted in 2005 added limited Sunday hours during the
peak agricultural period from mid-January to mid-April.
In the spring of 2006, the computer system used to track cargo was phased out in favor of
a new system that consolidates several databases into one. The new system allows officials to
obtain history about drivers, shipments and companies through one source. Nogales was one of
the first POEs to implement the new system called Automated Commercial Environment
In mid 2006, two Free and Secure Trade (FAST) lanes were added for use by carriers
who have been pre-qualified as trusted. FAST lanes allow expedited travel for pre-screened, low
risk trucks bringing products into the U.S. The cost of implementing the FAST lanes at the
28 http://www.cbp.gov/linkhandler/cgov/toolbox/about/modernization/ace_welcome/ace101.ctt/ace101.pdf
Bottleneck Study – Mariposa Port of Entry Page 38 of 212
Mariposa POE was approximately $4.3 million on the U.S. side plus costs incurred by Mexico of
about $1 million for connecting lanes on the Sonoran side. On the U.S. side, additional
commercial vehicle lanes were constructed to the east of the already existing lanes and allowed
flexibility to shift trucks among the four lanes according to demand. In 2007, two lanes were
added to the Fiscal Corridor on the Mexican side by making use of the shoulders on both sides of
the highway. The result was six narrow lanes, two southbound and four northbound.29 In these
new lanes, passing is difficult, but nevertheless frequent.
Figure 1-3 - Mariposa POE before construction of FAST lanes and new ADOT inspection station30
1. Border 2. Document distribution 3. USDOT inspection 4. Weigh-in-Motion 5. Drug and weapons
screening 6. Primary/superbooths 7. Personal vehicle entries 7a. Primary entry 7b. Secondary entry
8. Flow into secondary inspection 9. Secondary inspections 9a U.S. Department of Agriculture
9b Intensive inspections 9c. Brokers 10. X-ray, VACIS 11. Primary exit 12. Secondary exit
The FAST lanes are based on the Customs-Trade Partnership Against Terrorism
(C-TPAT), a public-private partnership for commercial carriers that includes background checks
and other requirements. CBP's FAST program enables certified commercial vehicles to cross
the border using faster-moving lanes and experiencing fewer inspections. In exchange for
shorter wait times and less scrutiny at the border, the companies must meet minimum security
29 Truckers had blocked the area where the Fiscal Corridor approaches the border to protest glitches related to new
U.S. computerization, but also noted that they could not access benefits from the U.S. FAST lanes unless there were
connecting "fast" lanes on the Mexican side.
30 Cyberport Study. (2003). P. 143.
Bottleneck Study – Mariposa Port of Entry Page 39 of 212
guidelines outlined by CBP.31 FAST clearance can be used only if an approved driver carries
eligible goods for an approved carrier, importer and shipper.
In January 2007, it became mandatory for a truck's cargo manifest to be reported
electronically to CBP before the truck arrives at land border crossings. The Mariposa POE was
one of the earliest border crossings where this operational improvement was implemented.32
After a feasibility study completed in May 2005, $13.69 million was appropriated in the
Fiscal Year 2007 (FY 2007) federal budget for the design phase of a complete state-of-the-art
reconfiguration and modernization of the Mariposa POE. This work is virtually complete. An
environmental assessment has already been carried out and the draft circulated for public
comment. 33 It was anticipated by officials and the affected communities that substantial
additional funding (approximately $170 million) would be requested in the General Services
Administration's Federal Building Fund appropriation for FY 2009 in order to go forward with
construction. The expected target date for completing construction was to be 2011, with
construction being done in phases so that the Mariposa POE could remain in operation.
However, the President's budget request for FY 2009 omitted any funds for this construction,
putting any further action on hold.34 On the Mexican side, design work has begun on increases
in capacity needed there to complement the increased capacity that is planned for the U.S. side.
1.3 Review of existing studies including CyberPort Study and Mariposa POE
Feasibility Study
The Mariposa Port of Entry (POE) has been studied a number of times in recent years,
both as a main subject and as part of regional or statewide analysis. Nearly all of these previous
studies commented on congestion at the border and the variability35 of traffic at the Mariposa
31 http://cbp.customs.gov/linkhandler/cgov/import/commercial_enforcement/ctpat/fast/us_mexico/mexico_fast.ctt/mexico_fast.doc
32 Code of Federal Regulations, Title 19, Part 123.92 (19 CFR 123.92). This regulation requires that advance
electronic cargo information, in the form of an eManifest, be provided to CBP one hour (for FAST lanes, thirty
minutes) prior to the arrival of the conveyance at the U.S. port of arrival.
33 Federal Register, Vol. 72, No. 192, October 4, 2007, p. 56763
34 Budget of the United States Government, Fiscal Year 2009—Appendix, General Services Administration.
http://www.whitehouse.gov/omb/budget/fy2009/pdf/appendix/gsa.pdf The FY 2009 Budget is expected to be
considered in Congress in January 2009. In order not to lose a year, some have recommended that, if necessary,
instead of the usual practice of appropriating the full amount for a major project (in this instance over $170 million),
a first installment of $20 million for the groundwork be made available in FY 2009. Further construction would
then depend upon future year appropriations.
35 By season, time of day and day of the week.
Bottleneck Study – Mariposa Port of Entry Page 40 of 212
POE. Some highlight the significance of bi-directional flows through the Mariposa POE to the
development of the CANAMEX Trade Corridor.36
Earlier reports on the Mariposa POE include the Arizona Port Efficiency Study (1997)
and the Arizona Trade Corridor Study (1999). The Arizona Port Efficiency Study recommended
bilingual signs, installation of elevated SuperBooths, cross-training of inspectors on requirements
of other border agencies, and other steps to promote efficiency within the POE compound.37 On
a border-wide level, a U.S. General Accounting Office (GAO) study, the U.S.-Mexico Border:
Better planning needed to handle growing commercial traffic (2000), mentioned Nogales and
commented, with respect to POEs in general, on difficulties resulting from multiple checks by
various federal and state agencies as well as the lack of land for POE expansion.
Intelligent Transportation Systems at International Borders (2001)38, prepared by the U.S.
Federal Highway Administration and U.S. Transit Administration, covered the larger POEs at
the northern and southern U.S. borders. With respect to Nogales, the report noted the importance
of fresh produce shipped in the winter months and the value in Nogales of maquiladora trade.
The report commented on the cooperation between U.S. and Mexican officials, reviewed existing
technologies and recommended further consideration of technologies for vehicle identification,
status and operating condition. Another overall study, Truck Transportation Through Border
Ports of Entry: Analysis of Coordination Systems (2002)39, urged greater coordination at POEs
among the numerous stakeholders, such as federal agencies, shippers, carriers, brokers, etc.
Other studies looked at Arizona and the Mexican State of Sonora as a region. Some
recommended investment in the Port of Guaymas in Sonora to supply the Mexican market and to
serve as an alternative to congested port facilities on the U.S. west coast.40 This prospect, still
under serious consideration, faces several obstacles, including shallow draft and a low level of
outbound cargo as indicated in Arizona's Global Gateway: Addressing the Priorities of Our
36 http://www.canamex.org/publications.asp . CANAMEX was designated by the U.S. Congress in 1995 as a High
Priority Corridor and is still being developed. The designation was under the National Highway Systems
Designation Act. This U.S. north-south corridor starts from Nogales, Arizona, and goes through Las Vegas, Nevada,
to Salt Lake City, Utah, to Idaho Falls, Idaho, to Montana, to the Canadian border. At the north and south ends of
the CANAMEX Corridor, Canadian and Mexican roads lead, respectively, into Alberta and toward Mexico's
western ports.
37 Conducted by TransCore in cooperation with Science Applications International Corporation (SAIC) and the
National Law Center for Inter-American Free Trade. 1997.
38 http://www.itsdocs.fhwa.dot.gov/jpodocs/repts_te/11490.pdf
39 Mark I.Ojah Juan Carlos Villa, William R. Stockton, P.E., David M. Luskin, and Rob Harrison, Texas
Transportation Institute, The Texas A&M University System, 2002.
40 The port of Guaymas could perhaps also be useful for shipments from points of origin on the west coast of South
America as a route to the U.S. mid-west rather than through the Panama Canal to the U.S. east coast.
Bottleneck Study – Mariposa Port of Entry Page 41 of 212
Border Communities (2003), sponsored by the Arizona Mexico Commission.41 A more recent
study, Logistics Capacity Study of the Guaymas-Tucson Corridor (2006)42 pointed out the need
for cranes on the dock or on the arriving ship, and concluded that minor improvements could
allow container service to start at Guaymas.
The Nogales CyberPort Project: Comprehensive Report (2003) explored options for
further improving the efficiency and increasing the throughput by means of changes in processes
and increased use of technology.43 The CyberPort Report recommended operational principles,
structural features, roadway improvements and possible off-site activities as part of an overall re-design.
The study noted that trade-flow volumes through the Mariposa POE are more highly
subject to variation with respect to time of day, day of the week and season of the year than any
other border POEs. Other sources indicate that Wednesdays and Thursdays during the peak crop
season tend to be the busiest. Recommendations included a flexible staffing that allowed for
allocation of human resources to accommodate changes in demand throughout the day, week,
and season. Pre-payment and pre-issuance arrangements for fees and permits were also proposed.
Federal funding related to the CyberPort concept financed the construction of two Free
and Secure Trade (FAST) lanes at the Mariposa POE and a feasibility study for the facility's
total re-design. These are brick-and-mortar projects that would incorporate a number of
technological improvements consistent with the CyberPort concept.
The CyberPort Report also recommended that the Mariposa POE be designated as a
national pilot test site for implementation of new technologies and procedures. While not
formally designated, the Mariposa POE has served as a test bed for new methods to measure
vehicle emissions and scenarios to inform officials who find that a vehicle registered positive for
radiation. In 2005, the U.S. Environmental Protection Agency funded a test of air pollution
emissions from trucks along the U.S.-Mexico border near Nogales, Arizona, this effort was
supported by the Mexican and Arizonan environmental agencies. Testing was performed using
drive-by ultraviolet/infrared, onboard, and tailpipe devices. It was found that diesel emissions
from the increasing number of trucks at the border crossing can present a significant public
41 Deeper water exists nearby, but would require substantial investment to develop.
42 J.René Vilalobos, Amold Maltz, Omar Ahumada, Gerardo Treviño, Octavio Sánchez, and Hugo C. García,
Arizona State University Department of Industrial Engineering and Department of Supply Chain (a report to
ADOT). http://tpd.azdot.gov/planning/Files/guaymas/FinalReport_%20English.pdf
43 "Expanding Trade throught Safe and Secure Borders" (hereinafter "CyberPort Study"). 2003. Commissioned by
the Governor's CANAMEX Task Force sponsored by the Arizona Department of Transportation and conducted by
the University of Arizona Office of Economic Development.
http://tpd.azdot.gov/reports/pdf/UAE3003cyberrtexecrep.pdf and
Bottleneck Study – Mariposa Port of Entry Page 42 of 212
health risk to residents on both sides of the border. The report, issued in 2006, recommended
looking into new and emerging technologies and fuels.44
In 2005, the U.S. General Services Administration (GSA) conducted a feasibility study of
the Mariposa POE to examine the requirements, costs and benefits of a number of expansion
options.45 Based on traffic projections through 2020, the study put forward several alternatives,
including the preferred one that proposed a transformed Mariposa POE with increased capacity
and that the POE be designed so as to allow some further expansion if the forecasts for 2020
prove too conservative. The study proposal includes an increase of POV processing slots from
four to six for primary inspection and from eight to 16 for secondary inspections. Commercial
primary inspection booths would increase to six with an expansion capacity to eight, and
pedestrians' primary processing would go from one to three physical positions. Funds were
appropriated for the design phase but, as noted above (Section 1.2), funding for construction has
not been made available so far.
The Economic Benefits of Expanding the Border-Crossing for Commercial Vehicles at
the Mariposa Crossing in Nogales (2007) analyzed the cost of freight traffic delays to directly
affected industries (logistics providers, shippers and their customers, etc.) as well as the indirect
cost to the related local, regional and national economies and additional environmental costs
associated with air pollution with respect to repairing damage and providing for prevention.46
This study calculated direct, indirect and induced benefits of reducing delays and added that
faster throughput of trade could, over time, also mean more investment in the region and a
further increase in trade.
1.4 Stakeholder Meetings
A series of sessions was held with Mariposa POE stakeholders to elicit their perspectives
on POE bottlenecks and congestion. These meetings served to elicit anecdotal information about
the facility and its operations, to determine what the stakeholders considered as the boundaries
for this study and to discuss related changes and challenges that have occurred over recent years.
There were five stakeholders sessions: (1) an initial meeting in Tucson, with Arizona and
Sonoran stakeholders to launch the project, (2) a second one to present the initial findings, (3) a
44 http://www.epa.gov/ocem/gneb/gneb9threport/English-GNEB-9th-Report.pdf. E.g., advanced engines in newer
trucks can make use of Ultra Low Sulfur Diesel (ULSD) and produce significantly lower emissions.
45 "Feasibility Study: Mariposa US Port of Entry, Nogales, Arizona." May 2005. Prepared for Arizona Department
of Transportation and U.S. General Services Administration. Prepared by Kimley-Horn and Associates and BPLW
Architects Engineers, Inc.
46 RTI International. June 2007. Prepared for Gary Becker, U.S. Department of Homeland Security, Private Sector
Office. Op. cit.
Bottleneck Study – Mariposa Port of Entry Page 43 of 212
meeting in Nogales, Arizona, under the auspices of the Nogales and Santa Cruz Port Authority,
4) a meeting in Hermosillo, Sonora, with regional stakeholders, as well as a meeting with ITESM
for a preview of the project's workscope and 5) a meeting in Nogales, Sonora, with the Fiscal
Corridor Working Group. Participants have included brokers and individuals from a number of
stakeholder entities, including the following:
Arizona Department of Transportation (ADOT), Special Border Projects Administrator
Arizona-Mexico Commission
Arizona State University
CANAMEX Corridor Coalition
City of Nogales, Sonora, Mexico
Fresh Produce Association of the Americas
Greater Nogales and Santa Cruz County Port Authority
Maquiladora Association of Sonora
Mexican Customs at Nogales (Aduanas Nogales)
Mexico's Department of Communications and Transport (Secretaría de Comunicaciones
y Transportes)
Nogales Community Development Corp., Nogales, Arizona
Nogales U.S. Customs Brokers Association
SouthEastern Arizona Governments Organization (SEAGO)
State of Sonora: Department of Infrastructure and Urban Development (Secretaría de
Infraestructura y Desarrollo Urbana), Roadway Board (Junta de Caminos del Gobierno
del Estado de Sonora); State of Sonora's Tourism Promotion Commission (Comisión de
Fomento al Turismo) and foreign commerce coordinator
The Sonora Arizona Commission (Comisión Sonora-Arizona)
Santa Cruz County
Transportes Pitic, S.A. de C.V.
U.S. federal agencies: Department of Homeland Security (DHS) and Customs and
Border Protection (CBP), Federal Highway Administration (FHWA), General Services
Administration (GSA)
1.5 Study Objectives
The study had three major objectives. The first objective was to collect traffic data that
could be analyzed the data to identify the location and nature of bottlenecks that impede the
efficient cross-border movements of people and goods into the Mariposa POE. The focus areas
for data collection include the roads immediately to the north and south of the Mariposa POE,
respectively SR 189 (Mariposa Rd.) and its major intersections, and the Fiscal Corridor. The
second objective was also to offer recommendations to alleviate congestion and provide
estimated costs. The final objective was to analyze the benefits of each recommendation based
on traffic analyses.
Bottleneck Study – Mariposa Port of Entry Page 44 of 212
2.1 Descriptions of Mariposa POE System
The study area for the Mariposa POE in the Nogales, Arizona, traffic network is defined
by the following boundaries:
• North: I-19 and Frank Reed Rd. intersection
• East: Grand Ave.
• West: Mariposa Rd.
• South: U.S.A. and Mexico border
The major roadways in the area are I-19 (known also as the Tucson-Nogales Highway),
Grand Ave., Country Club Drive, N. Old Tucson Rd., Valle Verde, Frank Reed Rd., Baffert
Drive, Mariposa Rd., White Park, Bankard, Doe, SR 82, Western Ave., Morley Ave., Walnut St.,
Crawford St., and Park St., with several points with significant intersections along Mariposa Rd.
The study area contains approximately twenty traffic signal controls, mostly concentrated along
Mariposa Rd. and Grand Ave. The area also houses numerous warehouses and container
facilities, as well as federal and state import and export inspection facilities. Refer to Figure 2-1
for a graphical representation of the Nogales, Arizona, study area.
Bottleneck Study – Mariposa Port of Entry Page 45 of 212
Figure 2-1 - Nogales, Arizona (U.S.), Traffic Network and Mariposa POE (Courtesy of ADOT)
The Nogales, Sonora, Mexico, study area is defined by the following boundaries:
• North: U.S. and Mexico border (POE)
• East: Plutarco Elias Calles Ave. and Prof. Alvaro Obregon Ave.
• West: Fiscal Corridor
• South: Fiscal Corridor and Prof. Alvaro Obregon Ave. intersection
It is important to note that the Southern end of the Fiscal Corridor accommodates a toll
and scale station that processes traffic proceeding Northbound on this Corridor. Refer to Figure
2-2 for a graphical representation of the study area.
Bottleneck Study – Mariposa Port of Entry Page 46 of 212
Figure 2-2 - Nogales, Sonora (Mexico), Traffic Network and Mariposa POE
2.2 Study Scope
The scope of the Mariposa POE Bottleneck study encompasses the following nine tasks.
The result of this task is a narrative report which is included in Sections 1.1, 1.2 and 1.3
of this report.
Bottleneck Study – Mariposa Port of Entry Page 47 of 212
Several stakeholders meetings were conducted to gain perspectives on Mariposa POE
bottlenecks and congestion. Information on the stakeholder meetings is provided in Section 1.4
and is reflected in the acknowledgements.
The description of the study area is provided in the last subsection. The research team
defined the north and south end points. In addition, the team described the major features of the
traffic network within the study area, including the number and direction of lanes and the
ingress/egress facilities to major highways as well as traffic signals and traffic management
The data appendices contain the products resulting from completing this task. In the
appendices are data on the travel demand, travel speed on main roads, the traffic volumes, delays
at main intersections and travel times collected manually around POE in the U.S. and Mexico
within the study area. Summaries of the data are given in Sections 4.1 and 4.2 of this report.
From the data collected, the research team determined border crossing times as well as
travel times, queues, and delays in order to ascertain the traffic capacities in the road network
and in the truck processing (document screening and inspection of trucks) capacities at the POE.
Results of this task are given in Section 5.1 of this report.
For the performance of this task, tables and maps were created showing road
infrastructure bottlenecks and traffic operation bottlenecks. The infrastructure examined
included factors such as the number of lanes, line dividers, traffic points of conflict, and
geometric design deficiencies. The traffic operations category included factors such as signaling
devices to direct traffic to designated lanes, traffic signals at intersections, and changeable
message signs providing crossers with updates. Results are included in Sections 6.1 and 6.2 of
this report.
The results associated with this task are reported in Section 6 on improvements
recommended on road infrastructure and traffic operations. The report includes cost estimates
for implementing the suggested improvements.
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The product associated with this task was the draft of this report that consolidated and
summarized the results from all previous tasks into one comprehensive document that was
submitted to ADOT for review.
The product for this task is this final report which is being submitted to ADOT, in PDF
format, and incorporates the comments provided through the ADOT review.
Bottleneck Study – Mariposa Port of Entry Page 49 of 212
3.1 Study Framework
The overall study framework, as shown in Figure 3-1, started with the collection of
background information, through both literature review and stakeholder meetings. As described
in the preceding sections, the stakeholder meetings generated useful information that allowed the
study team to identify the appropriate data collection season, dates, times, and locations. It was
decided that information on both volume and speed would need to be collected to provide a
comprehensive description of the congestion patterns and locations.
Using the collected field data, the study team analyzed the temporal and spatial traffic
patterns to identify any existing problems of congestion and bottlenecks. Through analysis of
possible mitigation strategies, the team would then recommend approaches to improve these
Figure 3-1 - Research Framework
3.2 Data Collection
The data collection team consisted of groups of students from the University of Arizona
and the Instituto Tecnológico de Estudios Superiores de Monterrey (ITESM) at Hermosillo. The
data collection dates were determined in consultation with the Technical Advisory Committee
(TAC) members and stakeholders. Data collection locations were determined along the major
Bottleneck Study – Mariposa Port of Entry Page 50 of 212
corridors, such as the intersections along Mariposa Rd., I-19, and Grand Ave. Data collection in
Mexico took place on the same dates, using locations at key points along Highway 15 and the
Fiscal Corridor.
In the Nogales, Arizona, area, both manual intersection counters and tube counters were
used at the selected locations. Intersection counters capture the vehicle turning volumes by
vehicle classes. Tube counters capture not only the traffic counts, but also the operating speeds.
In Nogales, Sonora, students were positioned at selected locations and manual vehicle counts
were collected by vehicle classes.
In addition, six camcorders were deployed; four at three locations in Nogales, Arizona,
and two in Nogales, Sonora. These camcorders were used to capture images of the commercial
vehicle license plates. The collected license plate data from each camcorder location was then
compared to the license plate data from other locations to find matches. The matches allowed
estimation of travel times on selected routes.
The study team coordinated with other ATLAS researchers working on another project
where data was being collected from an airborne platform. A helicopter carrying cameras
pointed vertically downward hovered over selected intersections in the study area on the same
dates, collecting videos and images of traffic during the same times that our team was collecting
ground-based data.
Further details relating to the data collection using the above-mentioned technologies will
be discussed in Chapter 4.
3.3 Bottleneck Identification
A bottleneck is defined as a location where significant delay is observed. This can be
caused by various roadway/traffic flow conditions – flow conflicts, roadway configurations, or
traffic controls. In this task, collected traffic data, in conjunction with observations on the
roadway configurations and traffic controls, were used to identify and quantify bottlenecks. The
license plate data were used to estimate the travel time over several segments along the study
corridor, including the Mariposa POE. Further information is given in Chapter 5.
3.4 Congestion Mitigation Strategies
Congestion mitigation strategies were postulated based on findings from the capacity
analysis and bottleneck identification tasks. These strategies can be categorized into (1) roadway
configuration improvements, (2) traffic control improvement, and (3) demand-supply integration.
Roadway configuration improvement strategies include changes of roadway geometry in order to
improve the traffic flow at various locations. Traffic control improvement strategies focus on
Bottleneck Study – Mariposa Port of Entry Page 51 of 212
adjusting the traffic signals to improve capacity and reduce delays due to traffic controls.
Demand-supply integration strategies investigate integrated treatments that create opportunities
for further improvement that goes beyond roadway configuration and signal control strategies.
This study also attempts to provide a general picture of how a re-designed Mariposa POE
may increase the inspection discharge flow rate and how this may create traffic congestion in the
study area. Such hypothetical scenarios consider several possible flow rate scenarios as per the
Mariposa POE Program Development Study Final Report, prepared for the General Service
Administration (2007). The estimated traffic through the Mariposa POE from the years 2003 to
2025, as shown in Table 3-1, increases from 238,340 to 338,468 commercial vehicles per year,
representing a 43% increase.
Table 3-1 Existing and Predicted Traffic Through Mariposa POE (Louis Berger Group and Performa, 2007)
Bottleneck Study – Mariposa Port of Entry Page 52 of 212
4.1 Planning for Data Collection
4.1.1 Nogales, Arizona, U.S.
Several preparatory steps were conducted prior to the actual data collection. ADOT lent
thirty safety vests to the research team to use during data collection. Four pneumatic tube
counters and eight hand-held intersection counters were rented for the Nogales, Arizona data
collection. Ten traffic counters were purchased for the Nogales, Sonora data collection. In
addition, six camcorders were purchased/borrowed in order to capture (via video) license plate
information on passing traffic.
Intersections and roads of interest for the data collection were identified in Arizona and
Sonora. For each location, a decision was then made on the types of data collection method to be
utilized, such as intersection or traffic tally counters, pneumatic tube counters or camcorder
recordings. Figure 4-1 shows data collection locations for intersection counters, pneumatic tube
counters, and camcorders on the traffic network for Nogales, Arizona.
For data processing purposes, each intersection counter, pneumatic tube counter and
camcorder was given an individual label based on location (L) and the two day data period (D),
such as AIntLD, ATbLD and AcamLD. For example, data collection on day 1 for intersection 5
in Nogales, Arizona, was labeled as AInt51. In this example, "A" indicates the Arizona side of
the border, "Int" is the intersection counter type of data collector, "5" is the location and "1" is
day one of data collection. Similarly, pneumatic tube counter 1 was labeled ATb51 and
camcorder 1 as ACam11 for day 1 data collection. Refer to Figure 4-1 for labels of the other
counter and camcorder locations in Nogales, Arizona.
Data collection 'crew' schedules for the fifteen-member Arizona team were drafted and
finalized for each of the locations prior to data collection. Data was collected on February 27th
and 28th for approximately ten continuous hours on each day.
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4 3 2
ACam2 & 3
Tube counter
Figure 4-1 - Nogales, Arizona, Data Collection Locations
4.1.2 Nogales, Sonora, Mexico
The planning process in Mexico started in the month of September 2007 when the
University of Arizona team visited ITESM Sonora Norte for a meeting with ITESM students.
The sixteen ITESM students who participated were selected based upon their academic
performance and interests. The faculty supervisor of the team was Industrial Engineering
Professor Gertie Agraz, who selected the team and coordinated its activities before, during and
after data collection.
In January 2008, the research team met with Gertie Agraz in Nogales and identified data
collection points in Nogales, Sonora. Subsequently, Dr. Elyse Golob of the University of
Arizona (UA) team and Gertie Agraz met with customs authorities in Sonora to let them know
that data collection would take place on February 27th and 28th..
The data collection points in Mexico were determined with the purpose of obtaining
necessary information on the flow of trucks from Mexico going north, regardless of their
Bottleneck Study – Mariposa Port of Entry Page 54 of 212
destination in U.S. or Canada. The data collection points in Nogales, Sonora, are shown in
Figure 4-2:
2 1
4 5
Traffic counter
Camcorders placed
100 m (328 ft) apart
Highway 15
(International Highway)
MCnt4 MCnt5
Figure 4-2 - Nogales, Sonora, Data Collection Locations
On February 26, Professor Chiu of the UA team conducted a training session for the
ITESM team at the Hotel Fiesta Inn in Nogales, Sonora. All the details on the data collection
process were explained to the ITESM team. Pairs of students were assigned to each data
collection point identified.
As seen in the previous figure, one data collection point (no. 1) is located at Highway 15
before the fork in the road, where one road leads to Nogales, Sonora, and the other to the
Mariposa POE. Three data collection points (nos. 2, 3 and 4) were located on the Fiscal
Two camcorders were located at point 4, just before the border, separated by 100 meters,
to record the license plates numbers of the trucks that were going north and about to cross the
border at the Mariposa POE.
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Points 5 through 8 were located inside the City of Nogales, Sonora, to collect data on
trucks and cars going through the city.
4.2 Traffic Data Collection
4.2.1 Nogales, Arizona, U.S.
Data collection in Nogales, Arizona, utilized eight hand held intersection counters, four
pneumatic tube counters, and four camcorders. It is important to note that camcorder directions
may change according to the specific day; further information is provided later in this section.
Figure 4-1 - Nogales, Arizona, Data Collection Locations depicts data collection locations for
intersection counters, pneumatic tube counters, and camcorders in the traffic network in Nogales,
Arizona. In the figure, a green circle identifies an intersection counter location, a red circle
identifies a camcorder location, and a blue line identifies a pneumatic tube.
During data collection, the team observed the following situations:
1. Most observed 18-wheelers were hauling a container; rarely were 18-wheelers seen
without a container.
2. There were greater volumes of 18-wheeler traffic on Wednesday, February 27th in
comparison to volumes on Thursday, February 28th.
3. Many 18-wheelers were observed entering/exiting area warehouse areas.
As indicated above, for data processing purposes, each intersection counter, pneumatic
tube counter and camcorder was given an individual label based on location (L) and the two day
data period (D). In addition to identifying locations for intersection counters, the research team
assigned a location and direction within the intersection where each student participant was to
face in order to collect data. For further clarification, Figure 4-3 through Figure 4-10 show aerial
and schematic views of the eight intersections where data was collected. The views illustrate the
specific location for each counter together with the direction in which traffic data was collected.
It is important to note that pneumatic tube counts and camcorder recordings were used
only for northbound traffic.
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Grand Ave
Figure 4-3 - Aerial View: Location and Direction for Intersection 1 Data Collection
W. Mariposa Rd E. Calle Sonora
N. Grand Ave.
Figure 4-4 - Aerial View: Location and Direction for Intersection 2 Data Collection
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Figure 4-5 - Aerial View: Location and Direction for Intersection 3 Data Collection
Figure 4-6 - Aerial View: Location and Direction for Intersection 4 Data Collection
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Figure 4-7 - Aerial View: Location and Direction for Intersection 5 Data Collection
Figure 4-8 - Aerial View: Location and Direction for Intersection 6 Data Collection
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Figure 4-9 - Aerial View: Location and Direction for Intersection 7 Data Collection
Figure 4-10 - Aerial View: Location and Direction for Intersection 8 Data Collection
Bottleneck Study – Mariposa Port of Entry Page 60 of 212
4.2.2 Nogales, Sonora, Mexico
The team had some initial difficulties in location of the data collection points, which had
been defined ealier on a map. At the actual site, the points along the Fiscal Corridor were hard to
establish due to safety concerns regarding students placement. The issues were resolved with
supervision from the tea
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