Final Tier 1 Environmental Impact Statement 4-1

4 Transportation Impacts

This chapter compares the potential transportation impacts associated with the 

implementation of passenger rail service within the corridor alternatives with the potential 

impacts of the No Build Alternative. Future ridership projections for passenger rail service are 

presented for each corridor alternative. In addition to passenger rail service characteristics, 

impacts to freight rail service, grade crossings, and vehicular traffic are discussed, including 

potential impacts during construction and long-term changes associated with highway/railroad 

grade crossings. 

Rather than include transportation impacts in Chapter 5, Existing Conditions and 

Environmental Consequences as one facet of the environment, these impacts have their own 

chapter in this Tier 1 EIS. The impacts speak directly to the purpose and need for the project; 

and, as a transportation project is being proposed to solve a transportation problem, the 

transportation impacts of the two corridor alternatives and of the No Build Alternative are of a 

magnitude that warrants their own chapter in the EIS.

ADOT has coordinated with all local agencies to obtain readily available long-range 

transportation plans within the study corridor illustrated in Figure 1-1. Major existing and 

planned transportation facilities for each transportation mode have been identified, including 

locations with substantial existing levels of congestion. A list of these plans and studies is 

included in the AA. 

A separate Service Development Plan (SDP) will be prepared as part of the APRCS following the 

approval of the Record of Decision (ROD). The SDP will provide more detail of the proposed 

passenger rail service.

4.1 Service Concept and Travel Forecasting

A primary objective of passenger rail is to deliver a service that can provide an effective 

alternative mode within the corridor. The success of the system depends on the travel time 

achievable and the reliability of the service compared to alternative travel modes. This section 

details the concept for service used for the Yellow and Orange corridor alternatives, assuming a 

regional higher speed (between 80 and 125 mph) train operation and building upon a blend of 

intercity and commuter considerations. These service assumptions (i.e., frequency of intercity 

or commuter trains, times of operation, schedule, stops, etc.) were developed to estimate 

ridership and capital and operating costs, as well as the effect of changes in vehicle miles 

traveled (VMT) on safety, noise, vibration, and air quality. The findings in this chapter are 

approximations based on a passenger rail system built on the alignments used in the AA. A 
4 Transportation Impacts

Final Tier 1 Environmental Impact Statement 4-2

future alignment elsewhere within the corridor alternatives may have different impacts and 

would be reevaluated in Tier 2 studies.

The FTA-developed Simplified Trips-on-Project Software (STOPS) model was used to provide an 

estimate of ridership for each of the corridor alternatives. The model replaces the standard 

“trip generation” and “trip distribution” steps with CTPP tabulations to predict detailed travel 

patterns, to quantify trips-on-project measure for all travelers and for transit-dependents, and 

to compute the change in automobile VMT based on the change in overall passenger rail 

ridership between the No Build and the corridor alternative scenarios. 

4.1.1 Yellow Corridor Alternative

For the purposes of this transportation impact analysis, the alignment of the Yellow Corridor 

Alternative would take advantage of an existing UP ROW. A passenger rail system operating at 

grade within the corridor would likely affect land uses and crossings along its entire length. At 

the same time, it could serve major population and activity centers and connect key trip origins 

and destinations directly. Potential station stops (shown in Table 4-1), frequencies, and overall 

travel times between terminal stations for the Yellow Corridor Alternative are summarized in 

this section. Documented assumptions include all three modeled Yellow Corridor Alternative 

service patterns, defined below and shown in Figure 4-1. It is possible for the commuter and 

intercity service patterns to overlap and run concurrently.

 Commuter (Grand Corridor ) – TUS to Surprise 

 Commuter (Yuma West Corridor) – TUS to Buckeye

 Intercity – Downtown Tucson to Downtown Phoenix

Table 4-1. Yellow Corridor Alternative Conceptual Stations

Station Name

Grand Corridor 

Pattern

Yuma Corridor 

Pattern

Intercity 

Pattern

Tucson International Airport X X

Tucson X X X

Orange Grove X X

Tangerine Road X X

Eloy X X X

Coolidge X X

San Tan Valley X X

Queen Creek X X

Cooley X X
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Final Tier 1 Environmental Impact Statement 4-3

Table 4-1. Yellow Corridor Alternative Conceptual Stations

Station Name

Grand Corridor 

Pattern

Yuma Corridor 

Pattern

Intercity 

Pattern

Downtown Gilbert X X

Downtown Mesa X X

Tempe X X

PHX X X X

Phoenix X X X

Glendale X

Peoria X

El Mirage X

Surprise X

Avondale X

Goodyear X

Buckeye X

Table 4-2 compares the assumptions for the combined frequencies (headways—the interval of 

time between trains on the same route—in minutes) of the three modeled Yellow Corridor 

Alternative service patterns. 

Table 4-2. Yellow Corridor Alternative Frequencies

Headways (minutes)

From 

Time

To Time

Grand Corridor 

Pattern

Yuma 

Corridor 

Pattern

Intercity 

Pattern

Combined Headway 

between DT Phoenix & DT 

Tucson

Southbound

5:30:00 9:29:00 30 60 60 15

9:30:00 14:59:00 180 180 --- 90

15:00:00 18:59:00 30 60 60 15

Northbound

5:30:00 9:29:00 30 60 60 15

9:30:00 14:59:00 180 180 --- 90

15:00:00 18:59:00 30 60 60 15
4 Transportation Impacts

Final Tier 1 Environmental Impact Statement 4-4

Figure 4-1. Yellow Corridor Alternative Operational Context
4 Transportation Impacts

Final Tier 1 Environmental Impact Statement 4-5

Total travel times based on detailed station-to-station travel times used in the AA are displayed 

in Table 4-3. 

Table 4-3. Yellow Corridor Alternative Travel Times (Tucson to Phoenix)

Station Name Commuter Operating Pattern Intercity Operating Pattern

Northbound 1:35:00 1:23:00

Southbound 1:36:00 1:22:00

4.1.2 Orange Corridor Alternative

For the purposes of this transportation impact analysis, the Orange Corridor Alternative would 

not make use of the existing rail corridor but would follow existing or proposed highways. 

Similar to the analysis in the AA, the Orange Corridor Alternative is assumed to be located on a 

separate alignment within highway corridors and may be grade separated in places (most likely 

elevated) to eliminate the need for numerous grade crossings and expedite travel within the 

metropolitan Phoenix area. This alternative would afford opportunities for higher speed rail 

travel but would include a substantial structural component in the project cost. The use of 

existing or proposed highway corridors would also impose certain constraints on the potential 

alignments, some of which do not serve population centers directly. In some cases, this could 

necessitate the use of a secondary transit service (e.g., bus or light rail) to access destinations. 

Potential station stops (shown in Table 4-4), frequencies, and overall travel times between 

terminal stations for the Orange Corridor Alternative are summarized in this section. 

Documented assumptions include all three modeled Orange Corridor Alternative service 

patterns as described below and shown in Figure 4-2. 

 Grand Corridor Pattern – TUS to Surprise

 Yuma West Corridor Pattern – TUS to Buckeye

 Intercity Pattern – Downtown Tucson to Downtown Phoenix 

Table 4-4. Orange Corridor Alternative Conceptual Stations

Station Name Grand Corridor 

Pattern

Yuma Corridor 

Pattern Intercity Pattern

TUS X X

Tucson X X X

Marana - Orange Grove X X

Marana - Tangerine X X

Eloy X X X
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Final Tier 1 Environmental Impact Statement 4-6

Table 4-4. Orange Corridor Alternative Conceptual Stations

Station Name Grand Corridor 

Pattern

Yuma Corridor 

Pattern Intercity Pattern

Coolidge-Florence X X

North Florence X X

Superstition Vistas X X

Mesa-Gateway Airport X X

Mesa-Power X X

Mesa-Country Club X X

Tempe X X

PHX X X X

Phoenix X X X

Glendale X

Peoria X

El Mirage X

Surprise X

Avondale X

Goodyear X

Buckeye X

Table 4-5 compares the assumptions for the combined frequencies (headways—the interval of 

time between trains on the same route—in minutes) of the three modeled Yellow Corridor 

Alternative service patterns. 

Table 4-5. Orange Corridor Alternative Frequencies

Headways (minutes)

From 

Time To Time Grand Corridor Pattern

Yuma 

Corridor 

Pattern

Intercity 

Pattern

Combined Headway 

between DT Phoenix & DT 

Tucson 

Southbound

5:30:00 9:29:00 30 60 60 15

9:30:00 14:59:00 180 180 --- 90

15:00:00 18:59:00 30 60 60 15

Northbound

5:30:00 9:29:00 30 60 60 15

9:30:00 14:59:00 180 180 --- 90

15:00:00 18:59:00 30 60 60 15
Final Tier 1 Environmental Impact Statement 4-7

Figure 4-2. Orange Corridor Alternative Operational Context
4 Transportation Impacts

Final Tier 1 Environmental Impact Statement 4-8

Total travel times based on detailed station-to-station travel times used in the AA are displayed 

in Table 4-6. 

Table 4-6. Orange Corridor Alternative Travel Times (Tucson to Phoenix)

Travel Direction Commuter Operating 

Pattern Intercity Operating Pattern

Northbound 1:44:00 1:30:00

Southbound 1:45:30 1:30:00

No passenger rail service currently operates within the Orange Corridor Alternative. UP 

operates approximately 10-15 freight trains per day on the Phoenix Subdivision line (between 

Eloy and downtown Phoenix) with speeds ranging between 15 miles per hour (mph) and 60 

mph. Conditions would not change with the No Build Alternative. 

4.1.3 Travel Demand/Benefits

Chapter 1, Purpose and Need of this Tier 1 EIS identifies the need to provide an effective 

alternative to automobile travel within the study corridor because conditions on the highway 

system are expected to deteriorate over time as population and travel in the corridor grow. The 

corridor alternatives were developed with that intent. The quantification of travel and safety 

benefits using anticipated changes in travel time, ridership, and VMT for each corridor alternative is 

the basis for the comparison of those measures in this chapter, as well as air quality and energy 

consumption (in Chapter 5, Existing Conditions and Environmental Consequences), compared with 

anticipated conditions under the No Build Alternative. 

Corridor Alternatives

Travel Time

The SDP will be completed and adopted by ADOT following the publication of the Final EIS and 

issuance of a FRA Record of Decision. Given the assumed level of rail service outlined in the 

SDP as it is being developed, the corresponding personal vehicle travel time between the two 

urbanized areas is detailed in Table 4-7. No Build Alternative travel times are based on the 

Arizona Statewide Travel Demand Model version 2 (AZTDM2). 
4 Transportation Impacts

Final Tier 1 Environmental Impact Statement 4-9

Table 4-7. Estimated Rail and Auto Travel Times between Tucson and Phoenix

Yellow Corridor Rail 

Alternative (Hrs:Min)

Orange Corridor Rail 

Alternative (Hrs:Min)

No Build Alternative

(Auto Travel) 

(Hrs:Min)

2010 1:53

2035 1:23 (Intercity) 1:30 (Intercity) 2:22

2050 1:23 (Intercity) 1:30 (Intercity) 2:59

Ridership

Ridership forecasts are a measure of the potential success of the proposed service based on the 

demand for its use. Ridership was estimated using an FTA forecasting model called STOPS. It 

was designed specifically to estimate ridership on fixed guideway systems. While its original 

purpose was for travel in urban environments on New Starts and Small Starts (FTA grant 

programs for funding major infrastructure investments) projects, it generates reasonably highlevel forecasts for the Tier 1 EIS analysis of the Tucson to Phoenix corridor.

The development of STOPS evolved directly from the requirement established in FTA’s Final 

Rule on major capital investments: to provide a simplified method that project sponsors can 

use, at their option, to quantify the trips-on-project measure and the VMT change needed for 

the environmental effects analysis. 

Because the proposed service is a blended concept that includes intercity and commuter trips, 

the STOPS application was set up to identify trips of less than 40 miles and trips of more than 

40 miles. The longer trips are an estimate of the expected intercity travel demand.

The output from STOPS shows both unlinked and linked transit trips in the modeled area. The 

“unlinked” trips are all the component segments of a transit trip identified separately (i.e., a 

transfer from one bus route to another represents two unlinked trips), while “linked” trips 

count the entire trip from beginning to end as a single trip (i.e., the same two unlinked trips in 

the transfer above represent a single linked trip). This information is shown quantitatively in 

Table 4-8.
4 Transportation Impacts

Final Tier 1 Environmental Impact Statement 4-10

Table 4-8. Year 2035 Tucson-Phoenix Commuter and Intercity Trip Demand

Yellow Corridor 

Alternative

Orange Corridor 

Alternative

No Build 

Alternative

Unlinked transit trips 476,000 475,000 451,000

Linked transit trips 343,000 343,000 324,000

Total Daily Rail Ridership 20,060 18,080 N/A

Intercity trips (>40 miles) 3,360 4,140 N/A

Commute trips (<40 miles) 16,700 13,940 N/A

Total by Service Type 20,060 18,080

Daily VMT reduction 566,914 570,268 N/A

Daily VHT reduction 17,522 17,655 N/A

Notes: VHT = Vehicle Hours Traveled

Safety

Overall passenger safety in the corridor would improve because passenger rail service would 

divert some automobile trips to an alternate mode of travel. The safety risk to travelers would 

decrease, as rail travel is statistically safer per passenger mile than automobile travel. The 

overall potential decrease in automobile traffic that could be realized with implementation of 

passenger rail service would be expected to reduce potential automobile injuries and fatalities 

within the corridor. The potential annual reduction in fatalities and injuries within the Yellow 

and Orange corridor alternatives is estimated as part of FTA STOPS model forecasts and shown 

in Table 4-9. 

Table 4-9. Safety Improvement (per 1,000,000 VMT in 2035)

Yellow Corridor 

Alternative

Orange Corridor 

Alternative

No Build 

Alternativea

Annual fatality reduction 2.2 2.2 N/A

Annual injury reduction 33.2 33.4 N/A

Note: Assumes trains run 300 days a year. 

a Potential increases in fatalities and injuries under the No Build Alternative were not estimated for this Tier 1 

analysis.

With additional trains operating within either corridor alternative, the possibility of train 

collisions is increased as a result of increased activity between freight and passenger services 

and a higher number of trains at grade crossings; however, the signaling system, such as 

positive train control as required by the Rail Safety Improvement Act of 2008 (RSIA), would be 

designed to mitigate this risk.
4 Transportation Impacts

Final Tier 1 Environmental Impact Statement 4-11

No Build Alternative

Current travel time between Tucson and Phoenix is approximately 113 minutes and is projected 

to increase to 179 minutes by 2050, even with the addition of substantial new roadway capacity 

along I-10 and on the proposed North-South Corridor, based on AZTDM2. No passenger rail 

service currently exists in the Tucson-to-Phoenix corridor. 

4.2 Operational Impacts to Freight Rail Service

4.2.1 Corridor Alternatives

Yellow Corridor Alternative 

ADOT has had ongoing discussions with UP, the freight operator in the corridor, related to the 

proposed Yellow Alternative. Based on the information obtained from UP and analysis of the 

alternative, the implementation of passenger rail within the Yellow Corridor Alternative is not 

expected to result in a change in the number of freight trains currently operating in the Tucson 

to Phoenix corridor, although some freight train scheduling modifications may be required to 

prevent conflicts with passenger service. Upgrades to the existing UP track were assumed as 

part of this alternative in addition to projects to accommodate passenger rail operations. These 

potential improvements include: 

 New at-grade single track

 New at-grade siding tracks

 New siding turnouts, where needed

 New roadway-rail grade crossings 

 Reconfiguration of UP track where needed

 Centralized train control signal systems

 Positive train control systems where required by FRA regulations.

These projects would allow continued service to freight customers and mitigate potential 

restrictions to freight movements.

Orange Corridor Alternative

The implementation of passenger rail within the Orange Corridor Alternative would have 

minimal impact to existing freight rail service. Impacts would be restricted to the portion of the 

corridor between Tempe and downtown Phoenix/West Valley and downtown Tucson to TUS. 

Within the portion of the passenger rail corridor which is shared with the freight rail corridor, 

the following typical projects would be implemented:
4 Transportation Impacts

Final Tier 1 Environmental Impact Statement 4-12

 Rehabilitation of single track where necessary

 New at-grade single track

 New at-grade siding tracks

 Centralized train control signal systems

 Positive train control systems where freight and passenger train activity intersect

During operation of the passenger rail system, freight rail service could be maintained with 

minimal scheduling modifications and limited need for coordination with the passenger rail 

service.

4.2.2 No Build Alternative

The No Build Alternative consists of current freight rail conditions with no additional track 

upgrades, capacity increases, or signal projects planned.

4.3 Grade Crossing Impacts

4.3.1 Corridor Alternatives

Yellow Corridor Alternative 

Under the Yellow Corridor Alternative, modifications or improvements would be made to all 

grade crossing signals. Additionally, it is possible that some grade crossings would be converted 

to grade-separated crossings. All grade crossings would be upgraded to four-quadrant gates. 

For locations already equipped with four-quadrant gates, construction to accommodate the 

upgraded service could be required, such as in areas with additional track. Grade-separated 

crossings can be considered as part of implementing the Yellow Corridor Alternative and 

require further analysis. Some locations can be determined using safety records maintained by 

ADOT, but the identification of the exact locations would require further analysis. Vehicular 

delay at the grade crossings would increase due to the addition of the more frequent passenger 

rail operations and advanced warning times. This delay would be eliminated at grade 

separations. 

Orange Corridor Alternative

Under the Orange Corridor Alternative, modifications or improvements would be made to all 

grade crossing signals, which are limited to the areas between Marana and TUS, and between 

downtown Tempe and downtown Phoenix. Additionally, 15 new grade-separated crossings 

would be assumed to be installed in the area between Marana and Phoenix-Mesa Gateway 

Airport as part of the North-South Corridor development and the use of the Superstition Vistas 
4 Transportation Impacts

Final Tier 1 Environmental Impact Statement 4-13

transit corridor. All grade crossings would be upgraded to four-quadrant gates. For locations 

already equipped with four-quadrant gates, construction to accommodate the upgraded service 

may be required, such as in areas with additional track. Vehicular delay at existing grade 

crossings would increase due to the addition of passenger rail service operations and advanced 

warning times.

4.3.2 No Build Alternative

Under the No Build Alternative, no passenger rail system would be constructed, and no changes 

to existing roadway-rail grade crossings would be anticipated. No projects are currently planned 

to upgrade existing grade crossings beyond regular maintenance. The No Build Alternative 

would have no effect on UP operations.

4.4 Rail Service Impacts during Construction

4.4.1 Corridor Alternatives

In the case of the Yellow Corridor Alternative, ADOT would obtain permission and participation 

from UP for all construction that would take place within the railroad ROW, including 

coordination to ensure continued access and maintenance of customer service. In the case of 

the Orange Corridor Alternative, the corridor has little interaction with the railroad, although 

permission would be sought for any coordination needs in the short distance between Tempe 

and Phoenix and in downtown Tucson. In general, corridor construction would affect rail traffic 

by reducing operating train speeds through construction zones and adding to rail travel time. 

This may occur when adding new siding tracks, double-tracking, upgrading signals, and 

modifying grade crossings. The other impact would be schedule adjustments for existing 

operations to create windows of opportunity for temporary suspension of rail operations on 

selected track sections, such as when new turnouts are being placed for passing sections and 

new sidings or if a potential safety risk may occur. During construction, temporary “shoo-fly” 

trackage may need to be installed for longer disruptions; or brief track outages, which would 

interrupt freight service temporarily, may be necessary. Minimal construction impacts are 

associated with the Orange Corridor Alternative as compared to the Yellow Corridor 

Alternative. 

4.4.2 No Build Alternative

Under the No Build Alternative, construction would be limited to regular maintenance 

activities; therefore, no impacts to rail service would occur.
4 Transportation Impacts

Final Tier 1 Environmental Impact Statement 4-14

4.5 Vehicular Traffic Impacts during Construction

4.5.1 Corridor Alternatives

Vehicular traffic would be temporarily affected at locations where grade crossings would be 

separated or modified. While the exact construction zones have not been determined at this 

time, temporary lane closures or roadway closures would likely be required to construct a 

passenger rail system. Grade crossing construction would, at a minimum, slow traffic down as it 

passes through the construction zone. In some cases, temporary diversion of traffic to adjacent 

crossings could be required. 

Construction of grade-separated crossings would be staged to minimize street closures. This 

may be accomplished by closing the outside lanes during retaining wall and bridge abutment 

construction while maintaining traffic on the inside lane. The adjacent parallel streets would be 

used for detour traffic during street closures. Another option is to construct a temporary detour 

around the construction site, which would reduce the amount of out-of-direction travel to 

parallel routes.

Where impacts to vehicular traffic occur, emergency services, schools, businesses, and other 

activities requiring vehicular access would be affected by potential delays or detours. 

Construction-related impacts to vehicular traffic would be temporary, however; and ADOT 

would undertake a public outreach program prior to construction to notify schools, emergency 

service providers, residents, and businesses. 

4.5.2 No Build Alternative

No construction activity associated with a passenger rail system would occur in the No Build 

Alternative.

4.6 Station Location and Local Parking Impacts

4.6.1 Corridor Alternatives

Concept plans have not been developed for station locations, as specific locations have not yet 

been determined. Station area concept plans would be developed as the projected ridership 

forecasts are refined, to allow the determination of required station size, number of parking 

spaces, transit amenities, and vehicular circulation. It is assumed that the location of new 

stations would be easily accessible from the highway and arterial system and would also 

accommodate transit, bicycle, and pedestrian access. Generalized station type concepts (i.e., 

hub, regional, local, emerging) have been developed as a model for future stations pending the 

requisite information about demand for services and physical location. These are presented in 
4 Transportation Impacts

Final Tier 1 Environmental Impact Statement 4-15

the Station Area Planning Guidance for Communities at the end of the Alternatives Analysis 

Appendix. 

Constructing and operating passenger rail stations have the potential to generate impacts that 

require mitigation. These could be related to:

 property acquisition and displacements,

 changes in land use and economic development potential,

 the need to relocate and/or reconstruct displaced community facilities,

 congestion resulting from intensified travel activity at stations, including parking, 

facilities, that could require reconfiguration of existing streets or diversion of vehicular 

traffic, and 

 the need to facilitate station access by alternative modes while ensuring pedestrian and 

bicycle safety as a result of increased congestion.

Any such impacts would be addressed during Tier 2 analysis.

4.6.2 No Build Alternative

No station construction or effects on local parking would take place under the No Build 

Alternative.

4.7 Corridor Cross Sections

The transportation impact analysis of the Yellow and Orange Corridor Alternatives did not 

consider detailed design concepts of a passenger rail track alignment. However, in order to 

better understand the potential impact of an alignment’s built condition within a corridor, 

typical rail cross sections were developed. These cross sections are not meant to distinguish 

between the Yellow and Orange Alternatives, and are intended only as a means to gauge 

potential ROW impacts of different possible scenarios. More detailed analysis in the future may 

bring to light factors or conditions which change these assumptions. Figure 4-3, Figure 4-4, and 

Figure 4-5 show the typical cross sections for single track, double track, and double track with a 

station platform, respectively. While these cross sections are only an illustration of possible 

configurations, any elements such as station platforms or other features would be designed and 

constructed to conform to the requirements of the Americans with Disabilities Act (ADA).
4 Transportation Impacts

Final Tier 1 Environmental Impact Statement 4-16

Figure 4-3. Cross Section – Single Track
4 Transportation Impacts

Final Tier 1 Environmental Impact Statement 4-17

Figure 4-4. Cross Section – Double Track

Figure 4-5. Cross Section – Station Platform