1
chapter
1
Purpose and Need
PURPOSE OF THE DOCUMENT
The Arizona Department of Transportation (ADOT),
the project sponsor, working in close consultation with
the Federal Highway Administration (FHWA), the
lead federal agency for the proposed action, and in
cooperation with the U.S. Army Corps of Engineers
(USACE), the U.S. Bureau of Indian Affairs (BIA), and
the Western Area Power Administration (Western), has
prepared this Draft Environmental Impact Statement
(DEIS) and Section 4(f) Evaluation in accordance with:
➤➤ the
National Environmental Policy Act (NEPA)
of 1969 [42 United States Code (U.S.C.) § 4332(2)(c)]
➤➤ Section 4(f) of the U.S. Department of
Transportation Act of 1966 (49 U.S.C. § 303,
as amended)
➤➤ Section 404 of the Clean Water Act of 1977
(33 U.S.C. § 1251)
The DEIS and Section 4(f) Evaluation 1) satisfies FHWA
and ADOT’s environmental analysis requirements;
2) provides a comparison of the social, economic,
and environmental impacts that may result from
implementation of the proposed action—construction and
operation of a major transportation facility; and 3) identifies
measures to avoid, reduce, or otherwise mitigate adverse
impacts. The DEIS includes sufficient preliminary design
information to compare alternatives.
The Safe, Accountable, Flexible, Efficient Transportation
Equity Act: A Legacy for Users (SAFETEA-LU) was
passed into law on August 10, 2005. This legislation
addresses improving transportation safety, reducing
traffic congestion, improving freight movement efficiency,
increasing intermodal connectivity, and protecting the
environment. Moving Ahead for Progress in the 21st
Century (MAP-21) was passed into law on July 6, 2012.
This legislation creates a streamlined performance-based
surface transportation program. The South Mountain
Freeway Environmental Impact Statement (EIS) was
initiated prior to the passage of SAFETEA-LU and
MAP-21 and is not subject to their procedural directives.
Certain aspects of the legislations have, however, been
incorporated within this document.
PURPOSE OF THE CHAPTER
A major transportation facility (the South Mountain
Freeway) has been included in past and current regional
transportation planning efforts. At the beginning of the
EIS process, the need for a major transportation facility
was reexamined to determine whether such a facility is
still needed.
Sections of the chapter are presented to provide the
reader an overall understanding of the analyses used to
determine the purpose and need for the proposed action.
Table 1-1 on the following page provides a summary of
topics, content, and intended benefit to the reader.
CONTEXT OF PURPOSE AND NEED
IN THE EIS PROCESS
An early step in preparing an EIS is to determine whether
there is a purpose and need for the proposed action
(see sidebar on this page regarding purpose and need content
guidance). If the lead agency concludes through analysis
that there is no need, an EIS would not be prepared. If
the lead agency concludes through analysis that there is a
need, the EIS process would continue with evaluation of a
range of reasonable alternatives for a transportation facility
in the Study Area. The Study Area for this proposed
action has been defined as the southwestern portion of the
Phoenix metropolitan area (see Figure 1-1).
The analysis used to determine the possible purpose and
need for the proposed action followed FHWA guidance.
The following may assist in explaining some items to
be considered in establishing the purpose and need for a
proposed action. They are not intended to be all-inclusive;
they are intended as guides.
➤➤ Capacity –
Is the capacity of present facilities
adequate for the present and/or projected traffic?
What capacity is needed? What are the existing and
proposed facilities’ current and/or projected level(s)
of service (LOS) (see text box on page 1-14)?
➤➤ Transportation demand – Is
the proposed action
related to any statewide plan or adopted urban
transportation plan? Are the proposed action’s traffic
forecasts substantially different from those estimates
from the region’s transportation planning process?
➤➤ Social demands or economic development –
What
projected socioeconomic, demographic, and/or land
use changes indicate the need to improve or add to the
transportation system capacity?
A proposed action’s purpose and
need documentation should:
“Identify and describe the proposed action
and the transportation problem(s) or other
needs which it is intended to address
(40 Code of Federal Regulations
[C.F.R.] § 1502.13). This section should
clearly demonstrate that a ‘need’ exists
and should define the ‘need’ in terms
understandable to the general public.
This discussion should clearly describe
the problems which the proposed action
is to correct. It will form the basis for the
‘no action’ discussion in the ‘Alternatives’
section, and assist with the identification
of reasonable alternatives and the selection
of the preferred alternative. Charts,
tables, maps, and other illustrations
(e.g., typical cross-section, photographs,
etc.) are encouraged as useful presentation
techniques.”
Source: FHWA Technical Advisory
T 6640.8A, Guidance for Preparing and
Processing Environmental and Section 4(f)
Documents (U.S. Department of
Transportation, T‑FHWA, 1987)
Attention readers!
Acronyms, abbreviations, a glossary, a list
of preparers, references, and an index can
be found in the back of the DEIS.
South Mountain Freeway (Loop 202) DEIS and Section 4(f) Evaluation
1-1
1-2
Chapter 1
Table 1-1
1
•
Purpose and Need
South Mountain Freeway (Loop 202) DEIS and Section 4(f) Evaluation
Purpose and Need Content Summary, Chapter 1
Topic
Page
Highlights
Reader Benefit
●
●
Context of Purpose and Need
in the EIS Process
1-1
●
Context of purpose and need in the EISa
process
Context of the proposed action relative to the
ADOTb mission
●
●
●
●
Project Location, Description,
and Current Status
1-4
●
●
●
●
●
Historical Context of the
Proposed Action
1-5
●
●
Context of the Proposed
Action in Current Regional
Transportation Planning
Overview of proposed action location and
description
Establishment of the proposed action as a
distinct action
Definition of the RTPc
Factors contributing to growth of the region
Historical population, employment, and
housing growth rates
Evolution of the region’s transportation
network and its relationship to the proposed
action
Transportation planning in conjunction with
the region’s growth
Voter support relative to transportation
planning efforts
●
●
●
●
●
●
●
1-9
●
The proposed action as part of the RTP
●
●
Need Based on Socioeconomic
Factors
1-11
●
Projected population, housing, employment,
and vehicle miles traveled
Relationship of the proposed action to
projected growth
●
●
●
Need Based on Regional
Transportation Demand
and Existing and Projected
Transportation System Capacity
Deficiencies
●
1-13
●
Existing traffic conditions in the Study Area
and immediate surroundings
2035 forecast traffic conditions in the Study
Area and immediate surroundings
●
●
●
Conclusions
a
environmental impact statement
1-21
b
●
Determination of need for a major
transportation facility
Arizona Department of Transportation
c
Regional Transportation Plan
●
d
An understanding of the issues and factors considered in assessing the proposed
action’s purpose and need
General guidance on how to assess the purpose and need for a proposed action
An understanding of the documentation of the proposed action’s purpose and need
as a step in the EIS process
An understanding of ADOT’s obligation to Arizona citizens in relation to meeting
transportation needs
Orientation of the reader to the Study Area
Information the reader can use regarding a major transportation facility in the
context of the region’s current transportation planning
An understanding of the region’s historical growth patterns and factors contributing
to that growth
Identification of the stakeholders responsible for regional planning efforts
An understanding of how the idea for the proposed action originated and how it
evolved over time
The role of the public in regional transportation planning efforts in recent history
through voter approval and regional transportation plan development
An understanding of the proposed action as one of many interdependent components
that make up the planned transportation network in the MAGd region
An understanding of the proposed action as a key piece of the RTP since the mid-1980s
An understanding of the region’s projected growth patterns and factors contributing
to the growth
An understanding of why a major transportation facility is needed in this area of the
MAG region
An understanding of 2010 and 2035 traffic volumes on freeways and arterial streets in
the region and Study Area
An understanding of 2010 and 2035 operational characteristics of the region’s
transportation network
An understanding of 2010 and 2035 travel times at representative locations in the
region
An understanding of projected deficiencies in the planned transportation network
Summary of the conclusions reached regarding the need for a major transportation
facility in the Study Area
Maricopa Association of Governments
South Mountain Freeway (Loop 202) DEIS and Section 4(f) Evaluation
Chapter 1
the global economy, promotes economic prosperity, and
demonstrates respect for Arizona’s environment and
quality of life. Its stated goals relating to the proposed
action are to:
The chapter analyzes these questions to determine
whether purpose and need for the proposed action exist.
A conclusion section, presented at the end of the chapter,
summarizes findings regarding the proposed action’s
purpose and need.
public and political support necessary to meet
Arizona’s transportation needs
ADOT’s mission is to provide a safe, efficient, costeffective transportation system that links Arizona to
➤➤ optimize
1
ADOT’s mission and stated goals are important in
the context of determining the purpose and need for
the proposed action. As the project sponsor, ADOT
is obligated to continue to study the proposed action
if analysis concludes there is purpose and need for the
action.
the movement of people and products
throughout Arizona
➤➤ increase
1-3
Purpose and Need
➤➤ enlist
➤➤ improve
Context of the Proposed Action Relative
to the ADOT Mission
•
the quality, timeliness, and costeffectiveness of ADOT’s products and services
resource use
Figure 1-1 Study Area
60
Metro
Phoenix
51
35th Avenue
to Flagstaff
Phoenix Sky Harbor
International Airport
60 Superstition
Freeway
Dobbins Road
Elliot Road
Phoenix South
Mountain Park/Preserve
Estrella Drive
LOOP
101
Gi
LOOP
Desert Foothills Parkway
LOOP
202
The Study Area for the proposed action encompasses the southwestern portion of the Phoenix metropolitan area.
PINAL COUNTY
n
MARICOPA COUNTY
Not to scale
Gila River Indian Community
within Study Area
Santan
Freeway
cso
Tu
PIMA
COUNTY
Study Area
Existing freeway
Gila River Indian Community
boundary
Maricopa County line
to
Note: For a history of alternatives
development on Gila River Indian
Community land, see Chapter 2,
Gila River Indian Community Coordination.
PINAL
COUNTY
Location of Study Area
Sierra Estrella
17th Avenue
79
Pecos Road
27th Avenue
Casa Grande
8
r
Florence
Gila River
Indian Community
ve
Ri
85
Price
Freeway
Chandler Boulevard
la
202
Gila Bend
10 Freeway
Ray Road
60
10
LOOP
101
Maricopa
10
STUDY AREA
Hohokam
Freeway
Baseline Road
87
17
43rd Avenue
Southern Avenue
Payson
GILA
COUNTY
MARICOPA
COUNTY
51st Avenue
59th Avenue
67th Avenue
75th Avenue
99th Avenue
107th Avenue
Broadway Road
alt River
S
YAVAPAI
COUNTY
143
Lower Buckeye Road
48th Street
Location in state
Buckeye Road
Dobson Road
Not
to scale
Red Mountain
Freeway
Downtown
Phoenix
40th Street
Tucson
Mexico
Van Buren Street
Price Road
10
LOOP
202
Papago
McClintock Road
STUDY AREA
8
Black Canyon
Rural Road
MARICOPA
COUNTY Phoenix
Pima
Freeway
10 Freeway
El Mirage Road
10
to Los Angeles
101
17 Freeway
32nd Street
17
LOOP
Piestewa
Freeway
Kyrene Road
New
Mexico
51
24th Street
California
Flagstaff
Avondale Boulevard
40
115th Avenue
Nevada
Agua Fria
Freeway
83rd Avenue
LOOP
101
91st Avenue
Colorado
Utah
Approximate scale
1
5 miles
1-4
1
What are logical termini
and independent utility?
Logical termini refer to rational end points
for a transportation project and for a review
of environmental impacts. Often, termini
are points of major traffic generation, such
as intersecting roads or major population
centers, but other rationales can support
determination of logical termini for a
project. Such considerations include
establishing a corridor of sufficient length
to compare a range of alternatives and
ensuring the project will not restrict
consideration of alternatives for other
reasonably foreseeable transportation
improvements.
Independent utility means the ability of the
proposed action to function independently
of other planned transportation-related
projects in the region.
The proposed facility must be usable and
be a reasonable expenditure even if no
additional transportation improvements
are made within the area.
How are MAG data used in the
DEIS?
As a key stakeholder and data source for
the project, MAG has provided critical
resources for compiling background
information and developing data for the
DEIS analyses. To identify the use of
MAG resources, three forms of citation are
used throughout this document:
• This citation is used when information was
extracted directly from a MAG-developed
document.
Source: Maricopa Association of
Governments, year
• This citation is used when data are
presented as received from MAG.
Source: Maricopa Association of
Governments, year; used with permission
• This citation is used when analysis was
performed using MAG data as inputs.
Source: Maricopa Association of
Governments, year; extrapolated analysis
Chapter 1
•
Purpose and Need
PROJECT LOCATION, DESCRIPTION,
AND CURRENT STATUS
Location and Description
The geographic area for which a major transportation
facility has been identified in the past is in the
southwestern portion of Maricopa County, Arizona
(see Figure 1-1). The general area includes the southern
and western city limits of Phoenix, Arizona. The logical
termini (see sidebar on this page) for a project in the area
are:
➤➤ In
the west, Interstate 10 (I-10, Papago Freeway)
is a major east–west Interstate highway and a
major transportation corridor serving regional and
interstate travel. The project would terminate at
I-10 between 115th Avenue/Avondale Boulevard
(milepost 131.7) and 43rd Avenue (milepost 140.7).
➤➤ In
the east, State Route (SR) 202L (Santan
Freeway) and I-10 (Maricopa Freeway) are major
transportation corridors serving regional and
interstate travel. The project would terminate near
the system traffic interchange (see discussion of
traffic interchanges, on page 3-48) connecting those
freeways at milepost 161.3 on I-10.
South Mountain Freeway (Loop 202) DEIS and Section 4(f) Evaluation
What Is the Maricopa Association of Governments?
MAG was created in 1967 to foster regional cooperation
and address regional challenges in the greater Phoenix
metropolitan area. In 1973, MAG became the designated
metropolitan planning organization for regional planning
in the Maricopa County region. Its current membership
includes Maricopa County and the 25 incorporated towns
and cities and 3 Native American Indian communities within
Maricopa County and the contiguous urbanized area. ADOT
and the Citizens Transportation Oversight Committee serve
as ex-officio members for transportation-related issues.
MAG is at the service of its members (the local
governments and citizens in the region); the association
does not make decisions on behalf of its members without
member majority approval. By fostering communication,
planning, policymaking, coordination, advocacy, and
technical assistance, MAG serves to facilitate and create an
environment for its members to address issues and needs
that cross city, town, county, and even state boundaries.
YAVAPAI COUNTY
Carefree
Wickenburg
Cave
Creek
Peoria
MARICOPA
COUNTY
Scottsdale
Fountain
Hills
Phoenix
Surprise
Current Status of the Proposed Action
A major transportation facility (the South Mountain
Freeway) has been included in the Maricopa Association
of Governments’ (MAG, see text box on this page)
adopted transportation planning documents since 1985
and is in the current MAG Regional Transportation Plan
(RTP, see text box on next page). Since 1985, the South
Mountain Freeway has also been part of long-range
planning efforts of local jurisdictions (e.g., the City of
Phoenix) throughout the Study Area. Adopted in 2003
and last updated in 2010, the RTP is a comprehensive
regional multimodal plan that addresses needs for all
transportation modes and for planned transportation
improvements in the MAG region beginning in 2006
and ending in 2026. Figure 1-2 illustrates the freeway
network as proposed in 1985 and as presented in the
The Articles of Incorporation for MAG state that the
association was formed to:
• provide a forum for discussion and study of regional
problems of mutual interest to the governments in the region
• ensure, through cooperation and the pooling of
common resources, maximum efficiency and economy
in governmental operations that will provide every
citizen with the utmost value for every dollar expended
• identify and comprehensively plan for the solution of
regional problems (including transportation) requiring
multicity, town, and county cooperation
• facilitate agreements among the governmental units for
specific projects or other interrelated developmental
actions or for the adoption of common policies with
respect to problems common to its members
• attain the greatest degree of intergovernmental
cooperation possible to prepare for future growth and
development of the region
El Mirage
Youngtown
Litchfield Park
Buckeye
Paradise
Valley
Glendale
Tolleson
Guadalupe
Tempe
Fort McDowell
Yavapai Nation
Salt River-Pima
Maricopa Indian
Community
Mesa
Apache
Junction
Gilbert
Chandler
Queen
Creek
Goodyear
Avondale
Gila River
Indian Community
PINAL COUNTY
Gila Bend
MARICOPA COUNTY
Unidentified areas in light green are
unincorporated Maricopa County
Not to scale
MAG members’
municipal planning areas
Jurisdictional boundaries
Maricopa County line
Study Area
Note: MAG serves member agencies whose jurisdictions include those in Maricopa County and some whose jurisdictions
extend into portions of Pinal and Yavapai counties.
Source: Maricopa Association of Governments, 2006a
South Mountain Freeway (Loop 202) DEIS and Section 4(f) Evaluation
Chapter 1
recognizes different transportation needs in different
areas of the MAG region. The planning process for the
RTP, among other things, included:
· evaluation of the region’s population, economic, and
planned land use development trends
• analysis of the condition of the transportation system
• assessment of transportation needs for its 20‑year
planning horizon
• identification of transportation investments to best
meet future regional needs
MAG members consider the RTP to be vital in addressing
transportation needs in response to and in support of
continued growth and economic sustainability in the MAG
region. The Regional Freeway and Highway System, an
integrated system of beltway and arterial freeways, is a
principal component of the RTP.
As the “blueprint for future transportation investments
in the region for the next several decades” (MAG 2003),
the RTP is a performance-based, integrated plan that
· new lanes
· improved intersections and
“smart” signals
· reduced bottlenecks
· improved continuity
· new and expanded commuter
express service
· light rail extensions
· additional local bus routes
Black Canyon
17 Freeway
Streets
Transit
51
303
LOOP
101
Piestewa
Freeway
LOOP
Agua Fria
Freeway
101
Pima
Freeway
LOOP
202
Red Mountain
Freeway
Papago
10 Freeway
Maricopa
10 Freeway
30
To be named
· new freeways
· new general purpose and
high-occupancy vehicle lanes
· improved interchanges
LOOP
South Mountain
Freeway
➤➤ The
Grand Avenue portion of U.S. Route 60
(US 60) is maintained as a major arterial street,
providing access to most intersecting streets and
some access to adjacent properties.
➤➤ The
1985-proposed Paradise Parkway is no longer
included in the RTP.
➤➤ Most
➤➤ The
of SR 202L is completed and operating.
general location for the South Mountain
Freeway has remained unchanged since 1985.
The decision to study the proposed action in this
document is based on logical termini, sufficient
length, independent utility, projected travel needs,
and construction priorities. This document recounts
the analysis used to determine whether the proposed
action could meet regional transportation needs
in an environmentally acceptable manner and at a
reasonable cost.
HISTORICAL CONTEXT
OF THE PROPOSED ACTION
Over the course of its Euro-American history, the
Phoenix metropolitan area has experienced continuous
growth. Several factors have substantially contributed
to the area being a popular destination for people and
industry, and several of these factors are expected to
contribute to the area’s future growth. It is important to
understand:
these factors have driven growth and will
continue to drive growth
Other RTP elements
202
1-5
➤➤ how
Hohokam
Freeway
60 Superstition
Freeway
Freeways
Not to scale
143
Purpose and Need
current RTP. Some notable observations pertaining to
Figure 1-2 are:
What Is the Regional Transportation Plan?
The result of a major planning effort initiated in 2001 and
completed in late 2003, the RTP provides a broad, integrated
vision for the regional transportation system through 2026,
addressing freeways, streets, transit, airports, bicycle and
pedestrian facilities, freight, demand management, system
management including intelligent transportation systems,
and safety. The plan received unanimous support from the
MAG Transportation Policy Committee, approval from the
MAG-appointed Regional Council, and successful passage
of federally required air quality conformity tests. The plan
includes only projects for which funding is available or is
reasonably expected. Every 5 years through the life of the
plan, the RTP will be reevaluated, giving consideration to new
information, RTP adjustments, and relevant new studies.
•
· safety and technology
improvements
· regional bike path systems
· improved pedestrian connections
The RTP is an integrated, multimodal plan—meaning planned improvements made to one element of the regional
transportation system provide benefits to and improve operation of the entire system.
➤➤ how
much of the historic growth occurred without
the presence of a freeway system
➤➤ how
this growth, in turn, has driven the need for
transportation infrastructure
➤➤ how
a major transportation facility would be part
of an integrated response to both historical and
projected growth
What is the MAG regional travel
demand model?
The traffic assessment for the Study
Area employed the MAG travel demand
model (TransCAD software platform), as
certified by FHWA and reviewed by the
U.S. Environmental Protection Agency
(EPA) for air quality conformity. The
model projects demand for multiple modes
of travel, including automobile, bus, and
light rail. Key model inputs used to forecast
travel demand included:
• socioeconomic data based on the adopted
general plans of MAG members,
along with population and economic
forecasts and the existing and planned
transportation infrastructure as identified
by MAG members
• the anticipated average number of vehicle
trips within the region (including those
to and from the region’s households) on
a daily basis (this number is monitored
regularly by MAG)
• the distribution of transportation modes
used by travelers in the MAG region (also
monitored regularly by MAG)
• the capacity of the transportation
infrastructure to accommodate regional
travel
• the future transportation infrastructure
established using RTP-planned projects
and improvements and from known
arterial street network improvements
assumed to be made by the County, Cities,
and private developers
1
1-6
Chapter 1
•
Purpose and Need
South Mountain Freeway (Loop 202) DEIS and Section 4(f) Evaluation
Figure 1-2 Maricopa Association of Governments Regional Freeway and Highway System, 1985 and 2003
1
MAGa Regional Transportation Plan
Freeway Program as depicted in 2003
to Flagstaff
CAVE CREEK
Dixileta Drive
Patton Road
Jomax Road
Happy Valley Road
Pinnacle Peak Road
51
GLENDALE
303
LOOP
PHOENIX
Pima Freeway
101
101
PARADISE
VALLEY
LITCHFIELD
PARK
Salt River
Pima-Maricopa
Indian Community
Phoenix Sky Harbor
International Airport
Papago
10 Freeway
LOOP
202
Hohokam
Freeway
M
30
MESA
To be named
LOOP
Red Mountain Freeway
Gila River
Indian Community
South Mountain
Freeway
60 Superstition
Freeway
GUADALUPE
LOOP
101
Phoenix South
Mountain Park/Preserve
Price
Freeway
Hohokam
Expressway
GILBERT
Maricopa
10 Freeway
LOOP
202
Superstition Freeway
Santan Freeway
Sierra Estrella
Note: Location of South Mountain Freeway is
being addressed in the DCRb/EISc study
process currently underway that is
considering multiple location options.
Santan
Freeway
QUEEN
CREEK
MARICOPA COUNTY
environmental impact statement
Ray Road
Williams Field Road
Pecos Road
Germann Road
Queen Creek Road
Ocotillo Road
Chandler Heights Road
Riggs Road
Hunt Highway
McQueen Road
Cooper Road
Gilbert Road
24th Street
32nd Street
40th Street
48th Street
56th Street
Kyrene Road
Rural Road
27th Avenue
19th Avenue
7th Avenue
7th Street
16th Street
51st Avenue
43rd Avenue
35th Avenue
75th Avenue
67th Avenue
59th Avenue
PINAL COUNTY
91st Avenue
83rd Avenue
Bullard Avenue
Litchfield Road
Dysart Road
El Mirage Road
Perryville Road
Citrus Road
Cotton Lane
Sarival Avenue
Reems Road
c
Williams Gateway
Freeway
CHANDLER
McClintock Drive
Price Road
Dobson Road
Alma School Road
Arizona Avenue
design concept report
Baseline Road
Guadalupe Road
Elliot Road
Warner Road
24
Avondale Boulevard
107th Avenue
99th Avenue
b
Thomas Road
McDowell Road
McKellips Road
Brown Road
APACHE University Drive
JUNCTION Broadway Road
Southern Avenue
Red Mountain
Freeway
TEMPE
5 miles
Maricopa Association of Governments
Indian Bend Road
McDonald Drive
Chaparral Road
Indian School Road
AVONDALE TOLLESON
143
5 miles
Thunderbird Road
Cactus Road
Shea Boulevard
Pima
Freeway
n
so
th
ountain Freeway
LOOP
Agua Fria
Freeway
FOUNTAIN
HILLS
SCOTTSDALE
c
Tu
Maricopa
Freeway
Piestewa
Freeway
60 Grand
Avenue
GOODYEAR
Approximate scale
1
EL MIRAGE
YOUNGTOWN
202
Source: Maricopa Association of Governments, 1985a
a
SURPRISE
to
Sky Harbor
Expressway
u
So
1
McDowell
Mountains
Sossaman Road
Hawes Road
Ellsworth Road
Crismon Road
Signal Butte Road
Meridian Road
ay
arkw
ak P
w Pe
Squa
ay
sw
es
Agua Fria Freeway
pr
Ex
Approximate scale
PEORIA
Baseline Road
Sky Harbor
Airport
Papago Freeway
“Action”
as proposed
in 1985
Maricopa County line
Freeway proposed in 1985
McDowell Road
Existing freeway
Van Buren Street
Buckeye Road
Lower Buckeye Road
BUCKEYE
Broadway
Road
Southern Road
Pima Freeway
Black Canyon Freeway
Estrella Freeway
nd
ra
G
Paradise
Parkway
Gila River Indian Community boundary
as depicted
in 1985
Thomas Road
Agua Fria Freeway
Grand Avenue corridor
Black Canyon
Greenfield Road
Higley Road
Recker Road
Power Road
y
eewa
Existing freeway
17 Freeway
Deer Valley Road
Beardsley Road
Union Hills Drive
Bell Road
Greenway Road
Thunderbird Road
Cactus Road
Peoria Avenue
Olive Avenue
Northern Avenue
Glendale Avenue
Bethany Home Road
Camelback Road
Proposition
300 Freeway
Plan
Indian School
Road
Price Freeway
lla Fr
Estre
Planned freeway
Lindsay Road
Val Vista Drive
Note: The graphic below depicts the freeway plan
as shown to voters in 1985.
CAREFREE
Source: Maricopa Association of Governments, 2003; extrapolated analysis
Since 1985, the Maricopa Association of Governments Regional Freeway and Highway System has been constructed in reaction to economic and population growth. The South Mountain Freeway has remained an integral part of the region’s planned
freeway system—a combination of loop or belt routes and freeway arteries to, from, and around the urban core. The general location for the South Mountain Freeway has remained unchanged since 1985. The inset portrays the map conveyed to
Maricopa County voters pertaining to the passage of Proposition 300 in 1985 (see sidebar on page 1-9 regarding Proposition 300).
South Mountain Freeway (Loop 202) DEIS and Section 4(f) Evaluation
Chapter 1
Figure 1-3 Westward Ho Hotel, 1939
•
1-7
Purpose and Need
Figure 1-4 Growth Rates, 1950–2000
Millions
20
What kind of travel occurs on
roads in the MAG region?
a
Vehicle miles traveled
People
Jobs
Housing units
Millions
20
15
15
Advent of
affordable air
conditioning
Voters reaffirm
support for continued
implementation
of the MAGb
Regional Transportation Plan
by passage of
Proposition 400
Source: www.acmeron.com
As photographed in 1939, the Westward Ho Hotel depicts some of the initial tourism infrastructure in Phoenix.
From the city’s inception to the mid-1900s, resources
specific to the region and its strategic location drove
growth in the valley. Agriculture, mining, and product
distribution drove economic opportunity and population
growth during this period. In the early 1900s,
completion of a series of dam projects resulted in
controlled flows of the Salt River that allowed the
community’s agricultural industry to prosper. This era
was a turning point in the area’s economic base:
➤➤ Additional
rail lines were completed, allowing other
industries to settle in the region.
➤➤ Because of the area’s desirable climate and desert
setting, tourism was established as a primary economic
force, as evidenced by the openings of the Arizona
Biltmore Hotel and the Westward Ho Hotel in 1929
(see Figure 1-3), which coincided with the first
scheduled commercial flights between Los Angeles and
Phoenix. Tourism remains a key economic driver.
➤➤ Climate
and terrain also made the region suitable
for military training purposes. In response to the
World Wars, military facilities such as Luke Field,
Williams Field, Falcon Field, and related ground
training centers were built in the area.
➤➤ In
1948, Motorola opened its first Phoenix research
and development center for military electronics.
Other related businesses (e.g., Intel, McDonnell
Douglas) later established operations in the area.
10
9
By 1950, 105,000 people lived in Phoenix, with
thousands more settling adjacent to its city limits. From
approximately 1900 to 1950, the population had grown
by more than 1,800 percent. During that time frame,
automobiles became more affordable. The arterial street
network grew in support: in 1950, 311 miles of the
arterial street grid had been developed.
8
While the region remained a popular and desirable place
to live, certain factors continued to inhibit the rate of
growth. This changed, starting in the 1950s:
4
7
6
5
3
➤➤ The
use of affordable air conditioning in homes
and businesses became widespread and dramatically
increased the livability of the area. In 1959 alone, the
city of Phoenix experienced more construction than
in the previous 30 years.
Federal-Aid Highway Act of 1956 called for the
creation of the nation’s 42,500-mile national Interstate
Highway System (it would not be until 1990 that
2
Completion of
Interstate 10 through
the city of Phoenix
10
MAG Regional
Freeway and
Highway System
is approved by
voters in 1985
by passage of
Proposition 300
Construction
of the Central
Arizona Project
is approved
9
8
7
Motorists in the MAG region have different
purposes for traveling on the region’s road
network. Generally, travel in the MAG
region can be categorized into three travel
types:
• Local travel is generally short trips to
nearby residences, businesses, or some
centers of “activity.” Local travel makes up
a large portion of the total travel because of
the higher frequency of these trips. Local
travel is predominantly served by arterial
streets and neighborhood collector streets.
• Regional travel is generally longer trips to
regional employment and entertainment
centers. Commuting is often associated
with regional trips. Regional travel makes
up a large portion of the total travel in
the MAG region. Regional travel is
predominantly served by freeways and
secondarily by major arterial streets.
• Intrastate and interstate travel generally
includes the longest trips between major
population centers across the state and
to other states. This form of travel is
predominantly served by Interstate and state
highways.
Road networks in metropolitan areas are
often planned and designed to accommodate
these different travel needs.
6
5
4
3
Federal-Aid
Highway
Act of 1956
is enacted
2
1
1
0
➤➤ The
2010 2020 2030
2005
2035
1950 1960 1970 1980 1990 2000
0
a
v ehicle miles traveled reduced to one-tenth of their actual values
to facilitate comparison of growth rates on the same axis
b
Maricopa Association of Governments
Sources: 1950–2000 U.S. Census;
Maricopa Association of Governments, 2007a and 2009b
In recent years, the Maricopa Association of
Governments region has maintained some of the
fastest population, housing, and employment
growth rates in the country. The growth rate of
vehicles miles traveled has, however, continually
outpaced these growth trends.
1
1-8
1
The National Highway System
The National Highway System consists
of roadways important to the nation’s
economy, defense, and mobility. It features
the following subsystems:
• Interstate: The Eisenhower Interstate
System of highways retains its separate
identity within the National Highway
System.
• Other principal arterials: Highways in
rural and urban areas that provide access
between an arterial and a major port,
airport, public transportation facility, or
other intermodal transportation facility.
• Strategic Highway Network: A network of
highways that is important to the United
States’ strategic defense policy and that
provides access, continuity, and emergency
capabilities for defense purposes.
• Major strategic highway network
connectors: Highways that provide access
between major military installations
and highways in the Strategic Highway
Network.
• Intermodal connectors: These highways
provide access between major intermodal
facilities and the other four subsystems
making up the National Highway System.
Within Arizona, portions or all of US 60,
US 89, US 93, US 95, and US 160; portions
of SR 85, SR 87, SR 90, SR 95, and
SR 260; and the entire Regional Freeway
and Highway System are important and
substantial links in the National Highway
System.
For further information, see the Web site,
.
Chapter 1
•
Purpose and Need
the region would receive its full benefit, with the
completion of I-10 through central Phoenix).
➤➤ In
1968, a bill approving the construction of the
Central Arizona Project was signed, essentially ensuring
a long-term supply of water to central Arizona.
With the culmination of enhanced livability, improved
access, and assurance of long-term water supply, the
population in Maricopa County reached about 700,000
in 1960, just under 1 million in 1970, and just over
1.5 million in 1980 (see Figure 1-4)—all of this growth
occurred without the presence of a single freeway. To
summarize, from the early 1950s to the mid-1990s,
population grew by over 500 percent. (The population
in the United States as a whole grew by approximately
70 percent during this time period.)
To address transportation needs in response to
the growth, the system of local arterial streets was
continually expanded. But growth in the latter half
of the 1900s created new challenges—ones that were
regional in context. In response, MAG was formed.
One of these regional challenges related directly to
transportation. With growth, mobility needs expanded
from local and interstate to include regional travel (see
sidebar regarding travel in the region on previous page).
In fact, since the 1940s, annual growth in vehicle miles
traveled (VMT, see sidebar on page 1-13) in the MAG
region has continued to exceed population growth (see
Figure 1-4). The arterial street network that had served
transportation needs well was no longer able to meet all
the needs and demands of the driving public.
With the ongoing construction of the nation’s Interstate
Highway System, the concept of a circumferential, or loop,
freeway system around the city of Phoenix was introduced.
In 1960, a study was published by the U.S. Department
of Commerce Bureau of Public Roads for the Arizona
State Highway Commission. The study, A Major Street
and Highway Plan, Phoenix Urban Area, Maricopa County,
examined the relative merits of various major street and
highway layouts for the urban area and its surroundings. In
this study, recommendations were made to plan for outerbelt/loop-highway routes (over the existing arterial street
grid) to collect and distribute external and regional traffic
from other elements of the transportation system.
South Mountain Freeway (Loop 202) DEIS and Section 4(f) Evaluation
The challenge before MAG members was to design
an integrated intermodal transportation network to
accommodate the region’s future transportation needs.
In the early 1980s, planners from the local jurisdictions
that compose MAG membership evaluated transportation
needs in the region. The need for a major transportation
facility in the Study Area was first identified in the 1983
Southwest Area Transportation Study. In 1985, the MAG
Regional Council recommended the final elements of a
freeway system to go to the voters for funding through a
one-half cent sales tax.
The 232-mile freeway system proposed in 1985 eventually
became the Regional Freeway and Highway System. Not
unlike many urban freeway systems being planned and
constructed in several major cities across the country,
the proposed system was to be a series of belt, or loop,
highways around the major urban core with major freeway
arterials into the urban core of Phoenix. As part of the
National Highway System (see sidebar on this page), the
system would supplement the urban Interstate Highway
System’s arterial function—mainly, the role served by I-10
in moving large volumes of intracity and regional traffic.
When integrated with the urban Interstate system and
major arterial street system, the loop highways would
complete a surface transportation system that would:
➤➤ reduce
increasing congestion on the Interstate
Highway System in the urban core
➤➤ facilitate
and more effectively distribute the regional
movement of goods and delivery of services
➤➤ more
evenly distribute traffic on the major arterial
street grid and reduce regional traffic using the grid
➤➤ better
serve already-occurring regional traffic
➤➤ provide
➤➤ provide
an alternate route for pass-through traffic
an integrated intermodal network of
freeways strategically located to accommodate local
and regional land use planning
➤➤ enhance
local mobility by removing regional traffic
from the local road network
➤➤ create
infrastructure to support the regional bus
transit system component of the intermodal LongRange Transportation Plan (LRTP) (MAG 2001a)
➤➤ encourage
and direct planned growth
A major element of the region’s freeway loop, or beltway
system, traversed the Study Area and was originally
called the Southwest Loop. It was an integral piece of
the Regional Freeway and Highway System approved by
Maricopa County voters in the 1985 one-half cent sales tax
referendum. The Regional Freeway and Highway System
plan was included as a key component in the LRTP.
Subsequent location/design and State-level environmental
studies were conducted by ADOT for Regional Freeway
and Highway System segments. Additional studies were
prepared to examine other alternatives in the Study Area.
Examples of other studies include:
➤➤ Southwest Loop Highway (SR 218) Final
Environmental Assessment (ADOT 1988a)
➤➤ Southwest Loop Highway (SR 218) Design Concept
Report (ADOT 1988b)
➤➤ Alignment Recommendation, South Mountain Corridor
Loop 202 (Arizona Transportation Group and South
Mountain Community Highway Association 1997)
The 1988 State-level environmental assessment (EA) and
design concept report (DCR) were prepared for what was
then known as the South Mountain Freeway. This same
route (now designated as part of SR 202L) was approved
by the State Transportation Board (STB) in 1988. All
these studies provided sufficient design detail to establish
an adopted and publicized location for the freeway. The
1988 freeway plan outlined a six-lane freeway.
The Regional Freeway and Highway System has been
constructed sequentially to meet the most pressing
transportation needs in the MAG region and as funds
have become available. Consequently, freeway construction
followed geographic patterns of development and
population growth. High-growth areas historically were
in the northeastern, northwestern, southeastern, and
central areas of the MAG region (see Figure 1-5). Available
funds were used to build Regional Freeway and Highway
System segments in those areas, and completing the
Regional Freeway and Highway System in the Study Area
(southwestern quadrant of the greater Phoenix metropolitan
area) has been a lower priority.
South Mountain Freeway (Loop 202) DEIS and Section 4(f) Evaluation
Chapter 1
•
Purpose and Need
1-9
Figure 1-5 Historic and Projected Population Distribution, 1955–2030, Phoenix Metropolitan Area
1
1955
1975
2000
2010 (projected)
2030 (projected)
Source: Maricopa Association of Governments, 2008a; used with permission
Red area depicts areas of high population density. Population has spread throughout the region, starting from downtown Phoenix, moving to the north and east and eventually to the west. This more recent westward trend in the geographic distribution
of population densities is expected to continue. For additional information regarding population growth in the region, see the section, Population and Employment, beginning on page 4-20. (The black dashed and solid lines depict the locations of
regional and Interstate freeways in the region. They are shown here as locational aids to the reader.)
During initial implementation of the Regional Freeway
and Highway System, population growth in the MAG
region continued at a rapid pace. From 1980 to 2005,
the population of Maricopa County more than doubled,
from 1.5 million to 3.7 million. The MAG region has
been one of the fastest-growing metropolitan areas in the
United States; by population, Phoenix is the fifth-largest
city in the country and the region ranks as the 12th-largest
metropolitan area in the country (U.S. Census Bureau 2011).
The number of housing units and the employment base
in the region have maintained a similar growth rate. As
of 2005, almost 1.5 million housing units (including homes
and apartments) were in Maricopa County (MAG 2007a).
Employment in Maricopa County increased at a high rate.
Between 1980 and 2005, total employment increased by
over 1 million jobs, from 690,000 to 1.7 million jobs. In
general, the employment base in the region has outpaced
the national average. For example, for the 10‑year period
beginning in 1984, employment in the region increased
by 49 percent while the national gain was 24 percent.
Employment growth rates from 1970 through the
mid‑1980s (the period prior to the conception of the
Regional Freeway and Highway System) were equal to the
growth rates from 1985 to 2005.
Projections of what the region is expected to look like
in terms of population, housing, and employment are
described in the section, Need Based on Socioeconomic
Factors, beginning on page 1-11.
While growth continued, ADOT, on behalf of MAG,
moved toward completing the Regional Freeway and
Highway System. By 2001, ADOT had completed
120 miles of the originally planned 232-mile Regional
Freeway and Highway System. Further, the one-half
cent transportation sales tax approved in 1985 was set
to expire at the end of 2005. In response, in late 2004,
a referendum (Proposition 400) to extend the one-half
cent sales tax for another 20 years was placed before and
approved by Maricopa County voters (see sidebar regarding
Propositions 300 and 400 on this page). The funds to be
generated by this tax are planned to ensure completion of the
remaining segments of the Regional Freeway and Highway
System and to support other regional transportation projects
as programmed in the RTP. The 2003 RTP and its annual
updates serve as the “next generation” of the LRTP.
In this context, the following conclusions can be made:
rapid growth in population, employment,
and housing has been driven by mild climate,
affordable cost of living, and economic opportunities.
➤➤ With regional growth came regional mobility needs.
Motorists who earlier had only local or intra-/
interstate travel needs wanted to be able to travel
efficiently and conveniently within the region.
➤➤ Historical,
region’s transportation infrastructure evolved in
response to growth to one that included a regional
freeway system to meet these regional needs.
➤➤ The
➤➤ Planning
continued for one of the “missing”
Regional Freeway and Highway System segments:
the South Mountain Freeway.
CONTEXT OF THE PROPOSED
ACTION IN CURRENT REGIONAL
TRANSPORTATION PLANNING
According to Arizona Revised Statutes
(A.R.S.) § 42‑6105E, the Transportation Policy
Committee (TPC) is mandated to develop a plan
to readdress long-range transportation needs in the
region and to do so in cooperation with the Regional
Public Transportation Authority (RPTA) and ADOT.
The TPC is a public-private partnership established
by MAG. It consists of a cross section of MAG
member agencies and representatives from business,
transit, freight, the Citizens Transportation Oversight
Committee, and ADOT. From TPC recommendations,
the RTP evolved; it was submitted to the MAG
Regional Council for final adoption in 2003. In
preparing the RTP, MAG offered 150 public input
opportunities and held 117 agency meetings and
173 stakeholder meetings. Opportunities for public input
included expert panels, focus groups, special events and
workshops, and public hearings (see the MAG Web site,
, for additional information).
What do the results of
Propositions 300 and 400 tell us?
Voter approval of the one-half cent sales
tax in 1985 (Proposition 300) and
its continued endorsement in 2004
(Proposition 400) underscore continued
public support for investment in regional
transportation projects. Results from
the Maricopa County Official Canvas
(Maricopa County 2004a) indicate voters
in 90 percent of the county’s 1,058 voting
precincts voted in favor of Proposition 400
and the projects it would fund.
Voters in 81 percent of the 31 voting precincts
in the Study Area favored Proposition 400
and the projects it would fund.
1-10
1
What are TSM and TDM?
Transportation system management
(TSM) and transportation demand
management (TDM) are programs and
strategies that seek to maximize existing
roadway efficiency without incurring the
costs of substantial physical improvements.
TSM attempts to maximize the safety and
efficiency of the existing transportation
network using such traffic management
tools as electronic message signs, signals
to meter traffic flow at on‑ramps, closed
circuit television cameras, and vehicle
detectors.
TDM seeks to reduce travel demand in
the existing transportation network by
promoting alternative modes of travel,
including carpooling, van pooling,
walking, bicycling, alternative work
schedules and compressed work schedules
to reduce the number of trips, and
telecommuting.
Chapter 1
•
Purpose and Need
South Mountain Freeway (Loop 202) DEIS and Section 4(f) Evaluation
Table 1-2 shows the highlights of the RTP. Three
agencies implement three major RTP programs: ADOT –
freeway/highway program; RPTA – transit program; and
MAG – arterial street program. Each agency is required
to regularly report on the status of the projects within its
program and update revenue projections and cost opinions
so that the programs remain fiscally balanced.
time, the cost opinions have increased to approximately
$16 billion, with $2.7 billion obligated or spent to date.
With declining revenues and softer revenue projections,
it is anticipated that only $6.6 billion in revenues will be
collected through the end of the RTP horizon to fund the
remaining $13.2 billion in projects. That left a program
deficit of approximately $6.6 billion.
In 2009, MAG and ADOT began the process of making
a substantial update to the freeway program of the RTP
(the transit and arterial street programs underwent similar
reviews). The update became necessary in response to both
declining sales tax revenues resulting from the national
economic downturn and to rising project cost estimates
for the freeway program. Tentative Scenario for the MAG
Regional Freeway and Highway Program (MAG 2009a)
presents the bleak financial situation. The original,
2003 RTP balanced projected revenues and project
cost opinions at approximately $9.4 billion. Since that
The TPC held meetings throughout 2009 to discuss
options for bringing the freeway program into balance.
In developing its recommended scenario, the TPC
considered numerous options, including removing
projects, reprioritizing projects, scaling projects back, and
deferring projects outside of the 2026 funding horizon.
The recommended changes were presented at a public
hearing on October 13, 2009, and adopted by the MAG
Regional Council later that month. The recommended
scenario maintained the core enhancements and priorities
of the RTP and balanced the budget by deferring a
number of projects to an “unfunded” status beyond the
plan’s funding horizon.
Table 1-2
Regional Transportation Plan Highlights
●
Freeway
Arterial
Street
System
●
●
●
●
●
Transit
Plan Benefit
Highlights
Elementa
●
●
Add new freeway corridors, providing approximately
490 lane-miles
Improve existing freeways—add 530 lane-miles of general
purpose lanes and 300 lane-miles of HOVb lanes
Add through- and turning lanes to existing streets with one to
three lanes in each direction
Improve intersections
Construct new arterial street segments
Add new 58-mile light rail system through central MAGc region
Expand bus rapid transit and regional bus grid
Expand paratransit, rural/nonfixed-route transit and commuter
van pools
Specific
●
●
●
●
●
●
●
●
●
TSM/TDMd
a
b
The projects that remained funded by the RTP, including
the proposed action, were repackaged with new budgets
and cost savings recommendations (MAG 2010a). The
RTP 2010 Update included a fiscally balanced plan for
completing the identified freeway/highway, arterial
street, and transit programs (MAG 2010a). The cash
flow projections continued to be reviewed annually.
In 2012, a similar rebalancing effort was completed to
address an additional projected shortfall of $390 million.
Program changes were approved by the MAG Regional
Council in May 2012. The approved program includes
$1.9 billion for design, right-of-way, and construction
of the proposed action. Also of note is that funding for
project-related activities are included in the immediate
5-year programs identified in the regional Transportation
Improvement Program (TIP) as well as the State
Transportation Improvement Program.
●
●
Promote ridesharing, van pool programs, telecommuting
Increase real-time traffic management technology
●
Increase Regional Freeway and Highway
System capacity
Reduce travel time and delay
Improve regional continuity, connectivity,
and efficiency
Reduce travel time and delays
Improve local continuity, connectivity,
and efficiency
Shorten bus wait times
Lengthen duration of bus service
Improve regional transit continuity,
connectivity, and efficiency
Reduce travel demand
Improve Regional Freeway and Highway
System, arterial street network, and transit
efficiency
Overall
●
●
●
Form integrated transportation system and
transportation services to provide accessibility,
mobility, and modal choice for residents,
businesses, and the economic development of
the region
Create integrated transportation system and
services with safety as a core value and feature
Plan and implement improvements for each
modal and system element to augment and
enhance the service performance of other
Regional Freeway and Highway System
elements
F eatures listed in this table are not comprehensive; the reader is referred to the Regional Transportation Plan for all proposed plan improvements. See .
high-occupancy vehicle c Maricopa Association of Governments d transportation system management/transportation demand management—see sidebar on this page
South Mountain Freeway (Loop 202) DEIS and Section 4(f) Evaluation
Chapter 1
•
Purpose and Need
1-11
NEED AND PURPOSE FOR THE PROPOSED ACTION
The section, Context of Purpose and Need in the EIS
Process, beginning on page 1-1, provides several
elements useful in explaining the purpose and need for
a proposed action. The proposed action is needed to
serve projected growth in population and accompanying
transportation demand and to correct existing and
projected transportation system deficiencies. These
needs are discussed in the following sections. The
purpose of the proposed action—implementation of a
major transportation facility—is to meet these identified
needs.
In response to the projections, MAG developed the
RTP to specify what future transportation investments
would be needed in the region through 2026. Almost
50 percent of the projected increases in population,
housing, and employment from 2005 to 2035 are
expected in 4 of 14 geographic areas, as shown
in Figure 1-7, for the entire MAG region. These
4 contiguous areas are located primarily in the southern
and southwestern portions of the MAG region.
NEED BASED ON SOCIOECONOMIC
FACTORS
Projected Growth in Population, Housing,
Employment, and Vehicle Miles Traveled
Based on the above, the following conclusions are
reached:
MAG projections (conducted in collaboration with
the Arizona Department of Economic Security)
indicate Maricopa County’s population will increase
from 3.7 million in 2005 to 6.5 million in 2035
(MAG 2009b) (see Figure 1-6). This equates to almost
100,000 additional people per year. In turn, the housing
unit numbers are projected to maintain a similar growth
rate to meet population growth demand. The number of
housing units is projected to increase from 1.5 million
in 2005 to 2.7 million in 2035.
MAG regional employment is projected to increase
at a high rate. Similar to the county’s population,
employment is projected to increase from 1.7 million
jobs in 2005 to 3.6 million jobs in 2035.
Although growth trends have been relatively flat since
2007, the long-term rates of population, housing, and
employment growth experienced since the 1950s are
projected to continue through 2035 (see sidebar on this
page). And as has been the case in the past, VMT are
projected to annually outpace the three socioeconomic
trends discussed in this section (Figure 1-6).
How will the economic downturn
affect growth rates?
Figure 1-6 Projected Growth Rates, 2000–2035
Millions
20
Vehicle miles traveleda
People
Jobs
Housing units
Millions
20
Relationship of the Proposed Action
to Projected Growth
15
15
➤➤ Socioeconomic
forecasts show population, housing,
and employment increasing at high rates. Projections
for 2035 are of a population of 6.5 million, housing
of 2.7 million dwelling units, and an employment
level of 3.6 million jobs (MAG 2009b).
➤➤ Increases
in VMT are expected to outpace growth of
the three socioeconomic trends.
10
➤➤ Almost
50 percent of the projected regional growth is
expected to occur in areas that would be immediately
served by the proposed action.
10
9
9
8
8
➤➤ Planned
multimodal, integrated transportation
improvements in the RTP are fiscally constrained
responses to past and projected growth in the
MAG region.
7
7
6
6
➤➤ The
identified Study Area is an appropriate area for
assessing the need for a major new transportation
infrastructure project when considering past and
existing regional transportation planning and in the
context of projected socioeconomic trends in the
southwestern MAG region.
5
5
4
4
3
3
2
2
1
1
0
1950 1960 1970 1980 1990 2000
0
2010 2020 2030
2005
2035
a
v ehicle miles traveled reduced to one-tenth of their actual values
to facilitate comparison of growth rates on the same axis
Sources: 1950–2000 U.S. Census;
Maricopa Association of Governments, 2007a and 2009b
The worldwide recession that began in
late 2007 has generated a sustained and
substantial downturn in growth rates
for new housing and employment across
the United States. While opinions and
predictions vary, economic recovery may not
be well underway until 2012 or later. The
recession may be the worst since the Great
Depression of the 1930s.
Arizona has particularly suffered the effects
of this recession because, beginning in
the early 2000s, Arizona in general and
Maricopa County specifically enjoyed some
of the fastest population, housing, and
employment growth rates in the country.
Local economies suffering the most in the
current recession are those, like Phoenix,
that enjoyed a boom period linked to robust
housing markets, became overbuilt, and are
now stagnant. Past recessions, such as the
savings and loans scandals of the late 1980s,
substantially impaired the region’s growth.
Many savings and loan institutions closed,
commercial real estate became drastically
overbuilt, and businesses left Arizona daily.
Yet, in a matter of years, dramatic economic
growth resumed.
Because the need for the proposed action
is predicated in part on projected growth,
one might conclude the current recession
will reduce that need. An economic
downturn associated with a given recession
is, however, generally considered a shortterm phenomenon with respect to the
longer-term planning horizon established
for the proposed action. As described in
the main text and as shown in Figure 1-4,
socioeconomic indicators have steadily and
consistently increased in the region since the
early 1900s. The critical factors underlying
these indicators remain unchanged.
Population, housing, and employment
growth rates are projected to continue to rise
through 2035. As with the historical trend,
vehicle miles traveled are projected to outpace
these socioeconomic growth trends.
1
1-12
1
How does growth in adjacent
counties affect traff ic volume
projections?
Growth in areas outside the MAG
region has become an important factor in
forecasting travel demand in the MAG
region. Growth in Pinal and Yavapai
counties, for example, contributes to
increased traffic in the MAG region. To
help assess the effects of external travel
on the regional travel demand model, a
study was conducted in 1999 (Phoenix
External Travel Summary [MAG 2001b]).
Since the study, the region’s travel demand
model network has been extended to
include a large portion of Pinal County,
including Queen Creek, Apache Junction,
East Mesa, Casa Grande, and Maricopa.
A travel study (MAG and PAG External
Travel Study [MAG 2009c]) was conducted
in 2008 using video cameras and license
plate-matching technology to assess
the number of external-to-internal
(commuting) trips and the externalexternal (pass through) trips for passenger
cars and heavy trucks.
The results of this and many other studies
help analysts predict travel demand in the
MAG region.
Chapter 1
•
Purpose and Need
South Mountain Freeway (Loop 202) DEIS and Section 4(f) Evaluation
Figure 1-7 Geographic Distribution of Projected Growth by Subregion, 2005–2035
Subregion
Far Southwest Valley
PEORIA
+236
+121
SURPRISE
+452
+191
+80
+49
North Valley
Northeast Valley
TOLLESON
+684
+234
Far East Valley
PARADISE
VALLEY
+23
+30
+141
+104
+296
+251
AVONDALE
Northwest Valley
SCOTTSDALE
GLENDALE PHOENIX
GOODYEAR
Far Northwest Valley
+225
+125
+208
+135
FOUNTAIN
HILLS
East Valley
+1
+1
North Central Phoenix
TEMPE
Central Phoenix
+100
+181
+127
+126
South Scottsdale/Paradise Valley
MESA
Central West Valley
Southwest Valley
GILBERT
CHANDLER
+7
+19
Ahwatukee/Gila River Indian Community
+283
+285
Proposed action
Chandler/Gilbert/Queen Creek
Proposed action
Projected increase in population 2005–2035 (000s)
Projected increase in employment 2005–2035 (000s)
QUEEN CREEK
Population (000s)
Activity Area
Not to scale
2005
2035
Central West Valley
513
809
Southwest Valley
125
Employment (000s)
Projected Increase
2005
2035
296
127
378
251
809
684
48
282
234
82
89
7
26
45
19
588
871
283
246
531
285
Total for the proposed action
activity area
1,308
2,578
1,270
447
1,236
789
Total Maricopa County
3,681
6,545
2,864
1,748
3,600
1,852
36%
39%
44%
26%
34%
43%
Ahwatukee/Gila River Indian
Community
Chandler/Gilbert/Queen Creek
Percentage contribution –
proposed action corridor
activity area
Projected Increase
Source: Maricopa Association of Governments, 2007a and 2009b; extrapolated analysis
Almost 50 percent of the projected population and employment growth in the Maricopa Association of Governments region is expected to occur in areas that would be immediately served by the
proposed action.
South Mountain Freeway (Loop 202) DEIS and Section 4(f) Evaluation
NEED BASED ON REGIONAL
TRANSPORTATION DEMAND
AND EXISTING AND PROJECTED
TRANSPORTATION SYSTEM
CAPACITY DEFICIENCIES
Every day, people travel to and from various destinations
throughout the MAG region. The purposes of the
travel vary—work-related, personal, and the movement
of goods and delivery of services. People in the region
use various means for travel. Cars, buses, bicycles, and
walking are all forms, or modes, of travel occurring
every day in the MAG region. Taken in its entirety,
the amount of travel occurring in the MAG region
is referred to as transportation “demand.” To allow
individuals to meet the purposes of their travel with any
travel mode(s) chosen, the region must have appropriate
transportation infrastructure and systems in place. The
extent of transportation infrastructure and the number
of systems in place to accommodate travel demand are
referred to as the transportation “capacity.”
Taken in its entirety, the MAG region transportation
network (including freeways, arterial streets, etc.) has
the ability to accommodate a certain volume of travel
during a given time frame and still manage to operate
at an acceptable level of efficiency. Once that volume
is exceeded (or, demand exceeds capacity), the network
begins to operate inefficiently. This is referred to as
“capacity deficiency.”
If the transportation network is, or is projected to
be, deficient in its capacity and unable to efficiently
serve existing and future transportation needs in the
MAG region, analysts would determine what aspects
of the network are, or are projected to be, deficient
(e.g., arterial street network, Regional Freeway and
Highway System, a combination) and where in the
system the deficiencies would occur. To make the
assessment, analysts would need to know:
➤➤ existing
➤➤ the
and projected demand for the network
types, modes, lengths, and durations of travel
that occur in the region today and in the future
(e.g., local, regional, interstate, a combination)
➤➤ where
the travel occurs now and would occur in
the future
If deficiencies are found in the network, analysts can
suggest the types of improvements to the region’s
transportation network necessary to address the
deficiencies and test the suggested improvements to
assess their effectiveness. The tools used by analysts to
assess the need for improvements are summarized in
Table 1-3.
Chapter 1
Table 1-3
Traffic Volumes in the Study Area
and Immediate Surroundings
The transportation network in the Study Area currently
and in the future would contain mostly arterial streets.
Exceptions would be sections of I-10 (Papago and
Maricopa freeways) and SR 101L (Agua Fria Freeway)
located along the periphery of the Study Area.
Average daily traffic (ADT) volumes at locations in and
around the Study Area for existing conditions (2010) and
future conditions (2035) are presented in Figure 1-8. The
upper portion of the figure shows the change in traffic
on representative segments of the Interstate and regional
freeways, while the lower portion shows the change
in traffic on representative arterial street segments.
Freeways are intentionally designed to handle much
higher ADT volumes than arterial streets. Based on lane
capacities used in the MAG travel demand model, a
typical six-lane arterial street could carry 51,000 vehicles
per day (vpd), while a typical six-lane freeway could
carry 165,000 vpd. Traffic for the two types of facilities
is presented on a single scale to spotlight this difference
in overall capacity and utility.
The 2035 network includes all of the improvements from
the RTP except for the proposed action in the Study
Purpose and Need
1-13
Traffic Analysis Tools
Analysis Toola
Issue Identification
Tool Purpose
●
●
Is there currently a
deficiency in network
capacity and will
there be a deficiency
in future network
capacity?
Existing and Future Traffic Conditions
in the Study Area and Immediate
Surroundings
The following presents operational characteristics of the
existing and future road network in the Study Area and
surroundings without a major transportation facility in
place. Assessment of traffic volumes, traffic conditions,
travel distributions, capacity deficiency, and travel times
provides analysts a basis for evaluating the need for a
major transportation facility in the Study Area.
•
●
●
●
●
Existing and Future Traffic
Volume Projections (Travel
Demand Analysis) (TransCADb)
Level of Service Analysis
(TransCAD)
Trip Distribution (Cut-line
Analysis)
Existing and Projected Travel
Time and Congestion Analysis
(TransCAD)
Trip Distribution (Select Link
Analysis)
●
●
●
●
Establish overall demand for use of the
future network,c including mode, trip
type, and durations; determine capacity
deficiency of the network, including freeway,
arterial street, and modal deficiencies
Determine performance of the network in
terms of quality of service and efficiency
Evaluate traffic distribution between arterial
streets and freeways
Determine projected level of delay and
associated congestion
Identify origins and destinations of trips to
establish the types of trips occurring in a
given area of the MAGd region
a
nalytical tools are further described in the section, Key Traffic Modeling Definitions, on page 3-27.
A
TransCAD is the travel demand modeling software platform used by MAG.d
c
future transportation network analyzed without the proposed action
d
Maricopa Association of Governments
b
Area. Notable observations regarding the freeway traffic
volumes in Figure 1-8 include:
➤➤ On I-10 (Papago Freeway) between SR 101L
(Agua Fria Freeway) and Interstate 17 (I-17), at the
two locations shown (11 and 12), traffic is projected
to increase by 33,000 and 22,000 vpd, respectively,
between 2010 and 2035.
➤➤ Through
the downtown area (location 10), traffic
on I-10 is projected to increase by 38,000 vpd
between 2010 and 2035.
➤➤ Through
the “Broadway Curve” area (location 9),
traffic on I-10 is projected to increase by 103,000 vpd
between 2010 and 2035.
➤➤ On
I-10 (Maricopa Freeway) between US 60 and
SR 202L (Santan Freeway) (location 8), traffic is
projected to increase by 67,000 vpd between 2010
and 2035.
➤➤ Overall,
at the 13 freeway locations shown,
the average increase in traffic is 52,000 vpd,
representing an increase of approximately 28 percent
between 2010 and 2035.
Measurements of Traff ic
Regional travel is generally reported
in VMT because it combines the total
number of vehicles and the length of the
trip. This provides a true measure of the
total travel occurring in a large area.
The traffic on a road segment is generally
reported as ADT. The unit of ADT is
vehicles per day. Daily traffic gives an
overall metric for comparing different road
segments in a region.
Peak traffic is generally reported as
vehicles per hour. The LOS rating is based
on traffic conditions during the peak hour.
For more information on LOS, see the text
box on page 1-14.
1
1-14
1
Chapter 1
•
Purpose and Need
South Mountain Freeway (Loop 202) DEIS and Section 4(f) Evaluation
➤➤ The
What Is Level of Service?
Transportation analysts have developed a uniform way
of describing the overall quality provided by a given
transportation facility, service, or network. In 1965,
an LOS “report card” method was introduced, where
highway quality of service was “graded” using six letters,
“A” through “F,” with “A” being the best and “F” being
the worst. With the LOS approach, traffic engineers were
better able to explain operating and design concepts of
highways to the general public and elected officials. The
LOS letter approach is now commonly used throughout
the United States.
LOS is most often modeled during the morning and
evening commuting periods. These are the times when
most motorists are on the roads, when traffic volumes
are highest. As a result, the operational efficiency
of the network can be assessed under “worst-case”
conditions.
For the traffic analysis, widely accepted LOS
qualitative measures were applied to characterize
operational conditions of traffic flow. These measures
characterize traffic conditions using factors such as
speed and travel time, freedom to maneuver, traffic
interruptions, and comfort and convenience. For
freeways, LOS E describes operation at capacity.
Operational characteristics at this level are volatile,
because there are virtually no usable gaps in the
traffic. Vehicles are closely spaced, leaving little room
to maneuver at speeds that still exceed 45 miles per
hour (mph). Any disruption, such as vehicles entering
from a ramp or a vehicle changing lanes, can establish a
“disruption wave” that affects traffic flow. At capacity,
the traffic has no ability to dissipate even the most
minor disruption, and any incident can be expected
to produce a serious breakdown with extensive traffic
back-up. Maneuverability within the traffic stream
is extremely limited and the levels of physical and
psychological comfort afforded the driver are poor.
Because of this, most transportation planners strive to
design freeways to achieve LOS D or better.
Levels of service
LOS A
LOS B
highest percentage increase would occur
between Pecos Road and Wild Horse Pass Boulevard
on I-10 (Maricopa Freeway) (location 7).
The arterial street volumes shown in Figure 1-8
represent spot locations in the Study Area. Changes
between the 2010 and 2035 arterial street network would
be planned improvements to be made by the City of
Phoenix, Maricopa County, or by private developers
(with jurisdictional approval) to address local traffic
needs associated with future development. The change
in traffic volumes between 2010 and 2035 on the arterial
street network would vary throughout the Study Area.
Some locations may have large increases in projected
traffic volumes, others small, and some might even
experience reduced traffic. Projected traffic volumes
would likely vary because motorists may seek alternative
routes in response to changes in land use, such as
new construction or abandonment of employment,
commercial, or retail centers. When taken in its entirety,
traffic on the arterial streets in the Study Area would
increase at a rate comparable to that of the arterial street
network in the entire MAG region.
The largest change in traffic would be anticipated on
arterial streets that are:
LOS C
➤➤ located
in areas that are currently undeveloped but
are planned to be developed in the future
➤➤ currently
two lanes wide but are planned to be
widened to four, five, or six lanes in the future
From observation, traffic volumes are typically higher on
an arterial street when the street:
➤➤ is
closer to a major freeway
➤➤ has
more lanes provided in each direction and,
therefore, can accommodate more vehicles
LOS D
LOS E
➤➤ is
LOS F
Source: Arizona Department of Transportation, 2007b
located within urbanized areas or near areas where
land is subjected to more intensive uses
As a general observation, traffic volumes experienced on
arterial streets and freeway segments in the Study Area
are typical of volumes experienced throughout the
MAG region.
South Mountain Freeway (Loop 202) DEIS and Section 4(f) Evaluation
Chapter 1
•
Purpose and Need
1-15
Figure 1-8 Average Daily Traffic Volumes on Freeways and Arterial Streets (without the Proposed Action), 2010 and 2035
6
LOOP
Freeways
Black Canyon
17 Freeway
4
US 60a
5
b
SR 202L
Agua Fria
101 Freeway
13
12
Piestewa
Freeway
51
Papago
10 Freeway
SR 101Lc
10
11
SR 51d
e
I-17
9
30 To be named
60 Superstition
Freeway
1
8
I-10f
3
LOOP
Price
101 Freeway
Maricopa
10 Freeway
Approximate scale
LOOP
1
5 miles
7
2 202
Santan
Freeway
16
2. Priest Drive to Kyrene Road
37
3. Guadalupe Road to Elliot Road
31
4. Camelback Road to Bethany Home Road
30
5. Indian School Road to Camelback Road
10
6. Indian School Road to Camelback Road
40
7. Pecos Road to Wild Horse Pass Boulevard
65
8. Baseline Road to Elliot Road
28
10. 7th Street to 16th Street
14
11. 35th Avenue to 27th Avenue
12
12. 83rd Avenue to 75th Avenue
9
Communityh boundary to Pecos Road
Baseline Road to Dobbins Road
Buckeye Road to Lower Buckeye Road
Indian School Road to Thomas Road
174
172
7
11
67th
Avenue
Buckeye Road to Lower Buckeye Road
Van Buren Street to Buckeye Road
Thomas Road to McDowell Road
–3
6
–1
83rd
Avenue
Buckeye Road to Lower Buckeye Road
I-10 to Van Buren Street
Indian School Road to Thomas Road
115
10
4
Van Buren
Street
27th Avenue to 19th Avenue
59th Avenue to 51st Avenue
75th Avenue to 67th Avenue
43
–12
23
Buckeye
Road
35th Avenue to 27th Avenue
51st Avenue to 43rd Avenue
83rd Avenue to 75th Avenue
1
–2
20
Baseline
Road
19th Avenue to 7th Avenue
24th Street to 32nd Street
40th Street to 48th Street
78
34
11
Chandler
Boulevard
48th Street to I-10
40th Street to 48th Street
24th Street to 32nd Street
38
27
36
Pecos
Road
5 miles
U.S. Route 60 b State Route 202L (Loop 202)
i
average daily traffic
c
State Route 101L (Loop 101)
d
State Route 51
e
Interstate 17
f
Interstate 10
Arterial streets
2010 (color bars)
2035
–11
–11
101
32nd Street to 40th Street
Desert Foothills Parkway to 24th Street
17th Avenue to Desert Foothills Parkway
% change
in ADTi 0
Note: Volumes include general and high-occupancy vehicle lanes. The 2035 network includes all of the improvements from the
Regional Transportation Plan except for the proposed action.
a
2010
2035
35
51st
Avenue
Pecos Road
Freeways
35
9. 48th Street to Broadway Road
g
13. 115th Avenue to 107th Avenue
Chandler Boulevard
Approximate scale
1
40th Street
48th Street
17th Avenue
Baseline Road
Dobbins Road
24th Street
Southern Avenue
32nd Street
Van Buren Street
Buckeye Road
Lower Buckeye Road
Broadway Road
Desert Foothills Parkway
7th Avenue
51st Avenue
43rd Avenue
35th Avenue
27th Avenue
19th Avenue
75th Avenue
67th Avenue
59th Avenue
Bethany Home Road
Camelback Road
Indian School Road
Thomas Road
McDowell Road
83rd Avenue
Arterial streets
1. Rural Road to McClintock Drive
g
“Broadway Curve”
50
h
100
250
300
150
200
ADT volume (thousands of vehicles)
350
400
450
Gila River Indian Community
Source: Maricopa Association of Governments, 2010b; extrapolated analysis
Freeways are designed to handle much higher average daily traffic volumes than arterial streets. Regardless, high travel demand on Study Area freeway and arterial street segments is expected to continue through 2035.
1
1-16
1
Chapter 1
•
Purpose and Need
What is congestion?
Operational Conditions on Freeways
in the MAG Region
Congestion refers to undesirable traffic
conditions. Generally, congestion exists
when the LOS is E or F, when traffic on a
freeway is moving at an average speed of
45 mph or less, and/or the traffic flow is
often stop-and-go.
The previous section concluded that traffic volumes
would increase between 2010 and 2035 because of
increases in capacity and demand. The following text
describes how the changes in traffic volumes would affect
system efficiency in terms of LOS.
Existing and future road network and socioeconomic
conditions were modeled to determine operational
conditions on the existing and future road network.
Planned improvements from the RTP (excluding the
proposed action) and other planned improvements from
local, county, and private agencies make up the future road
network. The duration of current and projected LOS E or F
(congested) conditions on freeway sections in the MAG
region during the morning and evening commute periods
are shown in Figures 1-9 and 1-10, respectively.
In both periods in 2010, the region’s freeways are
noticeably congested and operate poorly.
Notable observations about the morning commute
(Figure 1-9) include:
➤➤ The
worst conditions are found with freeway traffic
inbound to downtown Phoenix.
➤➤ Congestion
(see sidebar on this page) lasts over
3 hours in some freeway sections, including
eastbound I-10 (Papago Freeway) approaching I-17,
westbound I-10 north of US 60 (the Broadway
Curve), and westbound I-10 between approximately
SR 143 (Hohokam Freeway) and 40th Street.
➤➤ Even
with RTP-planned improvements (without
the proposed action), congestion would continue to
worsen through 2035.
➤➤ Implementation
of RTP-planned improvements
(such as widening of I-10 and construction of the
SR 30 freeway) would result in only localized
improvement in operational performance
between 2010 and 2035.
Notable observations about the evening commute
(Figure 1-10) include:
➤➤ The
amount and duration of congestion on freeways
in the MAG region are substantially greater in
South Mountain Freeway (Loop 202) DEIS and Section 4(f) Evaluation
the evening than in the morning because more
non‑work-based trips are occurring (e.g., trips to
stores, restaurants, events).
➤➤ In
2010, congestion of more than 3 hours occurred
in outbound directions from downtown Phoenix on
almost every freeway. Conditions were especially
poor on I-10 north of US 60 (the Broadway Curve)
and in areas around system traffic interchanges
between I-10 (Papago Freeway) and I-17, I-10
(Maricopa Freeway) and US 60 (Superstition
Freeway), and SR 202L (Red Mountain Freeway)
and SR 101L (Pima Freeway).
➤➤ Operational
conditions in 2035 would be substantially
worse than those in 2010.
➤➤ In
2035, undesirable LOS would occur along both
directions of I-10, with few exceptions, for almost
30 miles between SR 101L (Agua Fria Freeway)
and SR 202L (Santan Freeway). Large portions of
the segment would experience LOS E or F for over
3 hours. In 2010, the congestion was mostly in the
peak direction and for a shorter duration.
➤➤ Alternative
routes to I-10 for eastbound travel,
including SR 202L (Red Mountain Freeway)
and SR 101L (Pima and Price freeways), would
experience LOS E or F in 2035.
➤➤ Based
on the projected duration of congested
conditions in 2035, travelers using the I-10 corridor
would experience substantial regional mobility
constraints. Even with RTP-planned major
transportation improvements to I-10 and construction
of the planned SR 30 freeway, motorists would
experience LOS E or F conditions for almost the
entire peak evening commuting period.
Capacity Deficiency of Existing
and Future Conditions
As presented in the previous sections, the region’s freeways
and arterial street network will continue to be heavily
congested; in fact, congested conditions will worsen.
Another way to illustrate travel demand is through use of
a cut-line analysis. A cut line is an imaginary line used to
represent the total traffic on freeways and arterial streets
that cross (or would cross) this given line. A cut-line
analysis is used to determine both the existing and future
distribution of traffic on the freeway and arterial street
networks. Six cut lines were identified through the Study
Area to assess changes in total traffic on arterial streets
and freeways between 2010 and 2035. In the analysis,
the 2035 road network included planned improvements
from the RTP (excluding the proposed action) and other
planned improvements from local, county, and private
agencies. Figure 1-11 presents the cut-line analysis.
Overall, ADT volumes through the six cut lines
displayed an increase of approximately 1.16 million
vehicles (684,000 on freeways and 474,000 on arterial
streets), or a 36 percent increase between 2010 and 2035.
Data from the cut-line analysis presented in Figure 1-11
were used to calculate the capacity deficiency of the
MAG region’s road network in 2010 and 2035, assuming
the network were to operate at LOS D during the peak
hour of a given day. Capacity deficiency was calculated
by comparing the total capacity and the total demand
of all of the roads that would cross the 41st Street cut
line (see Figure 1-11). Data are extrapolated from the
41st Street cut-line analysis to characterize performance
for the entire MAG transportation system. According to
the assessment (see Figure 1-12), the 2010 road network
was able to serve 81 percent of the total demand while
operating at LOS D. In 2035, however, the network
would be able to serve only 76 percent of the total demand
while operating at LOS D.
Between 2010 and 2035, RTP-planned major
transportation improvements outside of the Study Area
are to be constructed, adding additional capacity across
the 41st Street cut line. Even with these improvements,
travel demand will outpace the added capacity provided
by RTP-planned improvements, resulting in an increase
in unmet demand between 2010 and 2035.
Travel Time in the Study Area
and Immediate Surroundings
In the Study Area, increased traffic congestion has resulted
in decreased travel speeds throughout much of any given
day on the region’s road network. The amount of time
a driver spends driving each day to and from the same
origin and destination continues to increase. Travel time is
South Mountain Freeway (Loop 202) DEIS and Section 4(f) Evaluation
Chapter 1
•
Purpose and Need
1-17
Figure 1-9 Duration of Level of Service E or F, Morning Commute on Freeways, 2010 and 2035
Morning commute 2035
Study Area
Proposed freeway (RTPa)
SCOTTSDALE
Black Canyon
17 Freeway
Existing freeway
GLENDALE
Gila River Indian Community boundary
LOOP
101
Maricopa County line
51
PHOENIX
greater than 3 hours
less than 2 hours
AVONDALE
143
5 miles
30
Morning commute 2010
LOOP
101
PARADISE
VALLEY
GLENDALE
Agua Fria
Freeway
Location C
LOOP
Phoenix Sky Harbor
International Airport
Papago
60 Superstition
Freeway
GILBERT
Pima
Freeway
Location B
Phoenix South
Mountain Park/Preserve
10 Freeway
202
Ray Road
Red Mountain
Freeway
LOOP
Location A
Price
Freeway
LOOP
Maricopa
10 Freeway
143
101
202
DOWNTOWN
PHOENIX
TOLLESON
TEMPE
Gila River
Indian Community
PHOENIX
AVONDALE
To be named
Baseline Road
Piestewa
Freeway
51
Hohokam
Freeway
Broadway Curve
SCOTTSDALE
Black Canyon
Red Mountain
Freeway
MESA
Note: Segments without a color operate at LOS D or better during the morning commute.
17 Freeway
LOOP
202
DOWNTOWN
PHOENIX
TOLLESON
Approximate scale
1
Phoenix Sky Harbor
International Airport
Papago
10 Freeway
from 2 to 3 hours
LOOP
Pima
Freeway
PARADISE
VALLEY
Piestewa
Freeway
Agua Fria
Freeway
Duration of LOSb E or F
101
LOOP
101
Santan
Freeway
CHANDLER
Hohokam
Freeway
MESA
Location C
60 Superstition
Freeway
TEMPE
Broadway Curve
Baseline Road
Location B
Gila River
Indian Community
Phoenix South
Mountain Park/Preserve
Ray Road
LOOP
101
Location A
Price
Freeway
LOOP
202
Maricopa
Regional Transportation Plan
b
level of service
c
Interstate 10
d
U.S. Route 60
e
State Route 101L (Loop 101)
Santan
Freeway
During the morning commute, the region’s freeways are congested, most noticeably for motorists inbound to Phoenix.
Even though many improvements to the region’s transportation network are planned to address this congestion (exclusive
of the proposed action), it would become more severe. This is most noticeable at the following locations in the graphics:
Location A: I-10c (Maricopa Freeway) from Ray Road to Baseline Road would have segments with over 3 hours of
congestion in 2035 that were experiencing 2 to 3 hours or less than 2 hours of congestion in 2010.
Location B: US 60d (Superstition Freeway) heading west from SR 101Le (Price Freeway) to I-10 (Maricopa Freeway)
would have more segments with over 3 hours or 2 to 3 hours of congestion in 2035 when compared
with 2010.
Location C: The parallel routes of I-10 (Maricopa Freeway) and SR 202Lf (Red Mountain Freeway) east of downtown
Phoenix would have more segments with congestion and longer durations of congestion in 2035 than
in 2010.
CHANDLER
10 Freeway
a
1
f
State Route 202L (Loop 202)
Source: Maricopa Association of Governments, 2010b; extrapolated analysis
1-18
Chapter 1
•
Purpose and Need
South Mountain Freeway (Loop 202) DEIS and Section 4(f) Evaluation
Figure 1-10 Duration of Level of Service E or F, Evening Commute on Freeways, 2010 and 2035
1
Evening commute 2035
Study Area
Proposed freeway (RTPa)
Black Canyon
17 Freeway
51
Existing freeway
Gila River Indian Community boundary
Piestewa
Freeway
PARADISE
VALLEY
GLENDALE
Maricopa County line
Duration of LOS E or F
LOOP
101
101
PHOENIX
Agua Fria
Freeway
greater than 3 hours
Phoenix Sky Harbor
International Airport
Papago
10 Freeway
from 2 to 3 hours
less than 2 hours
AVONDALE
Approximate scale
143
30
Black Canyon
17 Freeway
LOOP
202
To be named
Location C
MESA
Hohokam
Freeway
60 Superstition
Freeway
TEMPE
Broadway Curve
GLENDALE
51
Agua Fria
Freeway
Location B
Piestewa
Freeway
PARADISE
VALLEY
PHOENIX
LOOP
101
Gila River
Indian Community
Pima
Freeway
Phoenix South
Mountain Park/Preserve
SCOTTSDALE
LOOP
101
Phoenix Sky Harbor
International Airport
Papago
10 Freeway
AVONDALE
GOODYEAR
TOLLESON
LOOP
202
Red Mountain
Freeway
Maricopa
Hohokam
Freeway
60 Superstition
Freeway
Broadway Curve
Location B
Gila River
Indian Community
Maricopa
10 Freeway
Phoenix South
Mountain Park/Preserve
LOOP
101
Price
Freeway
LOOP
202
Santan
Freeway
CHANDLER
Regional Transportation Plan
b
level of service
c
Interstate 10
d
Interstate 17
e
U.S. Route 60
f
Santan
Freeway
CHANDLER
MESA
TEMPE
Location C
a
LOOP
10 Freeway
143
Price
Freeway
202
DOWNTOWN
PHOENIX
Location A
Red Mountain
Freeway
DOWNTOWN
PHOENIX
5 miles
Evening commute 2010
101
Location A
TOLLESON
Note: Segments without a color operate at LOS D or better during the evening commute.
LOOP
Pima
Freeway
LOOP
b
1
SCOTTSDALE
State Route 101L (Loop 101)
g
The amount and duration of congestion are greater during the evening commute when compared with the morning
commute (see Figure 1-9). Conditions would substantially worsen by 2035, with much of the freeway network
congested in the evening for more than 2 hours. Also, during the evening commute, the congestion would occur in both
directions of travel, not just departing downtown Phoenix. These observations are most noticeable at the following
locations in the graphics:
Location A: I-10c (Papago Freeway) west of I-17d would have congestion for longer durations and extending farther
west as well as additional congestion in the eastbound direction in 2035 when compared with 2010.
Location B: US 60e (Superstition Freeway) heading east from I-10 (Maricopa Freeway) to SR 101Lf (Price Freeway)
would be entirely congested for over 3 hours in 2035 as compared with predominantly less than 2 hours
in 2010.
Location C: The parallel routes of I-10 (Maricopa Freeway) and SR 202Lg (Red Mountain Freeway) east of
downtown Phoenix would have more segments with congestion and longer durations of congestion
in 2035 than in 2010.
State Route 202L (Loop 202)
Source: Maricopa Association of Governments, 2010b; extrapolated analysis
South Mountain Freeway (Loop 202) DEIS and Section 4(f) Evaluation
•
LOOP
Piestewa
Freeway
48th Street
40th Street
101
32nd Street
16th Street
7th Street
7th Avenue
19th Avenue
27th Avenue
35th Avenue
43rd Avenue
Papago
51st Avenue
59th Avenue
67th Avenue
91st Avenue
75th Avenue
51
24th Street
Agua Fria
Freeway
83rd Avenue
LOOP
101
Travel times to and from specific locations were
calculated using the results from the TransCAD model,
which predicts average speed based on the road type and
LOS. Two trip locations were identified as representative
of travel times occurring in the Phoenix metropolitan
area, particularly in the urbanized and urbanizing areas
of the region. The two trips shown in Figure 1-13 are
representative of the expected increase in travel time
between 2010 and 2035. They do not represent every
trip taken within and around the Study Area, but give
an indication of potential impacts on future travel time.
Notable observations from the information are:
1
Pima
Freeway
Study Area
Proposed freeway (RTPa)
Existing freeway
Gila River Indian
Community boundary
Maricopa County line
Thomas Road
10 Freeway
Phoenix
Sky Harbor
International
Airport
Van Buren Street
Black Canyon
17 Freeway
143
Hohokam
Freeway
LOOP
Buckeye Road
202
E
UT-LIN
30
1
Cut lines
2
Southern Avenue
4
5
6
3
60 Superstition
Freeway
4
Baseline Road
3
5
Dobbins Road
time of 22 minutes for the morning commute
in 2010 for Trip 1 would increase to 31 minutes
in 2035; travel time of 23 minutes in the evening
would increase to 32 minutes in 2035.
Gila River
Indian Community
la
rel
t
Es
time of 17 minutes for the morning commute
in 2010 for Trip 2 would increase to 31 minutes
in 2035; travel time of 19 minutes in the evening
would increase to 32 minutes in 2035.
ive
Dr
87th Avenue
Salt River
South Mountain
47th Avenue
12th Street
41st Street
1
Broadway Road
IVER C
SALT R
To be named
Red Mountain
Freeway
Lower Buckeye Road
2
➤➤ Travel
6
Elliot Road
Phoenix South
Mountain Park/Preserve
Approximate scale
Warner Road
➤➤ Travel
1
5 miles
Ray Road
Maricopa
LOOP
101
10 Freeway
LOOP
202
Pecos Road
When considered in the context of hundreds of thousands
of trips per day, over the course of more than 25 years,
total time lost because of increased congestion—
plus related personal and financial costs—would be
substantial.
Cut line
Based on the assessment of existing and projected traffic
volume, LOS, capacity deficiency, and travel time, the
following conclusions are reached:
➤➤ Traffic
1
87th Avenue: I-10b (Papago Freeway) to Baseline Road
2
Salt River: 99th Avenue to SR 143c (Hohokam Expressway)
3
South Mountain: 83rd Avenue to I-10 (Maricopa Freeway)
4
47th Avenue: I-10 (Papago Freeway) to Estrella Drive
5
12th Street: I-10 (Papago Freeway) to Pecos Road
6
41st Street: SR 202Ld (Red Mountain Freeway) to Pecos Road
All six cut lines
a
Regional Transportation Plan
b
Interstate 10
c
State Route 143
d
State Route 202L (Loop 202)
Year
Total
2010
2035
2010
2035
2010
2035
2010
2035
2010
2035
2010
2035
2010
2035
301
464
669
1,001
314
458
392
530
729
898
798
1,001
3,194
4,352
Price
Freeway
Santan
Freeway
Volume (000s)
Major Points Regarding Projected Traffic
Volume, Level of Service, Capacity
Deficiency, and Travel Time
volume
➣➣ Between 2010 and 2035, total daily VMT in the
entire MAG region are projected to nearly double,
from 101 million to 185 million. Daily VMT
in the Study Area are projected to increase
substantially during the same period.
1-19
Purpose and Need
Figure 1-11 Cut-line Analysis, 2010 and 2035
99th Avenue
important to most drivers; further, increases in travel time
translate to more congestion. It is important, therefore, to
examine representative travel times in different locations
and project what travel times would be in 2035.
Chapter 1
Split (%)
Freeways Arterials Freeways Arterials
232
366
438
654
239
307
265
287
508
612
489
629
2,171
2,855
69
98
231
347
75
151
127
243
221
286
300
372
1,023
1,497
77
79
65
65
76
67
68
54
70
68
62
63
68
66
23
21
35
35
24
33
32
46
30
32
38
37
32
34
Source: Maricopa Association of Governments, 2010b; extrapolated analysis
The volume of traffic on local arterial streets would increase at a greater rate than would the volume on freeways. Therefore, a desired outcome of the Regional Transportation Plan—
to redistribute traffic appropriately based on travel needs—would not be achieved in the Study Area and its immediate surroundings without a new major transportation facility constructed
in the Study Area.
1-20
Chapter 1
•
Purpose and Need
South Mountain Freeway (Loop 202) DEIS and Section 4(f) Evaluation
volumes on freeways and arterial streets in
the Study Area and its immediate surroundings
are projected to increase substantially
between 2010 and 2035.
1
19%
81%
➤➤ LOS
2010
➣➣ During
24%
76%
2035a
0
20
Percentage of systemwide demandb
of existing travel demand. Even with the major
transportation improvements planned in the RTP
(except for the proposed action), the 2035 system
would be able to meet only 76 percent of projected
travel demand.
➣➣ Traffic
Figure 1-12 Met and Unmet Demand, 2010 and 2035
40
60
80
100
Met demand c
Unmet demandd
Source: Maricopa Association of Governments, 2010b; extrapolated analysis
a
The analysis assumes that the Maricopa Association of Governments (MAG) Regional Transportation Plan is fully
implemented in 2035 (except for any major transportation facility in the Study Area).
b
Data are extrapolated from the 41st Street cut-line analysis (see text and Figure 1‑11) to characterize performance for the
entire MAG transportation system.
c
T he demand met by the region’s transportation system.
d
Unmet demand means delays and congestion for travelers on the MAG transportation network.
the morning and evening commutes
in 2010, the region’s freeways were noticeably
congested and operated poorly.
➣➣ Even with RTP-planned improvements
(without the proposed action), congestion
conditions in 2035 would be worse than
those in 2010.
➤➤ Travel
time
➣➣ Trips between locations in the Study Area and
downtown Phoenix would take much longer
in 2035 than they did in 2010; the projected
travel time would increase by between 39 and
82 percent.
Based on the consideration of existing traffic conditions
in the MAG region and the Study Area, the need for
a major transportation facility in the Study Area exists
today. Based on projections of 2035 traffic conditions, the
need for such a facility will be even greater in the future.
➤➤ Capacity
deficiency
➣➣ The transportation system will continue to be
unable to meet regional travel demand.
➣➣ In 2010, the regional transportation system’s
operating capacity was able to meet 81 percent
Even with improvements planned in the Regional Transportation Plan (excluding the proposed action), capacity
deficiency (unmet demand) is projected to increase by 5 percentage points from 2010 to 2035.
Figure 1-13 Modeled Travel Times without the Proposed Action, 2010 and 2035
LOOP
Existing freeway
les Agua Fria
nge 101 Freeway
Indian School Road Los A
Gila River
To
Indian Community
Papago
boundary
10 Freeway
Maricopa County
TOLLESON
line
Lower Buckeye Road
Morning travel
BUCKEYE
Evening travel
Black Canyon
17 Freeway
LOOP
Trip 1
51
Piestewa
Freeway
PHOENIX
LOOP
101
Piestewa
Freeway
PHOENIX
TEMPE
McDowell Road
APACHE
McKellips
Road
JUNCTION
Brown Road
University Drive
Price
101 Freeway
Travel time, 2010
morning = 17 minutes
evening = 19 minutes
GILBERT
Phoenix South
Mountain Park/Preserve
Travel time, 2035
morning = 31 minutes
evening = 32 minutes
Maricopa
10 Freeway
I-10/SR 202L
(Santan)/Pecos Road
interchange
Santan
Maricopa
Ray Road
Williams Field Road
LOOP
n
n
cso
Tu
To
CHANDLER
5 miles
so
so
1
Gila River
Indian Community
Warner Road
10 Freeway
c
Tu
To
c
Tu
To
Approximate scale
Sierra Estrella
Mountains
Baseline Road
Guadalupe Road
LOOP Price
101 Freeway
Elliot Road
202
202 Freeway
Gila River
Indian Community
Broadway Road
Southern Avenue
I-10/Washington Street
interchange
Trip 2
LOOP
TEMPE
60 Superstition
Freeway
LOOP
5 miles
LOOP
143 Hohokam
Freeway
Approximate scale
1
Phoenix Sky Harbor
Pima
Thomas Road
International Airport 101 Freeway
MESA
TOLLESON
51st Avenue/Elliot Road
intersection
Date _______________
Chaparral Road
Indian School Road
Papago
I-10/7th Avenue
interchange
Phoenix South
Mountain Park/Preserve
McDonald Road
51
10 Freeway
Signature __________
Sierra Estrella
Mountains
Black Canyon
17 Freeway
Phoenix Sky Harbor
International Airport 101 Pima
Freeway
AVONDALE
Travel time, 2035
morning = 31 minutes
Master Base
evening = 32 minutes
Agua Fria
Freeway
LOOP
GOODYEAR
Travel time, 2010
morning = 22 minutes
evening = 23 minutes
Figure #:
Red Mountain
202 Freeway
Bethany Home Road
Santan
Freeway
Williams Gateway
FreewayGermann Road
Queen Creek Road
Ocotillo Road
Chandler Heights Road
Source: Maricopa Association of Governments, 2010b; extrapolated analysis
Riggs Road
n
The changes in travel time represent what can be expected throughout the Maricopa Association of Governments region. When considered in the context of hundreds of thousands of trips per day,
over the course of more than 25 years, total time lost because of increased congestion—plus related personal and financial costs—would be substantial.
South Mountain Freeway (Loop 202) DEIS and Section 4(f) Evaluation
Chapter 1
•
Purpose and Need
1-21
CONCLUSIONS
The information in this chapter shows that without
a major transportation facility in the Study Area,
the region’s transportation network will suffer. As
recognized in over 25 years of transportation planning,
the region’s transportation network will not be able to
efficiently move goods and people throughout the region
without major investments in the network. Projected
growth in population, housing, and employment will
force motorists to drive longer distances and will push
more traffic onto regional freeways and arterial streets,
especially within the Study Area. These increases in the
number of vehicles and in longer-distance drives will
cause increased congestion. In extreme cases, drivers
could experience their afternoon commute extending
well into precious evening hours. In all cases, stopand-go traffic on the region’s freeways and arterial
streets would increase and delays in getting to and from
destinations would result. Correspondingly, productivity
would decline.
Major points establishing the need for a major
transportation facility are:
➤➤ Regional
plans have recognized the need for
completing the loop system around the Phoenix
metropolitan area for over 25 years. The Southwest
Loop Highway, a major element of the region’s
freeway loop, or beltway, system was integral to the
Regional Freeway and Highway System approved
by Maricopa County voters in 1985. In 1988, this
plan was carried forward as a State-level EA and
DCR for the Southwest Loop Highway (now
known as the South Mountain Freeway). The same
route was approved by the STB in the same year.
Although other facilities were considered a higher
priority early in the Regional Freeway and Highway
System, the South Mountain Freeway was a part
of the initial Regional Freeway and Highway
System in 1985 and has been included in every
subsequent update. In 2004, Maricopa County voters
approved Proposition 400, which was designed
to fund completion of the remaining segments
of the Regional Freeway and Highway System,
including the South Mountain Freeway. A major
transportation facility in the Study Area would
implement the facility recognized in over 25 years of
planning.
➤➤ Since
the 1950s, the MAG region has experienced
rapid growth in population, housing, and
employment, and this growth is expected to
continue. Between 2005 and 2035, Maricopa County
is projected to experience an increase in population,
going from 3.7 million to 6.5 million, and in the
number of housing units, going from 1.5 million to
2.7 million. Regional employment is projected to
double, going from 1.7 million to 3.6 million jobs
during the same period. Because of the substantial
increase in population, homes, and jobs, people
will drive greater distances for work, school, and
recreation. As a result, VMT are expected to
increase even faster than population, housing, and
employment. A major transportation facility in the
Study Area is needed to accommodate or displace
the ever-increasing VMT.
➤➤ MAG
projects that over the next 25 years, daily
VMT in the entire MAG region will increase from
101 million to 185 million. Over that same period,
MAG anticipates that daily VMT in the Study Area
will increase at a similar high rate, from 27 million
to 42 million. The increased VMT will mean more
traffic on regional freeways and arterial streets.
This increased transportation demand must be met;
otherwise, the available lanes on the region’s roads
will be at capacity, causing an unacceptable degree
of congestion. A major transportation facility in the
Study Area would provide an additional method
of serving this increased transportation demand
by removing traffic from existing freeways and
arterial streets, resulting in better traffic flow on
surface transportation networks of all types. All
surface transportation systems in the MAG region
were designed to function optimally only with
implementation of a major transportation facility in
the Study Area.
➤➤ Providing
a major transportation facility in an
area where it would not be fully used would be an
unwise expenditure of public funds. Of the projected
76 percent increase in population, 80 percent
increase in housing units, and 112 percent increase
in jobs between 2005 and 2035, nearly half of
these increases are expected in areas that would be
immediately served by the proposed action. A major
transportation facility in the Study Area would
provide highly needed services precisely where they
will be needed.
➤➤ Without
a major transportation facility in the Study
Area, the increased VMT described previously will
cause systemwide inefficiencies in the ability to
move people and goods and will result in suboptimal
performance characteristics on other RTP facilities,
both existing and planned:
➣➣ Even though the region’s freeways are now
congested and operate poorly, conditions in 2035
would be substantially worse. Although some
areas of severe congestion currently exist, they are
limited (e.g., eastbound I-10 [Papago Freeway]
approaching I-17 and eastbound and westbound
I-10 [Maricopa Freeway] at the Broadway Curve).
By 2035, eastbound and westbound motorists
on I-10 between SR 101L (Agua Fria Freeway)
and SR 202L (Santan Freeway) are expected to
experience stop-and-go driving for over 3 hours
every day. This is a distance of nearly 30 miles. A
major transportation facility in the Study Area
would distribute commuters over additional
facilities. As a result, the duration of stop-and-go
traffic on the region’s freeways would be reduced
and motorists would spend less time in the
morning trying to get to work or appointments
and less time in the evening trying to get home
from work.
➣➣ Congestion in 2035 will not be limited to regional
freeways. In the Study Area, an increase in daily
traffic volumes of approximately 32 percent on
1
1-22
1
Chapter 1
•
Purpose and Need
freeways and 46 percent on arterial streets is
projected between 2010 and 2035. Therefore, in
addition to the stop-and-go traffic on freeways,
these conditions would be replicated on arterial
streets—and compounded by traffic signals. This
46 percent increase in daily traffic on arterial
streets correlates to a need for 55 additional lanes
of arterial street capacity in the Study Area.
Constructing an additional 55 street-lanes would
not likely occur because of the right-of-way
(R/W) that would be needed and accompanying
impacts on existing residential and commercial
properties. A major transportation facility in the
Study Area would provide an additional means
to serve this increased transportation demand by
removing traffic from arterial streets, which would
result in better traffic flows and less congestion on
arterial streets.
➣➣ Another way of looking at the negative effects
of the projected increase in VMT is the delays
experienced by the daily commuter. Increased
traffic congestion would extend the amount
of time spent driving to and from the same
origin (home) and destination (work or school).
According to transportation analyses, depending
on location and time of trip, increases of up
to 88 percent in the time needed to complete
the same trip would be expected between 2010
South Mountain Freeway (Loop 202) DEIS and Section 4(f) Evaluation
and 2035. It is important to note that this is
a single trip. Considering the hundreds of
thousands of drivers on area roads each day, the
total lost time and associated cost of increased
congestion would be substantial over the course of
more than 25 years. A major transportation facility
in the Study Area would distribute commuters
over additional facilities. As a result, delays
experienced on the region’s freeways and arterial
streets would be reduced and commuters could
spend the time savings in more productive and/or
enjoyable endeavors than sitting in congestion on
regional freeways and roads.
Population, housing, and employment forecasts for the
Study Area and Phoenix metropolitan region show
tremendous growth in the region during the next
25 years. This includes a population increase of 2.8 million
people, a housing increase of 1.2 million units, and an
employment increase of 1.9 million jobs. This projected
growth will affect not only the freeway system but will
also cause many of the arterial streets in the Study Area to
experience additional congestion and traffic backups onto
the existing freeways, worsening travel conditions on an
already-burdened transportation system.
In 2010, the region’s freeways were congested and
operated poorly, but conditions in 2035 would be
substantially worse than the limited areas of stop-and-go
driving experienced in 2010. By 2035, eastbound and
westbound motorists on I-10 between SR 101L (Agua Fria
Freeway) and SR 202L (Santan Freeway) will experience
stop-and-go driving for at least 3 hours every day.
Today’s freeways and arterial streets will not operate
efficiently with the population, housing, and
employment increases forecast for 2035. Combined, these
increases will translate into higher demand for use of
the existing freeway and arterial street systems. In 2010,
the existing road network could serve only 81 percent
(34,400 of 42,500 trips during the peak hour) of the
total demand on the transportation system. During the
next 25 years, daily traffic volumes in the Study Area
are expected to increase by approximately 36 percent
(from 3.19 million to 4.35 million daily trips) on freeways
and arterial streets. Individually, the 684,000 trip
increase on freeways would equate to the capacity of
26 freeway lanes, and the 474,000 trip increase on
arterial streets would equate to the capacity of 55 arterial
street lanes. By 2035, without the proposed action, the
network will be able to accommodate only 76 percent
(40,700 of 53,900 trips during the peak hour) of total
transportation needs. Without a major transportation
facility in the Study Area, the region will suffer even
greater congestion, travel delays, and limited options for
moving people and goods safely through the Phoenix
metropolitan region.