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I-64 Draft Environmental Impact Statement

II-1





CHAPTER II
Alternatives

This chapter presents the definition of the alternatives considered for improvements on I-64
from west of Spoede Road in St. Louis County to west of Sarah Street in the city of St. Louis,
and on I-170 from south of Brentwood Boulevard to Eager Road. This chapter includes: (1) a
discussion of the development of the initial improvement concepts, (2) the development of a
methodology to evaluate those concepts, and (3) the evaluation of the defined set of
alternatives that were carried forward for more detailed evaluation as part of this environmental
impact statement.

The process to develop and evaluate potential improvements that address the purpose and
need for the project is described in this chapter. The process began with the development of a
large number of improvement concepts. The initial improvement concepts included the
consideration of all modes of transportation. It was determined that none of the travel modes
individually would address all of the transportation needs within the I-64 Corridor. For that
reason, both transit and highway improvements are being pursued. Transit concepts are being
further developed by Bi-State Development Agency. Highway improvements and specifically
improvements to I-64 are the subject of this EIS.

The highway improvement concepts include both mainline concepts and interchange options.
These initial concepts were first evaluated at individual locations. In the second step of the
process, those interchange and mainline concepts that addressed the project purpose and need
were then combined to create corridor-wide alternatives. As engineering review and refinement
was completed, a number of the concepts were refined or eliminated from further consideration.
In the third analysis phase, a set of reasonable project alternatives were evaluated in greater
detail. This process is illustrated in Figure II-1 below and described in detail in the following
sections of this chapter.

Figure II-1
Process to Develop Alternatives

Complete Engineering Refinements
and Finalize Set of Reasonable
Alternatives
Produce Conceptual Engineering
Plans and Evaluate Set of
Reasonable Alternatives
Develop Improvement Concepts
Mainline
Concepts
Interchange
Options II-2
The New I-64

Draft Environmental Impact Statement



A considerable amount of public involvement was conducted during the formulation and
evaluation of potential improvements. Three corridor subcommittees were formed and used to
provide input into the evaluation process. A subcommittee was formed for each of the
subcorridors: the Greenway, the Thruway and the Parkway. Participants in these
subcommittees were representatives of individual neighborhood associations, representatives of
local governments or individual citizens. In addition, region-wide public meetings were also
held. More details on the public involvement process and the function of the subcommittees
can be found in Chapter VIII Comments and Coordination.

A. Improvement
Concepts

Conceptual design for improvement of the existing I-64 facility was completed to formulate
specific mainline and interchange design options. The initial Build Concepts were developed
based on general guidelines. The guidelines support the purpose and need of the project with
specific attention given to improving design criteria and minimizing the need for additional right-
of-way (R/W). These guidelines included:

Physical Constraints As directed by input from adjacent communities and the project
subcommittees, due to the tight R/W constraints along I-64 and I-170, options were
developed that require less area and minimize impacts to existing land uses.

General Design Criteria Build Concepts followed the American Association of State
Highway and Transportation Officials (AASHTO) design criteria. The AASHTO design
criteria incorporate standards applicable to the Americans with Disabilities Act (ADA).

1. CONCEPT
DEFINITION

The following types of improvements have been considered:

a. No-Build
Concept

The No-Build Concept includes minor short-term activities, including pavement overlays, routine
maintenance and bridge repair. Many of the bridges in the I-64 Corridor are 60 years old or
more, and this concept would involve maintenance activities required to keep these bridges
open for as long of a period as possible.

b. Reconstruction
Concept

The existing I-64 roadway through the study corridor is generally a six-lane facility, with three
lanes of travel in each direction from Spoede Road to McCausland Avenue and an eight-lane
facility, with four lanes of travel in each direction, from McCausland Avenue to Sarah Street.
West of Spoede Road, I-64 has recently been reconstructed to eight lanes. Due to the existing
need or the need that will exist within the next 20 years to replace deteriorated pavement and
bridges, the Reconstruction Concept assumes reconstruction of the pavement and
replacement or rehabilitation of bridges that are structurally deficient. The Reconstruction
Concept includes only minor changes or modifications to the existing configuration of the I-64
and the I-170 mainline and to the configuration of interchanges on I-64 and I-170. In addition,
the Reconstruction Concept would not bring the roadway within the study corridor up to
Missouri Department of Transportation (MoDOT) and Federal Highway Administration (FHWA)
recommended standards and policies for reconstructed urban freeways.

c.
Transportation System Management (TSM) /
Travel Demand Management (TDM) Concept

Transportation System Management (TSM) improvements are low cost system enhancements
that improve the transportation system efficiency. TSM includes the use of a wide range of CHAPTER II Alternatives Considered
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strategies aimed at making more efficient use of existing transportation facilities. Listed below
are possible TSM improvements:

Minor Interchange Improvements include improvements to ramp merge and diverge
configurations and surface street intersection improvements. Improvements at ramp
terminal intersections with surface streets include constructing turn lanes, realigning
intersections and adding or improving existing traffic signal systems. These
improvements can be implemented within existing R/W.

Intelligent Transportation Systems (ITS) implement technology-based systems to
improve safety and more efficiently manage the transportation system. In the realm of
roadway operations, ITS focuses on smoothing traffic flow through enhanced traveler
information, minimizing the impact of incidents and regulating traffic flow. Traffic flow
can be managed through ramp metering and traveler information to allow motorists to
make informed travel decisions. Incident management strives to detect, respond,
manage and clear incidents that impact traffic flow. Devices used in freeway
management systems include traffic sensors, closed-circuit television cameras, variable
message signs (message boards), highway advisory radio, ramp metering, public safety
agency communication links, media communication and web pages.

Travel Demand Management (TDM) measures are designed to reduce congestion on
the existing transportation infrastructure by encouraging commuters and/or employers
to:

Vary the time and location of trips (flexible work hours)
Support ride sharing and car pooling
Support increased transit use

High Occupancy Vehicle (HOV) lanes


d.
Transit Concepts

Public transportation options and transit options within the I-64 corridor were evaluated as part
of the Cross County MTIA Study and the Daniel Boone MTIA Study, as discussed in Chapter I.
Interstate 64 could be used as a possible alignment for light rail transit either in the middle of the
highway or along one side within existing R/W. It was decided in these studies that west of I-
170 light rail transit would best be extended by utilizing existing or abandoned rail corridors
located north of the I-64 study corridor that serve the same travel market as I-64. The extension
of MetroLink (light rail transit) east of I-170 is currently being designed by Bi-State on an
alignment located north of Forest Park to the city of Clayton and then south paralleling I-170
crossing under I-64 and ending at I-44. During the MTIA studies, public involvement by others
including public hearings was extensive, and a summary is available by request to EWGCC.

The potential extension of MetroLink to the west of I-170 was evaluated. Based upon the
evaluation of an available corridor adjacent to I-64, and the R/W constraints within the I-64
c