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FEASIBLE ALTERNATIVES RECOMMENDED FOR FURTHER STUDY
Five conceptual build alternatives were studied in Step 5 of ODOT’s Project Development Process:
- No Build Alternative: An alternative, which maintains the current four-lane configuration of I-75 and consists of minor, short-term safety and maintenance to the interstate, which would maintain its continuing operation.
- Alternative A: A four-lane alternative, which upgrades the existing I-75 mainline and interchange ramps to meet current geometric design standards (Alternative A).
- Alternative B: A four-lane alternative, which upgrades the existing I-75 mainline and interchange ramps to meet current geometric design standards and makes provisions for future upgrade to a six-lane facility (Conceptual Alternatives B and D).
- Alternative C: A four-lane alternative, which upgrades the existing I-75 mainline and interchange ramps to meet current geometric design standards, provides auxiliary lanes where necessary in areas of level of service D or worse, and provides for future upgrade to a six-lane facility.
- Alternative D: A six-lane alternative, which upgrades the existing I-75 mainline and interchange ramps to meet current geometric design standards (Conceptual Alternatives B and D).
A comparative analysis was conducted for the five conceptual build alternatives. The analysis focused on results of the traffic analysis, environmental consequences, and cost estimates (Summary of Impacts by Mainline Alternative). The analysis determined that Alternative A is the least expensive and has the least amount of environmental impacts of the conceptual build alternatives. The design features of Alternative A would improve pavement and bridge conditions, improve safety and provide LOS B and C in 2035 within the I-75 corridor. In addition to the design features develop in Step 5 for Alternative A, the overpass structures will be constructed to provide for a future third lane in each direction on I-75 since the expected life for structures is 50 years versus the 20 years identified for design.
Based on construction and right of way cost estimates, environmental impacts, levels of service, and engineering design features, Alternative A is recommended as the feasible alternative to be developed in further detail in Step 6 of the Project Development Process. The No Build Alternative will be retained as a baseline for evaluation of Alternative A throughout the project development process.
Alternative A
Alternative A will reconstruct the existing pavement and be designed and built to current ODOT highway and bridge design and construction standards (Alternative A). The proposed typical section for Alternative A has two design scenarios (Alternative A Roadway Typical Sections). In the mainline sections with a grass median area, there would be four-foot inside shoulders, two 12-foot lanes, and a 12-foot outside shoulder. The mainline sections with a median barrier would have a 12-foot inside shoulder, two 12-foot lanes, and a 12-foot outside shoulder.
Design features of Alternative A, which will improve traffic flow, safety, and local connectivity include:
Interchange Reconstruction Options
Alternative A includes rehabilitation of all interchanges with the exception of SR 81, which will be reconstructed. Rehabilitation is the reconstruction and upgrade of an interchange to current state and federal design standards. The configuration of the interchange remains the same but the lanes and shoulders are widened and ramps are lengthened. The SR 81 interchange will not be rehabilitated because it is more cost efficient to reconstruct the interchange in a diamond design. A diamond interchange would also operate more efficiently than the current interchange design. Additional design options were analyzed at the other interchanges and recommended for elimination or further development. The one exception is the SR 65 interchange. Rehabilitation was the only option studied for this interchange. Click on the following links to see the options proposed at each of the five interchanges:
Breese Road Interchange
SR 65 Interchange
Fourth Street Interchange
SR 309/117 Interchange
SR 81
The interchange options recommended for further study in Step 6 of the Project Development Process are:
No Build Alternative
The No Build Alternative maintains the current four-lane configuration of I-75 and consists of minor, short-term safety and maintenance to the interstate, which would maintain its continuing operation. The No Build Alternative is retained as a baseline for evaluation of Alternative A.
The No Build Alternative would not meet the purpose and need for the Allen 75 Study or the project goals established by stakeholders. It would not improve pavement performance and roadway deficiencies. Current safety problems and geometric deficiencies of the roadway network would continue to exist and could possibly become worse over time as traffic volumes increase in the I-75 corridor. According to the traffic analysis, levels of service (LOS) along I-75 will decline in the future, as traffic volumes increase. Levels of service on I-75 and interchange ramps would be LOS B and C in 2015. The level of service on certain mainline segments and interchange ramps would decrease over time. In 2035, the level of service would be LOS C along the I-75 corridor with the exception of three locations:
- The Breese Road northbound mainline segment of I-75 would operate at LOS B (17.5 passenger cars / mile / lane) in the peak hour of year 2035.
- The on-ramp from SR 117 / 309 to northbound I-75 is expected to operate at LOS D (28.1 passenger cars / mile / lane) in the peak hour of year 2035.
- The off-ramp from I-75 northbound to SR 81 eastbound is expected to operate at LOS D (28.5 passenger cars / mile / lane) in the peak hour of year 2035.
Conceptual Alternatives B, C, and D
Conceptual Alternatives B, C, and D were developed and studied in Step 5 of the Project Development Process. Based on the comparative analysis for the five conceptual alternatives, Alternatives B, C, and D were eliminated from further consideration and will not be carried forward as feasible alternatives in the next steps of the project. The following is a summary of the comparative analysis and the reasons for eliminating Conceptual Alternatives B, C, and D.
Alternative B
Alternative B is a hybrid of Alternatives A and D therefore, it reflects elements of the two conceptual build alternatives. Alternative B is a four-lane alternative, which provides a right of way for six travel lanes, therefore, Alternatives B and D have the same proposed right of way limits and environmental impacts. The design features of Alternative B would improve pavement and bridge conditions, provide more room to accommodate future maintenance, improve safety and provide LOS B and C in 2035 within the I-75 corridor. The right of way cost for Alternative B is $18,557,634, which is the same as Alternative D and greater than Alternative A ($15,675,208). The preliminary construction cost for Alternative B is estimated to be $234,206,218. The estimated construction cost is lower than Alternative D ($246,522,804), but higher than Alternative A ($203,430,157). This is because the overpasses and other design features would be constructed to accommodate a third travel lane in the future. Based on the traffic analysis, a third future travel lane is not justified, LOS B and C can be achieved with four travel lanes in 2035. Because of the high costs and environmental impacts, Alternative B is not justified as a feasible alternative and is not recommended for further study.
Alternative C
Alternative C is a four-lane alternative, which upgrades the existing I-75 mainline and interchange ramps to meet current geometric design standards, provides auxiliary lanes where necessary in areas of level of service D or worse, and makes provisions for future upgrade to a six-lane facility. The traffic analysis determined that LOS B and C can be achieved from Alternative B by improving acceleration/deceleration lane lengths and distances between successive ramps. Therefore, Alternative C was determined not to be necessary and eliminated from further consideration.
Alternative D
Alternative D is the most expensive to construct of the three conceptual build alternatives, because it would provide six travel lanes on I-75. The six travel lanes would provide LOS A and B on the I-75 mainline and interchange ramps in 2035. The environmental impacts that would result from Alternative D are higher than Alternative A, because of the wider right of way needed to accommodate a six-lane highway. Alternative D is not recommended as a feasible alternative because of its environmental impacts and high construction cost $246,522,804. Alternatives A and B would satisfy the project goals for lower costs.
OVERVIEW OF THE CONCEPTUAL ALTERNATIVES DEVELOPMENT 2005 TO 2007
A broad range of conceptual alternative solutions was developed for the Allen 75 Study in 2005. These conceptual alternative solutions included ideas developed through stakeholder input. They ranged from no build, low-cost concepts to modal options and highway build concepts. These conceptual alternative solutions were:
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No Build
- Freight Rail
- Mass Transit
- Transportation Systems Management (TSM)
- Transportation Demand Management (TDM)
- Highway Build
The conceptual alternative solutions and their analysis are described in detail in the Conceptual Alternatives (October 2006) document.
HIGHWAY BUILD ALTERNATIVES
Six highway build conceptual alternative solutions were developed, which consisted of combinations of various roadway and interchange improvements.
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Conceptual alternative 1 was the No Build alternative, which maintains the current four-lane configuration of I-75. The No Build alternative consists of minor, short-term safety and maintenance improvements to I-75, which would maintain its continuing operation.
- Conceptual alternatives 2 and 3 proposed bypasses around the city of Lima.
- Conceptual alternative 4 maintained the current four-lane configuration of I-75 while adding improvements to bring I-75 up to current ODOT standards.
- Conceptual alternatives 5, 6, and 7 proposed six travel lanes on I-75, with different combinations of interchange and local roadway improvements.
The following table summarizes the components of each highway build conceptual alternative solution, along with possible options. The options were developed to better integrate I‑75 with the local traffic network, and to maximize the performance of the conceptual alternatives.
Components of the No Build and Highway Build Conceptual Alternatives 
Options
Optional improvements were developed for highway build conceptual alternatives 4, 5, 6 and 7 to enhance connectivity with the local traffic network and to maximize the performance of the concepts. Each of the four conceptual alternatives has a different set of options associated with it, as shown in the table above. The options improvements are described in detail in the Conceptual Alternatives (October 2006) document.
The conceptual alternative solutions developed for the Allen 75 Study were evaluated using a two-step screening process based upon a comparative analysis. The goal of this analysis was to identify conceptual alternative solutions for further study and development. Details of the comparative analysis are presented in the Conceptual Alternatives (October 2006) document.
Step one of the analysis evaluated the conceptual alternative solutions based on the purpose and need goals of the Allen 75 Study. The ability of each conceptual alternative to address the goals of the purpose and need was determined. The conceptual alternative solutions that best addressed these goals were carried forward into step two of the analysis, along with the No Build alternative.
In step two, the conceptual alternative solutions that were retained in step one were evaluated using stakeholders’ goals and measures of success; community economic strategic goals as presented in the Comprehensive Economic Development Strategy for Allen County, Ohio 2005; estimated environmental impacts; and preliminary construction costs.
As a result of the step one analysis, freight rail, mass transit, TDM, TSM, and highway build conceptual alternatives 2 and 3 were not forwarded for further study. Highway build conceptual alternatives 4, 5, 6, and 7 could meet the purpose and need goals and were carried forward to step two of the analysis. The No Build alternative was also retained as a baseline for evaluation of the highway build conceptual alternative solutions.
In the step two analysis, the No Build ranked lowest in terms of traffic level of service and economic development benefits, and scored highly on environmental impact and cost criteria. Conceptual alternative 4 ranked low on the traffic-related criteria, and performed similar to conceptual alternative 5 on the environmental criteria. Conceptual alternative 4 had the lowest cost of the highway build conceptual alternatives. Highway build conceptual alternatives 5, 6, and 7 ranked close to each other in step two of the analysis, with conceptual alternative 5 predicted to have the fewest environmental impacts of any of the six-lane alternatives.
The step two analysis did not identify any fatal flaws for conceptual alternatives 4, 5, 6, or 7, which would eliminate them from further study. Therefore, it was recommended that conceptual alternatives 4, 5, 6, and 7 be carried forward for further study in the next steps of the project development process, along with their associated options. The No Build alternative was also carried forward to serve as a baseline against which the costs and benefits of the highway build conceptual alternative solutions could be assessed.
In Summary
Conceptual Alternative 4 maintained SR 117 in its current configuration, and I-75 is rebuilt as a four-lane facility with all interchanges in their current locations. The I 75 mainline and all overpass bridges and the five interchanges between and including Breese Road and SR 81 would be rebuilt to meet current ODOT design standards. Conceptual Alternative 4 Exhibit
The three recommended six-lane conceptual alternatives differed primarily in the realignment of SR 117 as it enters Lima from the east.
Conceptual Alternative 5 maintained SR 117 in its current configuration. The I-75 mainline would be rebuilt as a six-lane facility, and the five interchanges between and including Breese Road and SR 81 would be rebuilt in their existing locations. Conceptual Alternative 5 Exhibit
Conceptual Alternative 6 proposed realigning SR 117 on a new road to be constructed along the abandoned railroad corridor south of SR 309. As part of this conceptual alternative, the interchanges at SR 309 and at Fourth Street would be removed, to be replaced with a new interchange at the relocated SR 117. Greely Chapel Road, which parallels I-75 approximately ¼-mile east of the interstate would be improved to provide access to the new interchange. Access on the west side of I 75 would be provided by a new service road. The I 75 mainline would be rebuilt as a six-lane facility, and the interchanges at Breese Road, SR 65 and SR 81 would be rebuilt in their existing locations. Conceptual Alternative 6 Exhibit
Conceptual Alternative 7 proposed realigning SR 117 to follow Fourth Street. Fourth Street would extend east of Bowman Road on new alignment to meet existing SR 117. Existing Fourth Street would be improved but not widened between SR 65 and Bowman Road. SR 117 traffic would enter I 75 via the Fourth Street interchange, reducing traffic volumes and the potential for vehicular conflicts at the existing SR 309/117 interchange area. The I 75 mainline would be rebuilt as a six-lane facility, and the five interchanges between and including Breese Road and SR 81 would be rebuilt in their existing locations. Conceptual Alternative 7 Exhibit
Interchange Conceptual Alternatives and Options
Conceptual interchange alternatives were developed for six interchanges on I-75 in 2006. Each of the conceptual alternatives includes local road improvement options that could be constructed. The conceptual interchange alternatives were presented to project stakeholders on December 19, 2006.
Exhibits of the conceptual interchange alternatives and options are available for review:
CONTINUING DEVELOPMENT OF THE CONCEPTUAL ALTERNATIVES
The Allen 75 Study moved forward into Step 5 of ODOT’s Project Development Process in 2007. Conceptual alternatives 4, 5, 6, and 7 and the conceptual interchanges were further developed and studied in more detail in Step 5. As a result of the traffic, environmental, and engineering studies; and stakeholder coordination Conceptual alternatives 4, 5, 6, and 7 evolved into two design scenarios, a four-lane and a six-lane alternative. The conceptual interchange alternatives and options also changed as design elements were combined and/or eliminated. Conceptual alternative 4 became the four-lane alternative and conceptual alternatives 5, 6, and 7 were combined into a six-lane alternative. As a result, five conceptual build alternatives were studied in Step 5 of the Project Development Process:
- No Build Alternative: An alternative, which maintains the current four-lane configuration of I-75 and consists of minor, short-term safety and maintenance to the interstate, which would maintain its continuing operation.
- Alternative A: A four-lane alternative, which upgrades the existing I-75 mainline and interchange ramps to meet current geometric design standards.
- Alternative B: A four-lane alternative, which upgrades the existing I-75 mainline and interchange ramps to meet current geometric design standards and makes provisions for future upgrade to a six-lane facility.
- Alternative C: A four-lane alternative, which upgrades the existing I-75 mainline and interchange ramps to meet current geometric design standards, provides auxiliary lanes where necessary in areas of level of service D or worse, and provides for future upgrade to a six-lane facility.
- Alternative D: A six-lane alternative, which upgrades the existing I-75 mainline and interchange ramps to meet current geometric design standards.
Alternatives A, B, C, and D also included upgrading the interchanges at Breese Road, SR 65, Fourth Street, SR 309/117 and SR 81 to meet current design standards. A new interchange located on the railroad corridor between Fourth Street and SR 309/117 was studied. These conceptual build alternatives and interchange design options were presented to stakeholders and the public on May 6, 2008. |
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