Overview of Process to Determine, Present, and Select Feasible Alternatives
Initially, a range of alternatives are developed based upon past and ongoing alternatives and studies, stakeholder and public input/recommendations, agency input, and design standards. Once this range of alternatives are established, they are funneled through a 2 tiered screening process.
Tier 1 Screening
The Tier 1 Screening evaluates each alternative to determine if it meets the primary purpose and need as well as minimum design criteria. The alternatives that pass this screening will move forward to the Tier 2 Screening.
Tier 2 Screening
The Tier 2 Screening will evaluate which of the preliminary alternatives (from the Level 1 Screening) best meet the primary purpose and need, while also considering the degree to which these alternatives meet the secondary purpose and need, their impacts to the natural and human environment, estimated project costs, and overall feasibility. Only the alternatives that meet these criteria will be advanced for consideration as Reasonable Alternatives.
The alternatives that are not eliminated through the Tier 2 Screening process will be further refined through preliminary engineering before detailed impact analyses begin for the environmental assessment. The preliminary design for roadway will include details such as number of lanes, horizontal and vertical alignments, typical sections, right of way limits, intersection layouts, and construction limits.
Each reasonable alternative will be designed to a similar level of detail. Once the preliminary design work is complete, the potential effects of the alternatives will be identified and compared at an equal level of detail as required under NEPA. The reasonable alternatives will be detailed in the NEPA document with the ultimate goal of selecting a Preferred Alternative that would meet the overall purpose and need of the project while avoiding and minimizing environmental impacts to the greatest extent practicable.