STPP 3-2(27)28; CN 4051 Final Environmental Impact Statement EXECUTIVE SUMMARY This document presents the results of the Corridor Study conducted for the portion of U.S. Highway 89 (US 89) from Fairfield, in Teton County, to Dupuyer, in Pondera County. This document was prepared in conformance with the Montana Environmental Policy Act (MEPA) and the National Environmental Policy Act (NEPA) requirements, and contains the information required for an Environmental Impact Statement. This document identifies potential social, economic, and environmental impacts that would result from the proposed reconstruction, widening, and realignment of US 89 in this corridor. Mitigation measures to address potential adverse impacts are also identified. Proposed Action MDT is proposing to reconstruct, widen, and realign US 89 from approximately 5.8 km (3.6 mi) north of Fairfield (approximately 32 km (20± mi.) west-northwest of Great Falls) to a location approximately 0.6 km (0.4 mi) south of Dupuyer, for a total length of approximately 74.3 km (46.2 mi). Existing bridges, culverts, and stockpasses would be replaced, and new right-of-way will be required throughout the corridor. The Preferred Alternative would provide a 10.8 m (36 ft) paved width to include two 3.6 m (12 ft) driving lanes, and 1.8 m (6.0 ft) shoulders. Purpose and Need MDT has identified the US 89 corridor for improvements generally due to its outdated design, including inadequate passing opportunities, narrow shoulders, sharp curves, and poor operations due to the mix of recreational vehicles, trucks, and passenger vehicles. Another factor in its identification for improvements is the corridor’s attractiveness as a recreational route. The existing facility is a paved, two-lane, minor rural arterial traveling from Yellowstone National Park on the south, to Glacier National Park and the Canadian border on the north. US 89 is located roughly parallel to Interstate 15 (I-15) within the proposed study corridor, and serves as a more scenic alternate route between Great Falls and Glacier National Park. The proposed project is intended to enhance not only the safety and efficiency of this route, but also to provide recreation-related enhancements for those travelers. The purpose of the proposed project is four-fold. The overall intent is to: • Provide a facility with updated design features, • Improve safety of travel through the corridor, • Provide an acceptable Level of Service in the corridor through the year 2023, and • Provide enhancements for recreational users. ES - 1 STPP 3-2(27)28; CN 4051 Final Environmental Impact Statement The existing facility exhibits substandard horizontal and vertical curves, areas with poor stopping sight distance, poor intersection geometry, and substandard roadway width. Several bridges are also functionally obsolete and eligible for replacement. US 89 is regarded as one of the most scenic routes along the Rocky Mountain Front by many residents in this part of the state. Coupled with the fact that it provides access to/from both Yellowstone and Glacier National Parks, US 89 provides access to regional attractions such as Freezeout Lake, Teton Pass ski area, Bynum Resevoir, and some of the region’s most renowned archeological sites. Thus, this route serves as a recreational corridor for local, regional, national, and international tourists for a variety of destinations and in every season. Residents and business owners throughout the corridor have noted the high usage of the highway by bicyclists, and have expressed their desire to provide a safer and more attractive facility for those travelers. US 89 has been improved and widened on the north end of Fairfield, just south of the project terminus. As a part of this project, MDT also intends to assess opportunities for scenic pull-outs along the route. Provision of pull-outs will provide enhanced recreational opportunities as well as improved safety by reducing the number of vehicles stopping at inappropriate locations. Alternatives Analysis Through an active public involvement program, MDT has received input from agencies, elected officials, businesses, and local residents within the US 89 study corridor to develop, evaluate, and refine the alternatives presented in the EIS. General concerns raised through the public and agency involvement process included shoulder widths to accommodate bicyclists, preservation and/or enhancement of the aesthetic character of the corridor, and improving the general driving conditions, particularly in the northern portion of the corridor where substandard curves, inadequate sight distances, and steep grades are more prevalent. A set of evaluation criteria was established to help guide the refinement of the alternatives developed under this study. To be considered for further evaluation, all alternatives had to affirmatively answer the following questions: • Does it meet MDT standards? • Does it follow AASHTO guidelines (unless prescribed by MDT standards)? • Are the improvements cost effective? • Does it adequately consider impacts to the built and natural environments? • Does it provide for bicycle and pedestrian improvements? • Does it adequately consider the scenic value? • Does it encourage tourist travel in the corridor? Several alignments, typical section widths, and other design features were evaluated during this process. ES - 2 STPP 3-2(27)28; CN 4051 Final Environmental Impact Statement Typical Section Width Alternatives The existing typical section width of US 89 within the study corridor does not meet current design standards for a Rural Minor Arterial, as defined by MDT. The existing facility provides only the minimum driving lane width (3.6± m [12.0± ft.]), and narrow to non- existent shoulders. This condition was forwarded as the “No-Build” alternative, and compared to two additional typical section width alternatives described below. The first typical section width alternative is based on the Route Segment Plan, which identifies a future width for US 89 of 9.6 m (32.0± ft) from Fairfield to just north of Choteau, and narrowing to 8.4 m (28.0± ft) from Choteau to the end of the route. Based on input from the local communities within the corridor, a second, wider typical section width alternative was developed to address the desire to encourage bicycle and pedestrian travel in this corridor. This 10.8 m (36 ft) typical section width is the preferred width for the entire corridor. Alignment Alternatives Throughout a large percentage of the corridor, there are only two alternatives with regard to the alignment: the No-Build Alternative, which would provide routine maintenance to the existing facility, and the Build Alternative, which would reconstruct the roadway generally along the existing alignment, but offset approximately 15 m (50 ft) east of the existing centerline. An offset alignment is preferable for several reasons. Construction of a new alignment immediately adjacent to the existing allows for the new roadway to be constructed while the existing roadway is still completely open to traffic. This reduces potential hazards to travelers in the corridor, and minimizes any increased travel time costs due to construction delays. Some delays, however, are inevitable due to curiosity slowing. An offset alignment also reduces the number of individual parcels that will be required for new right-of-way by acquiring new right-of-way only on one side of the new roadway. The new construction limits (including cuts through hills and fill slopes in low lying areas) will incorporate the majority of the existing roadway embankment and paved surface. Any portion of the existing roadway or embankment that is not fully incorporated into the new roadbed or side slopes will be re-graded and seeded with desirable vegetation. An offset alignment can also result in a savings in construction costs associated with earthwork and traffic control. A shift to the east was preferred due to the lack of development and/or agricultural activity or any other sensitive resources in the abandoned railroad right-of-way located immediately parallel to US 89 through the middle third of the corridor. Fourteen additional alignment alternatives were evaluated in six general locations throughout the corridor. These alignment alternatives were intended to provide a range of possible geometric improvements in areas with substandard curves. The alternatives ranged from minor curve corrections to satisfy minimum standards, to major alignment deviations from the existing alignment onto new alignments. The location of these alignment alternatives is depicted in Figure S-1. Table S.1 provides the screening analysis of these alternatives. ES - 3 STPP 3-2(27)28; CN 4051 Final Environmental Impact Statement Figure S-1 Alignment Alternative Locations Alignment Alternatives M and N Alignment Alternatives J, K, and L Alignment Alternative I Alignment Alternatives F, G, and H Alignment Alternatives D and E Alignment Alternatives A, B, and C Legend: Alignment Alternative Location Offset alignment to the east of existing centerline Reconstruction along existing alignment centerline ES - 4 STPP 3-2(27)28; CN 4051 Final Environmental Impact Statement Table S.1 Screening Evaluation Summary Alignment Status Rationale Alternative No Build Retain Does not meet purpose and need, or the evaluation criteria, but is being retained for comparison as the baseline condition. A Retain Improves the roadway geometry through the Spring Creek area with minimal disturbance to the surrounding built and natural environment.