Leading Planning and Environmental Studies Focused on Improving Safety, Mobility and Reliability Along an Alaska Coastal Corridor

• Agile project management methodology boosted collaboration and reduced overlapping responsibilities
• Comprehensive stakeholder working group shaped corridor concepts and built support
• Global evaluation of innovative roadway designs prioritized safety in the unique environment
• Express Projects delivered immediate safety improvements at corridor’s high-risk locations

Winding through Chugach State Park, the Seward Highway between mileposts 98.5 and 118 is a vital route for tourists and other outdoor recreationalists drawn to the area’s natural scenery. This popularity creates heavy and unpredictable traffic. The constrained two-lane corridor has tight shoulders, sharp curves, informal pullouts, few passing opportunities, and occasional rock and icefall from bordering slopes, contributing to slowdowns and serious crashes. While congestion is most noticeable during busy summer months, most crashes occur when winter weather reduces safe driving speeds. As a result, this 20-mile segment is soon to be Alaska’s last designated safety corridor because of its higher-than-average number of fatal and serious-injury crashes. Despite 20 years of enforcement efforts and incremental safety improvements, deadly crashes have persisted.

Recognizing the need for a long-term solution, the Alaska Department of Transportation and Public Facilities (DOT&PF) began efforts to improve safety and mobility along the corridor. Following the successful rehabilitation of Seward Highway mileposts 75 to 90, HDR was hired in 2023 to lead development of the environmental document, including preliminary engineering and strategic communications focused on building consensus around a permanent solution for the corridor.

Using Agile Delivery

Seeking to expedite corridor planning and prevent inefficiencies, DOT&PF and HDR adopted the Agile project management methodology. Through this approach, we formed an integrated team with multiple regional transportation leaders, guided by the DOT&PF commissioner, and broke down work into smaller two-week tasks called sprints.

This innovative approach has positioned our project management, environmental, roadway and communications professionals to seamlessly collaborate with their DOT&PF counterparts rather than navigate a traditional chain of command. As a result, design revisions accelerated, duplication of work was reduced, and coordination across the project team improved. As team lead, we spearheaded two-week sprint meetings focused on completing tasks, including concept development, environmental noise and tunnel analysis and evaluation of safety improvements. With sprints now complete, the Agile framework continues to streamline communication and provide clear, timely project status updates.

Advancing Immediate Safety

Understanding that environmental documentation, final design and construction would span several years, our team prioritized quick improvements to improve safety while the larger project progressed. During sprint sessions, our designers collaborated with DOT&PF, the Alaska Railroad and local emergency medical response services to identify actions and projects that could improve safety in the corridor in the short term. Three projects were prioritized for immediate safety improvements in 2025 and 2026.

To reduce sudden stops and unexpected turns by drivers unfamiliar with the area, larger signs with bigger font were installed to identify attractions and warn of curves and pullouts. Updated milepost markers were also added at pullouts, allowing EMS to locate 911 callers more quickly.

A dedicated left turn lane will be constructed in the summer of 2026 at the entrance to the McHugh Creek Recreation Area to reduce rear-end collisions and unsafe shoulder passings. In addition, the project team secured Highway Safety Improvement Program funding to blast and cut back rock slopes, install rock catchment systems, and repair drainage issues to reduce ice and rockfall onto a hazardous section of roadway at milepost 113.2.

Adapting Unique Designs

Exploring alternative configurations for the Seward Highway, our traffic safety professionals explored long-term safety performance of three preferred concepts:

• Three-lane undivided or two lanes with an alternating passing lane (2+1)
• Three-lane divided by a median
• Four-lane divided highway

While the three-lane undivided and four-lane divided options have safety evaluation guidance in the U.S. Highway Safety Manual, it does not address the less common divided three-lane configuration. To bridge this gap, our safety team turned to Scandinavia, where divided three-lane highways are more common and environmental conditions resemble Alaska’s.

We reviewed case studies, research, and best practices from Norway and Sweden. Using the Highway Safety Manual methodology for conventional two-lane highways, our engineers adapted the methods to incorporate the Scandinavian safety experience.

Results showed that a median-divided three-lane alternative could reduce crashes by up to 39%, compared to 36% for an undivided three-lane. Ultimately, the four-lane divided highway was found to reduce crashes by 68%, leading to its selection as the proposed action.

Building Consensus

Decades of disagreement among stakeholders and regulators had stalled earlier attempts to advance long-term improvements in the corridor. An unfinished environmental effort on a smaller section, combined with many of the same stakeholders, led DOT&PF to increase the project scope from 4 miles to 20 miles, reinforcing the need for consensus. To find common ground during the expedited two-year environmental documentation schedule, our team led a series of stakeholder working groups that included federal and local agencies, members of the public, and representatives of bicyclists, truckers and tourists.

Because the corridor aligns with endangered Beluga whale habitats, fish streams, eagles’ nests, residential communities, parks and trailheads, we walked stakeholders through the constraints and opportunities shaping the project. Their feedback, including considerations for Dall Sheep, park access facilities, rock-climbing areas and improved bike paths was critical in informing the environmental assessment (EA).

This collaboration has significantly accelerated the EA review process. Early participation by the Statewide Environmental Office allowed the agency to complete an expedited review of the draft EA, saving months. Similarly, the National Marine Fisheries Service issued an accelerated biological opinion on mitigation measures to reduce construction impacts on a nearby critical beluga whale habitat — viewing their stakeholder working group participation as early consultation.

Public review and comment of the EA concluded in early 2026. The comment period will be followed by additional agency review and approval. Major design is estimated to begin in 2026, and construction could follow soon after.