Skip to content
Project # Z566310000 / Federal # 0A31034

Seward Highway MP 105-109.5,
Windy Corner to Rainbow Point


What’s New (March 2023)

The Seward Highway mileposts (MP) 105-109.5, Windy Corner to Rainbow Point project has been incorporated into the Seward Highway MP 98.5 and 118, Bird Flats to Rabbit Creek project, also known as the Safer Seward Highway project.

The project is now being managed and developed out of the Commissioner’s office and is known as a Transportation X (TrX) project.

Please visit the new project website for new information and upcoming events. 


You provided comments and feedback and we heard you! The project formerly known as Seward Highway: Windy Corner (MP 105-107) is now Seward Highway MP 105-109.5, Windy Corner to Rainbow Point.

In response to public comments on the Draft Environmental Assessment (EA) completed in early 2020, the Alaska Department of Transportation and Public Facilities (DOT&PF) expanded the project scope. Key changes include:

  • Extending the project further north to Rainbow Point for a more expansive safety improvement corridor
  • Evaluating the feasibility of obtaining materials for the project from the new road realignment to reduce impacts to Chugach State Park. The March 2020 Draft EA proposed obtaining material from separate material locations within the Park at MP 104 and 109.
  • Consideration of a separated multi-use pathway connecting the Windy Corner and Rainbow trailheads

Development of a new Environmental Document is underway for the expanded project.

Project Overview

DOT&PF is proposing to construct safety improvements along the Seward Highway between Windy Corner, at MP 105, and Rainbow, at MP 109.5 (see figure below). The Seward Highway within the project corridor traverses Chugach State Park (CSP) and is a National Scenic Byway and All-American Road known for impressive scenic views, wildlife, and recreation access. This stretch of road is a designated Safety Corridor. This is the only road connecting Anchorage with Kenai Peninsula communities and it is heavily trafficked by residents, visitors, businesses, and industry.

Objectives of this project are to decrease high-severity crashes and improve traffic operations to alleviate traffic congestion. Proposed improvements to meet project objectives include:

  • Realigning the highway to flatten curves at two locations with historically high rates of high severity (fatal and major injury) crashes
  • Adding auxiliary lanes for accelerating, decelerating, and turning traffic
  • Constructing turnouts, new recreational facilities, improved access to existing CSP facilities, and parking areas throughout the project corridor
  • Realigning segments of the Alaska Railroad Corporation’s tracks
  • Potentially constructing a separated non-motorized pathway between the Windy Corner and Rainbow trailheads

DOT&PF will continue to work collaboratively with the Alaska Department of Natural Resources (DNR) to improve CSP access within the project corridor, including potential improvements to existing CSP facilities and new CSP infrastructure.


The efforts to improve safety along the Seward Highway between Anchorage and Girdwood began in the early 2000s. A Categorical Exclusion (CE) was prepared for Seward Highway Safety Improvements, Indian to Potter Marsh, MP 105-115 project and the CE was approved in 2004 and reevaluated as a part of the smaller Seward Highway: MP 105-107, Windy Corner project, which kicked off in 2013. As a result of public feedback and consultation with the Federal Highway Administration (FHWA), the Class of Action was revised to an EA in 2017.

Agency scoping and public involvement was conducted in accordance with National Environmental Policy Act (NEPA) requirements to produce a Draft EA for the Seward Highway: Windy Corner (MP 105-107) project, which was completed in March 2020. After reviewing public comments, DOT&PF extended the project 2.5 miles between Windy Corner and Rainbow Point to address concerns. Public and agency scoping as a part of a new Environmental Document commenced in spring 2021 for the renamed project, Seward Highway MP 105-109.5, Windy Corner to Rainbow Point. These scoping efforts are detailed in the Scoping Summary Report dated August 2021.

Funding and Guidance

The proposed project is being advanced using a combination of state and federal funds and is being developed in accordance with FHWA guidelines. DOT&PF is conducting environmental analyses, preparing environmental documentation, and developing the design with input from the public as well as local, state, and federal agencies, including ARRC, DNR, Alaska Department of Fish and Game (ADF&G), National Parks Service, U.S. Army Corps of Engineers, Anchorage Fire Department, and others.

The environmental review, consultation, and other actions required by applicable Federal environmental laws for this project are being, or have been, carried out by DOT&PF pursuant to 23 U.S.C. 327 and a Memorandum of Understanding dated November 3, 2017, executed by FHWA and DOT&PF.