Purpose and Need
The Lone Tree Overpass will create a new north-south roadway connection extending Lone Tree Road between Butler Avenue to the south and Route 66 to the north. The roadway will be on a grade-separated bridge that will go over the BNSF Railway main line corridor and the United States Army Corps of Engineers (USACE) future Rio de Flag Channel. Much like the popular Fourth Street railroad crossing constructed in 2006, this new overpass will provide connectivity, traffic congestion relief on streets like Milton Road, San Francisco Street, and Beaver Street, and improved mobility to surrounding neighborhoods. The overpass connection will also complement the community’s need for multi-model options with bicycle and pedestrian access points connecting to the Flagstaff Urban Trail System (FUTS).
Project Area Map
- 2001 — The City of Flagstaff’s Regional Land Use and Transportation Plan revealed the need for an additional grade separated north-south connection into downtown Flagstaff.
- 2006 — Lone Tree Corridor Study established conceptual plans for the corridor.
- 2010 — Lone Tree Overpass Study developed project alternatives and a proposed alignment.
- 2018 — Flagstaff residents approved Proposition 420 to fund the design and construction of the Lone Tree Overpass and Proposition 419 to fund the Lone Tree Corridor Improvements.
- 2020 — Lone Tree Overpass Study Final Report Update updated recommendations and cost from the 2010 Lone Tree Overpass Study.
- 2021 - 2023 — Design: We Are Here
- 2024 - 2026 — Construction