The US 84/285 (St. Francis/St. Michael’s) Interchange Study (Study) is being conducted in accordance with the NMDOT’s Location Study Procedures (2015) – the policy document followed by the NMDOT to comply with federal transportation planning and environmental regulations. This guidebook outlines the following phases of project development:

Project Phases of development

The current Study is one of several steps that were identified in the St. Francis Dr.  through City of Santa Fe Corridor Study (Bohannan Huston, Inc. 2010). This analysis was based on a macro-level evaluation that lacked the detail needed to make final design recommendations for any given area. The previous Phase IA St. Francis/St. Michael’s Interchange Alternatives Report (Radian 2018) and current Phase IB Study broaden the investigation of the existing interchange and provide a more detailed analysis of possible improvements.

The current phase of the Study consists of a Phase IB Detailed Evaluation of Alternatives (PDF), which is a continuation of the previous Phase IA Report (PDF). The previous Phase IA Report compiled information on the existing conditions and constraints, established the need for action, developed Study alternatives, and performed an initial screening of those alternatives. The Phase IA Report identified the nine alternatives shown below and compared their benefits and disadvantages. Based on this evaluation, four alternatives were eliminated from further consideration and five alternatives were advanced into Phase IB and evaluated in detail. 

Eliminate from Further Evaluation

  • Re-stripe Existing St. Francis Dr.
  • Modern Roundabout
  • Single Point Urban Interchange
  • Diverging Diamond Interchange

Alternatives Evaluated in Detail

  • No-Build
  • Signalized Intersection
  • Diamond Interchange
  • Ramp Reconfiguration
  • Split Bridge Interchange

The Phase IB Study evaluated the five remaining alternatives in terms of physical deficiencies, traffic operations, safety, bicycle and pedestrian improvements, environmental considerations, constructability and management of traffic, and costs (link). In addition, the Phase IB Study included an option whereby St. Michael’s Dr. would be constructed as a four-lane roadway within the interchange, in recognition of on-going City of Santa Fe plans for a future road diet study on St. Michael’s Dr. Several minor intersection alternatives were also considered at Siringo Road/St. Francis Dr. , West San Mateo Road/St. Francis Dr., and the southbound off-ramp intersection at St. Michael’s Dr.

Based upon the detailed evaluation, the Phase IB recommended alternative is the Ramp Reconfiguration with the four-lane option on St. Michael’s Dr. and the Siringo Road/St. Francis Dr. intersection configured to include dual left-turn lanes from northbound St. Francis Dr. to westbound Siringo Road (link). Following the public meeting and close of the comment period, the team will review the public input and make adjustments to the Study where needed. The Study is expected to be completed in Winter 2023/2024. Once the Phase IB report has been finalized, Phase C environmental documentation and Phase D preliminary design will follow.

Study Team Participants

new mexico department of transportation
federal highway administration

The Study Team is being led by the NMDOT in cooperation with the Federal Highway Administration, with the following key representatives.

Radian Engineering, LLC is the principal engineering consultant for the Study.

barr engineering logo

Barr Engineering is a subconsultant that provides environmental investigations and documentation for the Study.

design office

Design Office is participating in the Study to address bicycle and pedestrian needs.

city of santa fe
Santa Fe Metropolitan Planning Organization

The City of Santa Fe and Santa Fe Metropolitan Planning Organization are also participating agencies on the Study Team.