The North I-25 corridor includes the mainline freeway, the frontage road system, and the arterial cross-street intersections within and in close proximity to I-25 from north of I-40 to Tramway Road.  Recommendations are provided for the corridor including the interchanges at Comanche Road, Montgomery Boulevard/Montaño Road, Jefferson Street, San Mateo Boulevard/Osuna Road, San Antonio Drive/Ellison Street, and Alameda Boulevard.  The improvements identified for I-25 in the Paseo del Norte Interchange Study DEIS were refined based on the findings of this study and the proposed modifications are reflected in the recommendations.  The Tramway Road/Roy Road interchange was recently improved and further improvements were not identified by this study.  

Design Year Traffic Performance Expectations

Based on the design-year 2030 traffic forecasts and traffic analyses completed for this study, some congestion is projected under design-year conditions.  However, this finding does not understate the need for improvements in the North I-25 corridor.  Congestion is projected to be widespread and will affect most of the major roadways within the metropolitan area.  Moreover, the feasibility of major improvements to the arterial street system in the area east of the Rio Grande will be limited.  For this reason, the Albuquerque region will need to get the most out of its transportation system to meet future traffic demand.  In some cases, capacity improvements can be made but in others, the existing capacity will need to be managed.  High-capacity corridors like I-25, which passes through the middle of the region, will continue to be highly utilized so investments into the I-25 Corridor will provide value to the region and should be programmed even if full mitigation of congestion cannot be achieved.  Furthermore, managing congested traffic conditions would be difficult with the existing configuration of I-25.

Freeway Mainline

The Recommended Build Alternative provides four basic lanes from north of I-40 to Paseo del Norte in both travel directions.  See the Executive Summary for typical section drawings and the plan view layout drawings.  In addition, 12 to 14-foot shoulders and auxiliary lanes to supplement on and off-ramp operations are provided, as appropriate.  The bottleneck in the northbound direction at Comanche Road is eliminated, and the appropriate number of lanes is provided southbound exiting the I-25/Paseo del Norte interchange.  Lane balance and lane continuity are provided in both travel directions. 

The reduction of conflicts along the study corridor was accomplished through the use of braided ramp pairs and by removing ramps to eliminate weave sections along the mainline freeway.  Collector-distributor (CD) roads were incorporated at the San Mateo Boulevard/Osuna Road and San Antonio Drive/Ellison Street interchanges as well. 

The proposed mainline improvements also include ITS applications to facilitate management of the corridor including ramp metering at selected on-ramps.  While much of the system is expected to be installed by other projects and the specific elements of the ITS system are not defined by this study, costs for an ITS system are included in the project cost estimate. 

Several modifications to the improvements included in the I-25/Paseo del Norte Interchange DEIS are recommended which will need to be addressed in future environmental documents and the Interstate Access Change Request (IACR) for the interchange.  These modifications are listed below:

• Northbound I-25


• The Jefferson Street on-ramp is eliminated.


• Ramp metering is recommended for the San Mateo Boulevard/Osuna Road on-ramp.


• The off-ramp north of San Antonio Drive to the northbound frontage road, which would have provided local access to Paseo del Norte and other local streets, is eliminated.  The recommendation is to combine this access with the San Antonio Drive off-ramp.  A CD road is provided over San Antonio Drive to intersect the frontage road at the approximate location of the slip ramp proposed in the DEIS.


• A two-lane ramp diverge is proposed at the Alameda Boulevard off-ramp.

• Southbound I-25


• The Alameda Boulevard off-ramp is moved further north which requires widening and access modifications to the southbound frontage road.


• The San Antonio Drive on-ramp is eliminated.


• A two-lane off-ramp is proposed to provide access to San Mateo Boulevard/Osuna Road as well as access to Jefferson Street via a CD road over San Mateo Boulevard.  A slip ramp diverges from the two-lane ramp roadway to the southbound frontage road to provide access to San Mateo Boulevard and Osuna Road.  The two-lane ramp roadway continues south with one lane dropping to a loop ramp to southbound San Mateo Boulevard and the other continuing to the frontage road south of San Mateo Boulevard/Osuna Road to provide access to Jefferson Street.  The CD road is braided with the San Mateo Boulevard/Osuna Road on-ramp.


• The San Mateo Boulevard/Osuna Road Interchange is reconstructed (may be considered a separate project similar to the reconstruction of the Alameda Boulevard interchange).


• A lane is added to southbound San Mateo Boulevard starting at the loop ramp and ending at Academy Road.


• An advance u-turn is provided on the north side serving the south-to-north movement.


• Ramp metering is recommended for the San Mateo Boulevard/Osuna Road on-ramp.

The direct off-ramp to Jefferson Street is relocated as described above.

Interchanges

The following summarizes the key modifications recommended for the interchanges along North I-25.  Refer to the 3D Photo Simulations drawings for more information.  Note that the queuing expected with ramp metering will be better accommodated with new bridge structures because left-turn lane improvements are included within the interchanges.  Improvements to the intersection lane configurations are included at each interchange.

Interchanges 3D Photo Simulations (11mb pdf)

1. Comanche Road Interchange: Reconstructed, full access retained, compressed diamond layout, on-ramps metered, advance u-turns on both sides, access management on west side.
• Local service road from Aztec Road eliminates access to the northbound frontage road between Aztec Road and Comanche Road.
  
  
2. Montgomery Boulevard/Montaño Road Interchange: Reconstructed, full access retained, compressed diamond layout, on-ramps metered, advance u-turns on both sides, access management on east side.
• Grade-separated local service road which maintains full access to and from Pan American East Drive.
• Loop ramp eliminated.
  
  
3. Jefferson Street Interchange: Widen existing bridge structure, access reduced, compressed diamond layout, on-ramp metered, advance u-turns on both sides, access management on east side.
• Northbound on-ramp eliminated.
• Southbound off-ramp relocated north; combined with San Mateo Boulevard/Osuna Road off-ramp continuing grade-separated over the arterial via a CD road and braided with the San Mateo Boulevard/Osuna Road on-ramp.
• Realignment of Restaurant Lane and access easement extensions associated with Monroe Street connection to Jefferson Street.
  
  
4. San Mateo Boulevard/Osuna Road Interchange: Reconstructed, full access added, compressed diamond layout, on-ramps metered, advance u-turn on north side, access management on west side.
• Traffic signal control at Pan American East Drive to remain.
• Fourth lane added to southbound San Mateo Boulevard from the proposed loop ramp.
  
  
5. San Antonio Drive/Ellison Street Interchange: Existing bridge and layout, access reduced, access management on east side.
• Northbound off-ramp braided with new San Mateo Boulevard on-ramp.
• Northbound on-ramp relocated north, braided with the Paseo del Norte directional off-ramp.
• Southbound off-ramp eliminated.
• Southbound on-ramp eliminated.
  
  
6. Alameda Boulevard Interchange: Reconstructed, full access retained, compressed diamond layout, advance u-turns on both sides, access management on both sides.

Ramp Metering

Ramp metering is recommended for the North I-25 corridor from Comanche Road to Paseo del Norte.  A ramp metering evaluation and study should be conducted to refine the approach for implementation and subsequent operation (e.g., fixed time, metered-at-demand, traffic responsive).  Responsible agencies will need to consider if resources (e.g., staff, funding, equipment) can be made available to support ramp metering programs and if these systems can be effectively maintained.  In addition to these resources, staff must also consider how they intend to enforce ramp meter compliance, and should investigate if law enforcement is committed to the ramp meter program.

Modal Elements

Alternative transportation modes are accommodated in the Recommended Build Alternative as follows:

• Pedestrians: Sidewalks are provided for pedestrians along both sides of each crossing arterial street through the I-25 interchanges.  Typical sidewalk widths are a minimum of six to eight feet.


• Bicycles: On-street bicycle lanes are incorporated into the interchanges identified for reconstruction.  Bicycle trail improvements are shown connecting both sides of Montgomery Boulevard to the North Diversion Channel trail.  The grade-separated structure at the Bear Arroyo crossing of I-25was incorporated into the conceptual design (City of Albuquerque project).  A grade-separated structure is also included as part of the Paseo del Norte interchange improvements.


• Transit: The costs associated with the I-25 bridges over San Mateo Boulevard/Osuna Road were increased to accommodate future bus rapid transit (BRT).  Providing improvements to I-25 will improve the reliability of travel within the corridor which would make it available for use by ABQ Ride transit routes (using general purpose travel lanes).


• Managed Lanes: Full shoulder widths are provided along both sides of mainline I-25 in both travel directions.  Future managed lanes could be added to the North I-25 corridor if the shoulder width is utilized and design exceptions are obtained for the reduced shoulder widths.