An interchange on Interstate 25 at Richards Avenue is among ideas being considered for improving traffic flow in the I-25 corridor between N.M. 599 and Old Pecos Trail.

Reducing the speed limit to 65 miles per hour on the freeway south of Santa Fe, adding auxiliary lanes and extending Gov. Miles Road to Rodeo Park Drive are among other ideas that were studied by CH2MHill, a global consulting firm hired by the state Department of Transportation.

The state has spent almost $373,000 so far on researching ways to improve the highway corridor, which crosses one of the fast-developing areas around Santa Fe. Marron and Associates is doing the environmental impact study.

The ideas, which haven't yet been ranked in any order of preference, will be presented to the public at a meeting Aug. 20. Comments will be considered about how the project would affect bikers, walkers and horse riders as well as cultural and natural resources.

Among the ideas:

Adding an interchange at Richards Avenue.

According to the study, this would provide additional access to I-25 and "improve system connectivity. This is particularly beneficial for emergency vehicle access, and for transit connectivity with the proposed Rail Runner station on I-25 between Cerrillos Road and Richards Avenue."

The study also found that the interchange could help relieve traffic for people who use the Santa Fe Community College district area.

The idea has been floated for several years in Santa Fe.

Adding new auxiliary lanes.

The lanes "would provide the same level of operations as a six-lane freeway between on- and off-ramps while providing the length necessary for traffic weaving onto and off the freeway," the study stated. The lanes also would mean freeway widening wouldn't be required between one ramp and the next on-ramp.

Reducing the speed limit in the corridor.

The study found "it is typical for urbanized areas to have lowered speed limits, to 65 mph, or even lower. The lower speeds are necessary because of congestion, merging and diverging traffic, and the speed differential between through traffic and merging and diverging traffic. The lower speed limits decrease conflicts between vehicles, which, in turn, provide safety benefits."

Building an overpass to extend Camino Carlos Rey south to Rabbit Road.

According to the report, "Camino Carlos Rey provides good system connectivity because it is continuous north to Cerrillos Road ... It is also more central to Richards Avenue and St. Francis Drive, and has no frontage driveways south of Zia Road."

Adding a new section of frontage road west of Old Dinosaur Trail.

This idea "would bypass the privately owned portion of Dinosaur Trail and associated speed humps, connect with the proposed overpass at Rail Runner Loop, and improve multi-modal and road system connectivity," the study said.

Extending Gov. Miles Road to connect with Rodeo Park Drive.

Currently, plans call for the road to tie into Galisteo Road. This new idea would extend Gov. Miles Road instead direct traffic to Rodeo Park Drive, and to Rodeo Road and Sawmill Road, according to the study.

Finally, the study suggests improving entrance and exit ramps to existing interchanges.

Contact Kate Nash at 986-3036 or knash@sfnewmexican.com. Read her blog at www.greenchilechatter.com.

IF YOU GO

What: Open house on potential improvements in the I-25 corridor south of Santa Fe

When: Begins 5 p.m., presentation at 5:30 p.m., Aug. 20, 2009

Where: Genoveva Chavez Community Center, 3221 Rodeo Road

Information: For information and drawings, visit: http://nmshtd.state.nm.us/main.asp?secid=15443