Interstate 215 Bi-County HOV Gap Closure
San Bernardino, Colton, Grand Terrace, Riverside

SANBAG worked with the Riverside County Transportation Commission (RCTC) and the California Department of Transportation (Caltrans) to complete preliminary engineering and environmental studies to add a carpool lane in both directions on Interstate 215 between San Bernardino and Riverside. Caltrans is now the lead agency in the construction of this 7.5-mile project extending from the Orange Show Road interchange in San Bernardino to the 60/91/215 interchange in Riverside and crosses the cities of Colton and Grand Terrace.


Aerial footage of the current "Spring Sting."


Caltrans Interstate 215 Bi-County HOV Gap Closure Project Fact Sheet

Acrobat pdf Caltrans Project Fact Sheet (redirect to

Caltrans Home Page:

  • Project Overview
  • Traffic Data & Studies
  • Cost & Schedule
  • Project Contacts

Project Overview & Significance

SANBAG and RCTC are shared responsibilities and costs for the Project Approval/Environmental Document phase of the I-215 Bi-County High Occupancy Vehicle (Carpool Lane) Gap Closure Project. Caltrans is the lead agency during construction.

The carpool lane addition will occur by rebuilding the outside and inside freeway shoulders and restriping the lanes to allow for three general purpose lanes and the new carpool lane in both directions. Railroad bridges will be rebuilt, and bridges crossing the Union Pacific railroad tracks, Interstate 10 and the Santa Ana River will be widened. Efforts are being made to limit property acquisition along the freeway.

The project replaces a previous proposal to add both a carpool lane and a general purpose lane in both directions to this section of freeway. Revising the project to add only carpool lanes at this time will reduce costs and allow the project to advance.

The project will close the gap between carpool lanes being built north of Orange Show Road in San Bernardino and south of the 60/91/215 interchange in Riverside. The lanes are designed to encourage ridesharing through carpools and vanpools and improve the efficiency, safety and operations of traffic moving between the two counties.

SANBAG has long-term plans to add a new northbound and southbound general purpose lane in this area by 2040.
Two separate but related projects also are in the planning stages along this section of I-215 – reconstruction of the Mt. Vernon/Washington Street interchange in Colton and the Barton Road interchange in Grand Terrace.    


Commuting and Traffic Data

Source: Caltrans and Southern California Association of Governments.

  • 80% of San Bernardino County commuters and 79% of Riverside County commuters drive to work alone each day.
  • San Bernardino County commuters spend an average of 43 minutes each way, traveling an average of 23.3 miles in each direction. Riverside County commuters spend slightly more time on the road – an average of 46 minutes each way, traveling 25.1 miles each way.
  • Approximately 160,000 vehicles per day travel this section of I-215. An average of 10,000 vehicles per hour travel during peak commute times.
  • By 2040, an estimated 335,000 vehicles per day are expected in this area, and average peak hour traffic counts are expected to grow to 21,000 per hour.
  • Up to 18,000 trucks move freight through this area each day, with 34,000 projected daily by 2040.
  • Forecasts show a demand for carpool lane use by 97,000 vehicles per day by 2040.
  • Traffic delays are common for northbound and southbound travelers during peak commute times, particularly for southbound motorists in the morning hours and northbound motorists in the late afternoon and evening hours. Delays are much greater on Friday evenings and holiday weekends.

Engineering & Environmental Studies

The Project Approval/Environmental Document phase of work required the completion of a number of technical studies. Engineering studies included traffic volumes, mapping, public utilities, geotechnical reports, material reports, drainage and storm water reports and right of way needs. Environmental studies were conducted to determine how the project may affect the area. These included studies of noise, air quality, hazardous materials, water quality, floodplains, community impacts, cultural and historic properties and sensitive plants and wildlife.

Noise studies help determine whether residential sound walls need to be built next to the freeway to help reduce noise. Residents near potential sound wall locations were asked to participate in the process.

The results of these studies were used to prepare drawings of the proposed improvements, develop cost estimates and prepare for future phases of the project – final design, right of way acquisition and construction.

Estimated Project Cost and Funding

The full project cost through construction is estimated to be $177.7 million. This estimate is subject to change, based on future cost escalations.

Funding for the carpool lane gap closure project is provided in part by Measure I, the half-cent sales tax for transportation improvements in San Bernardino County, and Measure A, the half-cent sales tax for transportation improvements in Riverside County. The agencies also pursued state and federal funding sources.

Estimated Project Schedule

The following schedule assumes no unforeseen delays and is contingent upon receiving funding:

  • The Project Approval/Environmental Document phase is expected to be completed by spring 2011.
  • Final design and right of way acquisition are estimated to be complete by Fall 2012.
  • Construction started in early 2013 and is expected to be complete by mid-2015.

Contact Us

  California Department of Transportation
Public Affairs Office
464 W. Fourth Street, 6th Floor
San Bernardino, CA 92410 / 909.383.6291