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The Interstate 5 Freeway (I-5) through the cities of Irvine and Tustin is essential to Orange County’s mobility, economy and quality of life. It is a major commuter and commercial corridor, and serves as a “bridge” that connects Orange County to Los Angeles County and San Diego County.

Today, this segment of I-5 is one of the most highly traveled and congested freeway corridors in the nation. Every day, more than 350,000 motorists drive this segment of I-5 through the cities of Irvine and Tustin, to connect with major residential, commercial, educational and employment destinations. Already at capacity, traffic projections show that nearly ½ million motorists will travel this stretch of I-5 by 2040.

To address this current and future traffic demand, OCTA and Caltrans are conducting the I-5 Irvine Tustin Project, a preliminary engineering and environmental study, in late 2014.

Funded by Measure M, Orange County’s voter-approved Transportation Investment Plan, the purpose of the study is to measure the estimated performance, feasibility and potential environmental effects of adding a new northbound (NB) and southbound (SB) general purpose lane, as well as various other capital and operational improvements, to I-5 adjacent to the cities of Irvine and Tustin.

Purpose and Need

Currently, the I-5 corridor within the project limits is experiencing congestion and long traffic delays due to demand exceeding capacity. The purpose of the project is to address existing and future traffic demand and congestion, and enhance freeway operations from I-405 to SR-55 as follows:

  • Increase the mainline/freeway capacity within the project limits with one additional lane in each direction
  • Improve the capacity of the ramps within the project limits
  • Improve operational deficiencies of merge and diverge areas within the project limits
  • Improve the existing auxiliary lanes operations
  • Optimize access of the existing HOV lane

The goal of the proposed project is to minimize environmental impacts as well as right-of-way (ROW) acquisitions within the project limits.

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