Existing Conditions
The interchange experiences frequent congestion due to residential development, traffic generated by several shopping malls and the close spacing with the SR 163/I-8 freeway-to-freeway interchange. In addition, 4 significant weave areas are present on SR 163 and Friars Road, further aggravating the congestion.

Alternatives Development
During early alternatives development, 18 different alternatives were studied for this complex interchange location. 2 feasible build alternatives were initially identified and a Traffic Operations Analysis was completed to validate the alternatives.

Locally Preferred Alternative
The current “locally preferred alternative” consists of:

• Widening Friars Road from 6 to 11 lanes to handles the heavy future volumes on Friars Road.
• Adding a southbound auxiliary lane on SR 163 starting at Genesee Avenue to handle the large volume of southbound vehicles desiring to exit at Friars Road.
• Elimination of the off/on-ramp weave beneath the Friars Road overcrossing by closing the Friars Road westbound to SR 163 southbound loop on-ramp.
• Constructing a new “flyover” bridge from eastbound Friars Road to southbound SR 163 and eastbound I-8. The new structure eliminates the freeway weave for Friars Road southbound on-ramp traffic with southbound SR 163 traffic desiring to travel to westbound I-8.
• Construction of a new bridge that handles southbound SR 163 to westbound I-8 traffic, along with Friars Road traffic desiring to proceed to westbound I-8.
• Elimination of the weave segments on Friars Road by closing the northbound SR 163 to eastbound Friars Road off-ramp and improving the flopped partial cloverleaf configuration.

Value Analysis Study
A formal Caltrans Value Analysis Study assisted in the development of the locally preferred alternative and identified numerous cost saving measures. After careful review of the original feasible 2 alternatives, 1 of the alternatives was determined to be infeasible due to unacceptable environmental impacts due to the required relocation of 2 major power transmission towers located within the interchange area.

Complex Interchange Geometrics
Alignment geometrics and grading for the locally preferred alternative have been completed using Computer Aided Civil Engineering (CAiCE) software. Construction staging plans have been completed to study construction impacts to local businesses. Logical project phasing was developed to identify separate fundable project phases. 

Traffic Studies
An analysis of the existing freeway and roadways within the project area was completed by Linscott, Law and Greenspan (LLG). 2 existing traffic models, the City’s Mission Valley Model and SANDAG’s 2030 Series 10 Model were utilized to create a hybrid model for the development of future forecast volumes. The traffic study was awarded an Association of Environmental Professionals (AEP) Merit Award.

Technical Studies
Numerous engineering studies have been completed during the PA/ED phase including:

• Geotechnical Design/Structures Foundation Reports
• Drainage/Hydrology Report
• Location Hydraulic Study (LHS)
• Storm Water Data Report (SWDR)
• River Scour Analysis
• Visual Impact Assessment (VIA)
• Noise Study
• Noise Abatement Decision Report (NADR)

Project Approval Documents
A preliminary Freeway Agreement for proposed modifications has been prepared. This agreement will supersede an existing Freeway Agreement between the City and State for SR 163.  The project requires environmental clearance under both the California Environmental Quality Act (CEQA) and the National Environmental Policy Act (NEPA). The environmental document is an EIR/CE.  The Draft Project Report and Draft EIR have been completed and are currently being reviewed.