The I-215 Placentia Avenue Interchange in Perris is the first construction project of the Mid County Parkway, a new 16-mile transportation corridor between the San Jacinto and Perris valleys. The Mid County Parkway is designed to reduce travel times between these areas. Please see the Mid County Parkway Ramona Expressway page for details about this corridor.

Designed to meet the needs of a growing population, the Placentia interchange project provides a new way to enter and exit I-215. The new interchange is located between Ramona Expressway to the north and Nuevo Road to the south. It was designed to improve access, traffic flow, and air quality by adding on-ramps and off-ramps to Placentia Avenue, realigning East Frontage Road, widening the Placentia Avenue overcrossing, and adding lanes to Placentia Avenue between Harvill Avenue and Indian Avenue.