Interregional Improvement Program (IIP)

The Interregional Improvement Program (IIP) is funded from 25 percent of the funds made available for transportation capital improvement projects under the STIP. This program targets projects that are needed to improve interregional movement of people and goods. Caltrans recommends to the California Transportation Commission (CTC) the selection of these projects, which can include state highway improvements, intercity passenger rail, mass transit guideways, or grade separation projects. SANBAG participates in this process by supporting or recommending the most cost effective projects for implementation.

The IIP apportionment is distributed by type of project with 40 percent available for flexible use in urban or rural areas, at least 9 percent for intercity rail improvements, which can include commuter rail and grade separation projects, and the remainder is for improvements to the interregional road system outside urbanized areas.