Funding Our Transportation System

How is the 2021 Regional Plan funded?

Funding for the 2021 Regional Plan won’t be available all at once—rather, it will come into the region over time. Project implementation needs to be carefully phased based on anticipated revenue projections and other factors. The 2021 Regional Plan will include a detailed funding strategy that will be reviewed at the state and federal levels. The funding strategy must be built on a revenue forecast—based on trends for existing revenue sources as well as reasonable assumptions about potential changes in the future—of what the region will be able to afford through 2050. Numerous factors, ranging from the state of the economy to new state and federal legislation, can affect funding availability and use.

Where do funds come from? How can we invest them?

Funding for our transportation network comes from a variety of sources at the federal, state, and local levels. The majority of current federal and state funding sources have restrictions on their use, and we don’t have the authority to interchange them. These constraints come with specific provisions from Congress or the State Legislature. Restrictions may specify certain modes of transportation—such as highway, bus, rail, or bike/pedestrian projects—as well as when, where, and how funds must be used.

There also are constraints for which dollars can be used by SANDAG and which dollars are distributed to agencies such as Caltrans (for highway maintenance), transit agencies (for transit operations and maintenance), and the cities and county (for local streets and roads).

SANDAG has purview over a relatively small portion of the overall funds included in the Regional Plan, and therefore must continue to work creatively to determine how to best leverage and invest the available dollars. One way the San Diego region has supplemented scarce federal and state dollars for transportation projects is by establishing local revenue sources. Revenues from the countywide TransNet half-cent sales tax, other local taxes, developer impact fees, fares, tolls, and additional local sources now fund roughly half of our region’s transportation improvements.

What is TransNet? How do we use its revenues?

TransNet is a countywide half-cent sales tax dedicated to transportation improvements and environmental conservation in the San Diego region. Originally approved by voters in 1987, a 40-year extension of TransNet was approved by a majority of voters in 2004. As with other funding sources, the TransNet ballot measures included a list of specific projects with funding priority.

During the last 30 years, TransNet revenues have been leveraged to secure billions of dollars in federal and state matching funds to help complete hundreds of projects around the region—highway, bus, and rail projects as well as bike and pedestrian projects, local street repairs, habitat conservation efforts, and grant programs. Explore completed projects using the interactive TransNet Story Map at

More information about the TransNet program and its Independent Taxpayer Oversight Committee is available at