1-minute voter guide: Measure G

• Supporters anticipate the tax bringing in $350 million each year, if over 50% of voters approve it.

How it works: Labor unions and infrastructure construction firms collected signatures to qualify the measure for the ballot, but the revenue would go to the San Diego Association of Governments to pay for road, highway, transit, beach reclamation and stormwater projects.

• SANDAG plans and engineers the projects, then uses the local funding as matching funds to win state and federal grants to cover their full budgets.

State of play: Delays at the SANDAG have deprived the measure of a ready-to-go plan for an airport transit connection, but supporters still hope the tax could fund that project if decision-makers figure out how they want to do it.

• In its place, moving the train tracks off the Del Mar Bluffs, where they're threatened by coastal erosion, has become the measure's marquee project.

Case for and against: Supporters argue the funding is necessary to build a transit system capable of lowering the region's carbon footprint enough to meet state climate targets.

• Opponents argue SANDAG has been mired in a series of scandals for nearly a decade and can't be trusted with new taxpayer revenue.

What's next: Residents will keep paying the county's existing sales tax, TransNet, through 2048.

• But SANDAG borrowed against that future revenue to build projects like the Mid-Coast Trolley and the I-15 express lanes.
• Without new funding, most of those taxes will go to paying off debt, until 2035 when SANDAG expects to again have about $700 million in TransNet funds for regional infrastructure.

The bottom line: Because SANDAG dramatically overstated how much TransNet would generate, that local revenue after 2035 won't be enough to fulfil everything promised in that program — let alone any new projects the region has pursued in the years since.