with increased road and marine traffic, a bill was introduced in 1961 by state senator richard j. dolwig to fund a new fixed high-level bridge to replace the 1929 lift-bridge. the modern span, which began construction on 1961-07-17, opened for traffic in 1967 at a cost of . the originally designed upgrade would retain the existing lift span (along with the attendant delays due to passing ship traffic), adding a second deck to the truss spans and widening the existing trestles to four lanes, but the california toll bridge authority added to the project budget in september 1961 to replace the existing lift span with a fixed high-level double-deck span, which would have been similar in appearance to the nearby 1956 richmond–san rafael bridge.