We all know the nation’s infrastructure is desperately in need of investment and overhaul (our own Tiffany Diehl sheds light on some of the worrying facts in her article Are Bridges in the U.S. Making the Grade? State Rankings Reveal a Grim Reality.) But when the infrastructure in question resides on one of the most seismically active metropolitan areas in the country, state transportation departments have an imperative to up the ante. Such is the case with one of the biggest engineering projects in California history, the replacement of the current south access road to the Golden Gate Bridge in San Francisco. Known as Doyle Drive or Route 101, the route is structurally and seismically deficient and, built in 1936, it’s also come to the end of its useful life.