What’s black and white with yellow stripes?

No, not a bridge, but a road with a bridge! So I’ve been doing a lot of flying lately – from LAX to IAD, then from IAD to MCO and back – and quite a bit of driving (or being driven) too – from VA to PA and back – and it started to become really obvious to me that when I saw a patch of lighter pavement, it was a small bridge or overpass. Have you ever noticed that too?

My theory is that the bridges are made with a different paving material (concrete vs. asphalt) for two possible reasons: 1. to ensure that they are sturdy enough to hold under the weight of all the passing traffic and 2. to use the lightest/least possible material. Asphalt can be poured onto the base layer of concrete for roads directly on the ground, but when it comes to bridges, adding that extra weight isn’t necessarily worth the benefits of easier maintenance. So while you’ll find black asphalt roads most everywhere, once you approach a bridge, don’t be surprised if it’s white(ish). Then again, maybe you’re not a nerd like me, noticing and trying to understand this difference. Just thought I’d share one of the many random things I notice and think about as I go about my daily life.