This is why you can't change lanes when driving westbound on the Tacoma Narrows Bridge

Q: When entering the Tacoma Narrows Bridge on westbound state Route 16, a large overhead sign warns drivers: "Do not change lanes on bridge." Is this merely a caution sign, or can drivers be cited for changing lanes on the bridge? — Ken

A: My fellow drivers, I'm noticing a trend lately where some of you see a posted sign on a roadway, presumably placed there by law enforcement, and still wonder whether that sign needs to be obeyed.

You should obey these signs. Law enforcement doesn't post them as a friendly suggestion.

I'm not saying you're definitely going to get a ticket if you change lanes on the westbound Narrows bridge after that sign explicitly tells you not to, but a Washington State Patrol trooper could pull you over and write you a ticket if you're flouting such traffic-control devices.

According to Sgt. James Prouty, you'll be violating RCW 46.61.140 if you changed lanes on the bridge after the sign says not to. That state law says, in part: "Official traffic-control devices may be installed prohibiting the changing of lanes on sections of roadway and drivers of vehicles shall obey the directions of every such device."

If a trooper catches you changing lanes on the westbound span of the bridge, you can get a $136 ticket, Prouty said.

That sign is there for a reason. If you've driven over the bridge, you know the lanes are grated, making for a white-knuckle drive in the wind or rain. The grates mean the roadway has a slicker surface, which makes changing lanes potentially very dicey.

Built in 1950 to replace Galloping Gertie, the bridge that went down in 1940, "The bridge was designed to let wind pass through and they were basically a safety measure and structural measure installed on that bridge when it was rebuilt," said Cara Mitchell, a spokeswoman for the state Department of Transportation.

"Those grates are slippery. They have a different surface on them than asphalt, and when cars drive over them, they can actually lose traction."

The newer, eastbound Narrows bridge doesn't have a grated surface, and you're allowed to change lanes, Mitchell said.

This story was originally published May 27, 2018 at 8:00 PM with the headline "This is why you can't change lanes when driving westbound on the Tacoma Narrows Bridge."