Question: 99 tunnel how many lanes?
Answer: The SR 99 Tunnel is a single tube that measures 9,270 feet (2,830 m) long and 52 feet (16 m) wide, carrying a double-decker highway that is 32 feet (9.8 m) wide and has two lanes in each direction. Each deck has two 11-foot (3.4 m) lanes, an 8-foot (2.4 m) west shoulder, and a 2-foot (0.61 m) east shoulder.