The Spring Festival Travel Rush is the busiest time for bus drivers. However, for Mr. Yuan, a veteran driver on a trans-provincial bus line, business is declining. Especially recently, when it’s hazy.

"Normally I can drive 80 to 90 kilometers an hour. But when it's hazy, I have to reduce the speed to 40 to 50 kilometers an hour. Sometimes we even have to wait in the service zone. Passenger numbers are declining. I used to make two round trips. Now I only make one." Bus driver Mr. Yuan said.

This is the biggest road transport hub in Shijiazhuang city; bus lines here connect most provinces in Northeast China. 70% of those lines use expressways. But continuous smog is paralyzing nearby expressways, which often forces delays and cancellations.

"Because of the haze, this week we've had to cancel around 50 lines every day. That’s almost a fifth of our total transport capacity. Many lines have to switch to state highways. That takes much longer than expressways." Shi Lijun, vice director of SHijiazhuang Long Distance Road Network Hub, said.

Unreliable schedules and traffic hazards are forcing more people to turn to other means of transport. But for many migrant workers, bus lines remain their only option.

"We tried to get a train ticket, but there are too many people. All tickets were sold out before Chinese New Year. So we take the long-distance bus. We don't mind if it means more time on the road." Migrant worker Mr. Hu said.

As the Lunar New Year approaches, the road network will be carrying more students and migrant workers. This hub sends out over three thousand passengers every day now, but the number could climb to 6,000 a day.