What does the tidal lane on the highway mean?

[MacBarrett]

Tidal lanes are identical in appearance to regular lanes but feature the added functionality of changing flow direction based on morning and evening rush hour variations. Below are detailed explanations of tidal lanes: 1. Purpose: In traffic flow management renovations, variable lanes are implemented as a method of traffic organization. Tidal lanes are essentially variable lanes where, based on differing traffic volumes during morning and evening commutes, eligible roads are equipped with one or multiple lanes whose permitted travel directions change according to the time of day. 2. Operational Method: During morning rush hours when inbound traffic is heavier, the number of inbound lanes is increased while outbound lanes are reduced. Conversely, during evening rush hours with heavier outbound traffic, outbound lanes are increased while inbound lanes are decreased.

[DeJune]

The tidal flow lanes on highways are quite practical! As a daily cross-city commuter, during the morning rush hour, it's obvious that the inbound direction is heavily congested. At this time, the tidal flow lane temporarily converts one outbound lane into an inbound lane. We just need to follow the arrows on the LED signs above the lanes, and when the green light is on, we can proceed. During the evening rush hour, the adjustment is reversed. This kind of intelligent traffic flow management is quite common on highways in big cities like Shenzhen and Shanghai, reducing congestion time by about 30%. However, it's important to pay attention to the real-time indicator lights. Last week, my colleague almost got penalized because he was looking down at his phone and mistakenly entered an unactivated tidal flow lane. During peak hours, map navigation apps usually provide advance notifications about the status of tidal flow lanes.

[MacLukas]

During my internship at the traffic management bureau, I researched this design. Tidal lanes essentially address one-way peak traffic flow by dynamically allocating lane resources. For instance, during morning rush hours when inbound traffic surges on the Beijing-Hong Kong-Macao Expressway, the system borrows 1-2 lanes from the outbound direction, using retractable barriers and electronic signage to switch directions. The biggest advantage is increasing traffic capacity by 40% without road expansion, but drivers need to adapt to real-time rule changes. Usage may be suspended during rainy seasons or heavy fog – drivers must immediately vacate the lane when they see the X-shaped red light overhead. Some expressways also adjust speed camera enforcement zones in coordination with tidal lane operations.

[Imogen]

From the perspective of road engineers, tidal flow lanes are the product of dual optimization in space and time. The core principle is utilizing idle resources from opposing lanes: during morning rush hours when eastbound traffic accounts for 70%, one westbound lane is borrowed; the operation is reversed during evening rush hours. Implementation methods include not only electronic signage but also movable barriers or dual-row traffic lights—red lights on the inner row indicate prohibited travel, while green lights show the currently permitted direction. The most critical period to be cautious about is the transition phase; when yellow lights flash five minutes before the switch, do not enter hastily. For example, the Qiantang River Bridge tidal flow lane in Hangzhou can accommodate an additional 2,000 vehicles during peak hours.