Under the old system, drivers often waited at red lights despite no oncoming traffic, or sat through green lights with no movement on the opposite side. The new adaptive system detects traffic volumes in real time and adjusts each cycle accordingly — extending greens when queues grow, shortening them when roads are clear, and cutting unnecessary delays. The 74 upgraded intersections cover major congestion-prone corridors, including Sukhumvit, Rama IV, Phahon Yothin, Ramkhamhaeng, Sathorn, Silom, Rama IX and Ploenchit. Of these, 168 have no traffic lights, while 578 are controlled by traffic signals. Among the signalised intersections, 433 operate on a fixed‑time system with preset cycles, and 71 use an older adaptive loop‑detector system.

Source: Bangkok Post February 26, 2026 22:07 UTC