Recently, an article asserted that the main cause of traffic jams in major cities is not vehicles but the insufficient road network and ineffective traffic management. I agree completely with this viewpoint.
The increasing trend of car ownership in our society is an inevitable outcome of modernization. Eventually, every household and individual will own cars, while the prevalence of motorbikes in urban areas will naturally decrease.
Take Hanoi as a prime example of inadequate infrastructure. In the 1980s, Thanh Xuan Bac and its surrounding areas, currently part of Thanh Xuan District, were largely undeveloped. At that time, the city's master plan included a fully grade-separated intersection at Nguyen Trai and Khuat Duy Tien, which would allow vehicles to move freely in all directions without traffic signals.
However, due to poor coordination among authorities, many residential projects were built, reducing the available space for this intersection. As a result, the Nguyen Trai - Khuat Duy Tien intersection was only partially completed and has since become notorious for frequent congestion.
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Traffic congestion on Nguyen Street Street in Hanoi in January 2025. Photo by VnExpress/Pham Chieu |
The current design includes some overpasses for straight lanes but still relies heavily on traffic lights for turning and additional straight lanes. Traffic lights only manage traffic effectively up to a certain density; exceeding this threshold worsens congestion.
Moreover, improper timing of traffic signals can further exacerbate congestion. The Nguyen Trai - Khuat Duy Tien intersection currently surpasses this threshold, particularly in the Khuat Duy Tien - Nguyen Xien direction, causing chronic congestion.
Other significant intersections, such as Nga Tu So, Dao Tan - Lieu Giai, Lang - Cau Giay, and Hoang Quoc Viet - Xuan Tao, also face similar issues, with partial overpasses combined with traffic lights for turning vehicles, contributing to rush-hour jams.
Therefore, I recommend that bridge and road construction agencies lead collaborative efforts to establish new projects, design, and build additional overpass lanes for straight-moving vehicles. Additionally, constructing clothoid-shaped (spiral-shaped) overpasses for seamless left turns should be seriously considered wherever feasible.
Some might argue that inner-city areas lack space for these clothoid overpasses. However, it's unnecessary to demand large areas. We can realistically design useful curved bridges which require minimal space. Additionally, referencing successful international designs could help develop practical clothoid overpasses in Hanoi and other major Vietnamese cities, significantly alleviating traffic congestion.