According to the Ho Chi Minh City Department of Transport, the city currently manages more than 9.5 million vehicles, including more than 1 million cars and nearly 8.5 million motorbikes. If all of these vehicles were placed on the road, the area required would be double the current road surface area.
Each year, the number of vehicles increases by an average of 6.5%, while the road surface area increases by only 0.2%. In particular, in the inner city area, the road surface area has not expanded over the past 5 years.
According to the Ho Chi Minh City Planning for the 2021-2030 period, with a vision to 2050, recently approved by the Prime Minister, the city will develop a multifunctional underground space system.
This system not only serves transportation but also supports disaster prevention, climate change response and national security.
Ho Chi Minh City People's Committee stated that the central area cannot currently expand roads, while transportation demand is increasing.
If the development of elevated traffic will affect the urban landscape architecture. Therefore, utilizing underground space is considered the optimal solution to develop traffic infrastructure.
Ho Chi Minh City plans to build underground roads depending on the conditions of each area, such as: combining roads and electrical and information infrastructure; combining roads with railways; combining roads with urban drainage.
In particular, Ho Chi Minh City has determined to prioritize the construction of underground roads combined with urban drainage, due to the increasing flooding caused by rain and high tides in the city.
Ho Chi Minh City also plans to establish an underground space network linking urban railway stations with underground commercial spaces and access routes to buildings located in the area.
Notably, the city will propose a number of underground traffic routes such as: the route along the Saigon River through District 1, District 4 and District 7; the Ben Thanh station area and Ham Nghi street; the Bach Dang wharf area and Ton Duc Thang street; the area connecting Tan Son Nhat airport.
Ho Chi Minh City has consulted some effective tunnel models in the world.
In Wuhan, China, two road tunnels connecting Hankou and Wuchang districts are 4,660m long, with an outer diameter of 15.2m each.
The tunnel perfectly integrates a three-lane one-way expressway and a subway in one tube, greatly reducing traffic pressure across the Yangtze River. The two-way metro design under the six-lane expressway is only 40m wide, saving 120,000m² of land, reducing environmental impact, impact on residents and construction costs.
In Kuala Lumpur, Malaysia, the 9.7km long, 13m wide Smart Traffic and Flood Control Tunnel (SMART), completed in 2007 at a cost of $500 million, simultaneously solves flooding and traffic congestion problems.
This tunnel allows cars to travel one way per level, reducing travel time from the southern suburbs to the city center from 30 minutes to just 5 minutes. Notably, since SMART came into operation, Kuala Lumpur has not been flooded as before.
