The city said Thuong Nhat Company had submitted a feasibility study and plan, which includes details on several routes.

But all remains on paper, Tran The Ky, head of the city’s Department of Transport, was quoted as saying by the Sai Gon Giai Phong (Liberated Sai Gon) newspaper.

Many local residents and city authorities have supported the idea and asked investors for their input, but obstacles, such as low bridge clearances and the shallow levels of canals, have deterred other potential investors.

The city has even asked State-owned enterprises to invest in the project, but they have shown no interest.

Nguyen Kim Toan, director of Thuong Nhat Company, said such a system could increase tourism and reduce traffic congestion on the roads.

However, many of the city’s canals and rivers are too shallow to carry passenger boats and the clearance of many bridges is too low.

The city has more than 230 bridges over rivers and canals, many of which do not meet the standard of 2.5m of clearance required under the city People’s Committee’s water-traffic zoning plan through 2020.

According to the city’s Transport Department, the Nhieu Loc – Thi Nghe Canal alone has 20 bridges with very low clearance.

A representative from Thuong Nhat Company who declined to be named said one major problem was the need for land clearance to build 16 ports for the water-bus system.

Ky, the transport department head, said that some bridges would have to be rebuilt, which would increase construction costs.

These kind of costs were scaring away investors, who were worried about not making a profit.

In its plan, the Thuong Nhat Company said it would use boats of different sizes to adapt to the condition of canals and the navigation of some bridges.

The company’s plans called for a 25km waterway route stretching from District 12’s An Loc to Nha Be District’s Phu Xuan, and a second 12km route from Ben Nghe Canal to Tau Hu Canal.

Other routes would extend to western and southern areas, including Ca Mau, Kien Giang and Ha Tien, Dong Nai and Binh Duong.

With a dense system of rivers and canals, nearly 8,000km in length and a water surface covering 16 per cent of the total space, HCM City would be an ideal place to have a waterway bus system, according to city officials.

Under Thuong Nhat’s plan, 16 boats would be used, eight of which would be able to carry 100 passengers per trip, and the remaining, 40 passengers.