Since the 1940s, the Waibaidu Bridge has undergone four major repairs and reinforcements, including the most recent one in 1999. By 1947, after 40 years of service, the municipal government did a check that revealed weakness in the structure and a tendency to sink into the ground (12.7 cm since 1907). In June 1947, a private company was contracted to reinforce the structure and prevent further sinking. No other major work was done thereafter, except the widening of the walkways for pedestrians after 1949.