How Saigon's Notre Dame Cathedral Narrowly Escaped Being the 'Leaning Cathedral'

Shortly after its completion, Saigon's iconic Notre Dame Cathedral developed an embarrassing tilt. Built between 1877 and 1879, the cathedral was constructed over a large underground aquifer discovered during foundation work. While this aquifer provided a much-needed water supply for the city, it created significant problems for the builders. The sandy soil caused one of the towers to sink, disrupting the cathedral's symmetry and earning it the nickname 'Leaning Cathedral of Saigon.'

Urgent remedial work was undertaken to prevent further subsidence, but the tilt could not be fully corrected. In 1892, it was decided to add two cast iron spires at a cost of 66,500 francs. The construction, overseen by engineer M. Michelin, began on December 26, 1894, and was completed on February 28, 1895. The spires were designed as 27-meter-high octagonal pyramids with skylights for ventilation. The western spire was made slightly taller than the eastern one to restore symmetry.

Although the addition of the spires largely solved the leaning problem, some claimed that the height difference between the two towers remained visible, especially from the top of rue Catinat (modern Đồng Khởi Street). Over time, the cathedral became a symbol of the city and continues to attract tourists and locals alike.

The cathedral's construction also addressed Saigon's water crisis. The underground aquifer discovered in 1877 was used to supply drinking water to residents. The first water tower was built at the junction of rue Sohier and rue Catinat prolongée (modern Turtle Lake roundabout), distributing water through underground conduits. This water source proved inexhaustible, providing a reliable supply even during the dry season.

In conclusion, Saigon's Notre Dame Cathedral is not only an architectural marvel but also a testament to overcoming engineering challenges. The leaning issue was resolved through innovative solutions, and the cathedral now stands as a historic and cultural landmark. According to Tim Doling's research, the structure holds great significance in Vietnam's heritage.