Philip Louis Pratley

2 March 2017

Known as the “father” of the Jacques Cartier Bridge, engineer Philip Louis Pratley spent from 1925 to 1930 designing the plans for this structure that is now regarded as a symbol of Montreal. Pratley earned an enviable reputation in engineering thanks to his innovative mathematical approach to structural design and analysis.

Did you know that when the Jacques Cartier Bridge was built, it was one of the longest cantilever bridges in the world?

Born in Liverpool, England, Pratley earned an honour’s degree in civil engineering structures and received the William Rathbone Medal given to the best students in engineering.

After immigrating to Canada, he got a job in 1906 as a designer-draftsman at the Dominion Bridge Company in Montreal. He worked for this well-regarded firm until 1920. In 1909, at the age of just 25, he was given an important role in the design of the Quebec Bridge to replace the one that had tragically collapsed two years earlier. When it opened in 1917, this bridge was the longest in the world!

In 1921, Pratley started a private consulting firm and partnered with Lieutenant-Colonel Charles Nicholas Monsarrat  to form the Montreal civil engineering firm Monsarrat  & Pratley. This firm oversaw the construction of the Jacques Cartier Bridge and other major structures in Canada and the United States.

PHO Philip Louis Pratley

The Jacques Cartier Bridge is the first bridge that these business partners worked on together. Pratley was responsible for the full design of the structure spanning over 1.6 km. After its construction between 1925 and 1930, the Jacques Cartier Bridge was the fifth longest cantilever bridge in the world. With five lanes, it was also recognized in 1937 as the most modern wide bridge of its category.

Since 1987, the Canadian Society for Civil Engineering has awarded the P.L. Pratley Award  to the engineer who has written the best technical paper on bridge engineering.