One of the first steps taken to improve environmental conditions was to cover part of the Little River by building Sainte-Anne Market and the sewer running beneath it, between 1832 and 1834. The river’s course had to be diverted—probably when its water level was at its lowest in summer—to build the sewer as well as the market’s foundations. It appears that a natural meander was used to make the work easier.

When the sewer was built in 1832, it was nothing more than an underground river, but it was soon put to use as a main line, with a large number of secondary sewers connected to it to carry wastewater away from Montréal households. People were beginning to understand that moving wastewater out of inhabited areas was essential to maintaining a healthy way of life. The collector remained in use until 1989!

This survey plan of 1832 shows the route of the sewer laid out along the course of the Petite rivière. It also includes, on the left, the plan of Sainte-Anne Market. The document was attached to the contract for filling in the valley and levelling the ground after the sewer was built.