City of Moose Jaw dislodges ‘fatberg’ from pipe that serves half the city

The first clue that something was wrong was when a local business in Moose Jaw called to complain about a sewer backup on Monday.

So, Moose Jaw’s public works department sent someone out to investigate.

“Pretty quickly we saw we were getting a lot of surcharging (overflowing) happening along the trunk in the manholes, and knew that we were starting to see a several-block radius that was backing up, so we knew right away that we had a pretty major issue that had to be dealt with,” explained Darrin Stephanson, director of public works and utilities with the City of Moose Jaw.

After some finagling, crews found the blockage in one of the main sanitary trunks in the city – that’s a two-foot-wide pipe that sanitary lines for half the city empty into.

The blockage was what is known as a “fatberg,” a large deposit of hardened grease and fat along with sanitary products and wipes that collect and harden in the pipe.

Stephanson said it’s not uncommon for cities to see such things but this one was different because it was in such a large pipe.

“Typically we don’t see full blockages or near-full blockages that we saw in this occasion in those lines, so from that stance it was a bit unusual for us,” he said.

Over two to 2 1/2 hours on Monday, crews rerouted the pipes, dislodged the blockage with high-pressure spray, and then pulled it out with an HVAC system.

Stephanson said things like this happen when people put things down the drain or flush things that they shouldn’t be.

“An old practice most residents and even some businesses have (is) put grease and fat products down your sewer and you think you run it with hot water for 30 seconds or a minute that everything’s good. Unfortunately, all that grease has to go somewhere,” said Stephanson.

He explained the grease goes into the sewer and then starts to solidify as its temperature drops and starts collecting on anything it can that doesn’t have a smooth surface.

“And once you get a buildup starting to occur, well, then it just starts grabbing everything else,” Stephanson said.

The crews are going to be doing some more scouring of the pipe and investigating to make sure everything is gone and see if any changes need to be made to maintenance practices.

The blockage happened near Third Avenue NE and Manitoba Street. Stephanson explained it happened near the entrance to a siphon which moves the sewer underneath the river.