Here ya go, Bwildly. A picture of the piping of your floor drain:
Now, notice that in the picture IT IS RAINING.
The rain percolates down through the ground to the bottom of the basement wall. There's weeping tile resting on the same concrete footing that the basement wall sits on.
The weeping tiles carry the water to a catch basin.(and that is a stupid looking catch basin)
(It'd be better to show that catch basin as rough concrete about the same diameter as the house's main drain line with a p-trap on the bottom. They've got it looking like a barrel with some kind of pipe on the bottom.)
There's a p-trap at the bottom of the catch basin, and then a pipe from that p-trap that connects to the main drain line from the house.
That pipe going up to the basement floor from the main drain line is supposed to be the vent stack.
The way they've got that drawn is kinda stupid. The vent stack should go below the basement floor, and then turn and go to the city sewer at a shallow downward angle. They've got it looking like the drain pipe from the catch basin flows at a shallow angle down to the sewer system and the vent stack connects to it. That's wrong. The vent stack turns under the basement floor and becomes the main drain line. The drain pipe from the catch basin connects to the main drain line somewhere under your basement floor.
You'd think that the City of Winnipeg would have run that drawing past a plumbing inspector just to check if there are any dumb things in it that need to be redrawn. Obviously they didn't.
Also, your house will have EITHER a sump pit with a sump pump OR a catch basin (aka: floor drain), not both. Both are shown in the diagram only because houses are built with both kinds of systems. Prior to 1990 in Winnipeg, houses with sump pits could have the sump pump pumping water directly into the house's drain piping so the water would join the water flow from toilets and sinks in the house.