Champagne Papi just shared footage of the scene inside his massive estate, and there's brown liquid flowing through what appears to be a walk-in closet area.

It looks like Drake's got a member of his house staff trying to keep a door closed to protect some of his wardrobe ... while he's walking through the watery mess with a broom, which definitely seems useless at this stage of flooding.

The rapper's seemingly maintaining a good attitude about it all, despite the frustrating situation ... joking about the brownish water, "This better be Espresso Martini."

Large sections of Toronto are under water right now on the heels of 3 huge storms that have left citizens stranded and without power.

Drake, by all accounts, does have power still, despite the intense flooding ... and nothing about this looks pleasant.

Toronto got almost 4 inches of rain just on Tuesday, breaking a more than 80 year old record.

Drake's mansion has been through a lot these past few months -- as we reported, there was a drive-by shooting and a string of alleged trespassers in the immediate wake of his Kendrick Lamar feud.

Drizzy's mansion is reportedly worth north of $100 million, and it's got 50,000 sq. ft ... so, lots of space for that floodwater to flow.