Ok... After enlarging the photo about sixteen times, I believe this thing is a mobile, possibly inflatable, pump platform, not a submarine and CERTAINLY not Russian.
The thing on top that could be mistaken for a sub conning tower is a pump engine, running at time of photo, and liquid is being pumped into the scream. There is a mooring line at the “stern” going toward the break in the scrub brush on the right side of the photo. Toward the bow is a round port that can be opened to fill an internal tank with liquid, waste, etc. It could probably also be used to siphon water from the stream and pump it through a hose for irrigation.
Not a submarine, and almost certainly not Russian. These guys just want a tiny bit of public fame....
If... If, it was russian, my first question would be where did it fuel up along the way without being seen??