Well, firstly quite a few joggers jog with someone else, who can help out if any difficulty occurs.
However, more to the point is that the OP has a sealed-cockpit kayak. If he's using a spraydeck and is alone, then I hope he can roll, and roll proficiently. And that he wears a helmet.
If he's using a spraydeck, gets into trouble and capsizes he could hit his head, knock himself out for a few seconds. Or even just simply panic, and forget how to get out of the boat when upside down.
Basically, he's trapped underwater and could well drown, as there's no-one else to assist.
It's good safety to never paddle alone.
Also, no-one on a riverbank is likely to bat an eyelid at an upturned kayak, they'll probably think its' floated downstream from somewhere. Its near impossible to tell that there's a person still in it when its' upside down.