This evening, as shown in the photos below, the water is a few feet from topping the embankment and spilling on to the road. As I write it may already be there. I don't know. But I did see a number of Metro Water Service employees on the road waiting for something. Not a sand bag in sight. You should be able to see the roofs of a couple of submerged sheds clearly below the road.
FEBRUARY 23, 2019 UPDATE: today's rain amount made this the wettest February in Nashville on record since 1880 (by the way, the wettest month on record in Nashville was May 2010). For the sake of comparison, look at photos from this afternoon in basically the same places along the Cumberland River Greenway.