"What Am I?"
It's strong, and powerful, and sometimes unreliable, but its beauty is undeniable.
It tumbles and bubbles, and babbles away, and is occasionally known to gleam in the day.
It's shallow and clear, and generates reflections, and often times splits in different directions.
It flows, and it slows, and its density grows, but it never once stops, unless it snows.
What am I?