Against the tide

Amidst the mists of the valley,
the roar of the motorway
the haze of the newly risen sun,
the river was at flood tide
and flowing upstream.

Fifteen miles from the coast
the current was strong,
forcing the river against its nature;
flowing upstream.

I only see it once or twice a month [usually consectutive days], but each time it is amazing and transforms the Parrott from a muddy trickle to a powerful river.
And as with running through pitch black woods, there is a certain parallel with the rollacoaster ride of learning to teach.