"Water, water every where, and all the boards did shrink; water, water, every where, nor any drop to drink," the poet Samuel Taylor Coleridge wrote in the "Ryme of the Ancient Mariner" in 1798. And that's an apt description of tonight's Hell on Wheels 3.7 taking place less than a hundred years later - including the shrinking of the board that was attempting to railroad Bohannan out of the railroad last week.

The water is undrinkable because it's carrying cholera.  And the pursuit of potable water (for some reason, I like that word) by Bohanan is the main spring of the story tonight.   He finally reaches it, thanks to the son of the Mormon couple murdered by the Swede last week.

I was glad to see this, not only because it saved Bohannan and the railroad, but because it connected Bohannan, at long last, to the Swede.  I'll be disappointed if Bohannan doesn't put the Swede out of his misery by the end of this season.

Back to the shrinking board:  it shrunk by one in tonight's episode, because Durant shot the Senator who not only failed to deliver Bohannan on a platter last week but was now extricating himself from being Durant's lacky.  Durant is getting more reckless by the episode, now shooting a U.S. Senator point blank dead.

But the most powerful storyline in tonight's episode had little to do with water - except insofar as Eva didn't want her daughter subjected to the daily deadly perils of life on the frontier, such as cholera. So she gives her and Elam's baby to the baby's biological uncle.  Elam - as we see in the coming attractions, and as makes total sense - will go ballistic when he finds out.   Indeed, it's hard to see how his relationship with Eva can survive - unless, perhaps, she is pregnant, this time with his child.

But the irony regarding the bad water and cholera theme of tonight's episode is they had plenty of that back here in New York, back then, too.