While Barlow's piece doesn't precisely follow the classical model (because of its lack of rebuttal), she constructs a strong structure here in defense of her claim. Note how she follows point (or grounds) after point (or grounds) with continually infused information to support the claim and specific topic per paragraph. Again, where this deviates from the traditional model is in its lack of rebuttal (concession and refutation of the most likely objection to her claim which would be: we are not running out of water).
Per the Rogerian model, Bibas identifies two clear opposing sides. He looks at the the most likely objection/rebuttal/concession to incarceration practices/perspectives (addressing the liberal or left viewpoint). Once he analyzes these and pinpoints logical errors in that approach, he moves onto the other side--the conservative or right-leaning viewpoint. Here, he analyzes the conservatives' arguments and shows the weaknesses of them. In conclusion, he points out the flaws in both sides and aims to arrive at a solution.
Note the classical style here: Pollitt looks first at the likely objections to her claim (the concessions/rebuttals) and then systemically refutes each one. Following, she addresses other key points in support of her claim and then ends on the toughest of rebuttals to her claim which she also refutes.