They didn't plan to use seawater, when it was obviously available.
The obvious question, though, is what did they plan for? It's the same question we were asking Texas during the big winter freeze of 2021.
They were planning for the climate to be as it always has been, when it's clear that the climate is changing for the more extreme.
This highlights my frustration with the politics of the climate change issue. The climate is, indeed changing, but the high-level federal political debate is on whether humans started--and can reverse--climate change while nobody is discussing what states and localities should be doing to endure the changing climate. At this point, the balance may have tipped beyond the point that humans can pull it back, and it's clear that there is not the global political will necessary to pull it back (it looks like we'd have to take global technology back to the pre-agricultural stage).