Despite appearances, water begins to run low in Chester's Mills on Under the Dome. "The Endless Thirst" is the sixth episode of the show's first season.
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Under the Dome Season 1 Episode 6 Quotes

Julia: Honestly I"m a little scared. What happens when we run out of everything. What do we do then?
Barbie: I don't know.

Barbie: These people. These people are scared.
Linda: To tell you the truth, so am I.