What did the water tower symbolise in What is eating Gilbert Grape?

Answer 1

Arnie is mentally disabled and cannot care for himself. Anytime Gilbert's back is turned Arnie climbs the water tower. The significance is that it shows that Gilbert is unable to have his own life and care for Gilbert on his own because it usually happens when he's making deliveries for work or trying to talk to a friend. To Arnie, climbing the water tower is like a way to prove he can do something he's told he isn't able to.