Lyric discussion by oliverthered 

I think Underneath the bridge The tarp has sprung a leak

is literally, a bridge over troubled water.

and if you listen to the song that fits musically too, as the ending is in stark contrast to the first part of the song, and somewhat violent.

also

The album's title refers to the Wishkah River in Aberdeen, Washington, where Cobain claimed to have spent nights sleeping under the Young Street Bridge as a teenager (as referenced in the song "Something in the Way," from the band's 1991 release, Nevermind). This claim has since been refuted by Novoselic, who said, "He never lived under that bridge. He hung out there, but you couldn't live on those muddy banks, with the tide coming up and down. That was his own revisionism."[

@oliverthered he was a story teller. I dare say one day whilst "hanging out" under the bridge he imagined what life would be like there, perhaps even felt living under the bridge was a great metaphor for where his life was at that stage.

@oliverthered if he’s under a bridge how/why does the tarp leak?

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