There's a string of reasons why only some lines are underground

Seattle Post-Intelligencer

Le, Phuong Cat

Newspaper

02/20/2007

D1, D3

"Of the roughly 2,500 miles of power lines in the city of Seattle, only about 660 miles, or 26 percent, currently runs underground. There are 20 or so neighborhoods where some of the lines were paid for by local improvement districts....In preparation for the 1962 World's Fair, the City Council wanted to 'move unsightly wires' around the Seattle Center and over the freeway...."

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