Northern Avenue Bridge

The Northern Avenue Bridge closed

years ago to motor traffic.

Pedestrians still cross unless

the red light blinks and the swing

span opens for water craft

on Fort Point Channel. Rusty

steelwork casts elaborate shadows

on the weed-trimmed deck. I pause

at the west end and note the swing

span open although no boats appear.

The channel looks deep enough

to float a cruise ship. If I dropped

from here I’d sink so far the flesh

would peel from the bone before

I ever touched bottom. Long ago,

bicycling over this bridge, I saw

two kids diving into the dark,

splashing like seals, laughing off

the threat of drowning and shouts

of the bridge-keeper whose shack

still clung to one abutment

reached by a long wooden stair.

That shack collapsed in a storm

at least forty years ago

and lingered as a ruin for two

more decades before slipping

forever into the dark. The shadows

cast by the girders look strong

enough to support real traffic

again, but the city engineers

in their finite wisdom declared

the weight-bearing impossible,

and for a long time considered

the swing span inoperable

and so propped it open for good.

Now it works again but only

for sloggers like me who prefer

their city travel slow and certain,

and who like to tempt ourselves

by crossing unsure dimensions

with all of our senses tingling

as shadow and light intersect.