This poem, written in five sections of free verse, begins with the speaker remembering the old steel bridge he used to drive over on his way to work. He describes how the gaps between the steel beams had given him access to the world beyond the bridge: he had been able to see the river bank and railroad tracks and, most importantly, the people down there, "wild dangerous men" living near the edge of the river.

The poet next describes the new bridge, with its smooth speedy surface and solid concrete sides concealing the view. He then steps back and reflects: "what now?" He compares the engineer making the bridge with his own writing, "diminish[ing] the homeless to a poetic abstraction," and asks where this leaves him. Both bridge and abstraction, he implies, take the life, untidy and dangerous but valuable, out of his experience of crossing the Missouri.

He cannot view the material for his poetry now, unless he were to stop, back up the traffic, and risk his life climbing the walls of the bridge, and even then he does not know what he would say, because the new bridge has made him realize something about himself: "I am partly the leech come to feed, / yet I cannot waver from my groove." As a poet, he needs access to the lives of others, an access he likens to parasitism. But his career, the work to which he is going, requires him to speed on across the bridge without pausing.

He now elaborates on his distance from the world of the homeless people (and, by implication, all the other material for his poetry), saying that he has "safely bled away the guilt, / and pity and compassion," from his involvement or complicity in the meaning of his material, and "channeled it" into the poem. The leech image is now applied to the poem which, once filled with those ambivalent emotions, becomes separate from the poet and attaches itself instead to the reader, who now becomes the one feeding on the "dark spurt of old blood," the horrifying riches of which the speaker has rid himself.