Dave Bonta's poem begins with a question that sounds almost like a small, private shock: what wing broke a pinion in the garden? A pinion is the outer part of a bird's wing, so we picture something hurt and fallen among the plants. The poem doesn't say what bird it was, or whether the speaker has actually seen it. That uncertainty is part of the mood.
The second part turns to the speaker. They are "hunting a word," something that might carry "us" through "the long waters." The "us" is left open, so it could mean the speaker and a companion, or all of us. The rainy season of the title seems to be flooding the world, and the phrase "on each side the east" hints at being hemmed in, with water stretching away in every direction. What the speaker feels is a quiet need: for comfort, for language that can help in a time of damage and endless wet. The mood is hushed, searching and a little sorrowful, but the hunt for the word suggests hope.