There is an odd kind of music in this poem that creates interest: end rhyme, interior rhyme, and assonance. Wherever it occurs, it is unexpected and keeps the reader off balance. The experience of reading the poem is like drifting. It's quirky and very appealing.
The lines of this poem do drift in physical length, with the first being the longest and the last being the shortest. The sentences vary in length, with some words hanging on the ends of lines, creating off-rhymes and lines which almost rhyme into couplets ("rinse" and "since" come to mind). This creates a kind of rocking or drifting rhythm that is not consistent or soothing in effect. This, coupled with the water images--watering god, crying, blood, rinsing, a haunted lake--give the reader a sense that all is not well and the speaker of the poem is lost in more ways than one.
I've re-read this poem a few times and I find something new to like each time.