This is a setting of Psalm 137 and coincidentally comes up in a couple of weeks (4th week of Lent Year B). It is by Paul A. Tate and has a singable refrain for the assembly and good verses for the cantors to proclaim.
You can hear a snippet, read the text in the sample pages and buy the sheet music at WLP. You can hear the whole song here with all its harmonies. If you are using the guitar edition of Voices As One like me, there are chords missing on the bottom line of the second page of the music – G(add2) & E/G#.