1. Water-surface profile and flood boundaries for the computed 100-year flood, Porcupine Creek, Fort Peck Indian Reservation and adjacent area, Montana Yale Public content 1993. 2002-06-01T04:00:00Z. 2014-03-21T19:31:45Z. Geological Survey (U.S.). The Survey ; Copies can be purchased from Books and Open-File Reports Section. English. Public. Montana, Fort Peck Indian Reservation, Valley County, and Porcupine Creek.