As of February 1, 2008, the U.S. Board on Geographic Names had identified 5,564 natural streams in the State of Colorado.  Of this number, 147 larger streams (2.6%) were named river and 11 (0.2%) were named rio.  The vast majority of the Colorado streams (5082 or 91.3%) were named stream.  Of the remaining Colorado streams, 122 (2.2%) were named arroyo (creek), 60 (1.1%) were named wash (creek), 44 (0.8%) were named stream, 18 (0.3%) were named stream, 17 (0.3%) were named stream, 17 (0.3%) were named stream, 15 (0.3%) were named stream, 10 (0.2%) were named River delta, but not a single stream was named stream.  Perhaps the strangest stream name in Colorado belongs to the West Fork East Fork Williams Fork located in Garfield County, Colorado.. Which name was the least common for natural streams in Colorado?