Bill Williams River - Confluence of Big Sandy and Santa Maria rivers to Alamo Lake COA
Bill Williams River is a high priority water. No native fish are present in the river, but northern Mexican gartersnakes were captured in 2012. This was a completely new population and the first time the species had been seen within the Lower Colorado River drainage since 1904. This is one of three known populations in the Bill Williams Drainage. Largemouth bass, bluegill, and channel catfish occur in the river and allow opportunities for sport fishing where access can be found.