 Under natural conditions, the San Juan River supported native fishes including Colorado pikeminnow, razorback sucker and roundtail chub, but these have been largely been eliminated in favor of rainbow trout, non-native (introduced) brown trout and other salmonids which thrive in the cold water released from the base of Navajo Dam.The San Juan is designated a Blue Ribbon fishery and is one of the most popular fly-fishing waters in the western United States.After a federal biological assessment in 1999, the San Juan River Basin Recovery Implementation Program (SJRIP) was established in order to help recover native fish populations in the river.