Its pure waters maintain an outstanding forage base that has promoted Merritt to become of one the top trophy fisheries. Maximum depth is 111 feet with an average depth of 25 feet.
Water levels are stable, except during summer irrigation season when they drop.
Water Source - An impoundment of the Snake River completed in 1964 by the Bureau of Reclamation. Boardman Creek is the only significant tributary. Primary water uses are irrigation and recreation. Water - Fertile with varying clarity. Heavy summer algae blooms greatly reduce clarity, but Secchi disk readings of 6 feet have been recorded in spring.