Several extreme events affecting recreation have occurred in the Humboldt River Basin of northern Nevada. In 1992, agricultural users completely drained Rye Patch Reservoir killing millions of fish. Additionally, since 1990 gold mines located in the basin have pumped and discharged water into the Humboldt River; in recent years, discharges have equaled approximately 60% of the river's annual flow. In this paper we develop and estimate a joint model of fish catch and recreation demand, both of which depend on water levels, to assess the losses and gains from water level changes tied to events in the basin. ¿ 1999 American Geophysical Union