PNNL

Abstract

This paper discusses the estimated impact of climate warming on water availability for instream flow in the Yakima Valley of Washington State. Current state law and regulation provides for minimum flows to sustain anadromous and resident fish and to maintain water quality, but climatic change could significantly change the flow regime of the Yakima. In addition, there would be an uncertain, but probably significant, shift in the demand for water by irrigated crops grown in the valley.This paper provides an initial assessment of the impact on instream flow in the Yakima Valley of shifted water demand for irrigation for a climate warming at today's concentration of CO2 and at 560 ppm.