Impacts of Water Scarcity and Climate on Land Use for Irrigated Agriculture in the U.S. West Coast

In this article, we use the most comprehensive data on irrigated agricultural production in the United States – the USDA Farm and Ranch Irrigation Survey (FRIS) – to assess the effects of water scarcity and climate on land use decisions for producers of specialty crops, wheat, and forage crops. The data is used to estimate a land use decision model for major crops in the West Coast (California, Oregon and Washington), which includes a farm-level equation of harvested acres and crop-specific equations of harvested acres (orchard/vineyard, vegetable, wheat, alfalfa, hay, and pasture). The analysis leads to several interesting findings, some of which have been identified previously in the literature and others which are novel. First, producers harvest fewer acres in response to deeper well depths. Producers’ response to well depth is driven by a reduction in land allocated to pasture. Second, producers that receive surface water from a federal agency or that use surface water only have lower average water costs and allocate more land to pasture than other crops. Third, producers harvest more land if irrigation is used to mitigate frost damage to orchards and vineyards. Fourth, producers respond to drought by increasing land allocation to orchards and vineyards and reducing land allocation to alfalfa and hay.