Sub-Basin Valuation of Agriculture: A Crop-Specific Assessment of Groundwater Footprints and Value in California
California's agricultural sector supports a global food chain. This industry is enabled
by a vast network of surface water supplies and stressed groundwater resources, which
enable year-round irrigation of water-intensive crops such as pistachios, almonds, and
rice. Due to the 2007-2009 and 2012-2016 droughts, there has been renewed interest in
statewide groundwater management, ... read moreculminating in the 2014 Sustainable Groundwater
Management Act (SGMA). However, the nexus of agricultural water consumption of specific
crops and their spatially explicit economic value remains unexplored. Openly accessible
data for these outcomes are not centrally stored, are spatially and temporally
disparate, and have not yet been synthesized for a critical analysis of the groundwater
footprint of agriculture in the state. We derive a unique dataset of the estimated
economic value of groundwater and surface water used for irrigation, at the county,
basin, and sub-basin scales. For the study period of 2007-2017, we synthesize remote
sensing, spatial, and tabular data on crop identity, water footprints, and economic
value. This synthesis allows us to study trends in crop water consumption, drought
resilience responses, and value impacts. A case study of the Delta-Mendota sub-basin
provides further insight into historical trends in agricultural groundwater consumption,
crop portfolios, and crop switching practices during drought and recovery periods. This
dataset can help various stakeholders weigh the economic and environmental costs and
benefits of crop- and basin-level groundwater management decisions. It is also expected
to improve the current methodology used to prioritize groundwater basins for
conservation, and thus inform long-term goals set by basin-level Groundwater
Sustainability Agencies under SGMA.
Thesis (M.S.)--Tufts University, 2018.
Submitted to the Dept. of Civil Engineering.
Advisor: Elena Naumova.
Committee: Sumeeta Srinivasan, and Magaly Koch.
Keywords: Water resources management, Environmental engineering, and Agriculture engineering.read less