This study analyzed the virtual water flows within 65 major US cities based on commodity flow data to estimate each city's water footprint. The researchers found that on average, cities produce 30% of their domestic water footprint within their boundaries and import the remaining 70% from other domestic locations. There was large variation between cities, with some being net consumers and others net producers. The majority of cities were net consumers due to the strong dominance of agricultural commodities in their water footprint and limited productive land area within city boundaries.