Do federal farm policies influence surface water quality?

Federal government farm payments authorized by the Farm Bill accounted for 32% of the total U.S. net farm income in 2005. This study uses Census of Agriculture and nitrate-nitrogen (NN) data to ask whether there is a quantifiable relationship between the allocation of these farm payments and indicators of surface water quality using 29 independent watersheds covering 28% of the conterminous U.S. The analysis identifies a significant relationship between increasing government farm payments and: (1) increasing riverine NN concentrations, (2) more expansive fertilizer applications, (3) commodity specialization, and (4) reductions in cropland diversity. These results suggest that federal farm policies could be an important factor affecting water quality, and the authors present a working hypothesis that farm policies influence land use decisions that, in turn, ultimately influence water quality. These farm payments, subsequently, could be used as a potent policy instrument to influence alternative environmental and economic outcomes that protect soil and water resources.