A characterization of large-scale swine production and manure generation in Virginia counties and cities located within or outside of the Chesapeake Bay Watershed

Economies of communities in the Chesapeake Bay watershed depend on commercial and recreational fishing, but various pollutants threaten plants and animals native to the region. Agriculture is the largest source of nutrients and sediment entering the Bay. Mathematical models employed to predict the quantity and fate of nutrients entering the Bay from the various land uses determine success in reducing pollutants. Sources of accurate livestock production data allows development of valid decision support tools including models. Livestock populations used in models reflect census data collected every five years by the USDA. The USDA cannot disclose information allowing a reader to determine information for individual farms. Thus, data for some counties within the Bay watershed often are not reported skewing results. The objective of this study was to characterize swine numbers and manure nutrient generation in Virginia and to begin building a database that can facilitate creating mathematical models used by various groups as decision-making tools.