Technical Abstract: Freshwater eutrophication, a threat to water quality in many parts of the world, is accelerated by increased inputs of phosphorus (P), of which agricultural runoff is a major contributor. During the last decade in Brazil, there has been a 33% increase in the number of livestock, with most in the South (i.e., Parana, Rio Grande do Sul, and Santa Catarina), where 50% of Brazil’s swine and poultry production is now located. We estimate 2.5 million tonnes of P in swine and poultry manure were produced in 2003, mostly in the South (62%), which represents only 18% of Brazil’s land area. In 2003, 1.08 million tonnes of P were produced in manure with 0.42 million tonnes applied as fertilizer in the South region, amounting to a regional annual P surplus of 0.66 million tonnes. Unless measures are implemented to address P surpluses, the potential exists for increasing water quality degradation.