To trace the contamination and evaluate the environmental impact of piggeries, the occurrence of norfloxacin (NOR), ciprofloxacin (CIPRO), enrofloxacin (ENRO) and sarafloxacin (SARA) residues were evaluated in water for swine consumption, piggeries' wastewaters, drainage waters and a river receiving piggery effluents. Water samples were acidified before being percolated through Oasis HLB cartridges or through a tandem system consisting of strong anion-exchange and Oasis HLB cartridges. A liquid chromatography with fluorescence detection (LC-FD) method developed in previous studies, based on the use of a monolithic column, was successfully applied. NOR, CIPRO, ENRO and SARA had good linear responses, with mean regression coefficients higher than 0.9989. The limits of quantification (LOQ) for waters for swine consumption, and a river receiving piggery effluents, were 0.025 ug L(-1) for NOR, CIPRO and ENRO and 0.05 ug L(-1) for SARA. For wastewaters and drainage waters, the LOQs were 0.05 ug L(-1) for CIPRO and ENRO and 0.1 ug L(-1) for SARA. Recoveries obtained for spiked samples ranged from 70.8 to 89.1%, and precision data were under 12.7%. The method was successfully applied to 18 environmental water samples, collected from piggeries in Alentejo, Portugal, and the first Portuguese data are presented. ENRO was detected in a total of 8 samples, at concentrations ranging between 0.31 microg L(-1) and 63 microg L(-1). CIPRO, its degradation product, and SARA were present in 2 samples, in the ranges 0.48-0.83 microg L(-1) and 1.8-14 microg L(-1), respectively. No fluoroquinolones were detected in the waters for swine consumption or in the river water samples.