Author(s)

C.-K. Hsiao & C.-C. Yang

Abstract

Using a DEA approach this paper assesses the performance of wastewater treatment from pig farms in Taiwan. The results indicate that most pig farms have decreasing returns to scale. The average value of scale efficiency for the sample of pig farms is 0.901, and the pure technical efficiency is 0.821. These efficiency values indicate that most pig farms may improve performance of wastewater treatment through the adjustment of control equipment scale and increasing wastewater treatment efficiency. Moreover, the main cause of scale inefficiency is decreasing returns to scale, which means that increasing investment in pollution control may not provide a corresponding increase of wastewater treatment efficiency. Based on the farm size, it is found that larger pig farms usually have higher values of efficiency. In addition to the farm size, other factors affecting the environmental efficiency are also analyzed and discussed. Keywords: pig farm, effluent regulation, environmental performance, data envelopment analysis (DEA). 1 Introduction The hog industry is Taiwan’s most important livestock industry. However, it is also the main cause of livestock water pollution. It is estimated that the daily quantity of biochemical oxygen demand (BOD) from wastewater is about 4,223 tons in Taiwan, and of this, livestock wastewater contributes 673 tons (16%) [1]. To regulate the water pollution caused by livestock industry, the Environmental Protection Administration (EPA) of Taiwan has implemented

Keywords

pig farm, effluent regulation, environmental performance, data envelopment analysis (DEA).