Bacterial Quality of Recycled Wastewater Used for Flushing Holding Pens

In a study at the Clemson University LaMaster Dairy Center we examined the bacterial quality of recycled wastewater used to flush holding pens.Two 11,400liter tanks were used, one containing recycled wastewater and another containing chlorinated city water. Each tank was used to flush a holding lot housing approximately 20 cows. Water samples were obtained from each holding tank and from three equidistant points along the flow of the flush water. Swabbings were collected at each of the three sampling points in each pen after water had drained. Each sample was cultured and enumerated for total coliforms, Escbericbia coli, Enterobacter sp., Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus sp., klebsiella, pseudomonas, and salmonella. All bacteria observed were in significantly greater numbers in the holding tanks of recycled wastewater as opposed to chlorinated city water. Only Staphylococcus aureus was in greater numbers in flushed, recycled wastewater than flushed, chlorinated city water. Few differences in bacteria counts were observed on surfaces flushed with recycled wastewater and with chlorinated city water.