TABLE 1. Naturally occurring generic E. coli populations in filtered creek water and water collected from a rain barrel Replication Water sourcea Filtered creek 1 Rain barrel Filtered creek 2 Rain barrel Filtered creek 3 Rain barrel aWater was collected from sources in Kansas. bThree subsamples of each water type were enumerated using Colilert Quanti-Tray/2000 for each replication. cGeneric E. coli not detected is indicated as <1 MPN/100 ml. Subsampleb 1 2 3 1 2 3 1 2 3 1 2 3 1 2 3 1 2 3 E. coli (log MPN/100 ml)c 1.3 1.2 1.2 <1 <1 <1 2.3 2.2 2.3 <1 <1 <1 1.8 1.8 2.0 <1 <1 <1 Mean E. coli (log MPN/100 ml) 1.2 0.0 2.2 0.0 1.9 0.0 TABLE 2. Physical parameters of sand-filtered creek and rain barrel water collected from sources in Kansas Replicationa 1 2 3 Water source Filtered creek Rain barrel Filtered creek Rain barrel Filtered creek Rain barrel Mean pHb 8.3 (0.01) 7.0 (0.05) 8.1 (0.02) 6.9 (0.09) 8.2 (0.02) 6.9 (0.02) Mean electrical conductivity (µS/cm) 716.0 (12.77) 120.9 (4.42) 464.3 (7.51) 241.2 (270.90)c 509.5 (10.02) 66.1 (6.79) * Mean turbidity (NTU) 2.3 (0.13) 0.5 (0.01) 5.0 (0.23) 0.8 (0.09) 4.5 (0.07) 1.1 (0.13) aFor each replication, three subsamples were analyzed for pH, electrical conductivity, turbidity, and TDS. bThe average of each parameter is reported for each replication. The standard deviation of each mean is provided in parentheses. cResults from replication 2 differed substantially from those of replications 1 and 3, resulting in a large standard deviation. Mean TDS (mg/ml) 397.3 (33.56) 52.3 (3.06) 422.3 (71.32) 180.7 (236.13)c 488.0 (2.08) 53.7 (2.89) * 362 Food Protection Trends September/October