Fig 2. The mean of Enterobacteriaceae cell counts from Tsomo and Tyhume rivers.

Ts1 and Ts2 are sampling points along the Tsomo river, while T1 –T4 are sampling points along the Tyhume river. Using the Welch and Brown-Forsythe robust tests of equality of means, the mean counts were statistically significant at P ≤0.05 and F = 256.59. The statistics were asymptotically F distributed.