Survival of faecal coliforms and faecal streptococci, with special emphasis onStreptococcus bovis, in soil and drainage water held at 5#xB0;, 10#xB0;, 15#xB0;, and 20#xB0;c under laboratory conditions was studied by membrane filtration techniques. In drainage water number of coliforms had increased by more than 100 after 48 h at all temperatures, but number of faecal streptococci had fallen, particularly at 20#xB0;c. at which the number had dropped by 80. There was no clear pattern of coliform survival in effluent-irrigated soil; the general trend was a decrease at 5#xB0;, 10#xB0;, and 15#xB0;c up to 4 days, but an increase of 30 at 20#xB0;c. Similarly, iaecal streptococci had decreased by the fourth day at 5#xB0;, 10#xB0;, and 15#xB0;c and by 300 at 20#xB0;c. 5.bovisrepresented 60 of all isolates from the drainage water and only 6 from the effluent-irrigated soil. Sixty percent of theS. bovisisolates survived for 7 days at 10#xB0;c in the drainage water. The low level of 5.bovisrecorded in the soil may be due to the unsuitability of the membrane filtration technique for soil samples. An alternative method should be developed as soon as possible.
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