Three coliphages (FRNA, FDNA and somatic) and three bacterial indicato
rs (faecal coliforms, Escherichia coli and enterococci) were measured
in four waste-treatment lagoons over 10 months. Two of the lagoons tre
ated domestic sewage; the third, meat processing waste and the fourth,
meat processing waste with a minor sewage component. In the meat proc
essing lagoons the ratios of FRNA:FDNA were numerically large, due to
very low counts of FDNA, and somatic coliphages generally outnumbered
FRNA. Many of the FDNA plaques from meat processing lagoons were very
small and were not confirmed on the F-plus strain, E. coli C 3000. In
sewage lagoons all three coliphages were consistently present and FRNA
usually outnumbered both FDNA and somatic coliphages. However, the ra
tios of FRNA to the other two coliphages were not numerically large. R
atios of coliphages, especially of FRNA:FDNA, seem a promising tool to
distinguish between human and animal faecal pollution. Overall, there
were no strong correlations between the bacterial indicators and the
coliphages.