The bacteriological self-help survey for recreational lakes



Hendry, G. S.

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Ontario Ministry of the Environment


Eighteen lakes in Southern Ontario were examined for bacteriological water quality with the assistance of cottager associations. This self-help program ran from 1971 to 1975 inclusive. The results showed that lake water quality was generally good, but low levels of contamination were noted, mainly at inflowing streams. Where the possibility of contamination of human origin arose, marinas, trailer parks, and river mouths were implicated. Higher levels of total coliforms were isolated in lakes of higher trophic status as measured by Chlorophyll a (Chl a) levels. This relationship was expressed as a regression of total coliforms on Chl a so that: LOG10 TC (Summer) = 0.77 + 2.23 LOG 10 Chl a (R = 0.7242). The bacteriological self-help program was useful in screening levels of pollution in lakes, and in responding to requests for lake surveys from cottagers, and it is recommended that it continue in Regions of Ontario which have the required laboratory facilities, and that, whenever possible, it be carried out with the trophic status self-help program (secchi-disc/ (Chl a).


Ontario Ministry of the Environment
Biological Surveys/Investigations Reports


water quality, contamination, bacteria, coliforms, chlorophyll, trophic status, bacteriological water quality, recreational lake