Abstract:
Some Ecological Factors Affecting the Input and Population Levels of Total
and Faecal Coliforms and Salmonella in Twelve Mile Creek, Lake Ontario and
Sewage Waters Near St. Catharines, Ontario. Supervisor: Dr. M. Helder.
The present study was undertaken to investigate the role of some
ecological factors on sewage-Dorne bacteria in waters near St. Catharines,
Ontario. Total and faecal coliform levels and the presence of Salmonella
were monitored for a period of a year along with determination of temperature,
pH, dissolved oxygen, total dissolved solids, nitrate N, total phosphate
P and ammonium N. Bacteriological tests for coliform analysis were
done according to APHA Standard Methods by the membrane filtration technique.
The grab sampling technique was employed for all sampling.
Four sample sites were chosen in the Port Dalhousie beach area to
determine what bacteriological or physical relationship the sites had to
each other. The sample sites chosen were the sewage inflow to and the
effluent from the St. Catharines (Port Dalhousie) Pollution Control Plant,
Twelve Mile Creek below the sewage outfall and Lake Ontario at the Lakeside
Park beach. The sewage outfall was located in Twelve Mile Creek, approximately
80 meters from the creek junction with the beach and piers on Lake
Ontario. Twelve Mile Creek normally carried a large volume of water from
the WeIland Canal which was diverted through the DeCew Generating Station
located on the Niagara Escarpment. An additional sample site, which was
thought to be free of industrial wastes, was chosen at Twenty Mile Creek,
also in the Niagara Region of Ontarioo
3
There were marked variations in bacterial numbers at each site and
between each site, but trends to lower_numbers were noted from the sewage
inflow to Lake Ontario. Better correlations were noted between total
and faecal coliform population levels and total phosphate P and ammonium
N in Twenty Mile Creek. Other correlations were observed for other sample
stations, however, these results also appeared to be random in nature.
Salmonella isolations occurred more frequently during the winter and spring
months when water temperatures were minimal at all sample stations except
the sewage inflow. The frequency of Salmonella isolations appeared to be
related to increased levels of total and faecal coli forms in the sewage
effluent. However, no clear relationships were established in the other
sample stations. Due to the presence of Salmonella and high levels of
total and faecal coliform indicator organisms, the sanitary quality of Lake
Ontario and Twelve Mile Creek at the sample sites seemed to be impaired over
the major portion of the study period.
