This report reviews the Alberta Health Records and the literature concerning the incidence of microbiological, viral and protozoan waterborne diseases in the Northern River Basins Study area. From this review the report concluded:
1. The potential risk from microbial contaminants can be high in comparison to the potential risk from chemical contaminants.
2. For many pathogenic microbes there are substantial non-human reservoirs. As a result, even complete elimination ofhuman discharges will not eliminate the source for many pathogens.
3. Little data is available in the Northern River Basins Study area to assess microbial water quality. There appears to be a need to increase the baseline microbiological data on surface water quality in the study area for microorganisms other than those currently required by Alberta Environmental Protection.
4. Analysis of health records showed that there appeared to be a trend towards higher incidence of giardiasis, salmonellosis and shigellosis in some of the health units, but failed to indicate if this was due to foodbome, person to person or waterborne means of transmission.
5. Results also indicated that although incidence of some diseases were higher in many cases, the differences were not significant and residents do not appear to have substantially higher risk from waterborne disease in the study area compared to the rest of Alberta.
The analysis of health records is an essential first step in setting up a framework for assessing the risks to health from microbes in drinking water in the study area.