Protecting water quality - Environmental monitoring and problem mitigation
The City operates and maintains a network of rainfall gauges. The information is used to determine sewer sizes and the influence/impact of storms of various sizes on the existing sewer system and on streams (floods).
The City collects and analyses water samples from sewers, at sewer outfalls, in stream and at the lakefront for a variety of management reasons. For example, lake water sample results are used to determine the suitability of the water for swimming; sample results from sewers and at sewer outlets are used to determine, trace and to correct the discharge of prohibited pollutants to our sewer systems.
An example of prohibited pollutant is the discharge of sanitary sewage to a storm sewer because the sewer drains were installed/hooked up incorrectly (commonly referred to as a cross-connection). When this occurs, raw sanitation is discharged to the lake or stream via storm sewers. When monitoring and investigation reveal such occurrences, the owner of the cross-connection is requested to correct the problem.
The City does not routinely patrol its stream catchbasins. It often depends on the public to be its 'eyes' in observing contaminants in stream or entering catchbasins. When such incidences are reported (call 311 to report illegal dumping or spills), city staff will trace the source of the contaminant, and ensure the situation is corrected and does not recur.