The Water Survey of Canada is a branch of Environment Canada which provides comprehensive flow or surface water level data for rivers across Canada. For each hydrometric station, one can query daily or monthly flow or water level rates for the years that the station was active. Some stations only have records for a few years, while others have records for over 80 consecutive years. Some stations also have records for sediment loads and concentrations.
The data are not provided in any geospatial format, but there is an interactive Google Map interface which shows the location of currently active stations. The metadata document also contains the latitude-longitude coordinates for each station. The data can be viewed in an graphical format, which can calculate basic statistics about the data range (e.g. calculate the mean flow rate of a river over the course of a whole year). The data can be viewed tabular format in the web browser, and can also be exported in .csv format, which can be exported into Microsoft Excel.