Provincial Water Quality Monitoring Network (PWQMN)

The Provincial (Stream) Water Quality Monitoring Network (PWQMN) measures water quality in rivers and streams across Ontario. Over 400 locations are currently monitored in partnership with Ontario's Conservation Authorities, Severn Sound Environmental Association, and other agencies. . Partners collect water samples on an approximately monthly basis and deliver them to the Ministry's laboratory where they are analyzed for a suite of water quality constituents. The program has been operating since 1964 providing a valuable database for tracking changes in water quality over time. More recently, special studies have been implemented in agricultural and urban watersheds to collect additional information in support of source protection planning and nutrient, road salts and pesticides management.

This dataset on DataStream is an integrated version of the original source dataset (see source URL). The data have been reformatted, and PWQMN fields and vocabulary have been translated into DataStream’s standardized structure. Certain fields, such as result value detection limit and activity type, have been derived from combinations of source field values. Refer to DataStream’s result comment field for more detail about source code values.

While most records are included, some records that are not compatible with DataStream’s schema (e.g. records with missing coordinates, records with stream condition measurements etc. ) are excluded. Additionally, adding records with new PWQMN parameters to this dataset may be delayed as DataStream’s schema may need to be updated. For the most complete and up-to-date version of the dataset, users should refer to the original source (see source URL). Please reach out to the PWQMN and DataStream team if you want to learn more about how the data is mapped between the two systems.