Data sources

For the 2025 Watershed Reports, Water Rangers compiled 33.8 million data points from hundreds of sources to assess freshwater health across four key metrics: hydrology, water quality, benthic invertebrates, and fish populations.

314

Data providers

33.8 million

Datapoints

>700

Datasets
View full list (google drive)

Where does the data come From?

Water quality datasets

Water quality was evaluated using 416 datasets, 67.8% of which were sourced from DataStream, with community science groups contributing 60.6% of all datasets. We’re also happy to share that Water Rangers groups, through our integration with DataStream, contributed 26% of the datasets!

Water quality sources

Flow datasets

Hydrology data came exclusively from HYDAT, Canada’s national hydrometric database, with over 12.6 million data points from more than 8,000 stations. While we found some other incredible hydrological datasets (Columbia Water Hub, Skeena), we weren’t able to integrate it for this version of the report. Read more about other sources on our Resources page.

Invertebrate datasets

Benthic invertebrate data, drawn primarily from CABIN and regional programs, included 578,271 data points. Conservation Authorities from Ontario made up a large proportion of accessed datasets.

Invertebrate data sources

Fish datasets

Fish population data came from 263 sources, with the most coming through private consultants and databases like Flowing Water Information System (FWIS). They totaled 658,746 data points.

Fish data sources

Champions and challenges

Despite the sheer volume of data, significant gaps remain. Across Canada, 72% of major watersheds and 75.6% of sub-watersheds were classified as data deficient—lacking enough reliable, long-term, or accessible data to assess freshwater health. These gaps stem from fragmented data systems, limited monitoring, and inaccessible historical records. Many valuable datasets remain undigitized or scattered across agencies, while others are locked behind paywalls or lack essential metadata, making them difficult to integrate.

Open data platforms such as DataStream (water quality) and the Columbia Basin Water Hub (water quality and hydrology), CABIN (benthic invertebrates), FWIS (fish) and HYDAT (hydrology) have made significant strides in centralizing and standardizing water data, helping bridge accessibility gaps. However, addressing the broader data deficiency challenge will require greater collaboration, improved data management practices, and more transparent sharing of monitoring results across sectors.

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