Each watershed score is determined based on four key freshwater health indicators: water quality, hydrology, benthic invertebrates, and fish populations. Scores are assigned using a standardized methodology that evaluates data availability, trends, and exceedances of environmental thresholds. If data for a given indicator is missing or insufficient, the watershed may be classified as “Data Deficient” rather than receiving a full score​.

Watershed scores are based on the best available data we could access and include, but gaps in monitoring can lead to incomplete assessments. If you believe a score does not reflect local conditions, it may be due to missing data, historical inconsistencies, or differences in methodology that were incompatible with the Freshwater Health Assessment. Remember also that we only looked at data from streams and rivers, not lakes, estuaries, or ocean water. We encourage communities, researchers, and organizations to share additional data with us to help improve future assessments​

Not directly. While the 2025 Watershed Reports build on WWF-Canada’s previous assessments (2017 and 2020), several major changes make direct comparisons difficult:

• Watershed Boundaries: We transitioned from WWF-Canada’s Pearse watershed boundaries (used in 2017 and 2020) to the Standard Drainage Area Classification (SDAC) framework, meaning watershed groupings for scores differ.

• Scoring Methodology Updates: We refined how water quality exceedances are weighted, adjusted how data sufficiency is classified.

• “Not Scored” for Northern and Central Benthic Zones: Unlike WWF-Canada, we opted not to score benthic invertebrate data in regions where existing tolerance values and reference conditions are unreliable. This ensures more scientifically defensible assessments but means past scores for these areas aren’t comparable.

• No Threats Assessment: WWF-Canada’s reports included an assessment of threats (such as pollution, habitat loss, and climate change) in 2017, though this was not updated in 2020. Water Rangers chose not to include a threats assessment in 2025, instead prioritizing improvements to the Freshwater Health Assessment and addressing known data deficiencies.

• Improved understanding and classification of data deficiency: Rather than just identifying data-deficient sub-watersheds, the 2025 reports take a more detailed approach to understanding why data is missing. This includes assessing historical data availability, barriers to access, and structural gaps in monitoring programs. Some sub-watersheds previously scored in WWF-Canada’s reports are now classified as “Not Scored” if the available data did not meet updated sufficiency criteria or if scoring method is not appropriate for that region.

Because of these significant methodological changes, direct comparisons between WWF-Canada’s Watershed Reports and the 2025 assessments are not recommended. However, both reports provide valuable insights into freshwater health and highlight the ongoing need for better data and long-term monitoring. 

You can access the WWF-Canada reports here.

ndividuals and organizations can contribute by supporting community-based monitoring programs, advocating for stronger water policies, and engaging in conservation efforts. Open-data platforms like DataStream and CABIN enable public participation in data collection and transparency, helping to fill critical knowledge gaps and inform decision-making. 

Visit our take action page for ideas and opportunities.

A “Data Deficient” classification means there was not enough publicly available, high-quality data to assess freshwater health in that watershed. This reflects challenges in water monitoring, such as historical data loss, lack of standardized reporting, and gaps in long-term monitoring programs. Addressing data deficiencies requires investment in open-data initiatives, community-based monitoring, and improved collaboration between government, industry, and researchers​.

Many regions in Canada lack sufficient freshwater data due to historical gaps, limited monitoring programs, and challenges in data accessibility. Some data may exist but remain unavailable due to paywalls, outdated formats, or fragmented storage across different agencies. In remote areas, logistical and funding constraints have also contributed to limited monitoring.

To improve data availability, we need sustained investment in long-term monitoring, better collaboration between governments, researchers, and community groups, and open-data initiatives like DataStream and CABIN. Individuals can help by supporting local water monitoring programs, advocating for stronger policies, and contributing to community science efforts.