Visualize historical trends

Select a Water Station and Substance to View Data Trends for the Past 20 Years (Data availability may vary).

Info Icon Station:
A "station" is a designated monitoring site used to collect data on water quality, quantity, and ecosystem health.

Watershed:
A "watershed" refers to a geographic area where all the water, whether from rainfall, snowmelt, or other sources, drains into a common outlet such as a river, lake, or ocean.

Note: Click the button below to export a consolidated report displaying trends for a specific station across all relevant substances/chemicals.




Generate Heat Map

Select a year and indicator to generate watershed level heat maps showing how water quality is expected to increase, decrease, or remain stable across watersheds and regions over time.

Select target indicator

DeX-Terity is an advanced web-based platform powered by machine learning that provides comprehensive insights into regional water quality. Users can view detailed watershed and water monitoring station-level data, visualize historical and future trends, and explore how changes, such as population growth or climate variability, may impact water quality. By integrating multiple data sources and analytical tools, DeX-Terity supports better policy, planning, and investment decisions.

How to use this tool?
Active Stations
Inactive Stations

Historical data and trends are derived from TRCA's Regional Watershed Monitoring Program (up to 2022) and CLOCA's Open Data (up to 2023).


Substance/Chemical

The Confidence Score, which ranges from 0% to 100%, indicates how reliable each model prediction is based on historical data and insights. It is calculated through a multi-step process, incorporating statistical analysis, feature importance, and machine learning predictions. Scores below 40% are considered Low, while scores above 70% are considered to be High. Higher scores indicate greater confidence in the model’s forecast, helping support informed decision-making and scenario analysis.

Threshold values for Total Phosphorus are based on PWQO water quality guidelines.
Applies to Rivers and Streams.

The Provincial Water Quality Objectives ( PWQO ) are Ontario’s water quality guidelines established to protect aquatic life, recreational water use, and drinking water sources. Developed by the Ontario Ministry of the Environment, Conservation and Parks (MECP), these objectives set concentration limits for various contaminants to maintain water quality and ecosystem health.

Low High

CSV file requirements

The CSV file must contain columns:

For Total Phosphorus (TP) prediction

Mandatory

  • pH
  • 250mLandCover_Natural (ha)
  • DissolvedOxygen (mg/L)
  • Population
  • Chloride (mg/L)
  • Nitrite (mg/L)
  • TotalSuspendedSolids (mg/L)
  • Nitrogen_Kjeldahl (mg/L)

Non-Mandatory

  • Total Rain (mm) -7day Total (mm)
  • Nitrate (mg/L)
  • TotalNitrogen (mg/L)

For Total Nitrogen (TN) prediction

Mandatory

  • Month
  • pH
  • 10mLandCover_Natural (ha)
  • 10mLandCover_AnthropogenicNatural (ha)
  • TotalSuspendedSolids (mg/L)
  • Conductivity (k)
  • TotalPhosphorus (mg/L)
  • Population
  • Chloride (mg/L)
  • Nitrite (mg/L)

For Total Suspended Solids (TSS) prediction

Mandatory

  • mwd_SEWAGE FLOW, MONTHLY TOTAL
  • min_distance_to_upstream_npri_meters
  • ThreeYearsAvg_DissolvedOxygen
  • PriorYear_Total number of farms
  • ThreeYearsAgo_IndsutryAgriculture
  • 10mLandCover_AnthropogenicNatural
  • ThreeYearsAvg_Number of Summerfallow land
  • PriorYear_MEAN_TEMP
  • ThreeYearsAvg_Conductivity
  • watershed_npri_count

Explore your watershed's vital signs

Map Icon

Map

  • Click on any highlighted region on the map to view detailed information about the corresponding watershed.
  • Click on the location markers to access specific details about water monitoring stations.
Trends Icon

Trends & Insights

  • Select a water monitoring station, and chemical/substance to view trends over the past 20 years for the chosen parameter at that location. Please note that data may be unavailable for some years.
  • Note: Click the button below to export a report displaying trends for a specific water monitoring station and substance/chemical.
Scenario Icon

Prediction & Scenario Modelling

  • Choose a water monitoring station and target indicator (Total Phosphorus, Total Nitrogen, or Total Suspended Solids) to view predicted trends for the next 20 years.
Scenario Icon

Watershed-Level Heat Maps

  • Select a year and indicator to generate heat maps showing how water quality is expected to increase, decrease, or remain stable across watersheds over time.
This website is best viewed on a desktop for full functionality. Some features may not be available on mobile devices.