EPA Water Quality Exchange (WQX)
Universal water quality data format
epa.gov
At a glance
- Region
- United States
- Coverage
- 1500+ agencies contributing
- Access
- Free
- Category
- Government
- Last updated
- 2025
What's inside
- Standardized Data
- Multi-Agency
- Quality Assured
What you can do with it
Typical work that data of this type supports.
- 01
Hotspots and trends
Find where contamination is high and whether it is getting worse.
Because it has: Quality Assured
- 02
Compliance checks
Compare samples against drinking water and discharge standards.
- 03
Sampling plans
Decide where to sample and treat first.
Where AI adds value
Ideas for machine learning and AI agents built on this kind of data.
- 01
Risk maps
Predict contamination where no samples exist, from geology, land use and climate.
- 02
Anomaly alerts
Catch sudden spikes in sensor or lab data automatically.
- 03
From satellite
Estimate turbidity and chlorophyll in lakes and rivers from imagery.
Machine access and documentation
Open API
Machine-readable endpoint on waterqualitydata.us
Licence: US Government public domain
Listed in our registry of open water APIs, which WaterDataGPT can query live.
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- NOAA Atlas 14 Precipitation FrequencyUnited States | Free
- US Drought Monitor (USDM)United States | Free
- US Water Quality Portal (WQP)United States | Free
Find more water data
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