I was wondering what sources are available, or if anyone has GIS water quality data for the Great Lakes and specifically Lake Ontario?

We are interested in mapping Phosphorus, Organic Matter, Nitrogen and Dissolved Oxygen concentrations in Lake Ontario as they relate to algal blooms and hypoxia.

2 Answers 2


The only data I could find on some of these parameters is from http://ontario.ca's 'Provincial (Stream) Water Quality Monitoring Network' which can be accessed at http://www.ontario.ca/environment-and-energy/provincial-stream-water-quality-monitoring-network .

The raw data is available from http://www.ontario.ca/environment-and-energy/provincial-stream-water-quality-monitoring-network-pwqmn-data in MS Access, Shapefile, and MS Excel formats where each row represents a sensor readings which include the following sensor descriptions:


Hope this helps!

  • Thanks for the reference, I appreciate the help. This will do the job we need it to do. Appreciated Jul 28, 2014 at 14:42
  • @JasonIgras Don't forget to click the green accept checkmark if this is the answer that helped you the most.
    – PolyGeo
    Oct 14, 2018 at 8:43

Here are some results for US data:
National Water Quality Monitoring (US)
EPA EnviroAtlas
Nitrogen and Phosphorus Pollution Data Downloads
National Lakes Assessment (US)
National Aquatic Resource Surveys (US)

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.