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Water Chemistry Monitoring


Water chemistry volunteers measure phosphorus levels, chlorophyll-A concentrations (a measure of algae growth in the water), water clarity, and a temperature profile from the top to the bottom of the lake. This type of monitoring is done four times per year, and requires several hours of time during each monitoring event. Chemistry monitoring helps determine if nutrient pollution is occurring in a lake, or if seasonal fish die-offs may be a possibility due to low oxygen levels. 

Water Chemistry How-to Video

Want to know more about water chemistry monitoring? Want a little refresher after the winter months to make sure you collect and report accurate data?

Check out this great how-to video!

Water Chemistry Training Resources

Chemistry Procedures

Water Chemistry Monitoring Forms

Secchi and Chemistry monitoring form​ (3200-099)

Use this form to submit temperature and dissolved oxygen profiles along with Secchi depth.

For a list of ALL monitoring forms, click here (exit UWEX Lakes)

Water Chemistry Resources


*NEW* Interpretive Guide to CLMN Annual Reports​

Use this short guide to interpret the data that is included in your lake's annual reports.

How do I calibrate my dissolved oxygen meter or replace the sensor/membrane? 

YSI has produced instructional videos on how to do these maintenance tasks with three of their popular dissolved oxygen meters. Click on any of the topics below to watch the videos.

YSI Pro20 meter - how to calibrate the meter

YSI Pro20 meter - how to replace the sensor

YSI 550A meter - how to calibrate the meter

YSI 550A meter - how to replace the membrane

YSI ProDSS meter - multiple maintenance videos

Dissolved Oxygen Calibration Log

Hach HQ30D Dissolved Oxygen Meter Instructions & Calibration Guide

YSI ProODO and ProSOLO Instructions & Calibration Guide

Understanding Lake Data​ (A guide to interpreting lake data)

This guide was written to help people understand information about lake water quality and to interpret lake data. Each lake possesses a unique “personality,” or set of physical and chemical characteristics which may change over time. Lakes exhibit chemical changes on a daily basis while other changes, such as plant and algae growth, occur seasonally. A glossary of technical terms is included to help the reader understand the language used in the study of lakes (limnology). ​

What else can volunteers monitor?



For more information contact
Paul Skawinski, Citizen Lake Monitoring Network Educator
(715) 346-4853
Or go to
The Wisconsin Department of Natural Resources site
at (exit UWEX Lakes)​​​​​​
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