When should we measure lake levels?

By Grant Parkins

Jul 20, 2017

An example of a lake gauge

That is a question we get asked a lot by volunteers who care about their lake, and who want to be sure that we are getting the data we need to help better understand them. Like with many questions, there is both a short answer and a long answer.

The short answer is… Anytime! Each measurement we receive helps us better understand these lakes, so we can never have too may measurements.

There is a long answer to that question as well, though. To study these lakes, we are using two types of data: 1) Lake height measurements submitted by citizen scientists, and 2) Lake surface area measurements calculated from satellite images. We are using images from the Landsat 8 satellite, which passes over our study lakes periodically, and we want to have lake height measurements on the same day that the satellite passes overhead.

Target Dates

For this reason, we also have a list of Target Dates when we encourage citizen scientists to submit lake height measurements. These target dates occur every 7-9 days, and lake height measurements taken on these days are useful in very specific ways. If we have lake height measurements on the same days we are able to get lake surface area measurements from satellite images, then we can know how the volume of water in these lakes is changing. In addition, if we have lake height measurements from all lakes in an area on the same day, then we will be better able to compare lakes to each other. We can understand, for instance, if all the lakes in a region are affected by rainfall or drought in the same way.

For more information on how to take lake height measurements, including what to do when there are waves, visit our Get Involved page.

Upcoming Target Dates