Area lakes show good spring clarity
In the last three weeks, many lakes in Becker and Otter Tail counties have reported near-record water clarity readings. The water clarity is measured with a secchi disk, which is a white disk lowered into the water on a rope. The depth in feet that one can still see the disk in the water is the water clarity or secchi depth.
To name a few, Big Cormorant was 26 ft, Big Detroit was 20 ft, Ida was 19.5 ft, Otter Tail was 17 ft and Pelican was 20 ft. These lakes usually average 8-15 ft clarity throughout the summer. If you haven't measured water clarity on your lake yet this year I encourage you to go and do it as soon as you can. It is fun to measure such great clarity readings. This above average water clarity is good news of course, but it doesn't necessarily mean that water quality is improving overall. There are a few different factors that could be affecting water clarity this spring.
As you all know, the weather this spring has been atypical. With the cold temperatures our gardens and trees have been late to bloom. I've heard estimations that we're 2-3 weeks behind usual. Our lakes have been behind the usual schedule too, as lake water temperature continues to hover around 60 for most area lakes. This means that the aquatic plants and algae are behind usual, and there is just less production occurring in the lake. The clarity right now is closer to what we would expect for early May.
Another factor could be the lack of any large rainfall events. When an inch or more of rain falls in one day, the runoff from land washes nutrients into the lake and into streams that flow into lakes. This runoff can "feed" aquatic plants and algae. After the rain this week, we may start to see a change in our lakes.
It will be interesting to track the clarity in our lakes this summer. Depending on when (and if) we warm up, it could be an all around atypical year.
Until next week, enjoy the lakes!
Moriya Rufer is the Lakes
Monitoring Program Coordinator for RMB Environmental Laboratories in