Spring Clarity

Was your lake water clarity lower than usual this May?  Many lakes in northern Minnesota experienced this.  It is most likely because of the late ice-out and/or the rainy last few weeks.

cloudywaterWhen the ice goes off the lake in the spring, the lake turns over (see article on lake stratification and mixing).  When the lake turns over, the water becomes cloudy and the nutrients that mix up from the bottom can feed algae blooms.  Usually spring turnover happens in late April or early May, but this year with the late ice out spring turnover occurred in late May.

In addition to the late ice out, we received 2-6 inches of rain in late May and early June.  This rain could have caused runoff and erosion, which can also make the lake cloudy.

This week, lake clarity should be very good because the lakes have started to stratify, and we’ve had a dry week.