James - I haven't personally viewed any algae blooms in my area, but the colors in your photo look dead-on similar to the Mother of all blooms that smothered the lake in 2010. Let's hope we're not headed down that path.
Just a few weeks ago we celebrated a huge event..... for the first time in 12 years testing for microcystins, the toxin from our "normal" GLSM algae, showed the toxin levels were "undetectable". Never happened before and water clarity had been incredibly clear for months.
Quietly, many of us were jubilant but leery there could be another shoe to drop. Why the apprehension? You see, in 2010-2011 when the lake blew up, the scientific wizards from Battelle Institute were engaged to analyze what happened, why the historic algae bloom happened. After months of studies Battelle reported the lake actually contained multiple strains of algae. For unknown reasons, in 2010 the normally dominant algae did not thrive, became recessive and in its absence another normally recessive strain thrived and dominated. That strain gave us the thick 2010 algae that looked like paint in white, blues, and turquoise swirls.
The abnormal water clarity this year and recent test data shows our "normal" algae is not present in normal levels. If you follow the logic I'm pushing, is the door open for a recessive algae strain to become dominant and thrive as history shows happened a decade + ago?
Before anyone jumps off the deep end, keep in mind GLSM is not the same lake as in 2010. Conditions are different. The loading of nitrates and phosphates to feed algae is different, so we're told. The southside tributaries now have treatment trains to filter contaminants which is another difference. Tons and tons of dredged materials with legacy contaminates are gone, another difference.
Clearly current photos and reports tell us something is going on. The next few weeks should tell us if we've done the right things and enough of them over the last 11 years. Cross your fingers!