factors affecting water clarity MN

[DetectorGuy]

Now I don't want to implicate the farmers as my dad was one and I kinda have a hobby farm. I think poor clarity relates directly to the amount of fertilizer that was introduced to that body of water. Even citiots (sound it out...) have enough common sense to have the phrase "this runs to the the river" on their catch basins and manholes. I always figured farmers to be a good bit smarter than city folk but they missed the big picture for years when they continued to fertilize fields on the side of a hill where the fertilizer eventually runs into the creek at the bottom of the hill. This creek runs into the lake and the lake plants grow like mad. Even microscopic algae likes to eat this fertilizer and this is what we see in front of our masks when we get to the surface and tell our buddy "visibility sucks here, Why did you want to come here today?"

Now there are more farmers in the Southern and central Minnesota than in the North. I think you will find better water clarity where farmers aren't... This has the most to do with clarity in my humble opinion. the second thing that would affect clarity would be soil consistency that the body of water sits on. Third would be that amount of movement of that water (both natural movement and man-made movement). Fourth thing would be the amount of oxygen in the water that algae needs to grow. More algae = more oxygen produced by that algae (see the vicious circle forming here?) Fifth would be the season for that algae to grow (this would go hand-in-hand with water temperature.) The greener the lake is, the more the surface acts like a solar collector warming it up and accelerating growth.  The last thing that would affect clarity would be the source of that water directly. This would be a series of muddy tributary rivers or a series of subsurface springs.

Even though I haven't tried Ice Diving yet, I agree with Shooter that the best clarity in any spot would be under a sheet of ice. So this winter I hope to tag along with Shooter, A&A, and Arcflash on many of there ice dives...