One expanation for the abundant green algae in our rivers

[Dick G]

Last night I heard a guy talking about water quality in Illinois ponds and lakes and he had some interesting things to say about the prevalent algae that has appeared in our rivers the last few years. He said that because of the drought the last 2 years, the soil has an abundance of nitrogen in it. The crops and lawns were stressed and did not take as much nitrogen from the soil as usual. Fertilizer was used in the normal amounts. The more concentrated nitrogen levels worked their way into lakes and rivers and led to a spike in algae growth. This year with expected normal rainfall amounts (that's what farm forecasters are predicting) the rivers and lakes should flush out and we should see a lot less algae this year. Of course all of this excess fertilizer runoff will end up in the Gulf of Mexico. Down at Lake Sara in Effingham, there is a tremendous amount of algae this year. I have never seen it look like this before. Even casting a spinner bait in some areas required cleaning off the slime after every retrieve. In the last few days the algae has already started to diminish. I hope the same thing happens to our streams in Illinois. I probably don't have the scientific explanation down correctly, but this is the gist of what I heard from a water quality-erosion expert speaking before the Effingham Water Authority.

[Kev-mo]

You can't discount the role of light/clarity. You won't get much synthesis w/out the photo part. The springs with more rainfall sure puts a dent into both the algae and weed production on the Dupe. Not saying there isn't extra nitrogen available...

[Dana Lee]

All my lakes are choked with veggies.

[ronk]

That algae along with unnaturally dense weed growth in rivers & lakes doesn't depend on the amount of rainfall.It depends only on urban sprawl & does just fine in both wet & dry years.Get used to it.

PS

When you get to the heart of it there is only one thing at the core of our planet's environmental problems-there are just too damn many of us crawling around on it.

[mlahart]

The nitrogen abundance sounds reasonable. We also had less ice, hence more light getting through, especially on the rivers. And no good winter scouring of the rivers by flood waters and ice(remember all the news about not having enough water to float barges on the Mississippi). And an unusually warm December and January; I spent a lot of time cleaning algae off decoys in Kankakee. The algae would normally be out of the river by mid-December.

[joshw]

I have heard that the boom in geese (increased loads of goose waste!)using ponds, lakes and rivers has added to the amount of algea growth especially in most ponds. I know most I fish are loaded with them and cormorants. I sadly see very few mallards using them anymore. Add these factors to the low water and heavy use of nitogen rich fertilizers and you have a perfect envirionment for huge algea growth.

[joshw]

Here is something I recently read: "Canadian Geese in flight can be majestic, grand, and inspiring. It’s when they get down on land that another problem appears… goose poop. Waterfowl, according to some studies, can produce 25% to 34% of the total phosphorous budget in a watershed. And phosphorous is what we need to control around the Three Lakes in order to control weeds and algae." "Left unchecked, their population will double every 5 years. While feeding, geese defecate every 7 minutes. Each goose produces 1 to 3 pounds of waste per day. In addition to phosphorous, they contribute pathogens such as e coli and the bacteria that cause swimmer’s itch, as well as giardia, cryptosporidium, and campylobacter. Geese are one vector for the spread of invasive plants such as milfoil and water chestnut." Now if we could just get rid of all the non migratory geese, ban use of fertilizer use on watershed areas as well as drainage our only problem would be low water!

[Ryan Kral]

This is a really interesting article, a little outdated. But to go along with the Nitrates theory, we had some late season snow, and some decent rains, which are the two main contributors in nitrates(nutrients for plant life) being deposited in the rivers. The reason why spring has the most algae growth. Ryan

http://illinois.sierraclub.org/news/Restoring_Dupage.pdf