Why so much algea bloom in the river

[toblerone]

:hoboy: I postponed plans to drift today cause I was told by a couple of folks that the river was clogged with algea making pulling plugs a bust and spinners a chore to keep working??? What is happening in a river system that makes this so thick right now. Water temp? Change of season?? Cow ****?? Any bioligist types can comment in plan english please??? Rain Rain pray for Rain........ :depressed:

John
Think Fish

[Keta]

high nutrient load + warm water temperatures + sun light = ALGAE

The nutrients could be coming from many sources. Farms or city runoff. Waste water
effluent from sewage plants or feed lots. :depressed:

How far upriver is this problem? Look upstream several miles and you might find the source. It is my opinon that it is both rural (cow), urban (people) and industrial efluent that is causing this problem. :mad:

[ 05-30-2002, 11:52 PM: Message edited by: Keta ]

[Small Fry]

I think you hit the nail on the head with all your choice's. But most of all water temp in combo with everything else is the cause.

Head for shifter water should clear up to some degree.

[Point-of-Sale Clerk]

The short answer for excess algal growth in most of our local river systems is high concentrations phosphorus derived from inorganic chemical fertilizers. Phosphorus in a river is present as a phosphate and not as elemental phosphorus. The phosphate monitored by DEQ for water quality is PO4. DEQ looks at two basic forms this phosphate manifests itself in a river’s ecosystem, that which is bound up in organic material (cells, fish tissue etc.) and free PO4. It is the free PO4 form that is the most quickly available for algal growth.

Unfortunately, DEQ does not easily distinguish the two types as one being good for a river and the other being bad. It is my opinion that ortho-phosphorus in the form of fixed PO4 is the single most important nutrient needed for our streams. Historically our streams were fertilized by the carcasses of spawning salmon and lamprey to the tune of several thousand pounds per river mile each year. This influx of Marine Derived Nutrients (MDN) is what made of river ecosystems so productive and robust. This slow release of fixed phosphorus was not harmful as opposed to the current loads of chemical wastes that make their way into our rivers. More sunlight and higher water temps are also part of the equation.

And yes, that was the short answer…
:grin:

[Jennie@ifish]

We have tons of algae this year, but also extremely low water conditions.
I can't think of much farming going on upriver of us, so I tend to believe it is low water and warm temps, mostly.
I've never seen it so thick.
This last rain, however, washed much of it away.
Jen

[OneLastCast]

Every year around the end of May or the beginning of June the North Fork of Nehalem experiences an algae bloom. It normally lasts about two weeks and then is gone. We don't usually have any problem later in the summer. The South Fork is another matter.

OneLastCast