Foam in Creek

[DrRod]

Greetings,

Just came in from a short walk around the place and noticed a large pile of thick off-white foam piled up against a log in the creek. This is common especially after a rainy period. I have always wondered what causes this. Is it natural, agricultural runoff, or soap from houses upstream?

 

[4570Man]

I have also seen this. Like you said it usually occurs after a hard rain and not under normal water flow. I have no idea what causes it.

 

[treefarmerguy]

I believe it's caused by water being churned up while containing a lot of dust, pollen, ect. The same thing happens at the shore during a coastal storm. It can be quite interesting to see the amount of foam that can be generated

 

[murphy1244]

Some times its phosphorus from fertilizers.

 

[DFB]

I get the same phenomenon in seasonal runoff swale I built on my land to control the water. When I originally noticed it I first thought maybe a neighbor had an overflowing gray water dry well or septic lagoon. Nobody is supposed to have stuff like that around here.

Now I figure it is more like a natural occurrence caused maybe by turbulence. My little swale is torrent for a day or so after a heavy rain.

May just be a mix of air and water along with some organic decomposition

 

[4570Man]

I went outside to look for foam. I found a few small patches, but I have seen much larger patches.

 

[oosik]

The foam is usually organic material either caused by a storm on the ocean, stirring up organic sediments, or by additional/heavy runoff into a river or stream. There can be other causes but this would be the most common natural situation.

 

[PILOON]

We also get greenish foam after higher winds.
Generally accepted to be pollen that is churned by the wind creating foam.

 

[MossRoad]

Our local river foams in great amount fairly often. There are sometimes thousands of pillow-sized piles of it floating along downstream of the dam, where it gets churned up. They've never really determined what exactly causes it, but they say it is of no health concern.... move along, citizen... :laughing:

 

[Fossil Farm]

It can be lots of things, both natural and/or from manmade items. Naturally decomposing organic matter, especially from wetland areas can create a foam or "oil slick" haze on the water. Phosphorous and anhydrous fertilizers can also cause foaming in turbulent waters of a stream. No real visual differences. Have to do a water test to find out. Unless you see dead aquatic life and a nasty smell, probably nothing to worry about.