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Apart slip dress, collier de chien belt, silk scarf, Chanel bag, and Madden Girl gold ruffle sandals (all own)

Have you ever wondered about the white foam that forms on the beach where heavy waves break in response to the first storms of fall? Or have you ever wondered about foam on river banks or lakes? thispost reveals what that foam is all about. And you’ll be surprised!

  1. Healthy Alaska rivers have foam
  2. Foam is made up from lipid molecules of decay
  3. Clean-up
  4. How can you to distinguish natural from anthropogenic foam?
  5. Color varies depending on uptake of material
  6. Outfit of the day

Disclosure: There are affiliate links in this post.

Healthy Alaska rivers have foam

Standing at Grael’s landing, I overheard many tourists over the years being upset about the “pollution” on the river. They were referring to small spots of foam on the water. Sometimes even 5 cent size dots of foam float downstream in summer.

When you kayak or canoe or travel on Alaska rivers or go fishing at Alaska rivers or lakes, you often see foam on river banks, or collected at fallen trees in the water. The foam is part of the river’s ecosystem, and no reason at all to be upset about. However, I have to admit, it looks icky, but for another reason than being pollution.

Thus, foam also exists at beaches or along the coastline like seen in the photo below.

foam on Beaufort Seacoastline
Foam at the beach. “Beaufort Sea coastline” by ShoreZone is licensed under CC BY 2.0

Foam is made up from lipid molecules of decay

Don’t freak out about foam on the river, lake or at the beach. It is nature made, and a sign of healthy waters. The foam builds during decomposition of dead animals like dead fishes, water insects, amphibian, larvae, feathers from water birds, etc. and plant material including leaves that fell into the water.

Foam consists of fat oil molecules so-called lipid molecules. They once were the waterproof walls of plant cells or skins of creatures. As you know, oils and fats do not mix with water. They are also lighter than water. Therefore, the lipid molecules float as a thin film on the water.

Chena and Tanana rivers flowing together
Two Alaska rivers, the Chena River (foreground) and Tanana River (background) with wind driven waves in the rain

Wind produces waves when it attacks the water surface. The waves stir the water and with it the thin oily film. Consequently, air mixes with the oily, fatty film on the water. Bubbles form starting the foam development.

In areas, where the flow is slow or (temporarily) absent like on beaches, river banks, at trees fallen into the water, or at beaver constructions, foam can accumulate. There, the water can look like someone had dumped their dish water. The foam is an unexpected view and experience for Alaska visitors.


Finally, bacteria feed on the foam and, so to speak, clean up. The life cycle of eating and being eaten closes again providing new material for new foam on the water.

Color varies depending on uptake of material

While natural foam from decay is white, uptake of debris, pollen, spores, algae, silt and dirt can change its color. Yellow foam, for instance, most likely contains pollen.

How can you to distinguish natural from anthropogenic foam?

Natural foam differs from pollution caused foam. If the foam where from detergents or soaps, the foam would have some scent. Natural foam smells rotten, if at all.

Outfit of the day

The look of the day is a simple black layered tank-type style dress with high slits at the sides. I paired it with golden ruffled thong sandals. Black and gold always look great together. This look is perfect for the weekend, vaccation or even for dinner or brunch at a resort. You can find more on best resort style in the guide at the link.

fashion blogger in summer dress

over 50 years old woman in a summer dress with scarf

#styleover40 mature woman with LBD and green belt
Outfit details: Silk floral print scarf, Hermes collier de chien cuff, Apart slip dress, Hermes collier de chien belt, Madden girl sandals, headband, Hermes medor watch, and Chanel bag (all own)


Please feel free to pin the photos to your Pinterest post.

Don’t let your outfit be a random thing. Wear the right look in every situation by looking up what to wear when in How to Dress for Success in Midlife. Buy the book now.

When you found this post interesting and you want to learn more about Alaska’s natural phenomena then you may also like to read about funnel clouds in Alaska or when you are more down to Earth you may like recognizing faults in Denali Park. You can find the full collection of Focus Alaska posts in the Archive.

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Photos: G. Kramm

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