What’s all that foam about?

Learn about telling the difference between naturally (and unnaturally!) occurring foam on your river.

(Photo: Natural foam build up near Ottawa Rowing Club on the Ottawa River. Photo courtesy of Paul Mudroch.)

If you’ve seen foam on the surface of one of your favourite waterbodies, there’s most likely no cause for alarm. The majority of foam we see on our river is just the result of organic matter in the water.  When organic matter like leaves and twigs begin to break down, they release compounds into the water called surfactants, which create foam when water is turbulent. You can often see an example of foam build-up right downtown Ottawa near the Ottawa Rowing Club, where it can get up to a meter high.

Naturally occurring foam usually smells like fish or earth and has tan color.  If you pick it up, smell it and it smells earthy, it’s our natural foam.

Usually unnatural foam has a really strong perfume coming from it, like soap. If you find foam that smells like perfume and is white, this indicates the presence of anthropogenic surfactants from detergents and soaps and is an indication of pollution.

Read more about foam with RappFLOW.

pollution hotline magnetSee Unnatural Foam on the Ottawa River?

Call Ottawa Riverkeeper’s Pollution Hotline at 1-888-9KEEPER or fill out our electronic form. We can help you report the problem.

3 responses to “What’s all that foam about?”

  1. foam on Ottawa River says:

    Today is December 7, 2015, I live in Lefaivre Ontario across from Gascon Street. This morning I noticed not only foam but also a strange whirling of the water on the river, snake like about 300 meters long. The river is flowing quietly except for this phenomen

  2. Deb Bodine says:

    We have had foam flowing into Flagg Bay which is between Morrisburg and Iroquois, just off the St. Lawrence for almost a week. Who can I contact to make sure it is safe? Thanks!