Tuesday, June 21, 2011

Regina: Weir Opens, Foams Wascana Creek

The City of Regina opened part of the weir under the Albert Street Bridge this morning. The force of water churned islands and cliffs of foam along the south side of Wascana Creek.

As I watched not long after noon, six pelicans paddled through the surreal suds, bobbing through what looked like chunks of Styrofoam — and amazingly, their legs were strong enough to keep them moving forward against the power of the rushing current.

Foam in Wascana Creek - photo by Shelley Banks
Several pelicans drift (middle, in front of high foam). © SB 

Pelicans in foam in Wascana Creek - photo by Shelley Banks
Close up: Forth by bridge. © SB 
Despite the towering froth — or perhaps because of the slower eddies where it settled — the pelicans stayed on the south side, paddling along the shore, weaving out through chunks of foam, then up over lacy swirls of froth to the Albert Street Bridge, and back again.

Strange to me, but they didn't seem bothered at all by the suds that billowed behind, beside, around them.

But how would I know how pelicans really feel?

My logic is that if they didn't like the foam, they'd fly away — but perhaps they stayed in these snow-white meringues unwillingly because the rewards of food there were so great. I mean, they liked the food enough to endure the foam.

But what are these thick bubbly drifts? Are they safe and natural?

Pelicans in foam in Wascana Creek - photo by Shelley Banks
Swimming through islands. © SB
The Alberta Environment publication, Foam on Surface Waters (a very easy read — with pictures), says it can be natural and neutral, the result of soluble organic material, the same substances from plants and trees that cause the tea-brown colour of the water. Some of these dissolved compounds are "surface-active agents," or surfactants. These lessen the surface tension of the water, and when the water is vigorously mixed and air is churned in, bubbles form — and bubbles build up to create foam.

It's the same process that creates bubble baths.

Pelicans - bird bubble bath? - photo by Shelley Banks
Bird bubble bath © SB  
So frothy stuff is common when fast moving water (with chemicals from decomposing plants) thrashes through rapids and churns over dams.

But are billows this white and this high really natural? Or are other elements involved?

Foam goes on to say that the synthetically produced surfactants used in household products (detergents, shampoos and toothpaste) can also be released in surface waters, and, yes, create river foam.

And a 2006 Washington Post story about foam on Virginia's James River suggested the culprit in that case could be pollution — phosphorus from sewage plants, manure-laden farm runoff, suburban lawns and others watershed sources.

But others say river foam is harmless. That's what a city engineer from Moose Jaw (a city so near Regina its water must be the same) told the local paper last year. A natural occurance, caused by organic phosphates from plants and grasses, he said.

So synthetic or natural, soap or decay, pollution or organic?

Whatever the origin on this foam, I can only wonder at the pelican's apparent acceptance, and even — or so it looked today — enjoyment of it.

Pelicans submerged in foam - photo by Shelley Banks
Is this really safe? If so, relax, and count the pelicans!  © SB  


And why was the weir opened? Yesterday, in announcing the plan to remove part of the weir — aka, a small dam — the City of Regina news release said Wascana Lake was two feet higher than normal, the result of spring melt combined with the 50 mm of rain that fell here on Friday. As the flow moves downstream, the City warned there will be fast flowing water and undertows. Residents were reminded to stay safe and keep children and pets away from the water.

I stood on the bridge for these shots...

And so, a note on perspective: Given how far above I was (see first picture), and the fact that I was looking down on the birds and the creek and the foam, these images will show the foam as lower/smaller than it actually was. (Just in case anyone thinks I played with camera angles to make the billows so high...)  


Update: A day later, CBC News discovers the foam. See: Foam on Wascana Creek Not Dangerous?
Update: August 29, 2011: Wascana Creek Polluted and at Risk?


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