COLUMN: Small streams, huge role
There is a sign that I pass by every day, reminding me about the sensitivity of a particular stream I cross, and its importance to salmon habitat.
But two weeks ago, it wasn’t just water flowing through the creek. It was a putrid black sludge that experts suspect was raw sewage – likely the contents of a septic tank that was pumped into a ditch that flows into the Little Chilliwack River.
Fortunately, the recent heavy rains have flushed the viscous goo through the system and into the Fraser River. The impact is likely to be minimal, say environment officials.
But still, the odour of criminal irresponsibility and thoughtlessness hangs in the air like the stink of a well-used outhouse.
It’s difficult to imagine the thought process that would lead someone to drain raw human waste into a local stream, particularly one that flows past people’s homes.
Aside from the illness it can cause (a neighbour has since reported flu-like symptoms in his family), the sewage can be devastating to aquatic life.
That’s because the bacteria rampant in the sludge uses up all the oxygen in the water, leaving nothing for the fish who dwell there.
And a little pollution can do a lot. For example, it’s estimated that one litre of oil can contaminate seven million litres of water.
True, the Little Chilliwack River is small. But don’t think it is of little importance to salmon habitat. Urban streams throughout the Lower Mainland play a vital role in the health of salmon populations. The Fraser River may well be the most important salmon spawning river in the world. However, the creeks and streams that feed into it provide critical spawning grounds for several species. Indeed, according to the Outdoor Recreation Council of B.C., urban streams in the Lower Fraser Valley “are responsible for producing 65 per cent of the coho salmon and almost all of the chum salmon found in the Fraser Basin.”
But those streams are becoming as threatened as the fish and wildlife they support, ORCBC says.
Where once there were more than 750 urban streams in the Lower Fraser Valley, there are now only 106 that are considered healthy. Most have been lost to urban expansion. But even those that are healthy are put at risk every time someone allows motor oil, antifreeze, or any number of chemicals to flow into a storm sewer.
Streams around Chilliwack face their own challenges, mostly from the intensive farming activity that is such a vital part of our local economy. But urban development has also put a strain on this delicate habitat through channelling and increased encroachment.
That just makes it all the more important that we take care of what we’ve got. Urban streams, and the drainage ditches that feed them, are not dumping grounds. They are the capillaries that support the larger health of the Fraser River Basin.
As the sign by the Little Chilliwack says, the salmon that the river supports are an important part our heritage. We must ensure that it – and so many streams like it – remain healthy and don’t fall victim to the kind of idiots who see nothing wrong with pumping raw sewage into them.
Greg Knill is editor of the Chilliwack Progress, a sister paper to The Leader.