When you ask someone about the quality of the North Saskatchewan River, clean might not be the first word they respond with. But saying the North Saskatchewan River is “dirty” isn’t correct. The early history of our river and its muddy brown appearance are both partly responsible for misconceptions about the health of the river today.
The river’s quality has improved significantly in the last half-century, and bacterial levels have lowered to those measured in the 1920s, despite a 10-fold increase in population.1 Improvements in water quality are primarily due to improved sewage and wastewater treatment, though a better understanding of how to protect and manage our watershed have also contributed to increased health. Yet misconceptions about its health are still widespread, and this challenges our community’s connection to the watershed. We’re hoping to change the perception of our watershed through outreach and education.
Just because its brown, doesn’t mean it’s dirty.
The appearance of the North Saskatchewan River is mainly due to natural processes. In the spring, the river is a muddy-brown colour because of sediments and silts, which are washed into the river as snowmelt and rainfall increases.2 The colour of the water changes in early to mid-summer, when water flow is reduced and sediments settle.3 The river is particularly prone to this muddy colouration when it flows through Edmonton due to natural topography and high levels of erosion.
Today, a few sources of pollution do threaten our water, primarily in the form of discharge from storm sewer outfalls and combined sewer overflows (CSOs). Urban and agricultural runoff deposit heavy metals, nutrients, and other contaminants into our waters. However, these only pose a threat to human health during heavy rainfall and snowmelt.
Discharges into the river continue to be reduced, and stormwater is being better treated. There is also a trend towards wastewater reuse. All of these are contributing to increasing health of our watershed.4
Our river wasn’t always clean, and that’s a big reason we think it’s dirty today.
Standing in the river valley today, you wouldn’t know that this beautiful urban escape was once a dumping ground for toxic industrial waste. But it was: in the early 20th century, downtown Edmonton was a booming industrial landscape, and the river valley was populated with coalmines, brickyards, garbage dumps, and slaughterhouses.The North Saskatchewan River was a natural effluent for all of these. On top of this, logging operations used the river as a float for log booms, and dredging equipment cluttered the river. Combined with untreated human waste that was routinely discharged into the river, the North Saskatchewan endangered those who dared to drink or come into contact with it with real threat of disease and infection. 3
In the early 1950s, an assessment of the water was done and results were chilling: by the time the river reached the Saskatchewan border, there was no dissolved oxygen left, and no life could be found in the river. These findings were pivotal to our understanding of the watershed – and we began to take steps to protect and manage our watershed.4
Today, the North Saskatchewan River is (mostly) clean and safe to swim in.
But there’s always more we can do, and we need to continue to protect and maintain our watershed to ensure it stays that way.
- Bunner, Paul. (October 23, 2014). I swam in the North Saskatchewan River and lived to tell this tale. Retrieved from: http://www.rivervalley.ab.ca/2014/swam-north-saskatchewan-lived-tell-tale/.
- City of Edmonton. (2015). North Saskatchewan River – Water Quality. Retrieved from: http://www.edmonton.ca/city_government/environmental_stewardship/north-saskatchewan-river-water-quality.aspx.
- Marcellin, Josh. (May 2015). River Valley Alliance.The North Saskatchewan River has killer angling right in Edmonton. Vue Weekly.Retrieved from http://www.vueweekly.com/the-north-saskatchewan-river-has-killer-angling-right-in-edmonton/.