Algae, and aquatic bugs can speak volumes about what's happening in local aquatic ecosystems, which is why watershed specialists regularly check in on how they're doing. It's called biomonitoring and it helps to guide operations at EPCOR – where treating wastewater is core to their business.

Wastewater is everything you flush down the toilet and pour down the sink. Without effectively treating this wastewater, excessive nutrients, organic material and bacteria would be discharged into our rivers and severely impact local aquatic ecosystems.

"Treated wastewater is rigorously tested to ensure it meets federal water quality guidelines and provincial limits," said Mike Christensen, Environment Technologist at EPCOR. "Our ultimate goal is to protect and preserve local waterways and the organisms that live in them, and biomonitoring plays an important role in meeting that objective."

Biomonitoring uses aquatic bugs or invertebrates and algae to measure how rivers are functioning ecologically.  This data is collected both upstream and downstream of wastewater treatments plants and compared to detect any significant changes that might have occurred due to the wastewater treatment plant's effluent.

EPCOR's watershed specialists are always hard at work monitoring the river water.

So what does algae say?

While it might look like 'slime' or 'mud' to some, there are typically dozens of different types of algae growing on river rocks. The amount and types of algae speak to the amount of nutrients being discharged from wastewater treatment plants. Naturally-occurring nutrients like phosphorus and nitrogen might sound like a good thing, but even small increases in these nutrients can increase algal production. Even in healthy rivers, you will often see algae growing on rocks, but large thick "furry-looking" mats may be a sign of excess algal growth, and has the potential to use up dissolved oxygen in the water and suffocate fish who need that oxygen to breathe.

To perform algae biomonitoring, watershed specialists collect rocks and scrape algae off, sending collected samples for analysis. The goal is to find a variety of algae species typical to healthy rivers, in low quantities, and no significant difference in the algae between upstream and downstream of water treatment plants

What do the bugs say?

Similar to algae, when looking at bugs – or benthic invertebrates – the specialists look at the number of invertebrates collected, and the variety of species. Many of these bugs are familiar to those who fly fish and include stoneflies, caddisflies, dragonflies, mayflies, and chironomids and each species has a specific and important role to play in the aquatic ecosystem.

Watershed specialists sample the river and determine the amount and types of invertebrates found. The absence of certain species may indicate that too many nutrients are making their way into the river.

"Ultimately, it's these bugs and algae that have the potential to alert us of a changing environment and inform our ongoing wastewater treatment plant operations," added Christensen.

To learn how you can help protect and preserve local waterways by keeping the wrong things from going down your toilet or drain, visit