Stormwater management facility goldfish removal

​Protecting the North Saskatchewan River

The North Saskatchewan River is Edmonton's lifeline. It provides our community with drinking water, recreational opportunities and a beautiful river valley. It is important that we do everything we can to protect our river.

Aquatic invasive species threaten our river and local waterways. They are predators and competitors to native fish and their eggs and can quickly overwhelm native fish populations. Goldfish are considered an aquatic invasive species. EPCOR's regulator, Alberta Environment and Parks, requires that we mitigate the impacts of aquatic species in our stormwater management system.

The stormwater system directs snow melt and storm run-off from properties and streets to stormwater management facilities in our communities. The water in these facilities will eventually flow into local waterways and the North Saskatchewan River providing a pathway for goldfish to be introduced to our local environment.

EPCOR is assessing our stormwater management facilities to determine if goldfish populations are present. If they are found in our facilities we will take the necessary steps to prevent any introduction to the local waterways.

Goldfish cannot be relocated to another body of water. They are considered an invasive species across Alberta and there are no locations where they can be released.

Goldfish

Aquarium pets that are no longer wanted are often released into larger bodies of water as a way of "saving them" from the big flush or other means of disposal. While we know that people would consider this to be the best option, it is not. These fish will grow to fit their environment. In your aquarium they are small, in the wild they will forage and grow to sizes comparable to a football. Goldfish reproduce frequently and they will eventually overwhelm native fish populations. They are competitors for food and predators of native fish and their eggs.

Alberta's "Don't Let it Loose" campaign provides detailed information on the threats of goldfish in the natural waterways in Alberta. Please visit their website for information on what to do with your pets when you are done with them.

Removing goldfish from a stormwater management facility

The most effective and efficient way to remove goldfish from stormwater management facilities is to treat the facility with an organic pesticide that eliminates the fish. The pesticide used is called Rotenone and it is a naturally occurring compound derived from plants. An application of Rotenone affects the fish as they breathe in the treated water.

To be effective two treatments are required, about three weeks apart. This ensures that any goldfish eggs not affected by the first treatment are captured in the second. An application of Rotenone requires one full day.

Impacts to humans and other wildlife

The use of Rotenone does not pose a risk of adverse effects to humans or the environment. Animals that drink the water or eat the fish will not be harmed as their digestive enzymes will neutralize any residual pesticide.

During treatments at stormwater management facilities, temporary fencing will be installed to secure the area. This may include the closure of trails.

Goldfish around North America

Goldfish invasions of bodies of water is a concern around North America. Here are some links to media articles that reinforce the severity of this issue:

• People dumped their pets into lakes, officials say. Now football-size goldfish are taking over  – Washington Post, July 11, 2021
• More than 40,000 invasive goldfish found in one Alberta pond, officials say  – CTV Calgary, November 7, 2020
• Alberta city guts ponds of invasive "monster" goldfish  – CBC Edmonton, September 26, 2017
• Town to eliminate goldfish in ponds  – Okotoks Today, May 25, 2016

Stormwater Management Facilities under treatment

Currently EPCOR is working with our contractor, Advisian, to treat goldfish populations in Keswick.