Project Background and Materials

​The Duggan sanitary sewer line services neighbourhoods in southwest Edmonton, from Steinhauer up to Bonnie Doon. Construction on the new Duggan Tunnel began in March 2023 and is expected to be completed by the end of 2024.​

About the Duggan Tunnel

The Duggan tunnel sanitary sewer moves wastewater from south Edmonton to the Gold Bar Wastewater Treatment Plant. The existing sewer is approximately 30 metres deep and was originally built by hand. The existing Duggan sanitary tunnel services the Edmonton region highlighted on the map:

​The new tunnel has been identified for replacement due to poor condition and to help address odour in the area.​​

See project map on homepage

Odour Reduction

​How are we helping with odour in your neighbourhood

EPCOR is aware of consistent sewer odour issues in several neighbourhoods along the alignment of the Duggan Tunnel, particularly in Steinhauer. This project is part of EPCOR’s Corrosion and Odour Reduction Strategy (CORe). The strategy aims to understand and mitigate sewer odour issues and will result in significantly reduced sewer odour city-wide by 2031. With completion of the new tunnel, we expect the major cause of how odour is formed and pushed out into the communities to be notably diminished.​​

Why is there odour and how will the project help?

The existing Duggan tunnel serves as both a sanitary and storage tunnel and is just over three kilometers long. This means that sanitary flows are stored in the tunnel during wet weather events.

The existing Duggan tunnel has various shifts in depth along the alignment. When built in the 1960s, crews didn’t have the equipment or technology to easily tunnel through the existing sand layer, so they had to tunnel above it or below it. This variation in depth increases the movement of the sanitary flow (up and down), which increases the amount of odour generated. The new tunnel will flow by gravity (not up and down), which will reduce the amount of odour pushed out into the communities.

How odour develops in the existing Duggan tunnel:​

​Other ways we are helping with odour

What else are we doing?

Sometimes, creating a change in one area can increase sewer odours in another. This is why EPCOR has a city-wide strategy and why the work must occur in a specific sequence.

Some steps have already begun, allowing for better access to infrastructure to inspect lines and investigate odour issues:

• Two access manholes were built along 104A Street near 48 Avenue to support inspection, monitoring and cleaning of the sanitary system. This work was completed in May 2020.
• Projects have been completed/underway to reduce odour issues at three local pump stations (Kaskitayo, Blackburn and Twin Brooks). These projects focus on moving the flow of wastewater more quickly to reduce stagnation.
• Four access manholes in Empire Park and Pleasantview were completed, allowing for better access and cleaning.
• Manhole seals and airflow control devices have been installed at the intersection of 34 Avenue and 106 Street, and at several key junctions along 106 Street from 34 Avenue to Whitemud Drive.
• In 2021, a surface air quality monitor was installed at the 34 Avenue and 106 Street intersection to monitor the concentration of odours in the area​.
  

Residents are encouraged to report an issue any time an odour is overly strong by calling EPCOR Trouble at 780-412-4500. This helps us to track the odour to look for patterns and potential solutions.​​​​