Consolidated Wastewater Treatment Plant – Marine Outfall – City of Powell River


City of Powell River

The Project:

Consolidated Wastewater Treatment Plant – Marine Outfall

The Scope:

JJM was contracted for the installation of 727 meters of 900mm diameter High Density Polyethylene (HDPE) marine outfall pipe onto the sea bottom, which would convey treated effluent from the new City of Powell River Consolidated Wastewater Treatment Plant into the Malaspina Strait in the Salish Sea (Gulf of Georgia).


In late 2021 the City of Powell River realized that the original contractor they had engaged for this project was insufficiently experienced to tackle the challenge presented in this project. The overall technical complexity was compounded by supply chain issues created by the COVID-19 pandemic. Supply chain ‘bottle necks’ made component parts, equipment and materials difficult to secure. JJM was approached to see if another viable solution could be created.

In order to address the technical concern that the Articulated Concrete Blankets might not provide sufficient ballast to keep the HDPE pipe at the sea bottom, JJM developed a solution using additional concrete pipe at set spacing to provide additional weighting. In addition, JJM’s experienced team was able to adjust project sequencing and work methodology to meet the project delivery deadline, mitigating the schedule impact of design and supply chain challenges.

As a result, JJM was able to successfully deliver this portion of a project that will be of lasting service to the City of Powell River area and will meet all provincial and federal treatment requirements.