Town of Ladysmith Wastewater Treatment Plant Upgrade

Ladysmith Harbour is an environmentally sensitive ecosystem, relied upon as a traditional food source by First Nation communities for thousands of years. Pacific Oysters, originally from Japan, were successfully introduced to Ladysmith Harbour in the early 1900s to support the commercial shellfish industry. The Harbour continues to provide a thriving habitat for shellfish, and also hosts a variety of community recreational and commercial activities.

The Town of Ladysmith has a clear vision for a prosperous, sustainable and resilient future. Ensuring the Harbour is not adversely impacted by the discharge of human waste is an important priority for the community. The Harbour has been closed to recreational shellfish harvesting for several years, and only limited commercial operations using comprehensive depuration processes are permitted.

The Town initiated a staged Liquid Waste Management Plan (LWMP) process in 2007, for which final approval was received from the BC Ministry of Environment in 2013. WSP facilitated the LWMP process for the Town, involving extensive consultation with regulatory agencies, the local community, and the Stz’uminus First Nation. Strong support was expressed for upgrading the Town’s wastewater treatment to protect the water quality in Ladysmith Harbour. The LWMP outlined the Town’s road-map for the upgrade program, and established key requirements, capacities and commitments.

Phases 1 and 2 of the proposed upgrades were constructed between 2009 and 2012, including new headworks infrastructure (influent control, screening and grit removal), compact Salsnes belt filters for primary treatment and a dewatering centrifuge.

The culmination of the upgrade program, Phase 3, was completed in 2017 and included a new secondary treatment facility with integrated laboratory, workshop and administration facilities, as well as various upgrades and improvements to existing plant infrastructure. Phase 3 also included a backup power supply and remote monitoring and control systems to enable continuous and efficient operation of the facility 24/7.

As Prime Consultant, WSP designed all phases of the upgrade. Phase 3 was completed in 2017 and included the construction of a new multi-level building, enclosing the secondary treatment processes with optimal odour control. The new building also includes integrated administration, laboratory and workshop facilities. The available construction footprint was very restricted, which led to the selection of the Moving Bed Biofilm Reactor (MBBR) process with Dissolved Air Flotation (DAF) for solids separation, providing high quality treatment in a compact area. This is the first time a MBBR-DAF combination has been used for municipal wastewater treatment in Western Canada.

Numerous sustainability initiatives were incorporated into the design including solar energy, effluent heat recovery for building heating and cooling, and reclaimed water for irrigation and non-potable plant use.

The quality of the treated effluent has vastly improved as a result of the upgrade, with Biological Oxygen Demand (BOD) removal improving from 54 to 98 percent, and Total Suspended Solids (TSS) removal improving from 70 percent to 98 percent.

The United Nations adopted 17 Sustainable Development Goals (SDGs) in 2015 as part of a new sustainable development agenda. We believe that WSP has an important role to play in contributing to achieving these goals. Here is the SDG associated with this project: