Two common measurements of wastewater strength are biochemical oxygen demand (BOD) and total suspended solids (TSS).
BOD measures how much oxygen is consumed by microorganisms in order to break down the organic matter. A high BOD means that less oxygen is available for aquatic life.Provincial and federal regulations require, over an approved period of time, that all wastewater treatment facilities provide secondary treatment or better. Our Liquid Waste Management Plan makes a commitment to provide secondary treatment at Nanoose Bay Pollution Control Centre (NBPCC) in 2023.
TSS is a measure of solid pollutants that would be captured on fine filter paper. They are visible in water and decrease water clarity. High concentrations of TSS can cause problems for aquatic life.
Secondary treatment upgrades are underway for Greater Nanaimo Pollution Control Centre (GNPCC). Sign up for regular email updates.
The graph below shows the BOD and TSS reduction capacity of primary and secondary treatment facilities.
Below is a possible scenario of the expansion to secondary treatment at GNPCC. Changes may be made in both the technology used and the layout.
Many questions around plans for the GNPCC Secondary Treatment Upgrade Project are answered below. If you have further questions, please contact Sean De Pol at 250-390-6560 or email firstname.lastname@example.org.
A: The construction is required to upgrade the facility from primary treatment to secondary treatment. It will benefit the community because secondary treatment will improve the quality of the effluent discharged to the marine environment.Q: What is secondary treatment and why do we need to upgrade?
A: Secondary treatment improves solids removal and reduces the oxygen demand on the marine environment. The upgrade is required to meet the RDN's approved Liquid Waste Management Plan, the Provincial Municipal Wastewater Regulation and the Federal Wastewater System Effluent Regulations.Q: How much will this project cost me as a homeowner?
A: The average annual sewer tax for wastewater capital projects, operations, and maintenance at GNPCC is now about $110. The average household will see an average annual tax increase of $6-18/year over the next eight years to fund major capital projects at GNPCC. The RDN will explore provincial and federal funding opportunities to reduce the amount required from local taxpayers.Q: When will construction start / end?
A: Site preparation (tree removal, stump removal, soil removal) began in 2015. Treatment plant construction will begin in mid-2016 and be complete mid-2018.A preliminary construction activity schedule is provided below:
|GNPCC Process Selection Report||Complete|
|February 10 and 11, open house||Complete|
|Detailed engineering design||2015 to 2016|
|Environmental Impact Study - Draft||Complete June 2015|
|Public Information Meeting||July 8, 2015|
|Stump and soil removal||Complete 2015|
|Environmental Impact Study - Final||Complete January 2016|
|Open House||June 11, 2016|
|Construction tender||Fall 2016|
|Public Information meeting||Before construction begins|
|Construction||2017 to Fall 2019|
Q: What are the expected hours of construction?
A: Typical construction activity will conform to the City of Nanaimo Noise Bylaw which states that noise due to construction shall not be caused before 7:00 am and after 9:00 pm Monday to Saturday and before 9:00 am and after 9:00 pm on Sundays and Statutory holidays.Q: What are you doing about odours that come from the plant?
A: The existing odour control facilities will be upgraded as part of the secondary treatment project.