As the largest single water investment ever for the City of Hamilton, the $340-million series of multi-stage, multi-year process upgrades for the Woodward Wastewater Treatment Plant continue to make headway into 2020.
As a Clean Harbour project, city officials are looking to enhance water quality in Hamilton Harbour by upgrading the facility as an objective of the Hamilton Harbour Remedial Action Plan. New tanks added by North American Construction at an estimated cost of $165 million, will be added to Woodward’s secondary treatment process to convert ammonia to less harmful nitrate on a year-round basis, reducing the amount of ammonia flowing into the harbour.
The massive undertaking for Woodward involves several sub-projects, including the replacement of the existing raw wastewater pumping station with a new station; expansion of secondary treatment to allow for nitrification; the addition of tertiary cloth filtration media for tertiary treatment; construction of a new Energy Centre with standby power; and construction of a new chlorine contact tank and outfall to Red Hill Creek.
The array of upgrades got underway in 2019 and won’t be completed until 2021. The upgrades project is being led by Jacobs as prime consultant, and AECOM.
The existing treatment plant is a conventional secondary treatment plant with chlorine disinfection and has an average day capacity of 409 ML/d and a peak capacity of 614 ML/d.
According to city officials, the raw sewage pumping station is more than 56% complete with form and concrete pouring underway.
The electrical system upgrade is more than 76% complete, with all ductbanks installed and rough-ins at the Power Centre complete. Cable pulling has begun along with installation of remaining switchgear.
For the secondary treatment upgrades, the demolition of the aeration and clarifier tanks for stage one construction activities are complete and modifications to these structures have begun. Piles and lagging have been installed and excavations are underway to support the addition of the new clarifier tank.
In documents about the secondary treatment upgrades, city officials say they still don’t know why a bypass gate in a Combined Sewage Overflow tank leaked 24 billion litres of combined sewage into Chedoke Creek during a period in 2014 when the gate was unexpectedly left open.
AECOM is the lead consultant on the construction of a new raw wastewater pumping station with a firm capacity of 1,700 ML/d set to be completed in 2020.