Note: HMM, a joint venture of Mott MacDonald and Hatch, was also retained to provide detailed design and construction administration for the Keswick plant's new outfall, a project that was the runner-up for Trenchless Technology's 2013 Project of the Year.
Opportunity
Lake Simcoe in southern Ontario was known to the indigenous Hurons as “Beautiful Water.” About 19 miles long and 16 wide, it is the fourth largest lake located entirely within the province, with a watershed that encompasses roughly half a million people. Georgina Island, the largest of Lake Simcoe’s islands, is a reserve for the Chippewa First Nation people.
The Keswick Water Pollution Control Plant helps protect the waters of Lake Simcoe by treating sanitary wastewater generated around the Town of Georgina, where the community of Keswick is located. The plant utilizes an extended aeration process to achieve regulatory discharge limits.
Due to significant growth in the area, it became necessary to increase the rated capacity of the plant by 50%. The plant was rated at 12,070 cubic meters per day, and was operating at approximately 85% of that capacity when the expansion was authorized.
Solution
HMM, a joint venture of Mott MacDonald and Hatch, was engaged to provide engineering services to upgrade and expand the wastewater facility. These services included conceptual and final design, permitting and approvals, bid tender preparation and bid tender period assistance, construction administration and resident site supervision, and the commissioning and startup of the facility.
Our scope of work provided the engineering for the following project components:
- Construction of a new aeration tank with fine bubble diffusers
- Replacement of coarse with fine bubble diffusers in two existing aeration tanks
- Construction of a new screening and grit removal facility
- Construction of a new odor control facility
- Pilot studies of two membrane technologies for tertiary filtration
- Decommissioning and replacement of the shallow bed sand filter with tertiary membrane filtration
- Decommissioning and replacement of the chlorine disinfection system with UV disinfection
- Upgrades to the electrical, HVAC, solids handling, and chemical facilities
An important feature of the project was the upgrade and expansion of the supervisory control and data acquisition (SCADA) system. Our scope of work included the following:
- SCADA architecture, network drawings and software specifications
- Electrical design including single line diagrams, wiring diagrams, schematics, panel layouts, and motor control center (MCC) design
- Programmable logic controller (PLC) card wiring diagrams
- Process control narratives describing the sequence of operations, including set points, automatic logic descriptions, and input/output listings
- Site inspections and assistance to electrical contractor
- Operation and maintenance manuals
Outcome
During a tour of the plant in the summer of 2012, Environment Minister Jim Bradley said the work at the Keswick plant could be a model for other communities.
“We look upon it as an investment, as opposed to an expenditure, in the quality of life for people. Ontarians want a healthy, vibrant Great Lakes that are drinkable, swimmable and fishable. By helping communities find innovative wastewater treatment solutions, our government is finding ways to keep our [lakes] healthy.”
According to Bradley, water and wastewater are the largest subsector of Ontario’s environment industry, employing 22,000 people and generating CDN $1.8 billion in local revenues.
Regional environmental services commissioner Erin Mahoney said that the upgraded plant, currently serving about 25,000 people, would be able to serve 50,000 and still reduce its phosphorus output by half, from 2,866 pounds (1,300 kilograms) per year to 650.
York Region chairperson Bill Fisch said, “One of our goals is protecting Lake Simcoe in the best way possible and I think we are doing that here.”
Award
In 2015, the project was named Project of the Year, Environment (Greater than $50 Million) by the Ontario Public Works Association. It also received an Award of Excellence from the Consulting Engineers of Ontario (see video). For more details, see p. 20 of the Consulting Engineers of Ontario magazine Accolades.