Island Water Treatment Plant Capacity Increase Study

Municipal Class Environmental Assessment

BackgroundIsland Water Treatment Plant

• One of the City of Toronto’s four water treatment plants

• Supplies approximately 20% of the City’s treated water

• Built in 1977• Capacity of 410 million

litres per day• Operates 24/7• Only accessible by ferry or

marine transportation

• Supplies drinking water to the City’s residents, visitors and businesses

• Supplies extremely cold water to the Deep Lake Water Cooling project– Partnership between City of

Toronto and Enwave District Energy Limited

– Provides air-conditioning to businesses in the downtown core

Island Water Treatment Plant

Island Water Treatment Plant

Opportunity

• City desires to obtain greater operational flexibility by increasing the processing capacity of the Island Water Treatment Plant from 410 mega litres per day (ML/day) to 450 ML/day– This is desired to sustain peak production flows.

Alternate Solutions

1. Maximize the production capacity and treatment performance of the existing infrastructure at the Island Water Treatment Plant

2. Design and construct additional treatment infrastructure on the Island Water Treatment Plant site

3. Do nothing

Evaluate Alternate Solutions

• Desktop assessment and modelling indicates that increase in capacity can be achieved through maximizing production capacity and treatment performance of existing infrastructure. No construction is necessary.

• Do nothing alternative is screened out because it does not realize the opportunity, but is carried forward to provide context for evaluation.

Least Favourable Neutral Most Favourable

Evaluating Alternatives

Evaluation CriteriaMaximizing production

capacity at existing plant

Constructing additional treatment infrastructure Do nothing

Obj. Achieve 450 ML/d

Public

Construction impacts (noise, safety risks, etc.)

Operating impacts (noise, safety risks, etc.)

Environmental

Construction impacts

Operating impacts (energy use, etc.)

Cost

Capital Operating

TOTAL 20 10 18

Recommended Solution

• Maximizing the production capacity and treatment performance of the existing infrastructure at the Island Water Treatment Plant up to the desired 450 ML/d

Next Steps

• Public consultation:

Next steps:

2014

June July August

23 30 7 14 21 28 4 11 18 25

Review recommended solution with public

Select preferred solution

Notice of completion to agencies and public

30 day review period

Start implementation