Businesses in Toronto may be eligible for a rebate on water that is used on-site for their industrial or commercial processes. The rebate is based on the percentage of water not returned to the sanitary sewer system, and is applied to the sewer portion of the water rate.

Eligibility Criteria

The program is open to industrial and commercial water customers that use purchased water for their on-site operations. The percentage by which the sewage discharge is reduced in relation to the amount of water purchased must meet the following criteria:

Property’s Total Annual Water Consumption Sanitary Contribution Amount
≤1500 m3 ≤ 80%
>1500 m3 but ≤15,000 m3 ≤ 85%
>15,000 m3 but ≤ 1,500,000 m3 ≤ 90%
>1,500,000 m3 ≤ 95%

Water that is discharged to sanitary or combined sewer systems, used outdoors (i.e. for irrigation) or transported off-site is not eligible for the Sewer Surcharge Rebate Program. For full eligibility criteria, refer to By-law No. 849 – Water and Sewage Services and Utility Bill.

Step 1: Send us a letter of intent

Submit a letter of intent by email to that includes:

  • Company name
  • Facility address
  • Contact information (full name, phone number, email address)
  • Water account number(s)
  • Water meter number(s)

Step 2: Submit the application*

You will have nine months from the date your letter of intent is received by the City to submit the application with all required documentation to (see Online Application Forms and Reporting Requirements section below). For the application to be accepted for consideration:

  • all City forms must be stamped and certified by a Professional Engineer of Ontario; and
  • contain all supporting material.

Step 3: Assessment and rebate*

If all documentation and information is received within the nine-month period, and your application is eligible, the rebate will be retroactive to the date your letter of intent was received. If the application received is incomplete, and all additional information is not received within 10 business days of being requested by the City, the rebate will be retroactive to the date all requested information is received.

Step 4: Subsequent applications

To continue to receive the rebate after the first year, all documentation (except the letter of intent) must be submitted annually by February 1.

If a renewal application is not received by February 1, or additional information requested by the City is not received within 10 business days of the request, the date of the rebate will be retroactive to the date all requested information is received.

*All communications will be maintained with the facility owner and the Professional Engineer of Record.

Provide an engineering report that follows this outline:


i. A completed Sewer Discharge Summary form (Excel).

ii. Background – An overview of the facility, the dates of the study periods, and a process flow diagram showing: connection to the City, water meter and sub-meter locations, process connections, discharge connections, outflow(s) to sewer, and other relevant appurtenances.

1. Total Annual Water Consumption

1.1 completed Purchased Municipal Water form. Include copies of the first and last month’s water bills for each water account in Appendix A.

1.2 Other Sources – Specify and provide meter readings or calculations for volumes for other sources of water.

2. Distribution to Non-Sanitary Components

2.1 Completed Cooling Tower form(s) for the makeup and blowdown water meter readings, as applicable.

2.2 Completed Boiler form(s) for the makeup water meter readings, and blowdown water meter or conductivity readings, as applicable.

2.3 Completed Product Water Content form(s). For each product include:

    1. a description of the product responsible for water consumption; and
    2. any calculations providing water content percentage or amount based on a minimum of three (3) separate (non-consecutive) periods of study or production records, showing seasonal variations in Appendix B.

2.4 For other processes, not included above, that divert water from the sanitary system, include:

    1. a description of the process detailed enough for City Staff to analyze;
    2. any calculations supporting your totals must clearly be explained and reference industry accepted methodologies and formulae;
    3. any other evaporation (not from cooling towers or boilers) must be explained in detail with calculations and equations provided to receive consideration; and
    4. a minimum of three (3) separate (non-consecutive) periods of study, records, or meter readings showing seasonal variations in Appendix C.


A. First and last month’s water bills

B. Production records and/or verification study periods

C. Other Process records and/or verification study periods


If you need help locating an engineer to help prepare the report, you may contact Partners in Project Green.

In 2020, a business consuming 100,000 m3 and diverting 20% of purchased water could receive a rebate of $46,438 (100,000 m3 x $4.0735/m3** x 57%*** x 20%).

Annual Water Bill for General Customer: 
$407,350 (100,000 m3 x $4.0735)

Annual Water Bill with Sewer Surcharge Rebate: 
$360,912 ($407,350 – $46,438)

**Rebate calculation applies to water rate paid by consumer, either the general (Block 1) or industrial (Block 2) water rate. See the current water rates.

***57% represents the portion of water rate charged for sewer use discharge (sewer surcharge). This rate of rebate is determined by City Council and can be subject to change.