You asked about the Water Rate Structure Review

Published on
June 27, 2024
Water and environment

The City is currently running a public engagement campaign to get feedback and opinions to inform its review of the Water Rate Structure – with the focus on how to effectively recover costs for delivering water, wastewater and stormwater services. Council has directed City staff to review how we recover the costs to deliver water, wastewater and stormwater services. The public engagement includes a survey, which runs until July 31, and several consultations with residents and partners. The survey and session dates are found on

We want to share answers for some frequently asked questions.

Some background first

Before we profile some of the common questions, here is some brief background, in case you are not quite up to date with the review. 

The existing water rate structure came into effect in 2019, and it introduced variable consumption rates to calculate a portion of the drinking and wastewater services. The first tier was the lowest rate and rose at each of the remaining three consumption levels. Fixed charges represent the majority of cost to deliver reliable drinking water and sewer services. However, only 20% of the costs to deliver these services are recovered from fixed charges.

The stormwater rate did not change in 2019, rather, it maintained the fixed charge established in 2016. The charge was based on property type, and for non-residential properties was calculated based upon property assessment values. 

When the new structure was put in place in 2019, City Council directed staff  to conduct a periodic review of the water rate structure to ensure the system remains fair and equitable.. As part of the current review, Council directed staff to specifically examine options for how the stormwater service can be calculated more equitably. With advancements in technology, the City now has the ability to use impervious surface data – which has a direct correlation to how much of the property cannot absorb run-off which impacts the amount, quality and rate of the stormwater runoff.  This is one option being considered.

The City is now asking residents and partners for their feedback on how the water, wastewater and stormwater charges can be done in a fair and equitable manner, to meet the costs of providing these services.

Here are answers to some of the questions we have heard so far.

What are the main objectives of the water rate review?

Fairness and equity

  • Ensures that services are paid for in accordance with the benefit received.
  • Improves equity in stormwater billing distribution.


  • Ensures that the level of consumption required to meet basic needs is affordable.


  • Follows industry best practices and is easy for the public to understand and the City to maintain.

Financial sustainability

  • Recovers the full cost of operating the systems and keeps the infrastructure in good repair.
  • Ensures the appropriate fixed cost amount is captured to guarantee the requirement is collected.

Support economic development

  • Keeps Ottawa’s rates comparable with similar Ontario municipalities.

Promote conservation

  • Provides a financial incentive to reduce the amount of impervious space and reduce consumption, as well as encourage water conservation and help manage the demands on the water system.

Why is the City reviewing the Water and Wastewater rate structure? 

Council has directed City staff to review how we recover the costs to deliver water, wastewater and stormwater services. We are reviewing the current model to ensure transparency and accountability, to better align the fixed costs to deliver services with the fixed costs recovered form bills, to continue to reward conservation and simplify the rate structure for property owners. The fees for water, wastewater and fire supply will continue to be separate charges and will each continue to all have a fixed component.

How will this affect my water bill?
We are currently looking at our tiering model and fixed costs to ensure they are fair and equitable for residents and businesses. We are aiming to ensure alignment of our water and wastewater fees with the six principles outlined in this review. No decisions or models have been created yet, all information gathered will be used to create some options that will be presented to City Council in 2025 for consideration.

How are the stormwater fees currently calculated?

Since 2017, the stormwater fee structure for residential properties includes a basic rate, with discounted rates for those not connected to City services and is based on property type and service area.  Non-residential properties are contributing based on their MPAC property value assessment.

More information on the 2024 water utility rates can be found on

What methods are you considering for stormwater billing?

Various methods are being explored for the basis of stormwater billing. Information gathered from our survey and the consultations will help define options for City Council consideration.

These include:

  • The Status quo - based on property type, service area , service type and assessment value.
  • A tiered model based on averages of impervious space.
  • An exact model based on the actual amount of impervious space of each property.
  • A blended option that allows for exact impervious calculations within established tiers.
  • Ideas and suggestions from the consultation process

What is impervious space and why is the City considering this method?

Impervious space refers to the total paved or other hard surface area of a property, like rooftops and pavement, which are considered highly resistant to the infiltration of water. Impervious area has the most significant influence on the amount, quality, and rate of stormwater runoff.

Are City staff proposing an increase to my stormwater fee?

Staff are in the process of consulting on the rate structure options. It is important to note that no decisions have been made. All information gathered will be used to create some options that will be presented to Council in 2025.

How would impervious data be captured? 

Once aerial imagery is captured and subsequently processed into viable pixel imagery, it needs to have vector mapping applied, essentially drawing lines and shapes around structures and features for identification. With advancements in technology, the use of artificial intelligence (AI), in combination with geographic information system (GIS) property data overlay which provides impervious data per property, the GIS unit can now accurately account for hard surface data at the property level.

What would be considered as impervious? 

As part of the consultation, staff have a preliminary list of what could be considered as impervious spaces. This list is not final and we are listening to feedback on what should be considered.

  • Buildings and other miscellaneous structures (Including patios and decks)
  • Pavement (asphalt, concrete, gravel, or other hard surface) for the following uses:
    • Private roads
    • Driveways
    • Parking lots/spaces
    • Sidewalk/ walkways
  • Concrete pads
  • Exposed bedrock
  • Tennis courts, basketball courts
  • Solar panel farms

For the purposes of stormwater billing the following features are on our list to NOT be considered impervious.

  • Open space
  • Grass
  • Gardens
  • Sports fields (both natural and synthetic turf)
  • Forest
  • Crop or pastureland
  • Exposed soil (including dirt driveways)
  • Water bodies including ponds, lakes, and streams.
  • Riprap or other outlet protection associated with
    • stormwater management facilities
    • ditches and streams
    • erosion protection/property drainage i.e., Stone/gravel used as mulch in landscaped beds.
  • Tombstones
  • Patio furniture, fences, wood piles
  • Swimming pools

What are the next steps in the review?

Staff will be continuing with consultations in the rural areas until the end of June. Consultations with businesses, community groups and industry, commercial and institutions will take place over the summer. Later this year, we will also provide property owners and partners the opportunity to review the proposed options and provide  feedback. Once all the feedback has been gathered, staff will be reporting back to City Council in June 2025. Once a decision is made by City Council, staff will inform all property owners of the changes and implementation dates.

To keep informed, visit our Engage Ottawa page regularly for opportunities to participate.