Learn about the City of Toronto’s Sewer Infrastructure and Sewer Assessment Guidelines

In order to comply with the City of Toronto’s guidelines (as well as follow best practices when it comes to sewer maintenance and/or land development), you need to understand how a sewer capacity assessment works. Otherwise, your project may encounter unanticipated roadblocks or, the sewer system may face a number of costly issues, such as:

• Inflow and infiltration
• Sewer back-ups
• Spills
• Overflows
• And more

In other words, performing a sewer capacity assessment that meets municipal guidelines can save you a lot of time, money, and headaches.

Below, we dive further into how a sewer capacity analysis and overall assessments work.

Understanding Sewer System Infrastructure

Let’s first look at some of the terms you need to understand when looking at the City of Toronto’s sewer system.

We’ll start with the different types of sewer connections.

In Toronto, a property will have one of three types of sewer connections:

• A single connection, which is when a property is directly connected to the city’s sanitary sewer;
• A “Y” connection, which is when two properties are connected through a single connection to the city’s sanitary sewer; and
• A header connection, which consists of more than two properties that are connected, via a header, through a single connection to the city’s sanitary sewers.

The infrastructure of the sewers can be further broken down into two types of sewer systems in Toronto.

Separated Sewer System

Separated systems are comprised of sanitary sewers and storms sewers.

Sanitary sewers are designed to transport wastewater released from a drain, toilet, sink, or appliance such as from a washing machine or dishwasher. This wastewater from residences and businesses flows to treatment plants where it is cleaned before being released into Lake Ontario.

Separated storm sewers capture rainwater or snowmelt. Much of this is captured through catch basins, the square grates on the side of the road. This water flows directly into nearby waterways including streams, rivers, and Lake Ontario.

There is a separate storm sewer analysis and a sanitary sewer capacity analysis that tests these specific systems on how well they can perform their unique duties. These should be part of your overall sewer capacity analysis.

Combined Sewers System

Roughly a quarter of Toronto (typically found in older areas of the city) has combined sewers, built about a century ago. Combined sewers have only one pipe that carry both sewage and stormwater. Most of the time, combined sewers carry all contents (rain, melted snow, and sewage) to wastewater treatment plants for full treatment.

During periods of heavy rainfall, combined sewers may fill beyond capacity, causing a combined sewer overflow.

These types of sewers again require specialized sewer flow monitoring services, wastewater management techniques, water flow monitoring, and wastewater monitoring to ensure that the issues outlined earlier don’t occur.

In other words, you want to make sure that your sewer capacity assessment identifies any issues proactively before they can waste your time and money. You also need a specialized sewer capacity analysis to identify said issues and be able to manage inspections of all different types of Toronto sewers.

General Guidelines for Sewer Design in Toronto

For any developer or engineer in Toronto interested in connecting to the sewers, there exists a guideline on how sewer capacity assessments are performed.

This consists of a capacity assessment and procedural guidelines, which include:

• An onsite discharge investigation
• Hydraulic grade line analysis of design flow
• Design flow mitigation measures
• Hydraulic grade line analysis of wet weather flow
• Wet weather flow mitigation measures

You can find more information about the guidelines here.

Sufficient to say, a sewer capacity assessment can be difficult without having all the relevant data on your sewers easily accessible, and without having inspected your sewers for potential impediments before having the city inspect your development.

The guidelines also have capacity criteria for your sewers, which we’ll explore more below.

Capacity Criteria for Sanitary and Combined Sewers

See below for the capacity criteria from the City’s guidelines:

How Civica Helps with Wastewater and Stormwater Management?

We now understand a bit more about all that goes into a sewer capacity analysis and assessment. But the thing is, ensuring your sewers meet these guidelines on your own can be a dauting task, and one fraught with the potential to make expensive errors.

At Civica, we have years of experience consulting with private and public entities on their sewers, and we combine industry best practices with premier technology to ensure that your sewer systems are fully functional and free from potential dangers.

We provide a range of sewer inspection services that identify potential obstacles, including:

• Water flow monitoring
• Wastewater monitoring
• Sewer flow monitoring services
• Wastewater management consulting
• Sanitary sewer capacity analysis
• Storm sewer capacity analysis
• And more

Benefits of Engaging Civica’s Flow Monitoring and Sewer Capacity Analysis Services

With Civica as your wastewater and stormwater management partner, you’ll experience a range of benefits, including:

• Saving time and resources
• Environmentally safe methods
• Deep industry knowledge
• Accurate and current data/information on your drainage and other sewer-related assets
• NASSCO-certified operators and inspections that meet PACP and MACP standards
• Rapid reporting with GIS-based outputs
• Inspections during wet weather to identify issues on the spot
• And more

Our team follows all the relevant City of Toronto guidelines, ensuring compliance with City mandates and making your project’s development that much smoother. We also follow other guidelines for municipalities in Ontario.

Contact us today and get a free consultation so you can begin streamlining your sewer capacity assessment immediately.