Steps in the Study Process

During the Study

As part of the study, a complete and thorough assessment of the existing sewer system and overland drainage systems will be completed. This work will help to identify what is at risk during a storm event.

The study will follow the steps in the Municipal Class Environmental Assessment process for planning and designing municipal infrastructure. The typical process includes:

Our first step is to collect data. Previously, we have also looked for input from an online survey to determine the source of flooding from private properties.

The next step is an internal technical assessment, which includes

  • Reviewing flooding history
  • Analyzing sewer data records
  • Surveying catchbasins, roof downspout connections, low-lying areas
  • Monitoring water flow
  • Determining where repeated flooding occurs
  • Analyzing the causes of flooding

Recommended infrastructure solutions often include, but are not limited to:

Drainage Measures

Example of a high-capacity curb inlet
Limiting the amount of water that can enter a storm sewer by using catchbasin inlet control.
Example of infrastructure on the road that helps divert surface drainage
Diverting surface drainage by redirecting water away from low-lying areas with no direct outlet.
Example of multiple high-capacity inlets
Increasing the number of catchbasins in order to capture more stormwater flow.
Example of a storm interceptor
Sealing sanitary manhole covers to prevent water from entering the sanitary system in low-lying areas.

Sewer Upgrades

Workers installing new sewer.
Adding new sewers.
An oversized pipe on a street, with a traffic cone in front of it for comparison
Replacing existing sewers with larger pipes.

Stormwater Control

Bluffer's Park wet pond featuring a flow balancing system
Using wet ponds to collect and store runoff from rain and melted snow, improving the quality of water released back into creeks and rivers downstream.
An example of a bioretention unit in the middle of a grassy area
Using bioretention units to remove a wide range of pollutants, reduce peak runoff rates and increase stormwater infiltration.

Underground Storage

Diagram of an underground storage tank
Controlling the rate of inflowing sanitary or stormwater through temporary detention and slow release to the receiving sewer, reducing the potential for flooding.
  • Online survey
  • Public drop-in events
  • Stakeholder meetings
  • Conceptual design
  • Report
  • 30-day public review

After the Study

From Study to Construction

Once a study is complete, the recommended basement flooding projects are sequenced into a five-year project list which is presented on an annual basis to City Council.

Projects are prioritized and scheduled to protect the greatest number of properties as soon as possible, within approved budgets and coordinated with other construction work, as per Council-approved criteria. The length and type of construction will vary depending on the type of projects being implemented.

Prioritization of Construction Projects

Not all recommended projects from the study will proceed immediately to the design and construction stage. Projects are prioritized for implementation based on a City Council-adopted $68,000 cost-per-benefitting-property threshold. Projects with a cost less than $68,000 per property at the study stage and preliminary design stage proceed to construction.

Projects that exceed the $68,00 cost-per-benefitting-property threshold will not be included in the five-year project list to undergo preliminary design. They will be moved into the State of Good Repair’s long-term capital plan.