Exterior Storm Drain Disconnection

What does an exterior storm drain do?

Exterior storm drains are typically a catch basin or an inlet grate that collects rainwater from surfaces like reverse-grade driveway, basement walk-out patios, and stairwells. They are designed to direct stormwater away from your home.

Why is it important to disconnect the exterior storm drain from the wastewater system?

It is important that exterior storm drains on private property are not connected to the wastewater sewer system. Instead, they should be redirected to a sump pump or a gravity drainage feature that discharges rainwater outside the home and overland, away from the foundation. This helps reduce the risk of basement flooding during rain events and improves the overall performance of the Region’s wastewater sewer system.

When storm drains are improperly connected to the wastewater sewer, they can overload the system during rainfall, leading to backups and flooding. These connections are a major source of inflow and infiltration, which can strain infrastructure and increase treatment costs.

Financial support

Halton Region’s subsidy for the Exterior Storm Drain Disconnection subsidy covers 100% of costs incurred for materials and labour charged to disconnect the exterior storm drain, up to a maximum of $6,500.

Downspout disconnection provides additional protection against basement flooding while reducing strain on your sump pump. For optimal performance of your sump pump, disconnecting your downspouts is required. Please see our Downspout Disconnection subsidy for more details on how to qualify for this subsidy.

Eligibility criteria

To qualify for this subsidy, all of the following conditions must be met. The home where the work is completed must:

• be located within Halton Region; and
• be connected to Halton Region’s municipal wastewater (sewer) system (homes on septic systems are not eligible); and
• applications must be submitted within one year after the work has been completed.

Halton Region requires proof that the exterior storm drain is currently connected to the wastewater system. This proof must be provided from one of two sources:

• a Household Drainage Survey, where eligible; or
• a plumbing or drainage assessment completed by a licensed plumber or qualified drainage contractor.

Additional criterion: Disconnecting and redirecting below-grade exterior storm drains (such as reverse driveways, stairwells, patios) away from the wastewater system.

• Eligible where these drains are connected to the wastewater system.
• Discharge must be directed to an appropriate surface location in compliance with the local municipal drainage by-laws.

Application requirements

Your application must include:

• a completed and signed Basement Flooding Prevention Subsidy Program application form (PDF file)
• a completed and signed Basement Flooding Prevention Subsidy Program waiver form (PDF file)
• an itemized invoice, paid in full, specifically listing any materials and labour and identifying specifics of each component of the work:
  • exterior storm drain disconnection and sump pump installation
  • installation of backup system
  • plumbing assessment (if applicable)
  • CCTV videos
  • permit costs
• a copy of the issued permit (if new sump pump is installed – drainage engineering for gravity outlet) required by, and obtained from your Local Municipality (City of Burlington ,Town of Halton Hills, Town of Milton or Town of Oakville)
• confirmation and proof that the building permit has passed the final inspection and has been signed off by the applicable Local Municipal building inspector (City of Burlington Town of Halton Hills, Town of Milton or Town of Oakville)
• contractor confirmation of a pre-existing connection between the exterior storm drain(s) and the wastewater system, demonstrated through Household Drainage Survey results, pre-construction photos, closed-circuit television (CCTV) footage, or dye test results
• confirmation that the exterior storm drain(s) connection to the wastewater system was disconnected by the contractor and in accordance with program requirements, demonstrated through post-construction photos, closed-circuit television (CCTV) footage, or dye test results

Water powered backup sump pumps are not eligible for the Weeping Tile Disconnection and Sump Pump Installation Subsidy or the Exterior Storm Drain Disconnection Subsidy. They pose risks to the municipal drinking water supply if not properly installed and maintained as required by Drinking Water System By-law 71-19 (PDF file).

Apply to the program

1. Download the Basement Flooding Prevention Subsidy Program application form (PDF file) and the Basement Flooding Prevention Subsidy Program waiver form (PDF file).
2. Submit completed Application Form and Waiver along with the required documentation, electronically. Ensure submission completeness by following the Check List included on the Application Form. Errors or omissions will delay approval of the subsidy.
3. Scan and email your completed submission to basementfloodingsubsidy@halton.ca  .
4. Upload larger files, such as CCTV video, to our online Dropbox platform (external link) .

A subsidy cheque will be mailed 4-6 weeks from the date we receive a completed application for an eligible project with all required documentation.

For assistance with using Dropbox

Please see our Dropbox example image (image file)  or review the instructions below:

Additional options for subsidy submission include the following:

• Mail to:
  Halton Region Public Works
  c/o Water and Wastewater Program Ambassador
  Woodlands Operations Centre
  1179 Bronte Road, Oakville, ON L6M 4G3
• Drop off in person: 
  Place submission in the black mail box located in front of the sliding doors at the main entrance to Halton Regional Centre, located at 1151 Bronte Road, Oakville (Google Maps link)  

Note: Woodlands Operations Centre is currently closed to the public.