Apply for a Wastewater discharge permit

Last updated March 23, 2023

Is it possible your establishment could discharge wastewater into the sewage system or a watercourse within the Montréal Urban Agglomeration? Before doing so, you must meet certain requirements and obtain a permit.

Permits vary depending on the type of facility involved and the type of discharge from the facility. We have identified three cases. In addition, if an accidental discharge (a spill) occurs, you must report it.

Permit to discharge

Industrial establishments

The following are examples of items that must be documented to submit a permit application:

  • Monitoring of processes that generate wastewater
  • Monitoring of source control devices (flow and pollution discharge reduction)
  • Measures to control accidental spills
  • Maintenance operation on treatment systems
  • Record keeping of treatment system operations and maintenance
  • Monitoring program, periodic analysis.

In certain cases, an approval is required rather than a permit. If in doubt, contact us to confirm what applies to your situation.

Apply for a permit

  • Complete the form (see the “Documents” section on this page). 
  • Send it to the Service de l’environnement as directed. 

Engineering documents submitted with the application must be authenticated by a professional engineer.

Issuance of the permit

If your application meets all these requirements, your permit will typically be issued within 75 working days.

You must receive your permit prior to beginning the work.

Dental offices

An amalgam separator is required to limit the release of mercury into the sewage system and avoid environmental contamination.

Apply for a permit

Attach the two most recent proofs of maintenance of the amalgam separator (proof of waste disposal, invoices, work orders or other) to your application.

Businesses that discharge sludge from septic tanks or chemical toilets

An annual permit is required to discharge their contents. In addition to the cost of this permit, there is a fee for each discharge. Fees are calculated based on the volume of the tank and the moisture level of the sludge.

Apply for a permit

  • Complete the application (see the “Documents” section on this page).
  • Attach a copy of the registration certificate and payment of the permit for each tank (consult the tariff by-law to determine the cost).
  • Send it to the Service de l’environnement as directed.

Declaration of a accidental discharge

Regardless of the type of discharge, it must be reported immediately. 

Declare the discharge

  • Report the discharge to 514 280-4330.
  • Complete the declaration (see the “Documents” section on this page).

Send to the Service de l’environnement a supplementary statement during the following 15 days, specifying the causes of the discharge and the corrective measures implemented.


Request a permit or a make declaration

Service de l'environnement


Application for an annual discharge permit (Sludge)

827 Boulevard Crémazie Est, suite 302
Montréal, QC H2M 2T8

Payment methods

  • Certified cheque to the order of “Ville de Montréal”
  • Postal money order to the order of “Ville de Montréal”
  • Bank draft