Commercial Water & Sewer

Sewer Use By-law

Hamilton’s Sewer Use By-law No. 14-090 (PDF, 2.61 MB) regulates the discharge of water and wastewater that enters the City’s sewage works by:

  • Establishing limits for common pollutants
  • Establishing a list of prohibited substances
  • Identifying requirements that users have to meet in order to discharge
  • Enabling the City to monitor and reduce the impact of spills
  • Enabling the City to monitor and control discharges

Sewer Use By-Law bannerSewer Use By-law Review
Please visit to complete a survey, provide feedback and to learn more about changes to the Sewer Use By-law and the construction dewatering program.

Discharge Guidelines

Hamilton’s Sewer Use By-law outlines sewer discharge guidelines for commercial, industrial, institutional and residential users that discharge wastewater to the city’s sewer works or have waste hauled to the sewer works for discharge. It is the user’s responsibility to ensure that their discharges meet the provisions specified in the by-law.

The sewer system collects discharges from commercial, industrial, institutional and residential sources and directs the flow to a Wastewater Treatment Plant.

If required by written notice, the owner or operator of any industrial, commercial or institutional property must complete the Sewer By-law Assessment Report (PDF, 2.4 MB).

  • It must be submitted, no later than 60 days after the written notice was delivered by email to [email protected].
  • Failure to submit the completed report by the due date, may result in enforcement action under the Sewer Use By-law.


Once you submit a Sewer Use By-law Assessment Report, the City  will notify you when a by-law officer will visit your property to assess the risk that each discharger poses to the sewer system. 

These inspections typically evaluate:

  • activities performed
  • chemicals and other products used or stored on-site
  • waste streams that are produced

During an inspection the officer may:

  • Make notes and take pictures
  • Interview staff
  • Obtain copies of documents and/or process or inventory logs
  • Collect samples

After the inspection the officer may make recommendations or issue directives, typically in writing, to correct any issues. The officer will also assess whether or not you need to obtain a Sewer Discharge Permit.

The City may enter any industrial, commercial, or institutional property at reasonable times to:

  • inspect the discharge of any matter into the sewer works
  • conduct tests and take samples

You may not stop the inspection. It is your responsibility to ensure the City has access for each facility.  If access does not currently exist,  we may ask you to install and maintain a suitable and safe monitoring access point such as a manhole in each sewer connection.


Anyone who does not follow the provisions under the Sewer Use By-law is guilty of an offence and upon conviction is subject to a fine up to $10,000 for a first offence, and $25,000 for any subsequent offence.

Where a corporation is convicted of an offense under the provisions of the Sewer Use By-law, the maximum are $50,000 for a first offence and $100,000 for any subsequent offence.


If a violation of one or more Sewer Use By-law provisions is identified, City staff will contact you to advise you of the non-compliance and you may receive a violation letter. If there are multiple violations, you may be subject to stricter enforcement.

A single violation of high severity may be deemed sufficient grounds for City staff to collect evidence and make formal charges under the by-law.


Refer to Schedule B of the Sewer Use By-law No. 14-090 (PDF, 2.61 MB) for the limits of sanitary sewer and combined sewer discharge.

Report a spill

Notify the City Spills Reporting Line immediately at 905-540-5188 if you spill matter or permit the spill of matter.

You will need to report:

  • the owner of the premises where the spill occurred
  • anyone who may be directly affected by the spill