Continuously discharging wastewater systems

The Wastewater Systems Effluent Regulations (the Regulations) apply to your wastewater system if: 

  • it collects an average daily volume of 100 cubic meters (m³) or more of influent in a given calendar year; and
  • it deposits effluent into water frequented by fish, or into a place that may enter water frequented by fish

The requirements set out below apply to owners and operators of continuously discharging wastewater systems that are subject to the Regulations. This refers to continuously discharging mechanical plants or outfalls with a hydraulic retention time less than five days.

Identification report

An identification report is required for each regulated wastewater system.

Information required

  • contact details of the owner, operator, contact person and address of the wastewater system
  • statement indicating that wastewater system is continuous and type of wastewater treatment (e.g. conventional activated sludge, rotating biological contactor, trickling filter, etc.)
  • statement indicating which entity owns or operates the wastewater system
  • information on the receiving environment (including latitude and longitude) at the locations below:
    • the final discharge point (i.e. the final sampling point location after the treatment process)
    • the point of entry for the final discharge point (where the effluent is released to the environment)
    • the overflow points for each combined and sanitary sewer (point where excess wastewater is deposited to the environment)

Change of information

If any information changes, the identification report must be updated within 45 days after the change.

Effluent quality standard

To comply with the Regulations, the effluent must meet specific conditions during discharge:

  • effluent must not be acutely lethal
  • limits on the concentrations of certain pollutants:
    • carbonaceous biochemical oxygen demand (CBOD)
    • suspended solids (SS)
    • total residual chlorine (TRC)
    • un-ionized ammonia (NH3)

 

Pollutant Limit Sample Report Results
Carbonaceous biochemical oxygen demand  Average ≤ 25 mg/L Yes Yes
Suspended solids Average ≤ 25 mg/L Yes Yes
Total residual chlorine  Average ≤ 0.02 mg/L Not required Not required
Unionized ammonia  Maximum < 1.25 mg/L Not required Not required

All samples must be tested by an accredited laboratory.  

Acute lethality testing must be done in accordance with:

  • procedure set out in Section five or six (Single or Multi-Concentration Test) of the Biological Test Method: Reference Method for Determining Acute Lethality of Effluents to Rainbow Trout (EPS 1/RM/13, Second Edition) or
  • above Method in conjunction with the Procedure for pH Stabilization During the Testing of Acute Lethality of Wastewater Effluent to Rainbow Trout (EPS 1/RM/50) (section 15)

For more information on acute lethality testing, consult this factsheet

Monitoring reports

Quarterly or annual monitoring reports are required for each wastewater system.

Information required

A statement that indicates that effluent was not deposited during the reporting period.

Alternatively, if effluent was deposited during certain months of the reporting period, a statement must be provided as well as:

  • number of days effluent was deposited
  • volume in cubic meters (m3) of effluent deposited
  • average CBOD in mg/L
  • average SS concentration in mg/L
  • for each sample for which a determination of acute lethality was made a statement that indicates:
    • sampling date
    • procedure used in Reference Method EPS 1/RM/13
    • if the pH stabilization procedure EPS 1/RM/50 was used
    • if sample was acutely lethal

Monitoring, sampling and reporting information for your specific size of wastewater system (refer to the applicable average daily effluent volume)

Average annual daily volume ≤ 2 500 m³ 

  • daily volume determination: continuous measure of influent or effluent volume or a measure of the daily rate of flow of influent or effluent in order to estimate the daily volume of effluent
  • sample type: composite or grab
  • sampling frequency (CBOD/SS): monthly but at least 10 days after any other sample
  • averaging period: quarterly averages for CBOD and SS 
  • reporting frequency: quarterly, within 45 days after the end of the reporting period (due February 14, May 15, August 14, November 14)
  • acute lethality testing:
    • not required for systems under 2500 m³ per day. If you do test acute lethality for any reason, results must be reported in quarterly monitoring reports

Average annual daily volume > 2 500 to ≤ 17 500 m³ 

  • daily volume determination: continuous measure of influent or effluent volume
  • sample type: composite
  • sampling frequency (CBOD/SS): every two weeks but at least seven days after any other sample
  • averaging period: quarterly averages of CBOD and SS 
  • reporting frequency: quarterly, within 45 days after the end of the quarter (due February 14, May 15, August 14, November 14)
  • acute lethality testing:
    • normal sampling frequency: quarterly but at least 60 days after any other sample
    • number of passes to reduce sampling frequency: four consecutive quarters where samples were determinated not to be acute lethal
    • reduced sampling frequency: annually but at least six months after any other sample
    • sampling frequency after a test failure: twice a month until three consecutive passes, then sampling frequency goes back to quarterly sampling

Average annual daily volume > 17 500 to ≤ 50 000 m³ 

  • daily volume determination: continuous measure of influent or effluent volume.
  • sample type: composite
  • sampling frequency (CBOD/SS): weekly but at least five days after any other sample
  • averaging period: calculate monthly averages of CBOD and SS 
  • reporting frequency: quarterly, within 45 days after the end of the quarter (due February 14, May 15, August 14, November 14)
  • acute lethality testing:
    • normal sampling frequency: quarterly but at least 60 days after any other sample
    • number of passes to reduce sampling frequency: four consecutive quarters where samples were determinated not to be acutely lethal
    • reduced sampling frequency: annually but at least six months after any other sample
    • sampling frequency after a test failure: twice a month until three consecutive passes, then sampling frequency goes back to quarterly sampling

Average annual daily volume > 50 000 m³ 

  • daily volume determination: continuous measure of influent or effluent volume.
  • sample type: composite
  • sampling frequency (CBOD/SS): three days per week but at least one day after any other sample
  • averaging period: calculate monthly averages of CBOD and SS 
  • reporting frequency: quarterly, within 45 days after the end of the quarter (due February 14, May 15, August 14, November 14)
  • acute lethality testing:
    • normal sampling frequency: monthly but at least 21 days after any other sample
    • number of passes to reduce sampling frequency: 12 consecutive months where samples were determined not to be acutely lethal
    • reduced sampling frequency: quarterly but at least 60 days after any other sample
    • sampling frequency after a test failure: twice a month until three consecutive passes, then sampling frequency goes back to monthly sampling

Combined sewer overflows 

Owners or operators of a wastewater system with at least one combined sewer overflow point must record overflows and submit annual reports.  

For each deposit day, record:

  • date of deposit via overflow point
  • duration or estimated duration of deposit in hours
  • daily volume or estimated volume in cubic meters (m³)

For each deposit month, record:

  • volume or estimated volume of effluent deposited via overflow point for the month in cubic meters (m3) number of days effluent was deposited in the month
  • daily volume or estimated volume in cubic meters (m³)

Information required in report

For the month of overflow:

  • volume or estimated volume of effluent deposited via overflow point for the month in cubic meters (m³)
  • number of days effluent was deposited in the month

Indicate the months where no deposit occurred.

Reports are due annually February 15.

Temporary authorization to deposit un-ionized ammonia 

Owners or operators can apply for a temporary authorization to deposit un-ionized ammonia if if it is determined that their wastewater system is depositing acutely lethal effluent due to un-ionized ammonia.

Initial application should be made within 30 days after the determination is made.

Authorization is issued for a three-year period. To extend the authorization, a new application must be made 90 days before the expiry of the existing authorization.

For more information, consult this factsheet

Temporary bypass authorization 

Temporary bypass authorizations can be issued if the owner or operator needs to bypass one or more treatment processes for:

  • necessary construction or maintenance work at the wastewater treatment plant
  • for anticipated events out of control of the owner or operator

Application should be made at least 45 days before the bypass.

For more information, consult this factsheet

Contact us

If you require further assistance or have any questions, please contact Environment and Climate Change Canada at eu-ww@ec.gc.ca .

Disclaimer

This information does not in any way supersede or modify the Wastewater Systems Effluent Regulations or the Fisheries Act, or offer any legal interpretation of those Regulations or Act. Where there are any inconsistencies between this information and the Regulations or Act, the Regulations or Act take precedence, respectively.  A copy of the Wastewater Systems Effluent Regulations is available for your reference.   

 

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