| #Q001 | administrative | unknown | mandatory | Implementation Applicability | wastewater, other | The design criteria for manufactured treatment devices (MTDs) will be applied to all Stormwater Management Report submissions to the City. | | high |
| #Q002 | administrative | unknown | mandatory | Mandatory Implementation Date | wastewater, other | As of April 1, 2023, only the new design criteria will be applied to Stormwater Management Reports submitted in connection with new development applications received by the City and dated on or after April 1, 2023. | Applicable to new development applications dated on or after April 1, 2023 | high |
| #Q003 | design | treatment | mandatory | Acceptable MTD Types for Water Quality Control | wastewater, other | Only the following types of MTDs, as classified and defined by Environmental Technology Verification (ETV) Canada (Bulletin CETV 2022-02-0001), can be proposed to meet water quality control targets (i.e., suspended solids removal) of the City’s Wet Weather Flow Management Guideline: Oil-grit separator (OGS) devices... Filter devices... | When proposed to meet water quality control targets | high |
| #Q004 | prohibition | treatment | mandatory | Other MTD Types Restriction | wastewater, other | MTDs (other than OGSs and filter devices), including inlet pre-treatment devices (e.g. catch basin inserts/retrofit installations), may only be used as best management practices to protect or optimize operations and maintenance of downstream drainage or stormwater management infrastructure. These MTDs will not be credited for suspended solids removal for water quality compliance. | | high |
| #Q005 | design | treatment | mandatory | OGS Testing Protocol | wastewater, other | The OGS will be laboratory tested in accordance with the Procedure for Laboratory Testing of Oil-Grit Separators (TRCA/CETV Program) testing protocol and will have current and valid ISO14034: Environmental Technology Verification (ETV). | When OGS devices are proposed | high |
| #Q006 | design | treatment | mandatory | OGS Design Treatment Flows Estimation | wastewater, other | Design treatment flows to the OGS will be estimated based on the Rational Method using design rainfall intensities that correspond to percent average annual rainfall volumes. | | high |
| #Q007 | design | treatment | mandatory | OGS Sizing Requirement | wastewater, other | The OGS will be sized to treat design treatment flows ensuring the minimum capture of 90 percent average annual rainfall volume from its contributing drainage area(s), assuming no upstream attenuation of design treatment flows. | | high |
| #Q008 | design | treatment | mandatory | OGS Performance Compliance | wastewater, other | The OGS performance will demonstrate overall site-wide compliance with applicable suspended solids removal targets as a standalone treatment device or as part of a larger stormwater management plan. | | high |
| #Q009 | design | treatment | mandatory | OGS Annual Suspended Solids Removal Performance | wastewater, other | The annual suspended solids removal performance claimed for the OGS will be based on the average annual rainfall volume-weighted removal efficiency calculated for design surface loading rates (SLR) from all particle sizes of the ETV-tested particle size distribution. | | high |
| #Q010 | design | treatment | mandatory | OGS Performance Evaluation Methodology | wastewater, other | The performance evaluation methodology will: Calculate removal efficiencies for all design SLRs based on the full range of design treatment flows, divided by the OGS surface area. Linearly interpolate the verified removal efficiency for design SLRs, which fall between tested SLRs. Assume a removal efficiency which is identical to the verified removal efficiency for the lowest tested SLR, when the design SLR is less than the lowest tested SLR. Assume a removal efficiency of zero (0) for any incremental increase in design SLR, when the design SLR is greater than the highest tested SLR. | | high |
| #Q011 | design | treatment | mandatory | OGS Device Scaling Requirements | wastewater, other | The selected model for the OGS device will meet all scaling principles relative to the tested model, as per the applicable testing protocol, including but not limited to: The claimed sediment removal efficiencies for similar manufactured treatment devices (MTDs) are the same or lower than the tested MTD at identical surface loading rates; and The similar MTD is scaled geometrically proportional to the tested unit in all inside dimensions of length and width and a minimum of 85 per cent proportional in depth. | | high |
| #Q012 | prohibition | treatment | mandatory | MTDs Installed in Series Removal Credit Prohibition | wastewater, other | Where two or more MTDs are proposed to be installed in series, no additional removal credit may be assumed beyond the removal efficiency of the MTD with the highest removal efficiency. | When two or more MTDs are installed in series | high |
| #Q013 | design | treatment | guidance | OGS Off-line Installation Permission | wastewater, other | The OGS may be installed off-line when the hydraulic bypass capacity of the upstream flow-diversion structure is greater than the full pipe capacity of the incoming sewer, minus the design treatment flow required for 90 per cent average annual rainfall volume capture. | When hydraulic bypass capacity of upstream flow-diversion structure is greater than full pipe capacity minus design treatment flow required for 90% average annual rainfall volume capture | high |
| #Q014 | design | treatment | guidance | OGS In-line Installation Permission (Capacity Criteria) | wastewater, other | The OGS may be installed in-line when the hydraulic bypass capacity of the internal bypass structure is greater than the full pipe capacity of the inlet sewer, minus the design treatment flow required for 90 per cent average annual rainfall volume capture. | When hydraulic bypass capacity of internal bypass structure is greater than full pipe capacity minus design treatment flow required for 90% average annual rainfall volume capture | high |
| #Q015 | design | treatment | guidance | OGS In-line Installation Permission (Scour Criteria) | wastewater, other | The OGS may be installed in-line when the hydraulic bypass capacity of the internal bypass structure is greater than the full pipe capacity of the inlet sewer, minus the maximum tested scour flow rate, and the total suspended solids (TSS) effluent concentration for the maximum tested scour flow rate does not exceed 25 mg/L (Canadian Environmental Quality Guidelines for High Flow) above the tested background influent concentration level. | When hydraulic bypass capacity meets criteria and TSS effluent for maximum tested scour flow does not exceed 25 mg/L above background influent | high |
| #Q016 | design | operational | mandatory | OGS Maintenance Target Sizing | wastewater, other | The OGS will be sized to target a maintenance interval of one year based on the accumulated annual sediment loading (average event mean concentration of 200 mg/L; sediment wet density of 1230 g/m3) generated from the average annual precipitation volume (840 mm). | | high |
| #Q017 | design | treatment | mandatory | Filter Device Testing and Verification Requirements | wastewater, other | The filter device will meet any one of the following conditions: 1. The device will have Washington State Technology Assessment Protocol-Ecology (TAPE) certification for approved technologies with General Use Level Designation (GULD) and have field testing conducted in accordance with the TAPE protocol, where a minimum of three rainfall events have been captured that exceed the design rainfall intensity and depth corresponding to 90 per cent of the average annual rainfall volume. 2. The device will be field-tested in accordance with Washington State TAPE protocol and will have current and valid ISO 14034:ETV verification, where a minimum of three rainfall events have been captured that exceed the design rainfall intensity and depth corresponding to 90 per cent of the average annual rainfall volume. | When filter devices are proposed | high |
| #Q018 | design | treatment | mandatory | Filter Device Design Treatment Flow Estimation | wastewater, other | The design treatment flow to the filter device will be estimated based on the Rational Method using the design rainfall intensity required for 90 per cent average annual rainfall volume capture. | | high |
| #Q019 | design | treatment | mandatory | Filter Device Sizing Compliance | wastewater, other | The filter device will be sized to treat the design treatment flow in order to demonstrate compliance with site-wide water quality control targets, assuming no upstream attenuation of design treatment flows. | | high |
| #Q020 | design | treatment | mandatory | Filter Device Claimed Suspended Solids Removal | wastewater, other | The suspended solids removal claimed from the filter device will be based on the tested average removal efficiency of suspended solids up to a 95 per cent confidence interval for the design treatment flow. | | high |
| #Q021 | design | treatment | guidance | Filter Device Scaling Application | wastewater, other | The suspended solids removal rate determined for the tested filter device may be applied to other model sizes of that filter device provided that appropriate scaling principles as per the applicable testing protocol are applied, including but not limited to: depth of media, composition of media and gradation of media; the ratio of the design treatment flow rate to effective filtration treatment area (filter surface area) is the same or less than the tested filter device; the ratio of effective sedimentation treatment area to effective filtration treatment area is the same or greater than the tested filter device; and, the ratio of wet volume to effective filtration treatment area is the same or greater than the tested filter device. | When applying tested suspended solids removal rates to other model sizes of the filter device | high |
| #Q022 | design | treatment | guidance | Filter Device Off-line Installation Permission | wastewater, other | The filter device may be installed off-line when the hydraulic bypass capacity of the upstream flow-diversion structure is greater than the full pipe capacity of the incoming sewer, minus the design treatment flow required for 90 per cent average annual rainfall volume capture. | When hydraulic bypass capacity conditions are met | high |
| #Q023 | design | treatment | guidance | Filter Device In-line Installation Permission | wastewater, other | The filter device may be installed in-line when the hydraulic bypass capacity of the internal bypass structure is greater than the full pipe capacity of the inlet sewer, minus the design treatment flow required for 90 per cent average annual rainfall volume capture. | When internal bypass capacity conditions are met | high |
| #Q024 | design | operational | mandatory | Filter Device Maintenance Target Sizing | wastewater, other | The filter device will be sized to target a maintenance interval of one year. | | high |
| #Q025 | reporting | reporting | mandatory | Stormwater Management Report Submission Requirements | wastewater, other | Where manufactured treatment devices (MTDs) are proposed in a stormwater management plan, the following minimum MTD-specific data and information will be attached, as part of the Stormwater Management Report submission for City review and acceptance: Manufactured Treatment Device Summary Form, including supporting documentation. | When MTDs are proposed in a stormwater management plan | high |
| #Q026 | reporting | operational | mandatory | Operations and Maintenance Manual Submission | wastewater, other | Operations and Maintenance Manual – For MTDs proposed within public property, content must include, but not be limited to, the following: Asset Management... Operations and Maintenance... | For MTDs proposed within public property | high |
| #Q027 | design | treatment | guidance | Sub-catchment Delineation for Large Sites | wastewater, other | For larger sites greater than 2 hectares, applicants may delineate smaller sub-catchment areas draining to MTDs and apply the Rational Method for sizing. | For larger sites greater than 2 hectares | high |
| #Q028 | prohibition | treatment | mandatory | Prohibition of Hydrological Modelling for Sizing MTDs | wastewater, other | Hydrological modelling or detention routing will not be accepted for the sizing of specific MTDs but may be used for modelling/sizing of other stormwater management features. | | high |
| #Q029 | design | treatment | mandatory | Third-Party Calculation Tools Verification | wastewater, other | Applicants are responsible for ensuring that any third-party calculation tools (e.g., TRCA-STEPP OGS Review Sheet) proposed for use in performance evaluation, sizing, and decision-making, meet all requirements of the Design Criteria, and verified for accuracy of data and methodology. | | high |
| #Q030 | administrative | treatment | mandatory | TAPE Conditional Check | wastewater, other | the Design Criteria requires applicants to conduct a conditional check of TAPE tested rainfall events to ensure results from TAPE certifications are applicable to the City’s climate. | | high |
| #Q031 | prohibition | treatment | mandatory | ISO14034 ETV Standalone Prohibitions | wastewater, other | Performance claims of MTDs (including pre-treatment devices) with ISO14034: ETV verification statements alone will not be recognized for stormwater quality control. | | high |
| #Q032 | administrative | unknown | mandatory | Continuation of WWFMG Requirements | wastewater | All other requirements of the WWFMG will continue to apply. | All stormwater management plans not explicitly replaced by these MTD criteria | high |
| #Q033 | administrative | operational | mandatory | City Right to Reject MTDs on City Property | wastewater | The City reserves the right to reject MTDs proposed on City property based on site-specific operational and asset management constraints. | When MTDs are proposed for installation on City property | high |
| #Q034 | administrative | operational | mandatory | Professional Engineer Responsibility for MTD Selection | wastewater | The selection of any MTD in a Stormwater Management Report is solely at the discretion of the professional engineer responsible for the report’s preparation, on behalf of their client/applicant and subject to compliance with Wet Weather Flow Management Guidelines (2006) and the Design Criteria for MTDs. | Preparation of Stormwater Management Reports | high |
| #Q035 | administrative | unknown | mandatory | Specific Applicability Triggers | wastewater, other | The design criteria for manufactured treatment devices (MTDs) apply to all Stormwater Management (SWM) Reports submitted to the City as part of Terms of References for new development applications, applications for storm connection exemptions under the Toronto Municipal Code (Chapter 681 – Sewers), and applications requiring Environmental Compliance Approvals (ECA) under the applicable approvals framework from the Ministry of Environment, Conservation and Parks (MECP). | All Stormwater Management Report submissions | high |
| #Q036 | prohibition | treatment | mandatory | Prohibition of Default OGS Removal Credit | wastewater, other | A default 50% TSS removal credit for OGS devices will no longer be applicable. | When OGS devices are proposed | high |
| #Q037 | reporting | operational | mandatory | Detailed O&M Manual Requirements for Public Property | wastewater, other | Operations and Maintenance Manual – For MTDs proposed within public property, content must include, but not be limited to, the following: Asset Management: Identification description, including dimensions; Expected life-cycle period; Inspection frequency, including operating assumptions and failure modes; Maintenance frequency, including rehab and refurbishment; Component and materials list and sourcing (e.g. local, overseas); Complete replacement cost; Annual operations and maintenance component and materials cost; Personnel requirements for inspection and maintenance e.g. number of staff, certification, labour hours; Health and safety considerations (e.g. confined space requirements, materials storage and handling). Operations and Maintenance: Accessibility (e.g. access dimensions, ease of access, confined space); Minimum setback and vertical clearance requirement (for access, equipment laydown, use, etc.); Requirements for water supply access and use; Inspection and maintenance equipment list; Step-by-step inspection procedures; Step-by-step maintenance procedures. | For MTDs proposed within public property | high |
| #Q038 | design | operational | mandatory | Filter Maintenance Interval Determination Basis | wastewater, other | the City will rely on the proposed filter device to be designed for a 1-year maintenance interval, as determined and recommended by the manufacturer. | When filter devices are proposed | high |
| #Q039 | administrative | unknown | guidance | Phase-in Period Optionality | wastewater, other | During this phase-in period, new development applications with a submission date up to March 31, 2023 can use either the new design criteria for MTDs or Sections 2.2.2.2 (3) and Appendix B of the Wet Weather Flow Management Guideline. | New development applications with a submission date up to March 31, 2023 | high |
| #Q040 | administrative | unknown | mandatory | Replacement of Previous OGS Guidance | wastewater, other | The design criteria for MTDs replace the guidance on oil-grit separators (OGSs), as previously detailed in the City of Toronto’s Wet Weather Flow Management Guidelines (WWFMG). | | high |