From LID SWM Planning and Design Guide
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The following, comprehensive list is presented as a basis for discussion between regulatory authorities and design practitioners.

Site Description[edit]

  • Location (key plan, municipal address, nearest roads, watershed and subwatershed);
  • Existing Conditions (land use on site and surrounding areas);
  • Natural Heritage features;
  • Proposed Conditions;
  • Drainage Area (for the site, tributary and watershed);
  • Watercourses, wetlands present on site, and type (permanent or intermittent);
  • Drainage patterns and ultimate drainage location/outfall;

Background Information[edit]

  • Pre-submission meeting verification;
  • Reports from pre-consultation with MOECP and other agencies (especially related LID credits);
  • Watershed plans;
  • Sub-Watershed plans;
  • Master drainage plans (MDPs);
  • Other previous reports and relevant SWM requirements;
  • Existing models;
  • Geotechnical report;
  • Hydrogeological report;

Figures and drawings[edit]

  • Location plan in the report;
  • Key plan on the drawings;
  • All watercourses and names of watercourses shown on all figures and drawings;
  • Pre-development and post-development drainage plans for hydrologic model(s) which include:
    • Existing contours;
    • Drainage direction (minor and major system);
    • Catchments ID's;
    • Areas and imperviousness;
    • Uncontrolled areas;
    • 100 year capture;
    • Site outlets; and
    • LID facility location and associated tributary areas;
  • Model schematics;
  • Storm drainage, grading and general servicing plans;
  • LID practice design drawings and details;
  • Erosion and sediment control plans;
Parameter Plan Detail Profile Description
Location x Area extent shown on plan view (bump-outs, municipal reserves, private lots, parks)
Surface area x Outlined on plan view drawings and stated in report
Inlet x x shown on plan view and typical details provided (curb cuts, flow spreader, ribbon curb)
Materials x Materials specs (soil, drainage layer), depth, hydraulic conductivity, porosity
Vegetation x x Planting plan and vegetation details (species, mature density, succession plan)
Outlet x x x Underdrain spec and slope, spill elevation, catch basin type and grate, weir type and location, inlet control device details
Catchment x Delineated catchment area directed to bioretention facility
Subsurface materials x Layer order (filter, reservoir, choker course, geotextiles (if using)) and specifications (gradation, hydraulic conductivity, void space)
Depth x x Depth of each layer, reservoir retention depth (if applicable), surface ponding depth (if applicable)
Slope x x Sub-base slope and surface slope
Flow Arrows x From contributing area and overflow route
Water depth x Ponding depth and water surface elevation during design storm and maximum prior to overflow
Inundation x Extent of of inundation during design storms
Erosion control x x Located at inlet, outlet if overland spill

Design Information[edit]

  • Consistent hydrology modelling to be utilized for each development application and/or consistent with MESP/MSP/Studies.
  • Supporting information has been included for all modelling parameters and calculations.
  • Stage-Storage-Discharge calculations provided for each LID facility including design information on control and emergency overflow weirs.
  • Flow and storage summary tables provided which reference the associated drainage area, catchment ID, outlet(s) and differentiate between controlled and uncontrolled areas.
  • Identify and show seasonal high groundwater levels in report and on drawings;
  • Per MOECC SWM manual, 2003 (i.e. Drainage area, required volume, slopes, forebay, etc.);
  • The SWM report and drawings are to include a table summarizing required storage, provided storage and associated elevation and flow for the permanent pool, 25mm (extended detention), and 2 through 100 year return period storm events where applicable for each facility;
  • An operations and maintenance manual (includings a maintenance schedule) should be included in the SWM Report for all LID facilities in accordance with municipal requirements;
  • Complete information on proposed manufactured treatment devices is to be provided including current status under ETV protocols;

Quantity control[edit]

  • Runoff coefficient or imperviousness calculations;
  • Analysis using appropriate storm distributions;
  • Pre-development peak flow (m³/s);
  • Post-development uncontrolled peak flow (m³/s);
  • Post-development controlled peak flow (m³/s);
  • LID Facility Type;
  • Stage – Storage – Discharge Table;
  • Outlet design and calculations;
  • Total storage required (m3);
  • Total storage provided (m3);
  • Table comparing provided versus required;
  • Overland flow conveyance and design;
  • External drainage conveyance (100 year and Regional);

Quality control[edit]

  • Level of protection;
  • Drainage area to facility in hectares;
  • Percentage impervious – total and directly connected areas;
  • SWM facility monitoring and maintenance requirements;

Hazard land management[edit]

  • Regional event and 1:100 year flood lines under existing and proposed conditions shown on appropriate plan drawings;
  • Valley top of bank, stream erosion, steep slope allowances and meanderbelt assessed (confined stream systems only);
  • Wetlands and required setbacks determined and identified on plans;
  • Meanderbelt assessment and/or setback determined and identified on plans;
  • Wave uprush and/or wind setup elevations calculated;
  • “Limit of development” shown on plans;
  • Survey and floodplain mapping submitted (see below);
  • Hydraulic modelling and analysis including digital files;


  • Upon approval of the SWM design, a digital copy of the stormwater drainage plan is to be submitted including the location and size of the SWM facility in GIS format;

Floodplain mapping and documentation minimum requirements[edit]

  1. Hydraulic sections with regulated floodplain elevations and cross-section identification;
  2. Existing and proposed floodplain delineation;
  3. Topographic information including elevations and contours;
  4. Conveyance structures including dams, bridges, culverts and weirs;
  5. Man-made structures as applicable including buildings, roads, railways and trails;
  6. Natural reservoirs or natural storage areas;
  7. Spills analysis as applicable;
  8. Cut/fill analysis in the regulated area as applicable;
  9. Natural features such as watercourses and wetlands;
  10. Floodplain mapping and supporting documentation signed and stamped by a P.Eng.

Survey documentation minimum requirements[edit]

For any submission which contains drawings or figures that present survey information, the following list of minimum requirements must be included:

  1. Document with text descriptor identifying overall approach and methodology;
  2. Drawing/Figure Title;
  3. Date, and Revision List where applicable;
  4. Legible Scale and North direction arrow;
  5. OLS Surveyor Name and contact information, as applicable;
  6. Geodetic benchmark data used in survey, as applicable;
  7. Available survey data for topographic surface, structures, features, etc.;
  8. Structures invert, obvert elevations and dimensions as applicable;
  9. Bathymetry as applicable;
  10. Documentation to support reported data accuracy;
  11. Methodology for survey data collected i.e. Total Station, GIS, Rod and Level;
  12. Photo log of structures survey including upstream, downstream and structures completed with structure survey;
  13. Drawings and / or figures to be submitted both electronically and in hard copy as requested;
  14. Digital copy of the survey data when applicable; and
  15. Submission components to be stamped and signed by an OLS, P.Eng. or C.E.T. as relevant.

Geospatial data submission minimum requirements[edit]

For a submission which contain drawings, figures, reports, modelling and / or memos that present geospatial information and its analysis; the following list of minimum requirements must be included:

  1. Text summary identifying methodology and software used in geospatial analysis;
  2. Acquisition type i.e. LIDAR, orthophotos, etc.;
  3. Date of data acquisition;
  4. Name of supplier of digital information and their contact information;
  5. Quality Assurance / Quality Control methodology for geo-spatial as applicable;
  6. Data Co-ordinate system;
  7. Data Projection;
  8. Data Horizontal and vertical resolution;
  9. Data Accuracy for each axis as applicable;
  10. Description of grid resolution;
  11. Drawing and / or figure scale identified as applicable;
  12. Contours presented at minimum 0.5 m increments;
  13. Orthophoto Elevation Data i.e. study area break lines and DTM points;
  14. LIDAR Elevation Data i.e. study area point cloud (as applicable);
  15. Digital Elevation Model (DEM) as applicable;
  16. Description of modifications to surface including adjustments to the TIN from other sources (i.e. surveyed culverts, new infrastructure invert and obvert elevations etc.);
  17. Flood limit data;
  18. Drawings and / or figures to be submitted both electronically and in hard copy when requested;
  19. In modelling files and documentation to maintain existing watercourse naming conventions were applicable;
  20. Projected Co-ordinate system: Preferably NAD 1983 UTM Zone 17N;
  21. Accepted Original Geospatial Data file format: File Geodatabase or Shapefiles; and
  22. Submission components to be stamped and signed by an OLS, P.Eng. or C.E.T. as relevant.