STORM WATER MANAGEMENT REPORT

A Storm Water Management (SWM) Report should be prepared by a qualified civil/water resources engineering consultant. The Storm Water Management (SWM) Report must be stamped, dated, and signed by a Professional Engineer (P.Eng.) licensed in Ontario.

The objective of a Storm Water Management (SWM) Report is to evaluate the effects of a proposed development on the storm water and drainage system, and to recommend how to manage the rainwater/snowmelt for the proposed development, consistent with the municipal requirements for storm drainage and also meet conservation authority and provincial regulations for storm water management.

A Storm Water Management (SWM) Report may be required in support of the following development application types:

• Official Plan Amendment
• Zoning By-law Amendment
• Draft Plan of Subdivision / Condominium
• Site Plan Control
• Consent to Sever
• Minor Variance

The Storm Water Management (SWM) Report must provide sufficient engineering information to allow for the necessary review and acceptance of the proposed storm water management schemes in principle and should address, but not be limited to, the following:

• Identify and describe the site location, area, pre-development and post-development conditions for storm drainage, etc.;
• Identify the inlets from upstream and outlets to downstream for the minor and major systems, including overland storm water flow routes;
• Identify all internal and external storm water drainage areas under existing and future development conditions for minor and major storm water flows;
• Identify constraints and potential opportunities – quantitative, qualitative, erosion sensitivity, and environmental concerns related to storm water for both interim and ultimate development conditions;
• Identify existing storm water management requirements and/or criteria that apply specifically to the site (applicable watershed);
• Indicate the design assumptions and conceptual engineering schemes to manage both the quantity and quality of storm water run-off;
• Identify how the water balance requirement is to be achieved through the use of green infrastructure and/or
• Low Impact Development (LID) techniques;
• Assess mitigation measures to minimize any negative impacts on the storm water drainage system by applying appropriate on-site controls;
• Demonstrate that the storm water management proposal has maximized source control measures to reduce storm water runoff from the site and maximized conveyance control measures to infiltrate and/or treat storm water run-off as appropriate and consistent with water quantity and quality objectives;
• Indicate if off-site land or works are required to implement the storm water management proposal and comment to what extent (e.g. easements, dedication, land acquisition, etc.);
• Indicate the interim measures required for erosion, pond siltation and sedimentation, downstream works, and riparian flow considerations during the construction phase;
• Indicate if other agencies have jurisdiction and if their approvals or permits are required (e.g. MTO, MECP, Conservation Authority, Niagara Escarpment Commission etc.) and provide a record of approvals;
• Submit all storm water management plans, modeling results, and calculations to support the storm water management proposals.
• If a Drainage Proposal is requested, the outlet(s) is to be identified and storm sewer capacity verified.

The owner of the site is encouraged to discuss the need, scope, and proposed storm water management concepts and design assumptions with municipal staff prior to preparing the storm water management report.

All storm water management designs must meet the criteria set out by the Municipality, the MECP, and Conservation Authority. Storm water quantity control is typically implemented to minimize the potential for downstream flooding, stream bank erosion, and overflows of infrastructure. The objective of the water balance is to capture and manage annual rainfall on-site to preserve the pre-development hydrology. The water balance consists of runoff, infiltration, and evapotranspiration.
Detailed calculations and the design of the storm water management facilities and drainage systems based on the accepted principles in the draft report or Drainage Proposal, must be accepted prior to, or in conjunction with the final acceptance of the engineering drawings.

 For Additional Information please contact

• Miaoyi Xue, P.Eng
• Joo Min Park, MEng, P.Eng.
• Saloni Khoja, B.Arch.
• Edgar Labuac, P.Eng
• Rui Cong Xia, B.ASc(Civil)
• Weiming Lin, B.Eng
• Yuen Yu Ng, B.S.Sc
• Hoi Ching So, B.S.Sc
• Liu Sun, B.Des

LAND & BUILDING EXPERTS

Land Line: 416 332 1743

After Hours / Text Messages: 416 727 8336

Email: landbuildex@gmail.com 

Our well experienced, qualified professional engineers licensed in the Province of Ontario, specializing in Storm Drainage and Storm Water Management, prepare Storm Water Management Report to support Zoning By-law Applications, Plans of Subdivision and Condominium, Consent to Sever and Site Plan Control Applications and to obtain building permits in Ontario including City of Toronto, Durham Region, Halton Region, Peel Region, York Region, Hamilton (City of Hamilton), Oshawa (City of Oshawa), Pickering (City of Pickering), Clarington (Municipality of Clarington), Ajax (Town of Ajax), Whitby (Town of Whitby), Brock (Township of Brock), Scugog (Township of Scugog), Uxbridge (Township of Uxbridge), Burlington (City of Burlington), Halton Hills (Town of Halton Hills), Milton (Town of Milton), Oakville (Town of Oakville), Brampton (City of Brampton), Mississauga (City of Mississauga), Caledon (Town of Caledon), Vaughan (City of Vaughan), Aurora (Town of Aurora), East Gwillimbury (Town of East Gwillimbury), Georgina (Town of Georgina), Markham (City of Markham), Newmarket (Town of Newmarket), Richmond Hill (City of Richmond Hill), Whitchurch-Stouffville (Town of Whitchurch-Stouffville), Bradford West Gwillimbury (Town of Bradford-West Gwillimbury), King (Township of King) and Conservation Authorities including Toronto and Region Conservation Authority, Central Lake Ontario Conservation Authority, Credit Valley Conservation Authority, Conservation Halton, Lake Simcoe Region Conservation Authority, and Hamilton Conservation Authority.