Erosion and sedimentation are naturally occurring processes involving the loosening, transport, and deposition of soils.

What is Erosion?

Erosion is the wearing away of soil materials, caused by the action of wind and water, through detachment and transport of materials from one location to another, usually at a lower elevation.

What is Sedimentation?

Sedimentation is the deposition of soil particles previously held in suspension by flowing water.

Stormwater runoff is part of the natural hydrological cycle, however, clearing, grading and other construction activities undertaken in the development of urban areas can result in accelerated rates of erosion and sedimentation.

If left uncontrolled this can result in irreparable harm, including degradation of surface water quality, loss of valuable topsoil, damage to adjacent land, harm to aquatic and vegetative habitat, and damage to water management and recreational infrastructure. The social, economic and environmental costs associated with these damages can be significant.

What is the City Doing to Address the Issue?

In November 2003, Drainage Services embarked on a project to develop Erosion and Sedimentation Control Guidelines  and an accompanying Erosion and Sedimentation Control Field Manual for development projects in the City.

The Guidelines and Field Manual were prepared to assist Drainage Services personnel, other City departments and staff, owners and developers, consultants, and contractors to understand Drainage Services' Erosion and Sedimentation Control (ESC) Framework and to meet the City's ESC requirements to achieve effective stewardship of environmental resources and continual improvement.

The Guidelines and Field Manual fulfil the following needs:

  • Provide a consolidated statement of Drainage Services' policies and expectations regarding ESC through all stages of a project
  • Clarify the respective roles and responsibilities for ESC of Drainage Services, owners and developers, consultants, and contractors and improve communications among all parties responsible for ESC
  • Identify applicable federal, provincial legislation, and municipal by-laws and standards, and encourage conformance with those laws
  • Assist parties in recognizing the causes of environmental damage and the various means of mitigating the risks, thereby reducing environmental impacts
  • Promote consistency and quality in the standard of efforts to protect the environment