Construction: erosion and sediment control measures

Establish required perimeter controls, including erosion and sediment control (ESC) measures, prior to construction and adjust accordingly during construction. ESC measures come in two basic types: structural ESC, which slows and holds runoff from the disturbed area, dissipating erosive forces, promoting ponding, and allowing suspended particles to settle out; and non-structural ESC, which primarily minimizes the exposure time of stripped soils. STEP’s Erosion and Sediment Control Guide contains detailed guidance on the design, installation, inspection, maintenance, and decommissioning of ESC measures. For non-structual ESC measures, be sure to:

• Stage clearing and grubbing to minimize exposure of stripped soils.
• Watch the weather and adjust plans accordingly.
• Manage and demarcate heavy equipment routes away from LID practices.
• Use simple, common-sense methods, such as scarifying exposed soils perpendicular to the grade to prevent the development of rills.
• Create and use a pollution prevention plan for any fuels or solvents.

Generally, all exposed soils that are not being actively worked on must have temporary erosion protection or permanent cover within 7 days for slopes 3:1 or greater and 14 days for slopes 3:1 or lesser and 14 days for slopes 3:1 or flatter. This should apply to all exposed soil areas year-round and until the site is stabilized.

The table below gives practical advice on installing structural ESC measures for contractors, inspectors, and those who are new to construction and ESC practices.

Bioretention/Swales: Key Components, Descriptions and Routine I&M Requirements

Structural ESC measure	Do	Don't	(Pass) Photo Example	(Fail) Photo Example
Sediment fencing	Stake it in, support it, and double it up adjacent to natural heritage features.	Leave vulnerable areas with insufficient supports.	CDA has not changed in size or land cover. Sediment, trash or debris is not accumulating and point sources of contaminants are not visible.	This sediment fencing was not staked in at the likely point of failure, resulting in the release of sediment into an adjacent natural heritage feature. (Photo Source: North Carolina Cooperative Extension)

Soil, sand and minerals washed from land into water, usually after rain. They pile up in reservoirs, rivers and harbors, destroying fish-nesting areas and holes of water animals and cloud the water so that needed sunlight might not reach aquatic plans. Careless farming, mining and building activities will expose sediment materials, allowing them to be washed off the land after rainfalls.

The portion of water precipitated onto a catchment area, which then flows as surface discharge from the catchment area past a specified point.

Water from rain, snow melt, or irrigation that flows over the land surface.

Sustainable Technologies Evaluation Program

Soil, sand and minerals washed from land into water, usually after rain. They pile up in reservoirs, rivers and harbors, destroying fish-nesting areas and holes of water animals and cloud the water so that needed sunlight might not reach aquatic plans. Careless farming, mining and building activities will expose sediment materials, allowing them to be washed off the land after rainfalls.

Low Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting.

A shallow excavated surface depression containing prepared filter media, mulch, and planted with selected vegetation.

A shallow constructed channel, often grass-lined, which is used as an alternative to curb and channel, or as a pretreatment to other measures. Swales are generally characterized by a broad top width to depth ratio and gentle grades.