Expected performance benefits for various dewatering practices

Expected performance benefits for various dewatering practices.
Link to this table

	Dewatering Best Management Practices
	Sedimentation/ Settling Only (Sediment Traps/ Basins)	Filtration Only (Silt Fence, Dewatering Bag, Geotextile, etc.)	Pretreatment + Chemical Flocculants + Settling/Filtration **
Water quantity
Flow attenuation	Secondary benefit	Little or no benefit	Little or no benefit
Runoff volume reduction	Secondary benefit	Little or no benefit	Little or no benefit
Water quality
Soil erosion	Little or no benefit	Little or no benefit	Little or no benefit
Sediment control	Primary benefit	Primary benefit	Primary benefit
Nutrient loading	Secondary benefit	Secondary benefit	Secondary benefit
Pollutant removal
Total suspended solids	Primary benefit	Primary benefit	Primary benefit
Total phosphorus	Secondary benefit	Secondary benefit	Secondary benefit
Heavy metals	Secondary benefit	Secondary benefit	Secondary benefit
Floatables	Primary benefit*	Little or no benefit	Secondary benefit
Oil and grease	Primary benefit*	Little or no benefit	Secondary benefit

*If skimmer is used, otherwise secondary design benefit.

• • Benefits depend on the pH and temperature of the water being treated.