Bedding is the process of preparing the area around a pipeline in order for proper installation to prevent maintenance problems. Critical velocity in storm water is the speed at which run off causes deformation or erosion to existing structures or channels. A drop inlet is a specific type of storm and wastewater drainage inlet that allows for reduction of velocity to avoid erosion to the manhole. Effluent is the discharged liquid waste or treated water from a treatment facility.
Erosion is the wearing away of material by physical and chemical forces.
For example, storm water can erode agricultural areas and erodes dry soil and even rock. The velocity of storm water runoff is the primary means by which particles are suspended in water and determines the amount of erosion on a site. Flows determine feed rates and treatment time. Grease from industrial and residential areas is prohibited from entering wastewater treatment facilities because it promotes the growth of the Nocardia, a filamentous type bacteria which is a major constituent of foam in activated sludge plants. Infiltration is any unwanted contamination source entering into water or sewer service lines or holding areas.