WasteWater Operator Certification - Grade 2 Practice Test

The approximate velocity in sanitary sewers is typically around 2 feet per second. This velocity is significant because it helps to ensure that wastewater is transported efficiently through the sewer system while minimizing the potential for sedimentation and the development of clogs. At this flow rate, the water can carry waste without becoming stagnant, which is crucial for maintaining a properly functioning sewer system.

A velocity of 2 feet per second strikes a balance; it is generally adequate to keep solids in suspension while also allowing for reasonable flow conditions. Lower velocities might lead to the settling of solids, creating blockages and requiring more maintenance, while higher velocities can increase the risk of scouring the pipe walls or causing wear and tear. Therefore, the target velocity of around 2 ft/s is optimal for effective transport of wastewater in sanitary sewer systems.