Unlike a natural river, a storm drainage system can often have pipes of very steep slopes, sometimes more than 30%. The flows in such steep pipes are overwhelmingly very supercritical. A kinematical treatment is applied on such very steep pipes in which the Manning equation is used to replace the momentum equation during the solution process.

Related Topics:

• "Pressurized Flow"
• "Mixed (Transcritical) Flow"
• "Dry Bed (Low Flow)"
• "Flooding"