The major factors affecting culverts flowing under inlet control are:
- Entrance conditions including type, headwalls and wingwalls.
- Projection of the culvert into the headwater.
Following factors do not determine culvert capacity for culverts flowing under inlet control:
- Roughness of culvert.
- Length of culvert.
- Outlet conditions including depth of tailwater.
The figures below show three different types of culverts flowing under inlet control as shown in Figure 7.1 (Figure 27.6 (MSMA,2000) or Figure 18.2 (MSMA, 2011):
Figure 7.1: Figure 26.7 (MSMA.2000) or Figure 18.2 (MSMA,2011) Flow Profiles for Culvert Under Inlet Control
- Unsubmerged inlet of projecting end
2. Submerged inlet of projecting end
3. Submerged inlet of mitred end