Calculate tailwater depth at culvert outlets with support for multiple channel types (rectangular, trapezoidal, triangular, natural). Analyze normal depth, critical depth, Froude number, flow regime, and outlet submergence. Optional rating curve generation.
| Channel Type | n |
|---|---|
| Concrete lined | 0.013 |
| Riprap lined | 0.035 |
| Grass lined | 0.030 |
| Natural - clean | 0.030 |
| Natural - weeds | 0.050 |
| Natural - brush | 0.070 |
| Floodplain - pasture | 0.035 |
| Floodplain - brush | 0.070 |
Source: Chow (1959), Table 5-6
| Control Type | Description |
|---|---|
| Normal Depth | Uniform flow in downstream channel |
| Critical Depth | Control section at or near outlet |
| Known WSE | Surveyed or calculated elevation |
| Downstream Pool | Pond, lake, or detention basin |
| Tidal | Coastal tidal influence |
Source: FHWA HDS-5, Chapter 4
Enter channel parameters and click Calculate to analyze tailwater conditions.
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