Hidrograma Unitario Sintetico SCS para crecidas

Hidrograma Unitario

1. HEC-HMS Surface Runoff Synthetic Unit Hydrographs – SCS Unit Hydrograph 1 Hydrologic Engineering Center

2. SCS The Soil Conservation Service (SCS) Unit Hydrograph is based on a dimensionless unit hydrograph Developed from average of UHs derived from gaged rainfall and runoff for a large number of small agricultural watersheds throughout the US Ordinates of dimensionless unit hydrograph are relative to peak flow, Q P, and time of rise, T R .

3. SCS UH – Illustrated Hydrologic Engineering Center 3 Source: NRCS (2007) 37.5% 62.5%

4. Welle & Woodward, 1989 Wanielista , et al. 1997

5. SCS UH – Equations Hydrologic Engineering Center 5 Peak discharge ( cfs ): where: A = drainage area (mi 2 )   : where: = rainfall duration ( hr ) L = watershed lag ( hr )     where: l= longest flowpath (ft) Y = average watershed slope (%) S = potential maximum retention (in) Mockus , 1961

6. SCS UH - Implementation in HEC-HMS Hydrologic Engineering Center 6

7. SCS UH – Adjusting Peak Rate Factor Hydrologic Engineering Center 7

8. SCS UH – Adjusting Lag Time Hydrologic Engineering Center 8

9. Thank you for listening! Visit our website! https://www.hec.usace.army.mil/confluence/hmsdocs/hmsum/4.7 https://www.hec.usace.army.mil/software/hec-hms/ 9