Depending on the category of dam, flood hydrographs (and peak flows) are required for the 150-, 1,000- and 10,000-year events as well as the PMF. For each dam category, a different combination of design rainfall and rainfall-runoff models may be recommended. A subset of these is presented in Table 1.
Rainfall depth-duration-frequency model and rainfall-runoff model used for flood hydrology at UK dams (excerpt from Pether & Fraser (2019))
| . | 150-year return period . | 1,000-year return period . | 10,000-year return period . | PMF . |
|---|---|---|---|---|
| Rainfall depth-duration-frequency model | FEH2013 | FEH2013 | FEH2013 | FSR |
| Rainfall-runoff model | FSR/FEH and/or ReFH and/or ReFH2 | FSR/FEH and/or ReFH2 | FSR/FEH ReFH2a | FSR/FEH |
| . | 150-year return period . | 1,000-year return period . | 10,000-year return period . | PMF . |
|---|---|---|---|---|
| Rainfall depth-duration-frequency model | FEH2013 | FEH2013 | FEH2013 | FSR |
| Rainfall-runoff model | FSR/FEH and/or ReFH and/or ReFH2 | FSR/FEH and/or ReFH2 | FSR/FEH ReFH2a | FSR/FEH |
aReFH2.3, released in 2019, allows users to estimate the 10,000-year hydrograph.