A rainfall-runoff routing model was run for the 10% AEP design rainfalls with durations 1 hr, 2 hrs, 3 hrs, 4.5 hrs, 6 hrs, 9 hrs, 12 hrs, 18 hrs and 24 hrs, for a catchment located on the East Coast (North). Ten rainfall temporal patterns were considered in the model runs, as recommended by the AR&R2019. The ensemble results are shown below. Which peak flow should be taken as the 10% AEP flow? Pattern 1 .Pattern 4 Pattern 2 Pattern 5 Pattern 3 .Pattern 6 Pattern 7 Pattern 8 Pattern 9 Pattern 10 Average of 10 Patterns 880.0 780.0 680.0 580.0 480.0 380.0 280.0 180.0 Flow (m3/s) 960 1020 1080 1140 1200 1260 1320 1380 1440 Design Rainfall duration (min) 10% AEP Peak Flow (m/s) Duration Pattern Pattern Pattern Pattern Pattern Pattern Pattern Pattern Pattern (min) 1 3 Pattern 10 Average of 10 Patterns 60 294.0 255.0 335.7 269.1 259.4 263.3 279.5 270.9 245.5 247.8 272.0 120 315.0 270.0 410.4 294.0 324.0 317.6 320.2 313.4 300.0 305.3 317.0 180 332.3 326.1 437.7 357.2 390.5 389.3 349.5 360.3 367.4 393.9 370.4 270 445.2 398.7 526.4 478.6 523.2 521.6 468.3 482.8 492.2 527.8 486.5 360 536.3 443.7 602.7 584.4 586.6 588.3 564.9 596.3 565.5 576.0 564.5 540 600.0 528.0 662.4 688.8 660.0 645.6 688.8 810.3 836.7 623.3 674.4 720 697.3 631.8 822.0 752.4 827.7 782.4 702.7 815.7 620.3 676.2 732.9 1080 593.1 424.8 744.0 630.0 537.3 453.9 573.6 481.5 444.3 454.5 533.7 1440 540.0 316.2 567.0 326.4 645.0 630.0 519.6 470.7 441.0 435.0 489.1 245.5 m3/s 732.9 m3/s 836.7 m3/s 827.7 m3/s 272.0 m3/s