1. Discharge in Descending Order
Table 2.8. Return period using Weibull Formula
Discharge (Cummecs)
Discharge in Descending Order
Rank
(m)
P = m/(n+1)
Probability
(%)
Return period
(1/p)
17713
30676 1
0.041
4.17
24.39
19914
23491 2
0.082
8.17
12.25
15548
23090 3
0.125
12.50
8.00
21272 4
0.180
17.96
5.56
20534 5
0.232
23.22
4.31
18225
20426 6
0.280
28.00
3.57
18885
19941 7
0.334
33.43
2.99
17012 8
0.383
38.25
2.61
19025
19389 9
0.441
44.14
2.26
16098 10
0.499
49.94
2.00
13792 11
0.553
55.32
1.81 12
0.624
62.42
1.60 13
0.695
69.47
1.44
17512 14
0.777
77.73
1.29
17139 15
0.827
82.69
1.21 16
0.888
88.83
1.12 17
0.934
93.40
1.07 18
0.962
96.20
1.61
11468 19
0.984
98.40
1.02 20
0.995
99.50
1.00
ONUIGBO I.C. et al. Flood Vulnerability Mapping of Lokoja Metropolis Using Geographical Information System
Techniques. Journal of Geosciences and Geomatics, 2017, Vol. 5, No. 5, doi: /jgg-5-5-2
© The Author(s) Published by Science and Education Publishing.