[b22smith]

Can I create my own custom unit hydrograph or do you have to create it? The City of Charleston, SC requires us to use the "ICPR 323" shape factor unit hydrograph. I think this is based on a Georgia DOT guideline. Data for the unit hydrograph is noted below that HydroCAD created for us based on the ICPR 323 unit hydrograph.

Unit Hydrograph Intensity vs. Time

Time ICPR 323
(Tp) (intensity)
-----------------
0.00 0.00000
0.10 0.02864
0.20 0.06873
0.30 0.12027
0.40 0.18328
0.50 0.25773
0.60 0.35510
0.70 0.45246
0.80 0.54410
0.90 0.56701
1.00 0.57274
1.10 0.56701
1.20 0.54983
1.30 0.51546
1.40 0.47537
1.50 0.43528
1.60 0.40092
1.70 0.36655
1.80 0.33792
1.90 0.30928
2.00 0.28637
2.10 0.26346
2.20 0.24055
2.30 0.22337
2.40 0.21191
2.50 0.19473
2.60 0.18328
2.70 0.17182
2.80 0.16037
2.90 0.15464
3.00 0.12600
3.10 0.11455
3.20 0.10309
3.30 0.09164
3.40 0.08018
3.50 0.07446
3.60 0.06300
3.70 0.05155
3.80 0.04009
3.90 0.02291
4.00 0.01718
4.10 0.01145
4.20 0.00573
4.30 0.00000
4.40 0.00000