2015. 9. 16
Hong-Tea Kim
Advance of Geomorpho-hydrological aspects
GIS technique
the rainfall-runoff simulation system that
developed using geomorpho-hydrological method lacks
⇒ Needs to be linked to the flood prediction and warning system of large river or build
up flash flood prediction model of mountain river and prediction and warning system
an automatic rain gauge and
waring device are installed and being operated, but enough grounds for warning
criteria for watersheds is no
GCUH
applied to sub-basin and mid-basin
characteristics of the rainfall-runoff
the ungauged
mountain basin
Trying to suggest a proper estimate method for the ungauged mountain basin
Develop K-GCUH formula through a topography similarity process of the Korea
mountain basin
By excluding the complicated GCUH parameters , a geomorph-hydrological unit
hydrograph can be estimated only using watershed area and river length data
Study area: Andong-Dam
The basin mean precipitation : using kriging method
Hydrological data(B1): data for actual unit hydrograph
Hydrological data(B2): long and short-term rainfall data for rainfall-runoff simulation
Building data for
watershed and hydrological data
Review for rainfall-runoff model in watershed
Building GIS and watershed data of study area
Hydrological data collection and arrangement
obs-1
Actual unit hydrograph
- hydrological data: B1, B2
Existing report, Matrix method
Review of unit hydrograph method
GCUH, Clark, Snyder, SCS method
case-1
case-2
Whether or not of flood routing method
- hydrological data: B1,B2
Channel: Muskingum-Cunge, reservoir: modified-Puls method
Case-2.1
Unit hydrological method: rainfall+Clark, linear GCUH, non-linear GCUH
Case-2.2
Flood routing: rainfall+ {Clark, linear GCUH,non-linear GCUH}+flood routing
Unit hydrological method, Flood routing method
case-3
Case-3.1
Runoff review by flood event types
- hydrological data: B2
Unit hydrological method: Clark, linear GCUH, non-linear GCUH
Case-3.2
Flood routing method: Clark, linear GCUH, non-linear GCUH
app-1
Fractal analysis and K-GCUH formula
app-2
Flash flood prediction and warning
system construction for mountain basin
Examples of applied GCUH theory
app-3
Topography and fractal analysis
for mountain basin
K-GCUH formula derivation
Design flood estimation and analysis
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K-GCUH
G2WMS
F2PUB
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Division
Flood
event
Period
Duration
day
Runoff
ratio
e1
89/07/22~08/08
18
0.72
1987~2003
e2
90/09/08~09/17
10
0.88
Gosun
1987~2003
e3
99/07/31~08/15
16
0.88
4
Yeongyang
1987~2003
e4
00/09/06~09/24
19
0.75
e5
02/08/30~08/16
18
0.75
Long-term multiplex rainfall
5
Andong
1983~2003
e6
02/08/30~09/04
6
0.85
Short-term single rainfall
6
Bonghwa
1988~2003
e7
03/09/11~09/16
6
0.79
Short-term double rainfall
7
Andong-Dam
1995~2003
8
Dosan
1984~2003
9
Socheon
1985~2003
No.
Station name
Data period
1
Poongsan
1987~2003
2
Euichon
3
Rainfall
Water-level
(Discharge)
< e1 >
< e2 >
< e3 >
< e5 >
< e6 >
< e7 >
Note
< e4 >
DEM & Rainfall·Water-level Station
Subbasin classify
Soilmap
Land-use
DEM
Subbasi
n
Soilmap
Landuse
Mimic
w1
R
1
w2
R
2
w3

Subbasin No.
Area
(km2)
River
Length
(km)
Ave.
slope
(m/m)
Altitude
Diff.
(m)
Lca
(km)
AMC-Ⅱ
w1
649.05
65.1
0.020
1304
w2
508.90
47.7
0.024
w3
423.59
51.1
0.014
Sum
1590.85
171.6
0.0085
CN
AMC-Ⅲ
Branching
ratio
(RB)
Extension
ratio
(RL)
Area
ratio
(RA)
Main ch.
length
(LΩ,km)
Main ch.
slope
(SΩ, m/m)
Area for
main ch.
(AΩ, km2)
Rough
-ness
(n)
Ave. width of
main ch.
(bΩ, m)
-
65
81
4.204
2.647
4.754
46.790
0.005
634.16
0.04
241
1157
-
64
80
3.501
2.073
3.942
20.670
0.003
511.16
0.03
205
726
-
65
81
3.373
1.932
3.731
22.229
0.002
430.29
0.025
180
1453
71.961
65
81
4.116
2.511
4.526
66.880
0.070
1590.85
0.027
481

Separation
Flood wave
Velocity ratio
(Vw/V)
Ave. width
(B, m)
Channel length
(L, m)
Channel slope
(S, m/m)
Roughness
(n)
Side gradient
(xH:1V)
R1
1.6
180
121642
0.001
0.04
0
1
R2
1.4
600
49946
0.0014
0.03
0
1
Cross section shape
1: rectangle
2: trapezoid
3: triangle

Basin
Area
(A, km2)
Length
(L, m)
Altitude Diff.
(H, m)
Ave. slope
(S, H/L)
Sogeumgang
24.871
8800
1114
0.127

TM coordinate
Longitude and latitude coordinate
Station name
X coordinate
Y coordinate
Longitude
Latitude
No. 1 rain gauge
344409.810
476710.240
128˚38´33˝
37˚46´40˝
No. 2 rain gauge
348594.470
475819.060
128˚42´14˝
37˚46´04˝

CN
River
Length
(km)
AMC-Ⅱ
8.8
85
AMC-Ⅲ
Branching
ratio
(RB)
Extension
ratio
(RL)
Area
ratio
(RA)
Main ch.
length
(LΩ,km)
Main ch.
slope
(SΩ, m/m)
Area for
main ch.
(AΩ, km2)
Rough
-ness
(n)
Ave. width of
main ch.
(bΩ, m)
93
4.487
2.091
3.201
3.164
0.112
24.871
0.078
24
Existing geomorphohydrological unit
hydrograph
Horton order interaction formula

𝑄𝑃 =
𝑄𝑃 =
Average width(bΩ) equation
1.101
𝑉
𝐿0.769
Ω
0.968𝐴0.138
Ω
𝐿Ω
𝑉
𝑡𝑃 =
0.47𝐿0.796
Ω
𝑉
𝑉𝐴0.0011
Ω
𝑡𝑃 =
0.535𝐿Ω
𝑉
𝑉𝐴0.122
Ω

K-GIUH, K-GCIUH, K-GCUH
(50KM2under,
50KM2
over)
𝑄𝑃 = 0.195
𝑄𝑃 = 0.145

𝑄𝑃 = 1.734
𝑡𝑃 = 0.921
𝑖𝑟1.4 𝐴0.575
𝑆Ω0.2 𝑡𝑟
Ω
𝑛𝐿0.785
Ω
𝑛𝐿0.871
Ω
0.5
0.4
𝑖𝑟 𝐴0.07
Ω 𝑆Ω
+0.75𝑡𝑟
1 − 0.121
0.2
𝑖𝑟0.4 𝐴0.07
Ω 𝑆Ω 𝑡𝑟
𝑛𝐿0.785
Ω
𝑄𝑃 = 1.538
𝑡𝑃 = 0.921
0.75
𝑖𝑟 𝐴0.38
Ω 𝑆Ω
𝑉
𝑛1.5 𝐿1.962
Ω
𝑖𝑟 𝐴0.702
𝑆Ω0.75
Ω
𝑛1.5 𝐿2.5
Ω
𝑉
𝑡𝑃 =3.519
𝑛1.5 𝐿2.5
Ω
𝑖𝑟 𝐴0.702
𝑆 0.75
Ω
𝑡𝑃 = 2.608
0.2
𝑖𝑟1.4 𝐴0.575
𝑆Ω0.2 𝑡𝑟
𝑖𝑟0.4 𝐴0.07
Ω
Ω 𝑆Ω 𝑡𝑟
1
−
0.121
𝑛𝐿0.872
𝑛𝐿0.872
Ω
Ω
𝑛𝐿0.871
Ω
0.5
0.4
𝑖𝑟 𝐴0.07
Ω 𝑆Ω
+0.75𝑡𝑟
𝑛1.5 𝐿1.962
Ω
0.75
𝑖𝑟 𝐴0.38
Ω 𝑆

w1
w2
Start
w1
w2
Simulation condition
J1
Topographical variables data entry
Rainfall data entry
Estimation of GCUH parameters
Estimation of effective discharge
R1
w3
하도
channel
w3
J2
Runoff hydrographs for watersheds
R2
channel
하도
w4





w4
J3
RS
저수지
reservoir
< G2WMS
RS
RS1
GCUH
K-GCUH
Clark
Snyder
SCS
mimic >
Base-flow estimation
Synthesis of runoff hydrograph and base-flow

category
Estimation method
Note
GCUH parameter and
Topographical variables
Using GIS program
w1, w2, w3, w4
Watershed runoff
K-GCUH, GCUH, Clark,
Snyder, SCS method
w1, w2, w3, w4
Channel
routing
Muskingum,
Muskingum-cunge
R1, R2
Reservoir
routing
Puls, Modified-Puls
RS1
Flood
routing
Input data for G2WMS simulation
Runoff hydrograph estimation in outlet
For i=1:niter
if SS=CR
Channel routing (Muskingum, Muskingum-Cunge)
Elseif SS=RR
Reservoir routing(Puls, modified-Puls)
Elseif SS=HM
Synthesis of runoff hydrograph
End
End
End
-
Result derivation
Save a file
< Snyder >
< Clark >
< GCUH >

< SCS >
Actual unit hydrograph
Non-dimension unit
Actual
representative unit
hydrograph
hydrograph
GCUH unit
hydrograph
Clark unit
hydrograph
Snyder unit
hydrograph
SCS unit
hydrograph
GCUH
Clark
Snyder
Timd of
concent
ration
(TP, hr)
Peak
discharge
(QP)
m3/sec
12.0
20.5
Timd of
concent
ration
(TP, hr)
Peak
discharge
(QP)
m3/sec
11.5
20.8
Timd of
concent
ration
(TP, hr)
Peak
discharge
(QP)
m3/sec
13.0
21.4
Timd of
concent
ration
(TP, hr)
Peak
discharge
(QP)
m3/sec
Timd of
concent
ration
(TP, hr)
Peak
discharge
(QP)
m3/sec
15.3
20.5
15.9
20.8
SCS
< Comparison of unit hydrographs >



< Strength and weakness of unit hydrographs >
Estimation methods
Assessment category
GCUH
Clark
Snyder
SCS
Ungauged mountain basin
applicability
good
good
common
common
GIS technique applicability
good
common
common
common
Optimization process
simple
complexity
common
common
Rainfall proportion
non-linear
linear
linear
linear
Estimation method of
input variables
complexity
simple
simple
simple
Hydrograph type
triangle
time-area curve
curve
SCS dimensionless curve
Considering of topographical
variables
lot
common
few
few
Adjustment parameter
-
Storage coefficient
Watershed characteristic
and storage coefficient
Lag time



Correlation : 0.81
Correlation : 0.69
Correlation : 0.76
Correlation : 0.76
< e1 >
< e2 >
< e3 >
< e4 >
Correlation : 0.79
Correlation : 0.79
Correlation : 0.78
< e5 >
< e6 >
< e7 >
Correlation : 0.85
Correlation : 0.77
Correlation : 0.85
Correlation : 0.86
< e1 >
< e2 >
< e3 >
< e4 >
Correlation : 0.96
Correlation : 0.83
Correlation : 0.82
< e5 >
< e6 >
< e7 >
Correlation : 0.66
Correlation : 0.89
Correlation : 0.76
Correlation : 0.71
< e1 >
< e2 >
< e3 >
< e4 >
Correlation : 0.40
Correlation : 0.73
Correlation : 0.68
< e5 >
< e6 >
< e7 >
Correlation : 0.68
Correlation : 0.88
Correlation : 0.81
Correlation : 0.41
< e1 >
< e2 >
< e3 >
< e4 >
Correlation : 0.62
Correlation : 0.76
Correlation : 0.66
< e5 >
< e6 >
< e7 >
Correlation : 0.68
Correlation : 0.42
Correlation : 0.69
Correlation : 0.84
< e1 >
< e2 >
< e3 >
< e4 >
Correlation : 0.86
Correlation : 0.55
Correlation : 0.67
< e5 >
< e6 >
< e7 >
Correlation : 0.90
Correlation : 0.88
Correlation : 0.94
Correlation : 0.91
< e1 >
< e2 >
< e3 >
< e4 >
Correlation : 0.90
Correlation : 0.88
Correlation : 0.89
< e5 >
< e6 >
< e7 >
< Input data of K-GCUH unit hydrograph for Estimation of Runoff in Watershed >
Mimic
w1
R1
R2
w2
w3
< G2WMS mimic of Andong-dam watershed>
Sub
-basin
River
Lengt
h
(km)
Main ch.
length
(LΩ,km)
Main ch.
slope
(SΩ, m/m)
Area for
main ch.
(AΩ, km2)
Rough
-ness
(n)
Ave. width of
main ch.
(bΩ, m)
CN
W1
65.1
46.79
0.005
634.16
0.04
241
85
W2
47.7
20.67
0.003
511.16
0.03
205
85
W3
51.1
22.229
0.002
430.29
0.025
180
85
< Input data of G2WMS model >
5
HC 1 0 0 0 0
KK H1
CR H1
Muskingum-Cunge 1.6 180 121642 0.001 0.04 0 1
KK C1
HM C1 NaN NaN NaN NaN 2 0 0 0 0
KK H12
CR H12
Muskingum-Cunge 1.4 600 49946 0.0014 0.03 0.1
KK C12
HM C12 NaN NaN NaN NaN 3 0 0 0 0
KK H123
ZZ
Collection of geomorphological and
hydrological data
Probability precipitation estimation for
duration-frequencies in rainfall point
Mean areal rainfall estimation
Time distribution of rainfall data
Initial and base-flow estimation
Base flood discharge estimation using rainfallrunoff model
Design flood discharge estimation
Critical duration decision
Design flood decision 결정
< Design flood estimation procedure >
< Compare of design flood discharge frequencies for Andong-dam watershed (48 hours) >
Classify
Location
Flood discharge frequency (m3/sec)
Area of
watershed
(km2)
50 yr.
80 yr.
100 yr.
200 yr.
Note
Nakdongriver flood
plan
(2004)
Before joining
Banbyeoncheon
1628
2350
2562
2713
3014
HECHMS
Result of
this study
Andong-dam
1591
2420
2752
2879
3379
G2WMS

Kriging System
Watershed division
Decision of duration
Duration : 10, 20, 30,…,120 min
Critical depth decision(Yb) of
outlet cross-section
0.5, 0.7, 1.0 m
Critical discharge(Qd) of outlet
cross-section
- Assuming a rectangular section
- Manning’s formula
Calculation of effective rainfall
using K-GCUH (QP= Qd)
𝑖𝑟 ∙ 𝑡𝑟 = 𝑅𝑒
𝑅𝑒 𝐴Ω
0.218𝑡𝑟
𝑄𝑑 = 2.42 0.4 1 −
Ⅱ𝑖
Ⅱ0.4
𝑖
CN calculation by
landuse and soilmap
Construction of Kriging
System
Grid weights calculation
for each point
Areal average rainfall
calculation of rainfall
data by durations
Thiessen Polygon method
Calculation of total rainfall(Rt)
by SCS method
𝑅𝑒 =
(𝑅𝑡 − 𝐼𝑎 )2
𝑅𝑡 − 𝐼𝑎 + 𝑆
Watershed division
Design of Thiessen
polygon
Thiessen rates calculation
for each point
Areal average rainfall
calculation of rainfall
data by durations
Decision of rainfall duration
Warning criteria system
Decision of warning criteria
Areal average rainfall(Ravg) > warning
criteria rainfall(Rt)
Warning

< Dangerous flow rate based on duration time at the Sogeum-stream watershed >
Time
(min)
Effective discharge
Reffective
(mm)
Critical rainfall
RT(mm), d=0.5m
Critical rainfall
RT(mm), d=0.7m
Critical rainfall
RT(mm), d=1.0m
Ia=0.2S
Ia=0.1S
Ia=0
Ia=0
Ia=0
10
2.47
12.17
10.22
8.27
8.74
9.26
20
3.07
13.32
11.37
9.42
9.97
10.58
30
3.52
14.12
12.17
10.22
10.82
11.51
40
3.89
14.76
12.81
10.87
11.52
12.26
50
4.22
15.32
13.37
11.42
12.12
12.91
60
4.53
15.82
13.87
11.92
12.66
13.50
70
4.81
16.28
14.33
12.39
13.16
14.05
80
5.09
16.72
14.77
12.82
13.64
14.58
90
5.36
17.14
15.19
13.24
14.10
15.08
100
5.62
17.54
15.59
13.64
14.54
15.58
110
5.88
17.94
15.99
14.04
14.98
16.06
120
6.14
18.33
16.38
14.43
15.41
16.55
Qd
(m3/sec)
17.07
19.40
22.22
Note
Warning
Evacuation warning 1
Evacuation warning 2
RT=(0.32XP1+0.68XP2)
< Warning criteria plan in Sogeum-stream basin (duration 20min) >
Watershed
division
Warning
warning
Sogeumstream
basin
reset
Existing plan
4mm/10mim
-RT : Total rainfall of duration 20 min
-P1 : Rainfall of duration 20 min in first rainfall gauge station
Improvement
plan
Content
Note
9mm/20mim
Duration 20 min, rainfall
causing water-depth of 0.5m
9.42
Evacuation
warning
1
6mm/10mim
10mm/20mim
Duration 20 min, rainfall
causing water-depth of 0.7m
Evacuation
warning
2
8mm/10mim
11mm/20mim
Duration 20 min, rainfall
10.58
causing water-depth of 1.0m
2mm/10mim
-
9.97
-P2 : Rainfall of duration 20 min in second rainfall gauge station
Total rainfall
estimation
<1st warning
station>
: warning
<2nd , 3rd
warning>
station:
warning
Warning
(RT>9mm)
Warning : 9mm/20min
Evacuation warning 1 : 10mm/20min
Evacuation warning 2 : 11mm/20min
< Flash flood warning criteria and warning procedure >





