The Feasibility Study of the Flood Control Project for the Lower Cagayan River in the Republic of the Philippines
Final Report Supporting Report
Annex VI: Flood Control
Figures
Aparri
Lal-lo
Magapit
Tuao
Iguig
Solana
Enrile
Cabagan
Tumauini
Cauyan
Ilagan
Magat Dam
Mallig
Tuguegarao
EchagueSantiago
Jones
Nassiping
Bayombon
Alcala
Amulung
Magapit Br.
Buntun Br.
Tupang
Babuyan Channel
Pared River
Chico River
Tuguegarao River
Pinacanauan River
Tumauini River
Magat RiverIlagan River
Siffu River
Mall
ig R
iver
Addalam River
Mag
at R
iver
Cag
ayan
Riv
er
Cagayan River
Caraballo Mountains
Sierra Madre Mountains
Cordillera Mountains
Dummon River
0 10 20 30 40 50 kmScale
General Basin Map
N
The Feasibility Study of the Flood Control Projectfor the Lower Cagayan River
in the Republic of the Philippines
JAPAN INTERNATIONAL COOPERATION AGENCY
Figure 1.1.1
Dam
Diversion weir
River course
RoadBasin boundary
Sub-basin boundary
Legend
Sta Cruz River
VI-F1
The Feasibility Study of the Flood Control Projectfor the Lower Cagayan River
in the Republic of the Philippines
Figure 1.1.2
JAPAN INTERNATIONAL COOPERATION AGENCYSchematic River System of the Cagayan River
Babuyan Channel
Aparri
Alcala
Zinundungan River
Chico River Dummon River
Pared River
Tuguegarao River
Pinacanauan River
Tumauini RiverMallig River
Siffu River
Ilagan River
Ganano River
Addalam River
Cagayan River
Faire
Roxas
San Mateo Naguilian
Cauayan
Mallig
Santiago City
San Agustin
Total Catchment Area : 27,300 sq.kmRiver Length : 520 km
Note
Legend: City/municipality
: Rivers
Magapit
Nassiping
Tuguegarao City
Cabagan
Ilagan
Jones
Magat RiverSanta Cruz River
Source : Topographic Maps
VI-F2
Caba
gan
Tum
auin
i
Tugu
egar
aoBu
ntun
Br.
Par
ed R
.(R
)
Chi
co R
.(L)
Dum
mon
R.(
R)
Zin
undu
ngan
R.(
L)
Igui
g
Amul
ung
Alca
laN
assi
ping
Gat
tara
nM
agap
it Br
.La
l-lo
Apar
ri
Cag
ayan
R.
Mag
at R
.(L)
Ilaga
nT
ugue
gara
o R
.(R
)P
inac
anau
an R
.(R
)
Tum
auin
i R.(
R)
Sif
fu R
.(L)
Ilag
an R
.(R)
Gam
u Br
.N
agui
lian
Br.
Caua
yan
Gan
ano
R.(
L)
Add
alam
R.(
L)
Dal
ibub
on B
r.
Jone
s
1/10 1/100 1/200
1/500
1/10001/2000
0
500
1,000
1,500
2,000
0 100 200 300 400 500 600
Distance from River Mouth (km)
Elev
atio
n (E
L m
)Source:Topographic Map
VI-F4
River Width of the Cagayan River
0
1000
2000
3000
4000
5000
0 20 40 60 80 100 120 140 160 180
Distance from River Mouth (km)
Wid
th (m
)
Low Water Channel
River width including flood plain
Apa
rri
Mag
apit
Br.
Zinu
ndun
gan
R.(L
)
Dum
mon
R.(R
)
Chic
o R.
(L)
Nas
sipin
g
Pared
R.(R
)A
lcala
Bun
tun
Br.
Tugu
egar
ao R
.(R)
Sta.
Mari
a Br
.Pi
naca
naua
n R
.(R)
Cab
agan
-30
-20
-10
0
10
20
30
40
50
0 20 40 60 80 100 120 140 160 180
Ele
vati
on (E
l m
L e ft Bank
Right Bank
Deepest River BedMean River Bed
Riverbed Slope=1/21,000 Riverbed Slope=1/9,000Riverbed Slope=1/10,000 Riverbed Slope=1/7,000
Longitudinal Profile of the Cagayan River
Mean River Bed slope
VI-F5
Bankful Carrying Capacity
0
5000
10000
15000
20000
25000
0 20 40 60 80 100 120 140 160 180
Distance from River Mouth (km)
Car
ryin
g C
apac
ity (m
3 /s)
Apa
rri
Mag
apit
Br
Zin
undu
ngan
R.(
L
Dum
mon
R.(
R
Chi
co R
.(L
Nas
sipi
ng
Par
ed R
.(R
Alc
ala
Bun
tun
Br
Tug
uega
rao
R.(
R
Sta.
Mar
ia B
rP
inac
anau
an R
.(R
Cab
agan
-20
-10
0
10
20
30
40
50
Dep
th (m
)
Average River Bed
Deepest River Bed
Channel Depth below Riverbank Elevation
VI-F6
Bankful Carrying Capacity0
2000
4000
6000
8000
10000
12000
0 2 4 6 8 10 12 14
Distance from River Mouth (km)
Wid
th (m
)
The Feasibility Study of the Flood Control Projectfor the Lower Cagayan River
in the Republic of the PhilippinesFigure 1.1.6
JAPAN INTERNATIONAL COOPERATION AGENCYCharacteristics of Existinng River Channel
( Chico River)
VI-F7
Longitudinal Profile of the Chico River
-20
-10
0
10
20
30
40
Elev
atio
n (E
l m)
Left BankRight Bank
Deepest River Bed Average River Bed
Riverbed Slope=1/2,800
Channel Depth below Riverbank Elevation0
2
4
6
8
10
12
14
16
18
20
Average River Bed
Deepest River Bed
River Width of the ChicoRiver
0
200
400
600
800
1000
Law Water Channel
Bankful Carrying Capacity
0
2000
4000
6000
8000
10000
12000
14000
16000
0 2 4 6 8 10 12 14
Distance from River Mouth (km)
Wid
th (m
)
The Feasibility Study of the Flood Control Projectfor the Lower Cagayan River
in the Republic of the PhilippinesFigure 1.1.7
JAPAN INTERNATIONAL COOPERATION AGENCYCharacteristics of Existinng River Channel
(Tuguegarao River)
Longitudinal Profile of the Tuguegarao River
-10
0
10
20
30
40
50
60
70
80
Elev
atio
n (E
l m)
Left Bank
Right Bank
Deepest River Bed Average River Bed
Riverbed Slope=1/800
River Width of the Tuguegarao River
0
200
400
600
800
1000
1200
Law WaterChannel
Channel Depth below Riverbank Elevation
Average River Bed
Deepest River Bed
0
2
4
6
8
10
12
14
16
VI-F8
Geomorphological Survey Mapof the Cagayan River (1/3)
The Feasibility Study of the Flood Control Projectfor the Lower Cagayan River
in the Republic of the Philippines
JAPAN INTERNATIONAL COOPERATION AGENCY
Figure 1.1.8
N
VI-F9
The Feasibility Study of the Flood Control Projectfor the Lower Cagayan River
in the Republic of the Philippines
JAPAN INTERNATIONAL COOPERATION AGENCY
Geomorphological Survey Mapof the Cagayan River (2/3)
Figure 1.1.8
N
VI-F10
The Feasibility Study of the Flood Control Projectfor the Lower Cagayan River
in the Republic of the Philippines
JAPAN INTERNATIONAL COOPERATION AGENCY
Geomorphological Survey Mapof the Cagayan River (3/3)
Figure 1.1.8
N
VI-F11
The Feasibility Study of the F
lood Control P
rojectfor the L
ower C
agayan River
in the Republic of the P
hilippines
JAPA
N IN
TE
RN
AT
ION
AL
CO
OPE
RA
TIO
N A
GE
NC
Y
Figure 1.1.9
Typical cross-section of alluvial plain
FormerRiver Course Valley PlainExisting River
Mountain, Hill, Terrace Alluvial Plain
HigherAlluvial Plain
HigherAlluvial Plain
LowerAlluvial plain
LowerAlluvial Plain
LowerAlluvial Plain
Alluvial PlainWater Surface
Cliff Natural Levee Natural LeveePointBar
Back Swamp
Aparri
Lal-lo
Magapit
Babuyan Channel
0 1 2 3 4 5 kmScale
N
River Course Shifting (1/5)
The Feasibility Study of the Flood Control Projectfor the Lower Cagayan River
in the Republic of the PhilippinesJAPAN INTERNATIONAL COOPERATION AGENCY
Figure 1.1.10
Legend
Topographic map (1947 - 1953)
Aerial photographs (1979)
Aerial photographs (1996)
Aerial photographs (2000)
Road
A
C
DD
C
B
B
A
VI-F13
Gattaran
Nassiping
Alcala
Amulung
0 1 2 3 4 5 kmScale
N
River Course Shifting (2/5)
The Feasibility Study of the Flood Control Projectfor the Lower Cagayan River
in the Republic of the PhilippinesJAPAN INTERNATIONAL COOPERATION AGENCY
Figure 1.1.10
Legend
Topographic map (1947 - 1953)
Aerial photographs (1979)
Aerial photographs (1996)
Aerial photographs (2000)
Road
E
E
VI-F14
Solana
Tuguegarao
Iguig
Enrile
Namabbalan
0 1 2 3 4 5 kmScale
River Course Shifting (3/5)
N
The Feasibility Study of the Flood Control Projectfor the Lower Cagayan River
in the Republic of the PhilippinesJAPAN INTERNATIONAL COOPERATION AGENCY
Figure 1.1.10
Legend
Topographic map (1947 - 1953)
Aerial photographs (1979)
Aerial photographs (1996)
Aerial photographs (2000)
Road
F
FG
H
H
G
VI-F15
Cabagan
Tumauini
0 1 2 3 4 5 kmScale
N
River Course Shifting (4/5)
The Feasibility Study of the Flood Control Projectfor the Lower Cagayan River
in the Republic of the PhilippinesJAPAN INTERNATIONAL COOPERATION AGENCY
Figure 1.1.10
Legend
Topographic map (1947 - 1953)
Aerial photographs (1979)
Aerial photographs (1996)
Aerial photographs (2000)
Road
D
D
VI-F16
0 1 2 3 4 5 kmScale
N
River Course Shifting (5/5)
The Feasibility Study of the Flood Control Projectfor the Lower Cagayan River
in the Republic of the PhilippinesJAPAN INTERNATIONAL COOPERATION AGENCY
Figure 1.1.10
Legend
Topographic map (1947 - 1953)
Aerial photographs (1979)
Aerial photographs (1996)
Aerial photographs (2000)
Road
Legend
Topographic map (1947 - 1953)
Aerial photographs (1979)
Aerial photographs (1996)
Aerial photographs (2000)
Road
Ilagan
VI-F17
Variation of River Bed Elevation (Mean/Deepest)-30
-20
-10
0
10
20
30
40
Mean River Bed ('00)
Mean River Bed ('86)
Deepest River Bed ('86)
Deepest River Bed ('00)
-10
-5
0
5
10
15
20
0 20 40 60 80 100 120 140 160 180Distance from River Mouth
(km)
-2.4m ('00)
-2.6m ('86)
-1.7m ('00)
-2.1m ('86)
6.8m ('00)
6.6m ('86)
13.0m ('86)
13.0m ('00)
Variation of Average River Bed Elevation (Mean) for the Past 14 years
VI-F18
The Feasibility Study of the Flood Control Projectfor the Lower Cagayan River
in the Republic of the PhilippinesJAPAN INTERNATIONAL COOPERATION AGENCY
Figure 1.1.12
Cross-Sectional Variation (4/4)
VI-F22
Babuyan Channel
Aparri
Linao
Tallungan
Zanja
Bisagu
Paruddun Sur
Mbangug
Macanaya
The Feasibility Study of the Flood Control Projectfor the Lower Cagayan River
in the Republic of the PhilippinesJAPAN INTERNATIONAL COOPERATION AGENCY
Figure 1.1.13
Variation of Sandbar near River Mouth
Scale0 0.5 1 2 km
Legend
Topographic Map (1979)
Aerial photographs (1996)
Aerial photographs (2000)
VI-F23
The Feasibility Study of the Flood Control Projectfor the Lower Cagayan River
in the Republic of the Philippines
Figure 1.1.14
JAPAN INTERNATIONAL COOPERATION AGENCY
Flow direction
River bank consists of coarsesand with small stones
Track of natural levee/sand dune
Erosion
SedimentationSedimentation
Erosion
Erosion and Sedimentation Process due to River Meandering
2�`3H 2�`3H
H
Process of Erosion and Sedimentation at Bending Sections
Source: Yamamoto,1989: Chuuseki Kasenngaku, pp 183 and 184
Erosion and Sedimentation due to RiverMeandering
Erosion
Sedimentation
VI-F24
Nassiping
Alcala
Amulung
Solana
Tuguegarao
Iguig
Enrile
Meandering rate (S) Year AB CD S (km) (km) (AB/CD)1953 87.0 41.0 2.121979 78.0 41.0 1.901996 74.8 41.0 1.822000 74.4 41.0 1.81
Stra
ight
line
leng
th =
41.
0 km
Meandering rate
Meandering rate (S) = AB / CD
AB : Channel length CD : Straight line length
CA
Channel
DB
0 10 20 30 40 50 60
0 10 20 30 40 50 60
0.0
0.2
0.4
0.6
0.8
0.0
0.2
0.4
0.6
0.8
1950 1960 1970 1980 1990 2000 2010
Meandering rate (S)
( S=
AB
/CD
)
2.4
2.2
2.0
1.8
1.6
Meandering rate
Legend
Topographic map (1947 - 1953)
Aerial photographs (1979)
Aerial photographs (1996)
Aerial photographs (2000)
Road
The Feasibility Study of the Flood Control Projectfor the Lower Cagayan River
in the Republic of the PhilippinesJAPAN INTERNATIONAL COOPERATION AGENCY
Figure 1.1.15Meandering Rate in the Reach from Alcala to Tuguegarao
N
0 2 4 6 8 10 kmScale
VI-F25
The Feasibility Study of the Flood Control Projectfor the Lower Cagayan River
in the Republic of the Philippines
Figure 1.1.16
JAPAN INTERNATIONAL COOPERATION AGENCYRiver Meandering Characteristics (1)
VI-F26
(A) : Development Process of River Meander
: Pool (Deep) : Erosion
Data�@Source : Yamamoto, 1994 : The Kado Tokuseironn, Japan, Public Works Research Institute Paper Vol.2662, pp.80-109 and Kondrat'yev, N.Y
(B) : Relationship between Meandering Rate (S) and (B/Hmax) for Various Rivers
Data Source: Yamamoto, 1989 : Study note on influence on river channel characteristics by climatis, topography and soilconditions,Japan, Pulic Works Research Institute Paper Vol.2795, pp.88-124 and Schumm, S.A., 1960 : The shape of alluvialchannels in relation to sediment type,U.S. Geological Survey Professional Paper 352-B
0.0
0.5
1.0
1.5
2.0
2.5
3.0
1 10 100
B/Hmax
I= -1/1800I=1/ 800-1/1200I=1/1200-1/1600I=1/1600-1/2500I=1/2500-1/5000I=1/5000- 0
B: River width (m)Hmax.: Max. water depth (m)
Cagayan River
The Feasibility Study of the Flood Control Projectfor the Lower Cagayan River
in the Republic of the Philippines
Figure 1.1.17
JAPAN INTERNATIONAL COOPERATION AGENCY
(B): Relationship between Meandering Rate (S) and (B/R) for Various Rivers in India and Pakistan
River Meandering Characteristics (2)
Data Source: Yamamoto, 1989 : Study note on influence on river channel characteristics by climatis, topography and soil conditions,Japan, Pulic Works Research Institute Paper Vol.2795, pp.88-124
0.8
1.0
1.2
1.4
1.6
1.8
2.0
2.2
2.4
10 100 1000 10000B/R
d50(cm)0.004 - 0.010.01 - 0.020.021 - 0.050.051 - 0.10.11 - 0.48
d50=0.01-0.02
d50=0.02-0.05
Gravel
B: River width (m)R: Hydraulic mean depth (m)
Cagayan River
(A): Relationship between Meandering Rate (S) and (B/R) for Various Rivers in Indonesia
Data Source: Yamamoto, 1989 : Study note on influence on river channel characteristics by climatis, topography and soil conditions,Japan,Pulic Works Research Institute Paper Vol.2795, pp.88-124
B/R
0.0
0.5
1.0
1.5
2.0
2.5
1 10 100 1000
Ib=1/ 800-1/1200
Ib=1/1200-1/1600
Ib=1/1600-1/2500
Ib=1/2500-1/5000
Ib=1/9000
Ib=1/3000
Ib=1/2000
Ib=1/1000
CagayanRiver(Ib=1/9000)
B: River width (m)R: Hydraulic mean depth (m)
170
Present condition
after construction of cut-off channel
VI-F27
River Course in 1713 River Course in 1762
Present River Courseconfined by Dike
Present River Courseconfined by Dike
Old River Coursein 1713
Old River Coursein 1762
Japan Sea Japan Sea
Agano River Agano River
Floodway witha length of 4 km
Floodway witha length of 4 km
Diversion Channel Diversion Channel
NiigataCity
NiigataCity
0 3 km0 3 km
(Completed in 1730) (Completed in 1730)
NN
Data Source: Oya and Kato, 1984 : Agano River Geomorphologic Map
VI-F28
.
164416491660~16721672~1822?1823?1823?191319341953
River courses reproducedbased on old maps and
topographic maps
LegendHistorical River Course Shiftingin the Mogami RiverSakata CityMogami River
Japan Sea
Present River Course
Present River Course
River courses scattered in the past were finally confined to the presentone by continuous earth dike throughout historical river improvementworks
Sourse: Ohya, Kotouda, Wakamathu and Kubo,1982: River course shifting of the Mogami
MogamiRiver
0 1 2 3 km
VI-F29