THE GOVERNMENT OF THE THE DEPARTMENT OF PUBLIC WORKS AND HIGHWAYS Figure 2.1.5 The Study on Sabo and Flood Control for Western River Basins of in Sto. Tomas River Inundation Hazard Map the Republic of the Philippines (Probability 100 Years) JAPAN INTERNATIONAL COOPERATION AGENCY XIV-F9 ST Tomas River Inundation Analysis Result

Probable Damage Return Hazard House Road(km) Agriculture Period(years) Area(km2) (Number) National Others Total Field 2 39.85 3782 4.13 166.19 170.32 23.87 5 48.49 5045 4.91 218.63 223.55 28.62 10 53.95 5762 5.54 247.89 253.43 31.75 20 58.94 6444 6.02 273.75 279.77 34.65 30 62.20 6832 6.26 289.54 295.79 36.56 50 65.89 7296 6.91 307.53 314.44 38.68 100 71.04 8079 7.62 333.84 341.46 41.68

ST Tomas River

80.00 70.00 60.00 50.00 40.00 30.00 20.00 Hazard Area(km2) Hazard Area (km2) 10.00 Agriculture Field (km2) 0.00 0 20406080100 Return Period (years)

ST Tomas River

400.00 350.00 300.00 250.00 200.00 National 150.00 Others 100.00 Total

Length RoadHazard (km) 50.00 0.00 0 20406080100 Return Period (years)

ST Tomas River

9000 8000 7000 6000 5000 4000 3000 2000 House (Number)

HouseHazard (Number) 1000 0 0 20406080100 Return Period (years)

THE GOVERNMENT OF THE PHILIPPINES THE DEPARTMENT OF PUBLIC WORKS AND HIGHWAYS Figure 2.1.6 The Study on Sabo and Flood Control for Western River Basins of Mount Pinatubo in Result of Inundation Analysis (Sto. Tomas the Republic of the Philippines River) JAPAN INTERNATIONAL COOPERATION AGENCY XIV-F10 THE GOVERNMENT OF THE PHILIPPINES THE DEPARTMENT OF PUBLIC WORKS AND HIGHWAYS Figure 2.1.7 The Study on Sabo and Flood Control for Western River Basins of Mount Pinatubo in Land Use Condition from 1990 to 2001 the Republic of the Philippines JAPAN INTERNATIONAL COOPERATION AGENCY XIV-F11

Forest Area Unit:km2 1990 1992 1993 2001 Forest Area Iba 28.2 67.1 66.5 32.4 205.6 135.1 166.5 197.9 250.0 Cabangan 21.5 44.0 66.7 52.1 Iba 152.2 127.6 151.9 164.6 200.0 Botolan 35.2 30.6 Cabangan 150.0 San Felipe 2.9 10.5 22.2 29.3 San Marcelino

Km2 Castillejos San Narciso 0.9 4.2 8.6 9.8 100.0 San Antonio 0.4 11.8 23.7 24.6 San Felipe San Narciso Total 411.7 400.3 541.2 541.2 50.0 S an Antonio 0.0 1990 1992 1993 2001 Years

Cultivated area Unit:km2 Cultivated Area 1990 1992 1993 2001 Iba 28.1 3.4 16.8 58.0 120.0 Botolan 69.4 44.0 63.3 105.3 100.0 Iba Cabangan 32.5 24.2 22.6 33.3 Botolan San Marcelino 25.1 51.1 49.4 58.2 80.0 Ca banga n Castillejos 22.5 33.5 San Marcelino 60.0 Ca stillejo s San Felipe 19.0 16.2 24.4 32.8 Km2 San Narciso 28.8 16.5 31.2 34.2 40.0 San Felipe San Antonio 16.5 20.1 24.5 37.4 San Narciso 20.0 Total 219.5 175.6 254.7 392.6 San Antonio 0.0 1990 1992 1993 2001 Years

Grass+Bare land Unit:km2 Grass & BareLand Area 1990 1992 1993 2001 Iba 106.8 31.6 69.6 35.6 450.0 Botolan 413.8 161.6 208.9 175.3 400.0 Iba Cabangan 118.9 109.1 81.6 67.4 350.0 Botolan San Marcelino 179.8 135.6 102.7 58.2 300.0 Ca banga n Castillejos 33.9 22.6 250.0 San Marcelino Ca stillejo s San Felipe 97.9 93.6 67.3 38.3 Km2 200.0 San Narciso 44.3 59.2 28.4 15.9 150.0 San Felipe San Antonio 92.5 89.9 62.6 30.5 100.0 San Narciso Total 1054.1 680.7 655.2 443.8 50.0 San Antonio 0.0 1990 1992 1993 2001 Years

Lahar flow deposit Unit:km2 Lahar flow deposit Area 1990 1992 1993 2001 Iba 0.0 0.0 0.4 4.9 70.0 Botolan 6.9 56.5 53.2 60.2 60.0 Iba Cabangan 0.0 2.7 2.1 2.3 Botolan 50.0 San Marcelino 8.4 32.8 31.0 37.5 Ca banga n Castillejos 2.1 1.0 40.0 San Marcelino

San Felipe 0.4 8.9 4.1 4.8 Km2 30.0 Ca stillejo s San Felipe San Narciso 1.1 9.9 5.0 5.8 20.0 San Antonio 0.0 0.3 0.0 0.3 San Narciso Total 16.9 111.0 98.0 116.7 10.0 San Antonio 0.0 1990 1992 1993 2001 Years

Pyroclastic flow deposit Unit:km2 Pyroclastic flow deposit Area 1990 1992 1993 2001 Iba 0.0 0.0 0.0 0.4 250.0 Botolan 0.0 202.2 189.0 82.6 Iba 200.0 Cabangan 0.0 0.0 0.0 2.2 Botolan San Marcelino 0.0 34.6 18.8 12.8 Ca banga n 150.0 Castillejos 0.0 0.5 San Marcelino

San Felipe 0.0 0.0 0.0 0.9 Km2 Ca stillejo s 100.0 San Narciso 0.0 0.0 0.0 0.0 San Felipe San Narciso San Antonio 0.0 0.0 0.0 1.8 50.0 Total 0.0 236.8 207.9 101.3 San Antonio 0.0 1990 1992 1993 2001 Years

THE GOVERNMENT OF THE PHILIPPINES THE DEPARTMENT OF PUBLIC WORKS AND HIGHWAYS Figure 2.1.8 The Study on Sabo and Flood Control for Western River Basins of Mount Pinatubo in Trend of Land Use Condition from 1991 to the Republic of the Philippines 2002 JAPAN INTERNATIONAL COOPERATION AGENCY XIV-F12

Plain/Total Are a Farm La nd(ha) % of HH s S erve d Directly Farmla nd/po p Po p/Area(Number/ha) Ro ad(car) FarmLa nd/Total Are a FarmLan d/Total Are a

IRA/Area Po pulation(To tal year2 001) Build -up area/Total Are a Plain/Total Are a % of Schoo l childre n % of HHs Served Directly

Farmla nd/po p % of Schoo l childre n Farm L and(ha) Tota l Area(ha)

IR A / po p Mountain/Total Area

Road(car) Distance to Pob(min) P opulation(To tal year2 001) IR A / po p Tota l Area(ha) Po p/Are a(Number/ha) Distance to Pob(min) Build -up are a/Total Are a Mountain/Total Area IRA/Area

-0.5 -0.4 -0.3 -0.2 -0.1 0.0 0.1 0.2 0.3 0.4 0.5 -0.5 -0.4 -0. 3 -0.2 -0.1 0.0 0.1 0.2 0.3 0.4 0.5 the Principal Component 1 the Principal Component 2

Population(To tal year2 001 ) % of Schoo l childre n Road(car) IR A / po p % of HHs Served Directly Farmla nd/po p Po p/Area(Number/ha ) Farm La nd(ha)

Build -up area/Total Area Ro ad(car) Tota l Area(ha ) IRA/Area Farm L and(ha ) Build -up are a/Total Are a

IRA/Area Mountain/Total Area % of Scho ol ch ildren Distance to Pob(min)

Mou ntain/Total Area Po p/Are a(Number/ha)

Plain/Total Are a Tota l Area(ha) Farmla nd/p op Plain/Total Are a Distance to Pob(min) FarmLan d/Total Are a IRA/pop Po pulation(To tal year2 001) FarmLa nd/Total Are a % of HHs Served Directly

-0.4 -0.3 -0.2 -0.1 0.0 0.1 0.2 0. 3 0.4 0.5 0.6 0.7 -0.4 -0.3 -0.2 -0.1 0.0 0.1 0.2 0.3 0.4 0.5 0.6 the Principal Component 3 the Principal Component 4

% of Scho ol ch ildren IR A / po p Population(To tal year2 001 ) % of HHs Served Directly Mou ntain/Total Area Ro ad(car) Plain/Total Are a Mountain/Total Area

IRA/pop Po pulation(To tal year2 001)

Road(car) IRA/Area FarmLa nd/Total Are a Farmla nd/po p

% of HHs Served Directly Plain/Total Are a Po p/Area(Number/ha ) Build -up are a/Total Are a Distance to Pob(min) Tota l Area(ha)

Build -up area/Total Area Farm La nd(ha)

IRA/Area % of Schoo l childre n Farm L and(ha ) Distance to Pob(min) Farmla nd/p op FarmLan d/Total Are a Po p/Are a(Number/ha) Tota l Area(ha ) -0.6 -0.4 -0.2 0.0 0.2 0.4 0.6 0.8 -0.4 -0.2 0.0 0.2 0.4 0. 6 0.8 the Principal Component 5 the Principal Component 6

THE GOVERNMENT OF THE PHILIPPINES THE DEPARTMENT OF PUBLIC WORKS AND HIGHWAYS Figure 2.2.1 The Study on Sabo and Flood Control for Western River Basins of Mount Pinatubo in Vector of Each Principal Component (1/2) the Republic of the Philippines JAPAN INTERNATIONAL COOPERATION AGENCY XIV-F13

the Principal the Principal Component 1 Component 1 0.5 0.5 P lain/To Plain/To 0.4 0.4

0.3 0.3 Pop/Area % of HHs Fa rmL and Fa rmLand Pop/Area% of HH s IRA/Area IRA/Area Bu ild-up B uild-up 0.2 0.2

% of Sch Farmland Fa rm lan d % o f Sch 0.1 0.1 IRA/ pop Far m L an IRA/pop Farm Lan

0.0 Ro ad(car 0.0 Road(car

-0.1 Po pulati -0 .1 Populati

-0.2 -0 .2

-0.3 -0 .3 Distance Tota l Ar Distance To tal Ar -0.4 -0 .4 Moun tain Mo untain -0.5 -0 .5 -0.5 -0.4 -0.3 -0.2 -0.1 0.0 0.1 0.2 0.3 0. 4 0.5 -0.4 -0. 3 -0.2 -0.1 0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 the Principal Component 2 the Principal Component 3

the Principal the Principal Component 1 Component 1 0.5 0.5 Plain/To Plain/To 0.4 0.4 0.3 0.3 % of HHs FarmL and Pop/Area Pop/Area% FarmLaof HHs nd IRA/Area IRA/Area Build-up Build-up 0.2 0.2

Farmland % of Sch Farmland % of Sch 0.1 0.1 Farm Lan IRA/pop Fa rm Lan IRA/pop

Road(car 0.0 0.0 Road(car

-0.1 Popu lat i -0 .1 Po pulati

-0.2 -0 .2 -0.3 -0 .3 Total Ar Distance Total Ar Distance -0.4 -0 .4 Mou ntain Mou ntain

-0.5 -0 .5 -0.4 -0.3 -0.2 -0.1 0.0 0.1 0.2 0. 3 0.4 0.5 0.6 -0.6 -0. 4 -0.2 0.0 0.2 0.4 0.6 0.8 the Principal Component 4 the Principal Component 5

the Principal Component 1 0.5 Plain/To 0.4

0.3 Pop/AreaFarmLan d % of HHs IRA/Area Build-up 0.2

% of SchFarmland 0.1 Farm Lan IRA/pop

0.0 Road (car

-0.1 Populati

-0.2 -0.3

DistanceTot al A r -0.4 Mo unta in

-0.5 -0.4 -0.2 0.0 0.2 0.4 0.6 0. 8 the Principal Component 6

THE GOVERNMENT OF THE PHILIPPINES THE DEPARTMENT OF PUBLIC WORKS AND HIGHWAYS Figure 2.2.1 The Study on Sabo and Flood Control for Western River Basins of Mount Pinatubo in Vector of Each Principal Component (2/2) the Republic of the Philippines JAPAN INTERNATIONAL COOPERATION AGENCY XIV-F14