PEAK FLOOD AND FLOOD HEIGHTS IN THE MARIKINA

RIVER CAUSED BY TS ONDOY

CP David, Ph.D. C. Abon, N. Pellejera, E. Pellejera, R. Rodolfo, L. Soria

Environment Monitoring Laboratory

UP National Institute of Geological Sciences

Total Area of Marikina Basin594.53 km2

PAGASA Science Garden Data*

Peak rainfall

10am 12nn 2pm

*the Marikina Watershed is 20km east of the Science Garden (~1-2hrs ahead)

Total Area of Modeled Sub-basins: 284.43 km2

Peak discharge: 2800 m3/s

Wawa Dam

J P R izal

0

2

4

6

8

10

12

0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30

T ime (h)

Flo

od

ht

(m)

1

2

3

4

5

6

7

Wawa

0

1

2

3

4

5

6

7

0 2 4 6 8 10 12 14 16 18 20 22 24

T ime (h)

Flo

od

ht

(m)

1

2

3

4

P ac ific B ridg e

01

2345

678

910

0 2 4 6 8 10 12 14 16 18 20 22 24

T im e (h)

Flo

od

ht

(m)

1

2

3

4

R odrig uez

0

1

2

3

4

5

6

0 2 4 6 8 10 12 14 16 18 20 22 24

T im e (h)

Flo

od

ht

(m)

1

2

3

4

5

6

S an Mateo B ridg e

0

2

4

6

8

10

12

0 2 4 6 8 10 12 14 16 18 20 22 24

T im e (h)

Flo

d h

t (m

)

1

2

3

4

5

6

7

B rg y. Nang ka

0

1

2

3

4

5

6

7

0 2 4 6 8 10 12 14 16 18 20 22 24

T im e (h)

Flo

od

ht

(m)

1

2

J P R izal

0

2

4

6

8

10

12

0 2 4 6 8 10 12 14 16 18 20 22 24

T im e (h)

Flo

od

ht

(m)

1

2

3

4

5

6

7

CONCLUSIONS/RECOMMENDATION

• Time lag between peak rainfall and peak flood = 2-9 hrs

• Focus on hazard preparedness

CONCLUSIONS/RECOMMENDATION

Anticipation of the timing and magnitude of a hazard

Gubat, Sorsogon

Batuan, Masbate09198415712

Caramoan, Cam Sur

CONCLUSIONS/RECOMMENDATION

Calculation of impending rainfall using public access data