Development of Flood Hazard
Map at TTDI Jaya, Shah AlamBahazizi Ridzuan
Abd Jalil Hassan
East and SouthEast Asia Regional Seminar on Flood HazardMapping
7 – 9 Feb 2007

About NAHRIM• National Hydraulic Research Instituteof Malaysia (NAHRIM)• Under Ministry Of Natural Resources andEnvironment• Engaged in research and specialist

consultancy in all aspects of water
hydraulics and water environment.

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Content• Introduction• Objective• Methodology• Analysis & Finding• Conclusion• Future Improvement WorkStudy area
• Taman Tun Dr. Ismail Jaya (TTDI Jaya)• Total area – 265 acres (107 hectares)• Estimated Population – 12,000 peoples.
• Located at the confluence of Sg.
Damansara and Sg. Air Kuning• Upper catchment = 116km2

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Sg. Damansara Catchment

Study Area

3

TTDI Jaya
Study Area

Sg. Damansara

Flood history• Experienced 12 flood events since 1994
• Big flood– December 1995
– 6 December 1999
– 5 January 2000
– 26 February 2006 (The worst)

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Flood on 26th Feb 2006

Flood on 26th Feb 2006

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Flood on 26th Feb 2006

Flood damage (26th Feb 2006)• Estimate no of house flooded – 1842 units– Average damage / house = 15,000– Total damage = RM 27 Million• Estimate no of car submerged – 2800 units– Average damage = RM 5000/car– Total damage = RM 14 Million

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Objectives• To investigate the usefulness of FloodHazard Map (FHM) in Taman Tun Dr
Ismail Jaya (TTDI Jaya), Shah Alam• To develop a discrete simulation modelon traffic movement during flood• To solve traffic congestion at TTDI Jaya,Shah Alam during flood

Methodology• Data collection• Hydraulic Analysis and Simulation• Traffic simulation• Development of Flood Hazard Map7Data Collection• Site Visit• Survey• Interview TTDI Jaya communitycommittee• TTDI Jaya map and physical properties i.e.
road map, public facilities etc• Media information

Hydraulic Analysis and Simulation• Use InfoWorks RS• Inputs– rainfall– River cross section– Spill level– Flood plain Information• Focus on rate of water filling flood plain toidentify time required to evacuate8Hydraulic model

Traffic simulation model• Used Arena 10.0 by Rockwell Software Inc• Develop calibration model for 26th Feb 2006
– To test inputs assumption and comparing withavailable info obtained• Develop model on evacuation plan– To evaluate evacuation plan of TTDI Jaya community
committee by assuming all residents plan to savetheir cars

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Development of Flood Hazard Map• To educate and prepared residents inmanaging flood situation

Analysis from Survey
Prefered location to save car
30%

40%

Top priority item to save
14%

32%

52%

Not surebridge

Main road

16%

Other

Safe location in event of flood
Resident acceptance to Flood Hazard Map

NO -11%

16%
CarsSelfDocument

YES - 89%

Priority item to be save during flood
Acceptance of residents to ideaof Flood Hazard Map10FloodInundation
Map

Analysis and findings on Hydraulic
Simulation
Upstream of TTDI Jaya

Along TTDI Jaya

Comparison of observed andsimulated water level
Simulation Plot Produced by Abd Jalil (2/1/2007 10:50:21 AM) Page 1 of 1
Sim: >TTDI Jaya>Run Group>with pond 15min rain b>26Feb2006 15 min (1/30/2007 8:19:59 PM)
Selection List: >TTDI Jaya>Selection List Group>For calibration (1/29/2007 4:49:10 PM)

Discharge in Sg. Damansara atupstream and downstream of TTDI
Jaya

Flow...un Group>with pond 15min rain b>26Feb2006 15 minMin
19.560StageMax
280.305

Min4.743

Max
8.796

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Analysis and findings on HydraulicSimulation
Rise of water level (TTDI Jaya) - Simulated
1.4
1.2

Depth (m1
0.8
0.6
0.4

Flood warning system at
TTDI Jaya

0.2
03:36 AM

4:48 AM

6:00 AM

7:12 AM

8:24 AM

9:36 AM

10:48 AM

-0.2

Time (hrs)

Rise of water level in TTDI Jaya Simulated

Traffic Simulation Model• Calibration model inputs(26 Feb 2006)– No of cars whose owner
had intention to evacuate– Triangular distribution
represent vehicle exiting
behaviour from theirrespective residential area
– Estimate 2 seconds delay
at junction going out tosafe area
– Average speed of 20km/hr
used throughout
evacuationOQMPKIHNLJEFRGDCAB

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Traffic calibration model finding• It takes 28 minutes

for all residents withintention to move out
vehicles to three safearea – match withfeedback received

Calibration simulation

Traffic Simulation ModelN• Evaluation of3000

evacuation planinputs– 6 exits for different
areas. Either
mainroad or highland– All residents at homeand have intention ofevacuate vehicles– All vehicles go out atconcurrent time

300

600 Meters

FEW'W'DW'CW'AW'B

W'W'

Exit station

Exit direction
Inundation depth<1m>1m13

Traffic evacuation evaluation
findings
Number of Cars Exiting To Safe Place• At 30 minutes, only

3000
2500
T o ta l o f C a r

2399 cars able toevacuate, 652 cars
stranded

3500

2000

Maximum time to evacuate

1500
1000
500
05min

10min

15min

20min

25min

30min

35min40min

45min

Minutes
Total Number of Cars Exit From The System

Total Number of Cars Still On The System

Total Number of Cars

Evacuation Simulation

Traffic evacuation evaluation
findings• Cars stranded at exit

Numbers of cars exit at 30 minutes

900

869

Numbers cars caught in flood

800
N um ber of C a

C due to it take morethan 30 minutes forthem to evacuate• At Exit D and E is due
to capacity at safearea is not enough toaccommodate no. ofcars routed to thearea

1000

700

682

600
527

500

481

400
300
200
1471000A

140108633400B0CDEFExit Area

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Conclusion• Flood Hazard Map is required to increase awareness ofTTDI Jaya residents• FHP must have proper evacuation plan for vehicle
movement since it is a priority item
• On 26th Feb 2006, most residents does not heard thewarning siren and did not expect a big flood will occur• Total time from danger level to flooding of 0.3m depth is
1 hour. However, need precise flood forecasting system
to predict flood magnitude• “Flood drill”
drill” model need to be improve to ensure all carevacuate within 30 mins

Future Improvement Work• Develop DEM and combine with Hydraulic
Model to identify and improve floodinundation area
• Improve traffic model to provide better
evacuation plan15

Special thanks to• Undergraduate Trainee at NAHRIM– Amila Saliza Abd Wahab– Farhana Syed Ahmad• JPS Petaling• City Council of Shah Alam
• Community of TTDI Jaya

Thank You16