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Researchers:

 

The objectives of the study are: 

 

Abstract:

Urbanization, eliminating natural storages of the watershed and changing permeable surface to impermeable surface such as pavement and buildings roof, leads to rapid increment in peak flow and runoff volume during rainfall events. Consequently, flash floods happen in urban areas during a short duration rainfall.  Department of Irrigation and Drainage Malaysia (DID) has introduced in year 2000 the application of “on-source control” approach to solve current flood problems in urban areas in Malaysia.  Infiltration system is one of methods that have been proposed in Urban Stormwater Management Manual for Malaysia (MSMA) to control peak flows and runoff volume. 

The size of infiltration system and time for emptying the system are sensitive to infiltration coefficient (Zakaria et al., 2003). Hence, any uncertainty in the selection of infiltration coefficient value may lead to significant inaccuracy in the design of the system. However, infiltration coefficient is highly dependent on the in-situ soil condition. Factors influencing the infiltration rate include the condition of the soil surface and its vegetative cover, the properties of the soil (such as porosity and hydraulic conductivity), the current moisture content of the soil and the soil strata. 

Unfortunately, database on infiltration coefficients for local soil conditions have not been established yet. Without this database, designs have to be based on infiltration coefficient developed by others (such as USCS soil classification for USA) which may not be applicable for Malaysian soil at all. In fact, a comprehensive and systematic database of soil classification with respect to its infiltration capacity for major cities in Malaysia is essential not only for infiltration system designs but also for studying the applicable and effectiveness of infiltration system to control floods in both the technical and economical aspects. 

Based on the results of the infiltration tests that were carried out, infiltration maps were plotted for Butterworth and Universiti Sains Malaysia (USM) Engineering Campus, Nibong Tebal. The maps were plotted according to the infiltration capacity of soil type for each area (Fazly et al., 2005).

 

Selected Publications:


StudyArea thumbnail

Study Area (a) Butterworth (b) USM Engineering Campus

 

Hand Auger a thumbnail       Hand Auger b thumbnail

Soil Sampling Using Hand Auger

 

Double Ring Infiltrometer a thumbnail       Double Ring Infiltrometer b thumbnail

  Field Infiltration Test Using Double Ring Infiltrometer

 

Infiltration Curves a thumbnail       Infiltration Curves b thumbnail
(a) USM Engineering Campus   (b) Butterworth

Infiltration Curves

 

 Infiltration Test Result for Butterworth

Location fo (mm/hr) fc (mm/hr) Fc (mm2) k (hr -1) Horton Equation (mm/hr) fo/ fc
Kg. Lebai Tahir (Zon 1) 3250 1350 932.52 2.037  f = 1350 + 1900e-2.037 t 2.407
Kg. Sungai Lokan (Zon 5) 180 135 218.07 0.206  f = 135 + 45e-0.206 t 1.33
Kg. Maklom ( Zon 5) 1750 120 3791.1 0.430  f = 120 + 1630e-0.430 t 14.58
Kg.Jawa ( Zon 6 ) 460 96 604.14 0.603  f = 96 + 364e-0.603 t 4.79
Taman Limbungan (zon 1) 44 32 46.016 0.2608  f = 32 + 12e-0.2608t 1.375
Tmn Chantek (Zon 1) 247 25 292.85 0.7581  f = 25 + 222e-0.7581t 9.88
Tmn. Penisular (Zon 1) 640 120 742.61 0.7002  f = 120 + 520e-0.7002t 5.33

 

 

Infiltration Test Result for USM Engineering Campus

Location fo (mm/hr) fc (mm/hr) Fc (mm2) k (hr -1) Horton Equation (mm/hr) fo/ fc
O34 234.48 124.45 141.07 0.7799 f = 124.45 + 110e-0.7799t 1.88
Q17 50.70 16.11 22.07 1.5673 f = 16.11 + 34.59e-1.5673t 3.15
Q45 65.29 12.90 21.45 2.4427 f = 12.90 + 52.39e-2.4427t 5.06
S40 650.84 254.41 322.15 1.2306 f = 254.41 + 396.43e-1.23106t 2.56
T13 215.13 197.38 186.53 0.0952 f = 197.38 + 17.75e-0.0952t 1.09
U24 774.63 165.70 266.38 2.2859 f = 165.70 + 608.93e-2.2859t 4.67
U36 106.24 55.11 62.97 0.8120 f = 55.11 + 51.13e-0.8120t 1.93

 

Infiltration Map a thumbnail       Infiltration Map b thumbnail
(a) Butterworth   (b) USM Engineering Campus

Infiltration Map