BASIC HYDROLOGY & INFILTRATION TEST

FACULTY OF CIVIL AND ENVIRONMENTAL

ENGINEERING

DEPARTMENT OF WATER & ENVIROMENTAL ENGINEERING

WATER ENGINEERING LABORATORY

LAB REPORT Subject Code BFC 21201

Code & Experiment Title MKA 01 ; BASIC HYDROLOGY AND INFILTRATION RATE TEST

Course Code 2 BFF/1

Date 31/10/2011

Section / Group 5/2

Name AFANDI BIN ABD WAHID (DF100122)

Members of Group 1.MUHAMMAD IKHWAN BIN ZAINUDDIN (DF100018)

2.MOHD HASIF BIN AZMAN (DF100079)

3.MUHAMMAD HUZAIR BIN ZULKIFLI (DF100040)

Lecturer/Instructor/Tutor CIK AMNANI BIN ABU BAKAR

EN JAMILULLAIL BIN AHMAD TAIB

Received Date 14 NOVEMBER 2011

Comment by examiner

Received

STUDENTS ETHICAL CODE

(SEC)

DEPARTMENT OF WATER & ENVIRONMENTAL

ENGINEERING

FACULTY OF CIVIL & ENVIRONMENTAL

ENGINEERING

UNIVERSITI TUN HUSSEIN ONN MALAYSIA

BATU PAHAT, JOHOR

I declare that I have prepared this report with my own efforts. I also

declare not receive or give any assistance in preparing this report and

make this affirmation in the belief that nothing is in, it is true

. (STUDENT SIGNATURE)

NAME : AFANDI BIN ABD WAHID

MATRIC NO. : DF100122

DATE : 14 NOVEMBER 2011


(SEC)


ENGINEERING


ENGINEERING


BATU PAHAT, JOHOR





NAME : MUHAMMAD IKHWAN BIN ZAINUDDIN




(SEC)


ENGINEERING


ENGINEERING


BATU PAHAT, JOHOR





NAME : MOHD HASIF BIN AZMAN




(SEC)


ENGINEERING


ENGINEERING


BATU PAHAT, JOHOR





NAME : MUHAMMAD HUZAIR BIN ZULKIFLI



PART A : BASIC HYDROLOGY

1.0 OBJECTIVE

To identify the relationship between rainfall and runoff.

2.0 LEARNING OUTCOME

At the end of the course, students should be able to apply the knowledge and skills they

have learned to :

Understand the basic terms in hydrology

Understand the concept of watershed area including time of concentration (tc) and

outlet or concentration point

Understand the factors which influence the runoff

3.0 INTRODUCTION

Hydrological cycle

The hydrological cycle describes the constant movement of water above, on, and

below the Earth's surface. The cycle operates across all scales, from the global to the

smallest stream catchment and involves the movement of water along evapotranspiration,

precipitation, surface runoff, subsurface flow and groundwater pathways. In essence,

water is evaporated from the land, oceans and vegetation to the atmosphere, using the

radiant energy from the Sun, and is recycled back in the form of rain or snow. When

moisture from the atmosphere falls to the Earth's surface it becomes subdivided into

different interconnected pathways.

Precipitation (excluding snow and hail) wets vegetation, directly enters surface

water bodies or begins to infiltrate into the ground to replenish soil moisture. Excess

water percolates to the zone of saturation, or groundwater, from where it moves

downward and laterally to sites of groundwater discharge. The rate of infiltration varies

with land use, soil characteristics and the duration and intensity of the rainfall event. If the

rate of precipitation exceeds the rate of infiltration this leads to overland flow. Water

reaching streams, both by surface runoff and groundwater discharge eventually moves to

the sea where it is again evaporated to perpetuate the hydrological cycle.

Rainfall characteristics

Precipitation in arid and semi-arid zones results largely from convective cloud

mechanisms producing storms typically of short duration, relatively high intensity and

limited areal extent. However, low intensity frontal-type rains are also experienced,

usually in the winter season. When most precipitation occurs during winter, as in Jordan

and in the Negev, relatively low-intensity rainfall may represent the greater part of annual

rainfall. Rainfall intensity is defined as the ratio of the total amount of rain (rainfall depth)

falling during a given period to the duration of the period It is expressed in depth units per

unit time, usually as mm per hour (mm/h).

The statistical characteristics of high-intensity, short-duration, convective rainfall

are essentially independent of locations within a region and are similar in many parts of

the world. Analysis of short-term rainfall data suggests that there is a reasonably stable

relationship governing the intensity characteristics of this type of rainfall. Studies carried

out in Saudi Arabia (Raikes and Partners 1971) suggest that, on average, around 50

percent of all rain occurs at intensities in excess of 20 mm/hour and 20-30 percent occurs

at intensities in excess of 40 mm/hour. This relationship appears to be independent of the

long-term average rainfall at a particular location.

The surface runoff process

When rain falls, the first drops of water are intercepted by the leaves and stems of

the vegetation. This is usually referred to as interception storage. As the rain continues,

water reaching the ground surface infiltrates into the soil until it reaches a stage where the

rate of rainfall (intensity) exceeds the infiltration capacity of the soil. Thereafter, surface

puddles, ditches, and other depressions are filled (depression storage), after which runoff

is generated. The infiltration capacity of the soil depends on its texture and structure, as

well as on the antecedent soil moisture content (previous rainfall or dry season). The

initial capacity (of a dry soil) is high but, as the storm continues, it decreases until it

reaches a steady value termed as final infiltration rate.

The process of runoff generation continues as long as the rainfall intensity exceeds

the actual infiltration capacity of the soil but it stops as soon as the rate of rainfall drops

below the actual rate of infiltration. The rainfall runoff process is well described in the

literature. Numerous papers on the subject have been published and many computer

simulation models have been developed. All these models, however, require detailed

knowledge of a number of factors and initial boundary conditions in a catchment area

which in most cases are not readily available. For a better understanding of the difficulties

of accurately predicting the amount of runoff resulting from a rainfall event, the major

factors which influence the rainfall-runoff process are described below.

4.0 THEORY

Runoff is generated by rainstorms and its occurrence and quantity are

dependent on the characeristics of the rainfall event, i.e. intensity, duration and

distribution. The rainfall-runoff process is extremely complex, making it difficult to

model accurately. There are, in addition, other important factors which influence

the runoff generating process like natural surface detention, soil infiltration

characteristics and the drainage pattern formed by natural flow paths. The soil type,

vegetative cover and topography play as important roles. Rainfall and runoff are very

important hydrologic components because of their direct relations with water

resources quantity, flood, streamflow and design of dam and hydraulic structure.

5.0 EQUIPMENTS

Figure 1: Basic Hydrological Instrument

Figure 2: Stopwatch

Figure 3: Rain Gauge

Inclination

adjustment Circulating

pump

Flow rate

measurement

Supply

tank

Measurement

weir

Switch

box

Plexiglass

cover

19-tube

manometer

Sprinkle

nozzle

Experiment tank

Filled with sand

6.0 PROCEDURE

Case 1: Flat and sandy soil surface profile (without slope)

Case 2: Flat and sandy soil surface with 1:100 slope profile.

i. The rail at side of the catchment area must be adjust to get the slope is zero, according

the requirement for Case 1.

ii. The steel ruler has been used to flat the sand or used our hand. That can be more easy

method.

iii. Set the time according the computer time.

iv. Put the rain gauge inside the rail and close the plastic curtains.

v. The pump has been switched on and starts the stop watch at the same time. The time

while start of rainfall has been recorded.

vi. The discharge and the reading from the rain gauge have been recorded every 30

second (during the rainfall).

vii. The pump has been switched off when the peak discharge achieved (after 3 discharge

reading with same value obtained) to stop the rainfall. The time while stop of rainfall

has been recorded.

viii. At the same time, record the discharge for each 30 second until 1020 second.

ix. The procedure has been repeated for case 2.

7.0 RESULT AND CALCULATION

Time, t

CASE 1 CASE 2

Water

Level

Discharge

Rain

gauge

reading

Water

Level

Discharge

Rain

gauge

reading

(s) (cm) (mm) (liter/min) (m3/s) (mm) (cm) (mm) (liter/min) (m

3/s) (mm)

30 1.5 15 2.5 41.7 x 10-6

0.6 0.7 7 0.3 5 x 10-6

29.8

60 2.7 27 9.5 158 x 10-6

3.6 1.5 15 2.5 41.7 x 10-6

32.4

90 2.9 29 12.5 208 x 10-6

6.2 2.8 28 11.5 192 x 10-6

35.2

120 2.9 29 12.5 208 x 10-6

8.8 2.8 28 11.5 192 x 10-6

38.0

150 2.9 29 12.5 208 x 10-6

11.4 2.8 28 11.5 192 x 10-6

40.6

180 2.9 29 12.5 208 x 10-6

14.0 2.8 28 11.5 192 x 10-6

43.6

210 1.8 18 4.3 71.7 x 10-6

0 2.6 26 8.5 142 x 10-6

0

240 1.1 11 0.9 15 x 10-6

0 1.7 17 3.4 56.7 x 10-6

0

270 0.8 8 0.5 8.3 x 10-6

0 1.5 15 2.5 41.7 x 10-6

0

300 0.7 7 0.3 5 x 10-6

0 1.0 10 0.8 13.3 x 10-6

0

330 0.7 7 0.3 5 x 10-6

0 0.9 9 0.7 11.7 x 10-6

0

360 0.6 6 0.2 3.33 x 10-6

0 0.7 7 0.3 5 x 10-6

0

390 0.5 5 0.1 1.67 x 10-6

0 0.7 7 0.3 5 x 10-6

0

420 0.5 5 0.1 1.67 x 10-6

0 0.7 7 0.3 5 x 10-6

0

450 0.5 5 0.1 1.67 x 10-6

0 0.6 6 0.2 3.33 x 10-6

0

480 0.5 5 0.1 1.67 x 10-6

0 0.5 5 0.1 1.67 x 10-6

0

510 0.5 5 0.1 1.67 x 10-6

0

540 0.5 5 0.1 1.67 x 10-6

0

570 0.5 5 0.1 1.67 x 10-6

0

600

TOTAL FLOW, BASEFLOW AND DIRECT FLOW

CASE 1 CASE 2 TIME, t Total flow, Q

m3/s

Base flow

m3/s

Direct flow m3/s

(Total flow Baseflow)

Total flow, Q

(x 10-6

)

Base flow (x

10-6

)

Direct flow m3/s

(Total flow Baseflow)

30 41.7 x 10-6

41.7 x 10-6

0 5 x 10-6

5 x 10-6

0

60 158 x 10-6

37 x 10-6

121 x 10-6

41.7 x 10-6

4.5 x 10-6

37.17 x 10-6

90 208 x 10-6

33 x 10-6

175 x 10-6

192 x 10-6

4 x 10-6

187.7 x 10-6

120 208 x 10-6

29 x 10-6

179 x 10-6

192 x 10-6

4 x 10-6

187.7 x 10-6

150 208 x 10-6

25 x 10-6

183 x 10-6

192 x 10-6

3.8 x 10-6

187.9 x 10-6

180 208 x 10-6

21 x 10-6

187 x 10-6

192 x 10-6

3.5 x 10-6

188.2 x 10-6

210 71.7 x 10-6

17 x 10-6

54.7 x 10-6

142 x 10-6

3 x 10-6

138.7 x 10-6

240 15 x 10-6

13 x 10-6

2 x 10-6

56.7 x 10-6

3 x 10-6

53.7 x 10-6

270 8.3 x 10-6

8.3 x 10-6

41.7 x 10-6

2.5 x 10-6

39.17 x 10-6

300 5 x 10-6

5 x 10-6

13.3 x 10-6

2.25 x 10-6

11.05 x 10-6

330 5 x 10-6

11.7 x 10-6

2.1 x 10-6

9.57 x 10-6

360 3.33 x 10-6

5 x 10-6

2 x 10-6

3 x 10-6

390 1.67 x 10-6

5 x 10-6

2 x 10-6

3 x 10-6

420 1.67 x 10-6

5 x 10-6

1.8 x 10-6

3.2 x 10-6

450 1.67 x 10-6

3.33 x 10-6

1.7 x 10-6

1.63 x 10-6

480 1.67 x 10-6

1.67 x 10-6

510 1.67 x 10-6

540 1.67 x 10-6

570 1.67 x 10-6

600

TOTAL 230 x 10-6

901.7 x 10-6

TOTAL 45.15 x 10-6

1051.69 x 10-6

Calculation

For Discharge

Calculation

For Case 1

Calculation

For Case 2

8.0 QUESTION

1. Plot the discharge (unit m3/s) versus time (second) graph separately from the

above values for each cases.

CASE 1 CASE 2 TIME, t DISCHARGE, Q

(s) (m3/s) (m

3/s)

30 41.7 x 10-6

5 x 10-6

60 158 x 10-6

41.7 x 10-6

90 208 x 10-6

192 x 10-6

120 208 x 10-6

192 x 10-6

150 208 x 10-6

192 x 10-6

180 208 x 10-6

192 x 10-6

210 71.7 x 10-6

142 x 10-6

240 15 x 10-6

56.7 x 10-6

270 8.3 x 10-6

41.7 x 10-6

300 5 x 10-6

13.3 x 10-6

330 5 x 10-6

11.7 x 10-6

360 3.33 x 10-6

5 x 10-6

390 1.67 x 10-6

5 x 10-6

420 1.67 x 10-6

5 x 10-6

450 1.67 x 10-6

3.33 x 10-6

480 1.67 x 10-6

1.67 x 10-6

510 1.67 x 10-6

540 1.67 x 10-6

570 1.67 x 10-6

600

2. From the graph plotted, determine:

a) Time concentration

Case 1 : 90 < tc < 180

Case 2 : 90 < tc < 180

b) Rainfall duration

Case 1 : 3.30 PM to 3.33 PM

So, rainfall duration are 180 seconds.

Case 2 : 4.00 PM to 4.03 PM

So, rainfall duration are 180 seconds.

c) Peak discharge

Case 1 : when 180 seconds, discharge will be 208 x 10-6

m3/s.

Case 2 : when 180 seconds, discharge will be 192 x 10-6

m3/s.

d) Runoff volume

Runoff volume = Total Direct Flow

Case 1 :

DF = 901.7 x 10-6

m3/s

= 901.7 x 10-6

m3/s x 3600s

= 3.246 m3

Case 2 :

DF = 1051.69 x 10-6

m3/s

= 1051.69 x 10-6

m3/s x 3600s

= 3.786 m3

f) Rainfall intensity

Case 1 :

Rainfall intensity = rain gauge maximum

rain duration

= 14 mm

180 s

= 0.0778 mm/s

Case 2 :

Rainfall intensity = rain gauge maximum

rain duration

= 43.6 mm

180s

= 0.242 mm/s

g) Storage volume

Storage volume = Base flow x 3600s

Case 1 :

storage volume = 230 x 10-6

m3/s x 3600s

= 0.828 m3

Case 2 :

storage volume = 45.15 x 10-6

m3/s x 3600s

= 0.163 m3

3. Provide a table for all the results obtained from (2) and make comparison with

case 1 and 2.

We conclude that, all of the deferent value in table between case 1 and case

2 because the slope. Case 1 without slope and case 2 with slope. We also observed

that the quantity of runoff decreased with increasing slope length.

Case 1 Case 2

Time concentration (s) 90 < tc < 180 90 < tc < 180

Rainfall duration (s) 180 s 180 s

Peak discharge (x10-6

m3/s) 208 191.7

Runoff volume (m3) 3.246 3.786

Rainfall intensity (mm/s) 0.0778 0.242

Storage volume (m3) 0.828 0.163

9.0 DISCUSSION

Runoff is generated by rainstorms and its occurrence and quantity are dependent

on the characteristics of the rainfall event, i.e. intensity, duration and distribution. There

are, in addition, other important factors which influence the runoff generating process.

The rainfall-runoff process is extremely complex, making it difficult to model accurately.

There are , in addition, other important factors which influence the runoff generating

process like natural surface detention, soil infiltration characteristics and the drainage

pattern formed by natural flow paths. Factors affecting runoff are:

Soil type

The infiltration capacity is among others dependent on the porosity of a soil which

determines the water storage capacity and affects the resistance of water to flow into

deeper layers. Porosity differs from one soil type to the other. The highest infiltration

capacities are observed in loose, sandy soils while heavy clay or loamy soils have

considerable smaller infiltration capacities. The infiltration capacity depends furthermore

on the moisture content prevailing in a soil at the onset of a rainstorm. The initial high

capacity decreases with time (provided the rain does not stop) until it reaches a constant

value as the soil profile becomes saturated.

Vegetation

The amount of rain lost to interception storage on the foliage depends on the kind

of vegetation and its growth stage. Values of interception are between 1 and 4 mm. A

cereal crop, for example, has a smaller storage capacity than a dense grass cover. More

significant is the effect the vegetation has on the infiltration capacity of the soil. A dense

vegetation cover shields the soil from the raindrop impact and reduces the crusting effect

as described earlier. In addition, the root system as well as organic matter in the soil

increase the soil porosity thus allowing more water to infiltrate. Vegetation also retards

the surface flow particularly on gentle slopes, giving the water more time to infiltrate and

to evaporate. In conclusion, an area densely covered with vegetation, yields less runoff

than bare ground.

Slope and catchment size

Investigations on experimental runoff plots have shown that steep slope plots yield

more runoff than those with gentle slopes. In addition, it was observed that the quantity of

runoff decreased with increasing slope length. This is mainly due to lower flow velocities

and subsequently a longer time of concentration (defined as the time needed for a drop of

water to reach the outlet of a catchment from the most remote location in the catchment).

This means that the water is exposed for a longer duration to infiltration and evaporation

before it reaches the measuring point. The same applies when catchment areas of different

sizes are compared. The runoff efficiency (volume of runoff per unit of area) increases

with the decreasing size of the catchment i.e. the larger the size of the catchment the

larger the time of concentration and the smaller the runoff efficiency.

Rainfall-runoff processes

Apart from recording and/or forecasting rainfall itself, the next most important

problem is understanding and forecasting the runoff generated by the rainfall. This

difficult problem has attracted enormous amounts of attention and effort around the

world. There are possibly as many models for calculating rainfall-runoff, as there are

people who have a direct interest in the subject. Runoff generation from rainfall over a

catchment can be assumed to depend on factors such as :

Atmospheric conditions over the catchment (wind speed, direction, temperature,

humidity)

The surface cover (type, distribution, interception, take up, evapotranspiration)

Surface soil (type, permeability, porosity)

Terrain (slope, surface texture)

Geology (structure distribution, permeability, porosity, groundwater levels)

Generally the following processes are usually identified as taking place:

Evapotranspiration at the surface

Surface infiltration

Overland flow

Unsaturated zone flow

Saturated zone flow (groundwater)

Rainfall and runoff are very important hydrologic components because of their

direct relations with water resources quantity, flood, streamflow and design of dam and

hydraulic structure. To convert discharge volume in liter/min to m3/s , we use this

formula.

Based on the graph discharge versus time in both case, we get the bell shape

graph. The value of discharge are increase when the time are increase. In case 1, the

storage volume are higest than the storage volume in case 2 but the value of runoff

volume in case 2 are higest than case 1.

Q, liter 1 m3

1 min

min 1000 liter 60 s

10.0 CONCLUSION

As conclusion of this experiment, we fully understand how to identify the

relationship between rainfall and runoff and it process. Besides that, we also can verify

that when the rainfall increased, the runoff will also increase until it reached the time of

maximum discharge. The slope area has the shorter time of concentration than the flat

area.

Runoff is one of the most important hydrology component because of it

connection with the water source quantity, flood, design of dam and others hydraulic

control structure. Using the rain gauge, we can record the discharge and its time for each

area which is slope or flat.

From this experiment, we can apply this knowledge to design the dam or drain.

The applications of the basic hydrology system were very important to control the flood.

Besides that, we can also use this application to avoid the high cost for construction the

dam or drain. Then, we also have determined all factors that effected runoff such as

rainfall intensity, type of surfaces, rainfall duration, and others.

PART B : INFILTRATION TEST

1.0 OBJECTIVE

To identify the characteristics of the infiltration rate of water into soils in the field.

2.0 INTRODUCTION

Some of the precipitation that falls on land seeps into the ground where it is stored

in aquifers and is transported to streams and lakes by subsurface flow. The amount of

infiltration is influenced by the permeability and moisture content of the soil, the presence

of vegetation and the volume and intensity of precipitation. The amount of water in an

aquifer is indicated by the height of the water table (the upper boundary of aquifer). This

animation illustrates the effect of soil permeability (large particles have large spaces

between them and let more water in) and precipitation volume (large rain events can lead

to more infiltration) on the amount of water stored in the aquifer.

3.0 THEORY

The volume of water used during each measured time interval is converted

into an incremental infiltration velocity for both the inner ring and annular space

using the following equations; VIR = VIR / (AIR .t) where, VIR is the inner ring

incremental infiltration velocity(cm/hr), VIR is the volume of water used during time

interval to maintain constant head in the inner ring (mL), AIR is the internal area of inner

ring (cm2) and t is the time interval (hour). For the annular space between rings,

calculate as follows; VA = VA / (AA .t) where, VA is the annular space incremental

infiltration velocity (cm/hr), VA is the volume of water used during time interval to

maintain constant head in the annular space between the rings (mL), AA is the area of

annular space (cm2) and t is the time interval (hour). The infiltration rate calculated with

the inner ring should be the value used for results if the rates for the inner ring and

annular space differ. The difference in rates is due to divergent flow.

4.0 EQUIPMENT

Two stainless steels rings measure 12 and 24 diameter x 20 high and some other

equipment

Wood block used to absorb the blow from the sludge hammer

Inner ring be inserted inside the large ring Depth of the ring was measured

5.0 PROCEDURE

i. Hammer the outer ring at least 2/5 height ring into the soil. Use the timber to protect the

ring from damage during hammering. Keep the side of the ring vertical.

ii. Hammer the inner ring into the soil or construct an earth bund around the 2/5 height ring

to the same height as the ring and place the hessian inside the infiltrometer to protect the

soil surface when pouring in the water. Make sure the ring in the centre outer ring.

iii. Start the test by pouring water into the outer ring until the depth is 10cm. Wait the water

down until the depth is 5cm. Then add the outer or large ring with water until the depth is

10cm again. At the same time, add water to the space between the two rings or the ring

and the bund to the same depth. Do this quickly.

iv. The water in the bund or within the two rings is to prevent a lateral spread of water from

the infiltrometer.

v. Record the clock time when the test begins and note the water level on the measuring rod.

vi. After 1-2 minutes, record the drop in water level in the inner ring on the measuring rod

and add water to bring the level back to approximately the original level at the start of the

test. Record the water level. Maintain the water level outside the ring similar to that

inside.

vii. Continue the test until the drop in water level is the same over the same time interval. Take

readings frequently (e.g. every 1-2 minutes) at the beginning of the test until 35munites.

6.0 RESULT AND CALCULATIONS

Time, t (s) Inner (mm) Infiltration Capacity

(mm)

Infiltration

(mm/s)

120 98 0.817 0.817

240 96 1.217 0.400

360 94 1.478 0.261

480 93 1.672 0.194

600 91 1.824 0.152

720 90 1.949 0.125

840 90 2.056 0.107

960 89 2.149 0.093

1080 88 2.231 0.082

1200 88 2.304 0.073

1320 87 2.370 0.066

1440 86 2.430 0.060

1560 85 2.484 0.054

1680 84 2.534 0.050

1800 83 2.580 0.046

1920 82 2.623 0.043

2040 80 2.662 0.039

2160 80 2.699 0.037

2280 79 2.734 0.035

2400 78 2.767 0.033

2520 77 2.798 0.031

2640 76 2.827 0.029

2760 76 2.855 0.028

2880 74 2.881 0.026

3000 73 2.905 0.024

3120 73 2.928 0.023

3240 73 2.951 0.023

Calculation For

Infiltration Capacity

And

Infiltration Rate

6.0 QUESTIONS

1. Plot a graph of:

a. Infiltration capacity versus time (Refer graph)

b. Infiltration rate versus time (Refer graph)

2. From graph in 1(b), please identify the basic of infiltration rate.

From the graph of infiltration rate versus time, the basic of infiltration rate for

this soil is wet soils.

3. Sketch a graph of infiltration rate versus time for three different characteristic of

soils:

i. Dry soil:

For the dry soil, we can see that the infiltration occurred faster than

other soil. This is because, water easier to absorb to the dry soil because inside

the soil, they have a lot of void.

ii. Wet soil:

For the wet soil, infiltration not too fast. It is slow than saturated soil.

This is because they already have a water inside the soil. So, the water was

slowly to absorb inside the soil.

iii. Saturated soil:

For the saturated soil, infiltration occurred very slow because they have a lot of water

inside the saturated soil that wet soil.

7.0 DISCUSSION

From the experiment, we can see that the types of soils influence the infiltration

rates. For dry soils, infiltration occurred faster, water can absorb faster than wet soil and

saturated soil because inside the soil, they have a lot of void. For wet soil, infiltration

occurred in modest time between dry soil and saturated soil because they already contain

water inside the soil. So, water slowly absorb into the soil. For saturated soil, infiltration

occurred very slowly because they have a lot of water inside the saturated soil that wet

soil. From the experiment, we consider that the soil are wet, after plot a graph of

infiltration rate versus time. The process of infiltration is not too fast because they already

have water inside the soil. So, the water was slowly to absorb inside the soil during the

experiment was carried out.

8.0 CONCLUSION

As conclusion of this experiment we found that the infiltration rate is affected by

the type of soil that we used. The infiltration rate is faster in a dry soil, become slowly in a

wet soil and very slowly in a saturated soil. Therefore, the infiltration capacity was

affected by the porosity of the soil and moisture content of the soil.

REFERENCES

Books

1. John F.D.2001.Fluid mechanics.fourth edition, pp 865-870. London: Prentice Hall

2. Munson, B. R. 2002. Fundamentals of Fluid Mechanics, pp 621-658. John Wiley

and Sons, Inc

3. Simon, A. L.1997. Hydraulics, pp 487-490. Prentice Hall, Inc

Internet

http://www.connectedwater.gov.au/processes/hydrological.html

BASIC HYDROLOGY & INFILTRATION TEST

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