DEPARTMENT OF CIVIL ENGINEERING CENTER FOR DIPLOMA STUDIES WATER ENGINEERING LABORATORY
LABORATORY REPORT CODE AND EXPERIMENT COURSE / SUBJECT CODE
MKA – 01 01 (A) : BASIC HYDROLOGY
SECTION
01
MAKMAL KEJURUTERAAN ALAM SEKITAR DAN HIDRAULIK (DAC 31401)
EXPERIMENT DATE GROUP NAME GROUP MEMBERS
LECTURER / INSTRUCTOR / TUTOR NAME SUBMISSION DATE MARKS
RECEIVED STAMP
GROUP 8 MUHAMMAD ILHAM BIN ZULKIPLY SITI HAJAR BINTI ZAMRI SYARIFAH AISAR AZZIEMMIE IMTHISAL BINTI SAYED MOHD AZMI TENGKU DAENG DINIE AFIQ BIN TENGKU DAENG JOHAR ZUL ASYRAFF BIN ZULKEFLI
AA141130 AA141383 AA141370 AA140315 AA141173
ENCIK IZAT BIN YAHAYA 31 MARCH 2016 REPORT INTERVIEW OTHERS
35% 7.5% 7.5% 50% EXAMINER COMMENTS
1
STUDENT’S ETHICAL CODE (SEC)
DEPARTMENT OF WATER & ENVIRONMENTAL ENGINEERING CENTER OF DIPLOMA STUDY UNIVERSITY 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
: TENGKU DAENG DINIE AFIQ BIN TENGKU DEANG JOHAR
MATRIC NO : AA140315
DATE
: 31 MARCH 2016
2
STUDENT’S ETHICAL CODE (SEC)
DEPARTMENT OF WATER & ENVIRONMENTAL ENGINEERING CENTER OF DIPLOMA STUDY UNIVERSITY 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
: MUHAMMAD ILHAM BIN ZULKIPLLY
MATRIC NO : AA141130
DATE
: 31 MARCH 2016
3
STUDENT’S ETHICAL CODE (SEC)
DEPARTMENT OF WATER & ENVIRONMENTAL ENGINEERING CENTER OF DIPLOMA STUDY UNIVERSITY 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
: SITI HAJAR BINTI ZAMRI
MATRIC NO : AA141383
DATE
: 31 MARCH 2016
4
STUDENT’S ETHICAL CODE (SEC)
DEPARTMENT OF WATER & ENVIRONMENTAL ENGINEERING CENTER OF DIPLOMA STUDY UNIVERSITY 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
: SYARIFAH AISAR AZZIEMMIE IMTHISAL BINTI. SAYED MOHD AZMI
MATRIC NO : AA141370
DATE
: 31 MARCH 2016
5
STUDENT’S ETHICAL CODE (SEC)
DEPARTMENT OF WATER & ENVIRONMENTAL ENGINEERING CENTER OF DIPLOMA STUDY UNIVERSITY 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
: ZUL ASYRAFF BIN ZULKEFLI
MATRIC NO : AA141173
DATE
: 31 MARCH 2016
6
CONTENT ITEMS
1.0
PAGE 08
INTRODUCTION 10
2.0
OBJECTIVE
3.0
THEORY
4.0
APPARATUS
10 10 12
5.0
PROCEDURE 13
6.0
RESULT AND ANALYSIS
7.0
DISCUSSION
8.0
CONCLUSION
21 22 23
9.0
REFERENCE
7
1.0
INTRODUCTION
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.
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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, 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 for 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 highintensity, 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. 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. 9
2.0
OBJECTIVE
To identify the relationship between rainfall and runoff.
3.0
THEORY
Runoff is generated by rainstorms and its occurrence and quantity are dependent on the characteristics of the rainfall event such as intensity, duration and distribution. The rainfallrunoff 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 types of soil, the vegetative cover and topography play as important roles. Rainfall and runoff are very important hydrologic components because of their direct relation to water resources quantity, flood, streamflow and design of dam a nd hydraulic structure.
4.0
EQUIPMENT
Figure 1 : rain gauge
10
Figure 2 : stop watch
Figure 4 : supply tank
Figure 3 : switch box
figure 5 : measurement weir
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5.0
PROCEDURE
Case 1 : flat and sandy soil surface profile (without slope). Case 2 : flat and sandy soil surface with 1:100 slope profile.
1. The rail ate side of the catchment area was adjusted to get the slope zero. 2. The pump had been switched on and the stop watch also started. 3. The reading of the discharge and the rain gauge was recorded every 30 seconds. 4. The pump was switched off after three discharge reading with the same value was obtained (peak discharge) 5. The time while stop the rainfall has been recorded. 6. At the same time, the discharge for each 30 seconds until the reading reached 0.5 m³/s. 7. Step 1 to step 6 was repeated by the rail at the side of the catchment area was adjusted to 1.6mm.
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1.0
RESULT AND CALCULATION
Case 1 Time, t (s)
Water level (mm)
Discharge (liter/min)
Discharge (m³/s)
30 60 90 120 150 180 210 240 270 300 330 360 390 420 450 480 510 540 570 600 630 660 690 720 750 780 810 840 870 900
0 0 0 0 0 3 20 28 31 34 34 32 32 32 30 24 17 14 11 9 8 7 6 6 6 6 6 6 6 5
0 0 0 0 0 0 5.9 11.2 14.4 18.8 18.8 16.0 16.0 16.0 13.6 7.8 3.2 2.4 1.2 0.8 0.6 0.5 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.2
0 0 0 0 0 0 0.0000983 0.000187 0.000240 0.000313 0.000313 0.000267 0.000267 0.000267 0.000227 0.000130 0.0000533 0.0000400 0.0000200 0.0000133 0.0000100 0.00000833 0.00000667 0.00000667 0.00000667 0.00000667 0.00000667 0.00000667 0.00000667 0.00000333
Rain Gauge Reading (mm) 7 14 21 29 36 44 52 61 69 77 86 94 103 111 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Table 1 : shows the water level, the discharge and rain gauge reading
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TIME, t
30 60 90 120 150 180 210 240 270 300 330 360 390 420 450 480 510 540 570 600 630 660 690 720 750 780 810 840 870 900 Total
Total flow, Q (m³/s)
Case 1 Base flow (m³/s)
Direct flow (m³/s) (Total flow – Base flow) 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0.0000983 0.000002 0.0000963 0.000187 0.000004 0.000183 0.000240 0.000005 0.000235 0.000313 0.000007 0.000306 0.000313 0.000008 0.000305 0.000267 0.000010 0.000257 0.000267 0.000011 0.000256 0.000267 0.000013 0.000254 0.000227 0.000015 0.000212 0.000130 0.000016 0.000114 0.0000533 0.000018 0.0000353 0.0000400 0.000019 0.0000210 0.0000200 0.000020 0 0.0000133 0.0000133 0 0.0000100 0.0000100 0 0.00000833 0.00000833 0 0.00000667 0.00000667 0 0.00000667 0.00000667 0 0.00000667 0.00000667 0 0.00000667 0.00000667 0 0.00000667 0.00000667 0 0.00000667 0.00000667 0 0.00000667 0.00000667 0 0.00000333 0.00000333 0 = 0.000230 0.002746 Table 2 : shows the total flow, base flow and direct flow.
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Graph time(s) vs discharge(m³/s) Discharge 0.00035
0.0003
0.00025
0.0002
0.00015
0.0001
0.00005
0 30 60 90 120150180210240270300330360390420450480510540570600630660690720750780810840870900
Graph 1
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Case 2 Time, t (s)
Water level (mm)
Discharge (liter/min)
Discharge (m³/s)
30 60 90 120 150 180 210 240 270 300 330 360 390 420 450 480 510 540 570 600 630 660 690 720 750 780 810 840 870 900
0.3 2.5 3.2 3.3 3.3 3.3 2.8 2.0 1.6 1.4 1.1 1.0 0.9 0.8 0.8 0.8 0.8 0.8 0.7 0.7 0.7 0.7 0.7 0.6 0.6 0.6 0.6 0.6 0.6 0.6
0 9 15 17.5 17.5 17.5 11.5 5 2.9 2.0 1 0.9 0.8 0.5 0.5 0.5 0.5 0.5 0.3 0.3 0.3 0.3 0.3 0.2 0.2 0.2 0.2 0.2 0.2 0.2
0 0.00015 0.00025 0.00029 0.00029 0.00029 0.00019 0.000083 0.000048 0.000033 0.000017 0.000015 0.000013 0.0000083 0.0000083 0.0000083 0.0000083 0.0000083 0.000005 0.000005 0.000005 0.000005 0.000005 0.000003 0.000003 0.000003 0.000003 0.000003 0.000003 0.000003
Rain Gauge Reading (mm) 9 19 29 36 41 50 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Table 3 : shows the water level, the discharge and rain gauge reading
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Time, t
Total flow, Q (m³/s)
30 60 90 120 150 180 210 240 270 300 330 360 390 420 450 480 510 540 570 600 630 660 690 720 750 780 810 840 870 900 Total
0 0.00015 0.00025 0.00029 0.00029 0.00029 0.00019 0.000083 0.000048 0.000033 0.000017 0.000015 0.000013 0.0000083 0.0000083 0.0000083 0.0000083 0.0000083 0.000005 0.000005 0.000005 0.000005 0.000005 0.000003 0.000003 0.000003 0.000003 0.000003 0.000003 0.000003
Case 2 Base flow (m³/s) 0 0.000010 0.000023 0.000035 0.000045 0.000055 0.000067 0.000083
Direct flow (m³/s) (Total flow – Base flow) 0 0.00014 0.000227 0.000235 0.000245 0.000235 0.000123 0
= 0.000318 Table 4 : shows the total flow, base flow and direct flow.
0.00097
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Chart Title 0.00035
0.0003
0.00025
0.0002
0.00015
0.0001
0.00005
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 3 6 9 2 5 8 1 4 7 0 3 6 9 2 5 8 1 4 7 0 3 6 9 2 5 8 1 4 7 0 1 1 1 2 2 2 3 3 3 3 4 4 4 5 5 5 6 6 6 6 7 7 7 8 8 8 9
Time
Column1
Column2
Graph 2
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QUESTION
1. Plot the discharge (unit m³/s) versus time (second) graph separately from the above values for each case (case 1 to case 3). 2. From the graph plotted, determine: a) Time concentration, Case 1: 300 < tc < 330 Case 2: 120< tc < 180 b) Rainfall duration, Case 1: rainfall duration is 330 seconds. Case 2: rainfall duration is 180 seconds c) Peak discharge, Case 1: when 330 seconds, the discharge will be 3.13 x 10-4 m3/s Case 2: when 180 seconds discharge will be 0.00029 m3/s d) Runoff volume, Runoff volume = Total Direct Flow Case 1: DF = 0.002746 m3/s x 3600s =9.89m3 Case 2: DF= 0.00097 m3/s x 3600s = 3.492m3 e) Rainfall intensity, Case 1: Rainfall intensity = rain gauge maximum / rain duration = 86 mm / 330 s = 0.2606 mm/s Case 2: Rainfall intensity = rain gauge maximum / rain duration = 50 mm / 180 s = 0.28 mm/s
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f) Storage volume Storage volume = Base flow x 3600s Case 1: storage volume = 0.00023m3/s x 3600s = 0.828 m3 Case 2: storage volume = 0.000318m3/s x 3600s = 1.1 3. Provide a table for all the results obtained from (2) and make comparisons with case 2 and case 3.
Time concentration Rainfall duration Peak discharge Runoff volume Rainfall intensity Storage volume
Case 1 300 < tc < 330 330 s 3.13 x 10-4 m3/s.
Case 2 120< tc < 180 180 0.00029 3.492 0.2606 mm/s 0.28 0.828 m3 1.1448 Table 5 : comparison between case 1 and case 2
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7.0 DISCUSSION
From this experiment, we can see that rainstorms and its occurrence and quantity are dependent on the characteristics of the rainfall event, intensity, duration and distribution. We can conclude from this experiment that there are a few of the elements that contribute to the runoff generating process. We cannot make the right reading process. It caused by the parallax error from the rain gauge. It’s not perfectly stable. We need to wait for so long to take the reading from the rain gauge. As the result, our data are constant for a few minutes. The infiltration capacities depend on the porosity of a soil which determines the water storage capacity and affects the resistance of water to flow into a deeper layer. Higher infiltration capacity is always in the sand with porosity. W e
can see that the sand that’s been
used is perfectly functioning and the rain gauge is moving. Lastly, the water seems to be leaking from somewhere at the side of the catchment area. Its maybe will disturb the reading from the rain gauge. Our experiment is not a complete success.
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8.0 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. Using the rain gauge, we can record the discharge and it’s time for each catchment area. 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.
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9.0 REFERENCE
1. "Hydrologic Research Center". Hydrologic Research Center. Retrieved 8 March 2013. 2. http://www.scribd.com/doc/174047240/BASIC-HYDROLOGY-INFILTRATIONTEST#scribd 3. https://en.wikipedia.org/wiki/Hydrology
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