Flow Pattern in the Port of Kalbut Situbondo

Shintya Rani, Engki A. Kisnarti and Rahyono

Hang Tuah University, Surabaya, Indonesia

Keywords: The Flow Pattern, Port of Kalbut Situbondo.

Abstract: One of the important reviews in port development is a current. The pattern and velocity of the current

greatly affect the movement of the ship, so this research is needed to know the pattern and speed of the

current at port of Kalbut Situbondo. The data used in this research are bathymetry, tidal, wind, and current.

Bathymetry, tidal, and wind data are processed using hydrodynamic modules. Based on the simulation

results the current pattern can be predicted that at high tide, the current flows from the Northeast to the

Southwest with a starting speed of 0.05 m/s up to 0.45 m/s. The current velocity at low tide is 0.05 m/s to

0.15 m/s which is flows from Southwest to Northeast.

1 INTRODUCTION

The Port of Kalbut Situbondo is a regional feeder

port whose main function is to serve the domestic

sea transport activities, the restructuring of domestic

sea transport in limited quantities, feeder for the

main port and gathering port, and as the place of

origin of passenger and goods destinations, and the

ferry transportation with service range within the

province. Site selection to build ports should take

into account the factors of the ocean and land

(Syaefudin, 2008). The flow review in the port

development plan is very important, as the current

determines how much sedimentation can occur at the

port.

The current is the movement of a mass of water

from one place to another caused by wind blowing

or caused by tidal movement of sea water (Nontji,

1993). The movement of water masses is caused by

three factors: wind, tidal currents, and turbulence

(Pond and Pickard, 1983). The currents can also be

formed by winds blowing in very long periods of

time, can also be caused by the waves that hit the

beach at an angle (Loupatty, 2013). It can also be

caused by waves formed from waves coming into

the shoreline, thus there will be two current systems

that dominate seawater movement i.e. rip current

and longshore current. The purpose of this research

is to know and analyze the direction and speed of

current in The Port of Kalbut Situbondo.

2 METHODS

This research was started from January to July 2017

and took place in Kalbut Harbor Waters located in

Semiring Village, Mangaran Subdistrict, Situbondo

District, East Java Province. Situbondo district is

adjacent to Madura Strait in the north, Border with

Bali Strait in the east, District of Bondowoso and

Banyuwangi in the south, District of Probolinggo in

the west (http://situbondokab.go.id). Geographically,

Kalbut Port is located at coordinates 07 ° 37'30 ° S

and 114 ° 01'00 ° E. The location of the study is

shown in Figure 1:

Figure 1: Research location at Port of Kalbut Situbondo.

Rani, S., Kisnarti, E. and Rahyono, .

Flow Pattern in the Port of Kalbut Situbondo.

DOI: 10.5220/0008373400380042

In Proceedings of the 6th International Seminar on Ocean and Coastal Engineering, Environmental and Natural Disaster Management (ISOCEEN 2018), pages 38-42

ISBN: 978-989-758-455-8

The materials required in this study are

bathymetry data obtained from the Pusat Hidro

Oseanografi TNI-AL (Pushidrosal), tidal data

obtained from field observations using tidal palms,

five years of wind data obtained from Badan

Meteorologi Klimatologi dan Geofisika (BMKG).

Current data obtained from field observations using

current meters at depth of 0.2d, 0.6d, 0.8d.

Equipment needed to assist data processing in order

to obtain the results of current patterns in the waters

of Kalbut Port Situbondo using hydrodynamic

module program.

The implementation of this research is divided

into two stages, the first stage is the data collection

bathimetri, tides, winds, waves, currents and

sediments and then proceed with data processing and

data analysis. The first step is to digitize the

bathymetry map to get the depth contour. Tidal data

is processed using Admiralty method to obtain tidal

harmonic constants (Fikri, et.al, 2013). Wind data as

a wave generator is used to determine the direction,

height, and significant period, while the current data

is processed to determine the current velocity as the

validation of the model results. The results of tidal,

bathymetric, and wind data processing as inputs to

create a simulation in hydrodynamic module

(Oktiarini, 2015) which will produce simulation in

the form of pattern and current velocity.

3 RESULTS

3.1 Bathymetry

The depth of Kalbut Waters Situbondo ranged from

2-5.2 meters indicated by the gradation of dark orange

to purple. The depth of the water in the pond is about

2-2.4, while slightly in front of the pond water depth

ranging from 2.8-4 meters. The average slope of the

topography of this area is 0.02 ° or 1:42. Based on

Verstappen which refers to the United State Soil

System Management (USSSM) and Universal Soil

Loss Equation (USLE), a slope of less than 1 ° is

included in the almost flat category (Verstappen,

1953). The bathymetry profile of The Port of Kalbut

waters region as shown in Figure 2.

Figure 2: Bathimetry of The Port of Kalbut Situbondo.

3.2 Tidal

The observed data obtained were calculated using

the admiralty method to find the tidal harmonic

constant. The harmonic constant will be used to

process time series data that will be input into the

hydrodynamic module. The harmonic constants are

as shown in Table 1:

Table 1: Constant tidal harmonics.

128 38 2 55 22

347 20 112 112

16 1 2 0.4 7

296 91 282 20 112

The values of the constants M2, S2, O1 and K1

have relatively larger values than the other constant

values because they are the major constants in the

tides used as determinants of the type of tides. M2 is

a constant influenced by the moon, O1 is a constant

influenced by the declaration of the moon, K1 is a

constant influenced by moon and sun declination,

whereas S1 is a constant influenced by the sun.

Among the four constants M2 and O1 values are

relatively larger than K1 and S2, this indicates that

the moon has a greater influence than the influence

of the sun in the up and down movement of water in

Kalbut Situbondo waters. Rthe tides are influenced

by the gravitational pull of celestial bodies,

especially the moon and the sun, because the

position of the moon closer to the earth, the gravity

of the earth is stronger so that its influence on tidal

fluctuations is also more Great than the sun

(Pariwono, 1989). The value of Fromzahl in these

waters is 0.97 which indicates that this type of tidal

Flow Pattern in the Port of Kalbut Situbondo

in these waters is a mixture of double daily skew

that occurs twice and twice a day at low tide but

occasionally occurs once and once the high tide has

high and time different.

The mean sea level (MSL) value of the waters is

128 cm from the zero point of the known tidal signs

of the constant value in Table 4.1 above in column

S0. After knowing harmonic constants, then can be

calculated face of low or low water and high water

that happened in those waters. The high water (HW)

that occurs in the area is 206 cm above the middle

seat or MSL, while the low water value (LW) in the

region is 49 cm below the middle seat or MSL. At

the time of tidal measurement there should be a

benchmark that serves as a bounding point of

measurement. The height of the benchmark for this

tidal measurement is 380 cm from the point of zero

tide sign. Tidal profile can be seen in Figure 3 and

Figure 4.

Figure 3: Benchmark profile of tidal signs.

Figure 4: Tidal fluctuation.

The tide is closely related to bathymetry, low

water or so-called Z0 is the zero point of the map in

the bathymetry map. Z0 serves as a zero in the

bathymetry, meaning that the entire depth of the

waters is measured from Z0 not from the bottom of

the waters. This is done for the sake of safety of

shipping. In the bathymetry field measurement

results are also required correction of the tides to be

able to know the actual depth before it is affected by

the tidal and low tide conditions. In the next stage,

this tidal data will be used as input in the program to

be able to know the current pattern and the

sedimentation that occurred. Tidal data will be

processed in the form of time series which is then

stored with a separate file form to later be used as

input material on the hydrodynamic module.

3.3 Wind and Wave

Wind data obtained made a form of wind rose to

determine the direction of wind movement, speed,

and frequency of wind movement. Wind that has

been processed into a form of wind rose indicates

that the first dominant wind direction comes from

the East with a frequency of 62%, the second

dominant wind comes from the North with a

frequency of 15%, the third dominant wind from the

North West with a frequency of 11%, and the fourth

dominant wind comes from the Northeast with a

frequency of 11%. The frequency distribution and

the result of wind roses can be seen in Figure 5.

Figure 5: Frequency of wind.

ISOCEEN 2018 - 6th International Seminar on Ocean and Coastal Engineering, Environmental and Natural Disaster Management

The dominant velocity of all dominant directions

is 1-1.5 m / s indicated by the red color then the

second dominant velocity is 0.5-1 m / s indicated by

the yellow color. These two dominant velocities are

highly visible in the first dominant wind direction

originating from the East. In the area of the water

visible speed 1-1.5 m / s is indicated by the red

frequency greater. The third dominant velocity of

1.5 - 2 m / s is indicated by the blue color. The

dominant speed is applicable in all dominant wind

directions. Based on the wind data can be

forecasting the wave to determine the significant

height (Hs) and significant period (Ts) of the wave.

The winds are sorted into significant winds corrected

to determine the wind above sea level (Uw) which

has a value of 5.25. Then from the value of Uw is

known value of wind voltage factor (UA) is 5.45. To

find out Hs and Ts have to know the fetch value as

presented in Table 4.2 and Figure 4.7 which yields a

fetch value of 98.2. Based on the value of UA and

fetch it can be known the value of Hs and Ts using

nomogram graph in Figure 2.6. Kalbut Waters Port

Situbondo has a Hs value of 0.7 m with a value of Ts

4.5 seconds.

3.4 Current

The pattern of current distribution in The Port of

Kalbut Situbondo when the tide flows from the

North to Northeast and Southwest with a speed of

0.02 - 0.28 m / s. The current velocity outside the

port gradually increases until the highest maximum

speed of 0.28 m / s reaches the front of the left jetty

mouth marked in red. There are two patterns of

distribution, some of the currents flowing from the

Northeast flow directly to the Southwest. The

second pattern is the current from the North, the

current flows towards the coast then the current

turns to two different directions ie to the Northeast

and Southwest. This is due to the current flowing

toward the coast obstructed by the rising coastal

topography so that the current is turned in two

different directions.

The current in the pond is relatively quiet with a

range of 0.02-0.04 m / s as it is protected by the

jetty. Current velocity at high tide is shown in Figure

6. At low tide (Figure 7) the current velocity in The

Port of Kalbut Situbondo ranges from 0.02-0.2 m / s

marked by blue to light green. The current pattern at

low tide flows from the Southwest to the Northeast,

increasingly to the Northeast increasing relative

speed which is characterized by the green color in

the Northeast. In the mouth of the jetty to the left

also occurs the addition of current velocity caused

by the jetty turns.

The difference in current velocity at both high

and low tides can be caused by different depths. The

current will be faster when the depth is increased, it

is also clearly indicated by the current at the next

tide on the right and left of the jetty. The current

velocity inside a very small port can be caused by

two things, the first being a jetty that deflects the

current coming from the North East so as not to

enter the harbor area, the second being the depth

towards the shallower shore, hampering the

movement of the current.

(a)

(b)

Figure 6: (a) Current pattern at high tide; (B) the current

pattern towards the pairs.

Flow Pattern in the Port of Kalbut Situbondo

(a)

(b)

Figure 7: (a) Current pattern at low tide; (b) the pattern of

the current toward receding.

The existence of two different patterns in tidal or

low tide conditions in a day due to the type of tidal

that occurs in this area of water is a mixture of

double daily skew. At a time when the currents

originating from the North usually occur at the turn

of the transit. At when the maximum tide, the

current flows from the Northeast with a long time

span, then becomes receded and the direction of

change in flow from the southwest, the decrease in

speed occurs briefly. At the time of re-currents

flowing from the North to the mainland and in the

two-way northeast of Northeast and Southwest, after

that become receded with the same direction of flow

until completely in real receding condition with the

current pattern flowing from the Southwest toward

Northeast with a long time.

4 CONCLUSIONS

There are two patterns of current in the waters of the

Port of Kalbut Situbondo that is the current flowing

from the Northeast to the Southwest at high tide and

at low tide flowing from the Southwest to the

Northeast. At the time of the transition when

heading to high tide or to the low tide, current flows

from the north to the beach and diverted to the

Northeast and Southwest. The mean current velocity

within the port area is 0.02-0.04 m / s.

REFERENCES

Fikri. I. A., 2013. Purwanto. Hariadi. Studi Pola Transpor

Sedimen di Perairan Pelabuhan Tanjung Adikarta

Pantai Gelagah, Yogyakarta. Jurnal Oseanografi. 2

No.2:171-178.

Loupatty, G., 2013. Karakteristik Energi Gelombang dan

Arus Perairan Di Provinsi Maluku. Jurnal Barekeng. 7

No.1: 19-22.

Nontji, 1993. A. Laut Nusantara. Djambatan.

Oktiarini. D., Atmojo. W., dan Widada, 2015. S. Transpor

sedimen di Lokasi Perencanaan Pembangunan

Pelabuhan Marunda, Jakarta Utara. Jurnal

Oseanografi. Vol.4 No. :325-332.

Pariwono, 1989. J. I. Gaya Penggerak Pasang Surut.

Dalam Pasang Surut. Ed. Ongkosongo, O.S.R. dan

Suyarso. P3O-LIPI. Jakarta. Hal. 13-23.

Pond, S dan G. L Pickard, 1983. Introducy Dynamical

Oceanography. 2nd Edition.

Syaefudin. 2008. Studi Pemilihan Lokasi Alternatif

Pelabuhan Trisakti Banjarmasin Propinsi Kalimantan

Selatan. Jurnal Hidrosfir Indonesia. ISSN: 1907-1043.

3 No.3:113-122.

Verstappen, H. Th, 1953. Applied Geomorphology,

Geomorphological Surveys for Environmental

Development, Elsivier, Amsterdam.

ISOCEEN 2018 - 6th International Seminar on Ocean and Coastal Engineering, Environmental and Natural Disaster Management