Int. J. MAr. Sci. Eng., 4(1), 25-36, Winter & Spring 2014

ISSN 2251-6743

© IAU

Modeling of Hydrodynamic Factors for Management of Coastal

Hazards, Case Study: Khamir Port, Persian Gulf, Iran

1 * M. A. Nezammahalleh;

1M. Yamani;

1Sh. Soltani;

2A. Maldar Badeli;

3A. Rastegar

1 Geomorphology, Physical Geography Department, Geography Faculty, University of Tehran, Tehran, 2 Department of Civil Engineering, Neka Branch, Islamic Azad University, Neka, Iran

3 Department of Engineering and Technology, Golestan University, Aliabad Katool, Iran

Received 2 November 2013; revised 10 March 2014; accepted 26 April 2014

ABSTRACT: In coastal areas, hydrodynamic factors make changes in shorelines geomorphology. This can affect

coastal facilities and cause hazards to human societies in the areas. This study has investigated the influence of wave

and tide properties on Khamir Port, Hormoz Strait in coast of Persian Gulf. The purpose of the study is to make a

mathematical regional and local modeling of water level fluctuations and flow velocity by MIKE21 application.

These models provide some maps to show tide and wave effects on shoreline changes. The maps have been created as

the results to reveal the maximum advance of water onto the coast in high tide and low tide patterns. Time series of

water level variations in two months and the flow velocity have been examined in some randomly selected points in

the study area. This can be argued that these water level fluctuations may undermine coastal structures and alter

shoreline geomorphology. These maps resulted from the modeling can be used for safety planning in constructional

projects, tourism, and insurance management.

Keywords: hydrodynamic; coast; MIKE21; Khamir Port

INTRODUCTION

1 Coasts are the confluence of land and sea where many

varying factors including hydrodynamic and climatic

processes are effective on their arrangement and

morphogenesis (Fruergaard et al., 2013; Sherman,

2013). However, more considerable for determining

coastal hazards is the border of the land. This is

influenced by effects of marine processes upon the

shore, i.e., the interaction between land and sea, and

by advances of sea water onto the lands due to sea

level oscillations. Investigations on detection of

maximum advances of sea flows onto the land is the

most important management approaches and

measures against the marine floods and consequent

economic and social damages (Touili et al., 2014;

Peduzzi et al., 2012; Johnston et al., 2014;

Nezammahalleh et al., 2013). Indeed, the

investigation about the behavior of sea in shoreline

makes it possible to define a buffer zone for the

coasts both to obviate the influence of marine floods

and to avoid development of investments on the areas

(Sherman, 2013; Johnston et al., 2014). Hence, the

purpose of this research is to examine hydrodynamic

factors affecting coastal hazards (Tabeshpour et al.,

2013) and to recognize the coastal line by tide effects.

*Corresponding Author Email: mnezammahalleh@ut.ac.ir

This explains protection of a band along the coast

regarding natural phenomena and also environmental

and human requirements.

The northern coastal areas of Hormoz Strait are

affected by degradation due to erosion, transportation,

and deposition processes. The shoreline is changing

by the operation of different factors including the

processes due to hydrodynamics of water bodies and

also dynamics of land variables (Nezammahalleh et

al., 2013) as well as bio-climate situation and human

activities (Sherman, 2013; Todd et al., 2009). Khamir

Port on the northern coast of Hormoz Strait in Persian

Gulf has been separated as a county from the

administration of Bandar Abbas County under the

administrative division in 2004 and experienced

much development. Thus, it is necessary to determine

maximum advance of flows into the land and also to

know shoreline extents and the effective factors in the

area in order to conduct a coastal integrated

management and to mitigate the influence of marine

flooding.

MATERIALS AND METHODS

Hydrodynamic influence in coastal geomorphology:

Protection of coast against such processes as erosion,

sea level rise by storms, long term changes in sea

M. A. Nezammahalleh et al.

26

level and their breaking effects (Andersen, 2011) onto

coastal structures (Zendegani et al., 2012) involves

the study about the geomorphology of the coast

(Johnston et al., 2014). Thus, investigation on marine

phenomena in strip of shore including wave

propagation, tide characteristics, sea level changes,

and sediment behavior (Mojabi et al., 2013) are main

policies and suitable measures to reach the goals of

coastal protection.

Shoreline or the boundary of sea is directly defined

based on the influence of marine phenomena upon the

coast and the extent to which they impact the coastal

strip. It is essential to detect the areas of coast where

are influenced by the marine phenomena such as tidal

and long term fluctuations of sea level and the

advance of sea water onto the coast as a result of

wave setup, wind setup, and wave run up. This can be

as a coastal buffer zone with the steady and direct

interaction between sea and land (Fruergaard et al.,

2013).

Effective hydrodynamic parameters:

these factors are including tide, wave setup, wind

setup, and wave run up.

Tide: As during tide in open seas the water level

experiences continuous and almost regular changes,

the coastal areas accordingly varies as dry and wet

conditions through precession toward the land and

recession toward the sea (Robins et al., 2013). Given

the importance of the extent to which the flow

advance onto the land for land border determination,

the tidal characteristics must be considered as one of

the drastic factors for the definition.

To measure the quantitative values for the parameter

of tide in Khamir Port, MIKE21-HD-FM has been

used in this research (Sharifi et al., 2012). By this,

first a regional model after calibration determines the

properties of boundary conditions around a local

model. Then, the local model would be designed and

implemented based on hydrographic information,

with relatively fine mesh in the area of the project.

Wave setup: As a wave propagates toward coastal

area, it would be broken by the seabed at a point and

its energy would be dissipated (Hubard and Dodd,

2002; Vose et al., 2007). At the breaking point, the

average of sea level drops slightly due to an increase

in radiational tensions by depth decline. As the waves

propagate from the breaking point toward the coast,

the energy of the waves and the radiational tensions

are also decreased progressively. A continuous

increase, then, is occurred in the average of sea level

from the breaking point to the coast with the most at

the shoreline. The wave setup is the increase in

average sea level due to wave breaking and

propagation with a maximum rise at shoreline

(Hubard and Dodd, 2002; Vose et al., 2007;

Vousdoukas et al., 2009). The less the degree of slope

is the more advance the water would have onto the

coast and the wider the area it would impact and vice

versa.

In order to get quantitative values of the parameter in

the area, the annual properties and wave design have

first been determined for water near the area of the

project and then propagation of the designed wave

towards the coastal areas has given the wave setup of

the designed waves. In the method after the available

statistics of wind and wave of the area have been

explored, the statistics for basic studies will be

selected and the generation and propagation of waves

onto the coasts of the project area have been modeled.

The wave transfer modeling is conducted in two

stages: in the first stage, the process of wave

propagation and generation of effective parameters on

the waves are modeled using MIKE 21 SW from

deep waters to the area near project (Moeini and

Etemad-Shahidi, 2007; Sharifi et al., 2012). With the

calculation of wave rose, the designed waves have

been determined in varying effective directions for

different return periods using MIKE EVA. In second

stage based on exact local hydrographic information,

the modeling of designed wave transfer and wave

propagation towards the coast and shallow waters has

been carried out using LITPACK/LITDRIFT Model

and the characteristics of wave setup due to the

propagation have been calculated to recognize its

impact upon the bed and the buffer zone.

Wind setup: As winds blow over the seas, tensions

due to the friction between surface of water and air

flow give rise to a change in the water surface relative

to a normal condition so that it makes an oblique

plane in the surface of water with a low angle (Todd

et al., 2009). The increase in water level by wind as

that of wave setup causes the advance of water onto

the coastal lands depending on the slope of the

offshore areas.

In order to have the quantitative values of the

parameter, MIKE21-HD-FM has been used for the

area. The 2 dimensional horizontal equations of

shallow water flows are used in the Software as the

average flow equations in depth. After the effects of

wind on the water surface, including fluctuations and

flows, has been simulated, analysis of limit values has

then been applied to estimate the design values of

wind setup. Indeed, using EVA Tool in MIKE-ZERO

based on recommended distributions and maximum

method, the amounts of increase in water levels have

been calculated for return periods of 1, 2, 5, 10, 25,

50, and 100 years.

Wave run up: As a wave breaks, the remaining energy

forces the water to run up the coast and coastal

structures. The general trend of the phenomena

indicates that the amount of such run up over the

Int. J. Mar. Sci. Eng., 4(1), 25-36, Winter & Spring, 2014

27

structures is the maximum vertical height of water

level. A prediction of wave run up can be applied to

determine the crest of a coastal structure and also to

specify the buffer of prohibition for the structures.

Since in the area of this project the coast has low

slope and the value of the parameter must be low, we

have not calculated the parameter (Hubard and Dodd,

2002; Vose et al., 2007; Vousdoukas et al., 2009).

Shoreline determination by tide:

Given the importance of the extent to which the water

advance onto the coast in specifying the boundary of

land in shore strip, the tide characteristics as an

effective factor must be taken into account for

identification of the boundary. In this section, the

pattern of water level fluctuation and the flows due to

tide must be examined in the area. The results of the

studies including velocity of the flumes and sea level

changes can be used in identification of shoreline and

of design sea level as well as the design of coastal

structures. The primary tool to obtain such a pattern is

mathematic modeling of hydrodynamics. This tool

makes it possible to determine the pattern of velocity

changes in flows and water level due to tide in the

area of the project.

After identification of the changes of water level by

tide in the study area (by the data from National

Cartographic Center of Iran), the model for Persian

Gulf as global model has been designed and

implemented. It has been also calibrated based on the

predicted levels in the proximity of the study area.

Then, the local model of hydrodynamics has been

designed based on the hydrographic information

available of the area. The boundary condition of

information of local model has been implemented

using the output results of regional model and the

output results are presented as changed in water level

and velocity by tide effects.

Mathematic modeling of water level fluctuations and

flow velocity by tide:

Given that for the implementation of a model of tidal

flow in the area there are not enough data, the

information about the needed boundary conditions

have been obtained from running a mathematic model

in a wider region. As a next step, a more limited

model has been used in the vicinity of the area with a

suitable resolution to compute the properties of tidal

waves. The wider model is the regional model and the

limited is the local one.

Regional model:

In the designed regional model on the area of this

research including entire the Persian Gulf and some

area of Oman Sea the water level data in tide gauges

in Chabahar Port in eastern coasts of Iran have been

used as boundary condition (f1). The output results of

regional model can be exploited as information of

boundary condition that is applicable to implement

the local model. The required parameters and the

results of establishing the regional hydrodynamic

model are presented.

The required parameters for establishing the regional

hydrodynamic model are explained as follow: bed

roughness coefficient that is introduced to the model

by manning coefficient relations, numerical extent

parameters including disrupting parameters including

the areas of triangular elements, temporal steps of

solving equations, the geometric and depth

information as bathymetry input to the model, and

suitable boundary condition including tidal levels

from the performed predictions.

Fig. 1: the spatial extent of regional model applicable for modeling tidal flows

Modeling of Hydrodynamic Factors for Management of Coastal Hazards

28

To design the regional model, we have used the

available hydrographic data of Persian Gulf and

Oman Sea, at scale of 1:500000. The time scale in the

modeling is 2001 and it is supposed that the pattern of

tidal fluctuations for all other years is similar to this

period. This is confirmed by the parameters of

maximum, minimum, average and the frequency

represented in table 1 and 2 as a comparison between

the values in 2001 and a 19 years period. F3 shows

the time series of tidal level changes in one year on

the location of Khamir Port.

Local model:

The entire marine area between Gheshm Island and

mainland, i.e., the coasts of Hormozgan Province, is

considered as the extent of local model (Fig. 5). To

investigate the changes in sea level and in flow

velocity three points have been selected in the area at

depth of 0 meter (table 3).

RESULTS AND DISCUSSION

The general pattern of tidal flows in regional model is

represented in Fig. 4. When the regional model is

performed, the outputs of the model as the boundary

condition information are extracted to be applicable

for local model execution. It can also be stated that

rapid changes in wind direction in the area may have

influenced the characteristics of wind generated

waves (Sharifi et al., 2012).

Fig. 2: triangulation and bathymetry in regional model

Table 1: maximum and minimum of water level

Years Maximum Minimum Average

1997-2011 2.96 -0.33 1.61

2001 2.91 -0.25 1.60

Table 2: the percent frequency of water levels in 2001 and whole the 19 years

Water level <0.5 0.5-1 1-1.5 1.5-2 2-2.5 2.5-3

Frequency percent in 19 years 5.07 13.21 20.61 31.60 24.44 5.06

Frequency percent in year 2001 4.97 13.08 21.02 31.65 24.10 5.19

Int. J. Mar. Sci. Eng., 4(1), 25-36, Winter & Spring, 2014

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Fig. 3: one year time series of tidal levels in Chabahar Port

Fig. 4: the pattern of high tide and low tide flows in regional model

M. A. Nezammahalleh et al.

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Fig. 5: the local model for modeling of tidal flows and the location of the study area

Fig. 6: the position of selected points to present the results of local model of tides

Three points have already been extracted at 0 meter

deep to investigate initially the behavior of changes in

water level and flow velocity. The coordinates of the

selected points are presented in Table 3.

Table 3: the coordinates of selected points in local model

Point Longitude (Degree) E Latitude (Degree) N

1 55.876929 26.991681

2 55.911621 27.003431

3 55.941408 27.014841

The water level and flow velocity variations due to

tides are represented in Fig.s 7 and 8 for the selected

points in two months. The quantitative values of

speed variation of tidal flows are represented in Table

4 and frequency percentage of water levels in one

selected point is also represented in Table 5. In order

to specify the symmetric and asymmetric flows of

tide in the port, with the purpose to find out the

influence of tidal flows in transportation of coastal

sediments, the flow roses in the selected points were

created (Fig. 9). The general pattern of tidal flows in

local model is illustrated in Fig. 9. According to

Sharifi et al. (2012) we can also argue that the results

of MIKE21are more reliable in shallow areas and in

deep areas it may have unreliable results.

Int. J. Mar. Sci. Eng., 4(1), 25-36, Winter & Spring, 2014

31

Table 4: the characteristics of tidal flows in the selected points

Point Max. Level Min. level Average

level

Max. current speed

(m/s)

Average current speed

(m/s)

1 4.33 -0.11 2.25 1.06 0.54

2 4.35 -0.08 2.27 1.21 0.38

3 4.34 -0.06 2.27 1.12 0.42

Table 5: the frequency percentage of water level relative to C.D. in the selected point of 2

Water level <0.5 0.5-1 1-1.5 1.5-2 2-2.5 2.5-3 3-3.5 3.5-4 >4

Frequency percent of water

level in point 2 4.69 9.16 12.43 13.29 15.2 17.11 15.06 10.55 2.5

Fig. 7: time series of water level variations during two months at different points of the study area

Modeling of Hydrodynamic Factors for Management of Coastal Hazards

32

Fig. 8: flow velocity changes at the extracted points in the study area

Int. J. Mar. Sci. Eng., 4(1), 25-36, Winter & Spring, 2014

33

Fig. 9: the flow roses at the selected points

Fig. 10: the pattern of flow in high tide (upper fig.) and low tide (lower fig.) in local model

M. A. Nezammahalleh et al.

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The maximum extent of inundation by tides has been

ascertained for the area. According to the pattern of

tidal flows and based on the extents of increase and

decrease in the water level due to tides, it is possible

to detect the maximum advance of water onto the

coast in high tides. Figures of 11 and 12 show the

results of simulation of local model in different tidal

condition. The spatial advance of water towards the

coast is also shown in these two figures at different

times.

Fig. 11: the extent of inundation in the highest tide in the project area

Fig. 12: the extent of inundation in the lowest tide in the project area

Int. J. Mar. Sci. Eng., 4(1), 25-36, Winter & Spring, 2014

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To determine the maximum advance of water, due to

tide, onto the coast by the results of local model, the

maximum water level for each element has been

extracted. This indicates that in each given time

which element (areas of coastal land) is inundated by

the advance of water. (Fig. 13)

Fig. 13: the maximum water level occurred in each element of local model

CONCLUSION

The most important hydrodynamic factors that cause

coastline changes and advance of water onto the coast

in Persian Gulf have been recognized. These factors

include tidal fluctuations, wind setup, wave setup and

wave run up. These factors were also mentioned in

the studies of other researchers (Hubard and Dodd,

2002; Vose et al., 2007; Vousdoukas et al., 2009,

Modeling of Hydrodynamic Factors for Management of Coastal Hazards

36

Todd et al., 2009). Variations of water levels due to

tides are more examined in this research and the

maximum advance of water onto the coast was

modeled in tidal process on Khamir Port. Many of the

results have been verified by field surveys in the

study area. For the future studies, given the

methodology of the research, it is recommended to

execute modeling of the maximum advance of water

due to wind setup for the study area in different return

periods. The results of such a study may contribute to

determination of final advance of water and definition

of buffer for shoreline belt in the shore of Persian

Gulf.

REFERENCES

Gourlay M. R., (1992). Wave set-up, wave run-up

and beach water table: Interaction between surf

zone hydraulics and groundwater hydraulics.

Coastal Engineering 17, 93-144.

Johnston A., Slovinsky P., Yates K. L, (2014).

Assessing the vulnerability of coastal infrastructure

to sea level rise using multi-criteria analysis in

Scarborough, Maine (USA). Ocean & Coastal

Management 95, 176-188.

Leen De Vos, Peter Frigaard, Julien De Rouck,

(2007). Wave run-up on cylindrical and cone

shaped foundations for offshore wind turbines,

Coastal Engineering 54, 17–29.

Lykke Andersen T., Frigaard P., Damsgaard M.L., De

Vos L., (2011). Wave run-up on slender piles in

design conditions, Model tests and design rules for

offshore wind, Coastal Engineering 58, 281–289

Matthew E. Hubbard, Nick Dodd, (2002). A 2D

numerical model of wave run-up and overtopping,

Coastal Engineering 47 (2002) 1 –26.

Mikkel Fruergaard, Thorbjørn J. Andersen, Peter N.

Johannessen, Lars H. Nielsen, Morten ejrup,

(2012). Major coastal impact induced by a 1000-

year storm event, Scientific Reports 3, Article

number: 1051doi:10.1038/srep01051.

Mikkel Fruergaard, Thorbjørn J. Andersen, Peter N.

Johannessen, Lars H. Nielsen, Morten Pejrup,

(2013). Major coastal impact induced by a 1000-

year storm event, SCIENTIFIC REPORTS 3: 1051,

1-7.

Moeini M. H., Etemad-Shahidi A., (2007).

Application of two numerical models for wave

hindcasting in Lake Erie, Applied Ocean Research

29, 137–145.

Mojabi M.; Hejazi K.; Karimi M., (2013). Numerical

investigation of effective harbor geometry

parameters on sedimentation inside square harbors,

Int. J.MAr.Sci.Eng., 3, 57-68.

Nabil Touili, Juan Baztan, Jean-Paul Vanderlinden,

Idrissa Oumar Kane, Pedro Diaz-Simal, Luca

Pietrantoni, (2014). Public perception of

engineering-based coastal flooding and erosion risk

mitigation options: Lessons from three European

coastal settings; Coastal Engineering 87, 205-209.

Nezammahalleh, M. A., Yamani, M., Talebi, A.,

Pourhosseini, Z., and Alavipanah, S. K., (2013). A

NOVEL CRITERION FOR EARTHQUAKE RISK

ASSESSMENT, THE CASE OF BUSHEHR

CATASTROPHE IN APRIL 9, 2013. Int. Arch.

Photogramm. Remote Sens. Spatial Inf. Sci., XL-

1/W3, 301-304.

Peduzzi P., Chatenoux B., Dao H., De Bono A.,

Herold C., Kossin J., Mouton F., Nordbeck O.,

(2012). Global trends in tropical cyclone risk,

Nature Climate Change 2, 289–294.

Peduzzi P., Chatenoux B., Dao H., De Bono A.,

Herold C., Kossin J., Mouton F., Nordbeck O.,

(2012). Global trends in tropical cyclone risk,

NATURE CLIMATE CHANGE 2, 289-294.

Robins N. S., Pye K., Wallace H., (2013). Dynamic

coastal dune spit: the impact of morphological

change on dune slacks at Whiteford Burrows, South

Wales, UK. J Coast Conserv 4.

Sharifi F. S.; Ezam M.; Karami Khaniki A., (2012).

Evaluating the results of Hormuz strait wave

simulations using WAVEWATCH-III and

MIKE21-SW, Int. J. Mar. Sci. Eng. 2, 163-170

Sherman D. J., (2013). 10.1 Perspectives on Coastal

Geomorphology: Introduction, Treatise on

Geomorphology 10, Academic Press, 1.

Tabeshpour M. R.; Ataie Ashtiani BSeif.; M. S.;

Golafshani A. A., (2013). Hydrodynamic damped

pitch motion of tension leg platforms, Int.

J.MAr.Sci.Eng., 3, 91-98.

Todd L. Walton Jr., Robert G. Dean, (2009).

Landward limit of wind setup on beaches, Ocean

Engineering 36, 763-766.

Vousdoukas M.I., Velegrakis A.F., Dimou K.,

Zervakis V., Conley D.C., (2009). Wave run-up

observations in microtidal, sediment-starved pocket

beaches of the Eastern Mediterranean, Journal of

Marine Systems 78, S37–S47.

Zendegani A.; Narimannejad A.; MiriLavasani M. R;

Nasiri G., (2012). Safety assessment of offshore

structure, Int. J.Mar.Sci.Eng. 2, 239-248.

How to cite this article: (Harvard style)

Nezammahalleh, M. A *

.; Yamani, M.; Soltani, Sh.; Maldar Badeli, A.; Rastegar, A., (2014). Modeling of

Hydrodynamic Factors for Management of Coastal Hazards, Case Study: Khamir Port, Persian Gulf, Iran Int.

J. Mar. Sci. Eng., 4 (1), 25-36.