Luận văn thạc sĩ: Hydrodynamic assessment of a new master plan for Tam Quan port - Binh Dinh province

MINISTRY OF EDUCATION MINISTRY OF AGRICULTUREAND TRAINING AND RURAL DEVELOPMENT

AND TRAINING AND RURAL DEVELOPMENT

‘THUY LOI UNIVERSITY

oon Leann

PHAM PHU

HYDRODYNAMIC ASSESSMENT OF A NEW MASTER

Field: Coastal Engineering and ManagementField code : 62580203

MASTER THESIS

Supervisor : Assoc Prof Dr Mai Van Cong

I hereby certify that the work which is being presented in this thesis entitled,“Hydrodynamic assessment of a new master plan for Tam Quan port ~ BinhDinh province” in partial fulfillment of the requirement for the award of the Master ofScience in Coastal Engineering and Management, is an authentic record of my own

work carried out under supervision of Assoc Prof Dr Mai Van Cong ‘The matter

embodied in this thesis has not been submitted by me for the award of any otherdegree or diploma.

Ha Noi, December 15, 2016

Pham Phu

Implementing thesis study on hydrodynamic regime and sediment transport was achallenge but also an interesting and meaningful work to me From bottom of myheart, I gratefully acknowledge and give thanks to all individuals who gave me thepossibility to complete this master thesis.

First of all, I would like to expr my hearty and deepest gratitude to my supervisor

‘Assoc Prof Dr Mai Van Cong for his patience, timely advices, encouragement andvaluable supports 1 would gratefully thanks to MSe Nguyen Quang Duc Anh fromVINWATER for his constructive comments, providing data, guidance and practicalsuggestions to help me to accomplish thi study successfully.

1 would like to thank to Assoc, Prof, Dr, Tran Thanh Tung and Prof, Dr Thieu Quang‘Tuan who are main co-ordinators of this master program, making value contributionsto success in Master course Iam very thankful to all lecturers in Thuyloi University aswell as Delft University of Technology who imparted their valuable knowledge whichsupport me a lot in doing my thesis.

1 would like to thank sincerely to Assoc, Prof Dr Do Van Luong — Director and MSc.Do Canh Hao, vice ~ Director of Institute of Education and Applied Sciences central‘Vietnam who gave me a chance to study this master course

1 would like to thank all my classmates of this MSc course, all of them gave me the‘wonderful time during the course.

Last but never least, I wish to express my thanks to my organization, my colleaguesspecial thank and love go to my family and my dear parents for their support andencouragertents when I studied I dedicate this thesis to my family for their inspirationand support throughout my life; this research is simply impossible without you.

ACKNOWLEDGEMENT‘TABLE OF CONTENT!

LIST OF FIGURE:

LIST OF TABLES.

(CHAPTER 1 INTRODUCTION.

1.1 Background 11.2 Objectives ofthe study

1.3 Scope of the study1.4 Methods of the study1.5 Expected outcomes

33331.6 Chapters outline 4(CHAPTER 2 LITERATURE REVIEW 52.1 Overview of fishing ports 5$6

2.1.1 Concept of fishing ports

2.1.2 Classification of fishing ports.

2.1.3 Highlighted fishing ports in the world and Vietnam.

2.1.4 Current status of fishery of Binh Dinh province Ũ2.2 Overview of hydrodynamics of tidal inlets 15

2.2.1 Difference between tidal inlets and estuaries 12.2.2 Behaviour and hydrodynamics of a tidal inlet 182.3 Overview of deposition on tidal Mats 22.3.1 Density currents at estuary areas and deposition in rivers (Cat, 2003) 22

2.3.2 Sediment transport and deposition on tidal flats (Verhagen, 1999) 23

rea 24

2.4 Overview of the study

2.4.1 Previous studies in the study area 24

2.4.2 General information on the existing Tam Quan fishing port 26

24.4 Focus of this NHẢy _ se2.5 Overview of numerical models and the selection model 35

2.5.1 Introduction of numerical models 352.5.2 Numerical model selection 35

2.5.3 Introduction of MIKE 21/3 Coupled Model FM (DHL, 2012) 36

CHAPTER 3 FORMULATION OF PORT DESIGN AND PLANNINGCRITERIA & MODEL SET-UP 13.1 Formulation of port planning and design criteria, 41

3.1.1 General principles of planning anchorage area for boats and ships 413.12 Applied design standards, parameters for Tam Quan port and anchorageareas and its navigation channels 43.1.3 Formulation of port planning and design criteria according to hydrodynamic

aspects B

3.2 Natural conditions of Tam Quan fishing port area 463.2.1 Geographical location 463.2.2 Topographical characteristics 483.2.3 Geological charaelerisies " " 493.2.4 Hydrogeological conditions 503.2.5 Geology and geomorphology conditions 503.2.6 Climatic conditions sỊ

3.2.7 Oceanographie factors 33

3.3 Model set-up 563.3.1 Steps to set-up the model 563.3.2 Basie model input data 373.3.3 Model domain, computational mesh and boundaries 633.3.4 Hydrodynamic model parameters 643.3.5 Spectral wave model parameters 663.3.6 Sand transport model parameters " "53.4 Model calibration and validation, 683.4.1 Measured data 69

3.4.3 Calibration results 703.4.4 Validation result « so se 723.4.5 Discussion, 75CHAPTER 4 HYDRODYNAMIC ASSESSMENTS OF THE NEW MASTERPLAN FOR TAM QUAN PORT 764.1 Formulated modeling s ment of Tam Quan portnarios for hydrodynamicarea 164.1.1 For the existing situation 164.1.2 For the new master plan n4.1.3 Model extracted locations n4.2 Hydrodynamic assessments of Tam Quan port area based on riteri 794.2.1 Criterion 1, Avoid flooding in the port Land area 194.2.2 Criterion 2, To ensure calm wave condition in the port 844.2.3 Criterion 3 To ensure permissible currents for ship maneuvering 874.2.4 Criterion 4 Avoid deposition to maintain channel depths 944.2.5 Discussion tos4.3 Proposal of adjusted measure of the port entrance in order to fulfill port design

criteria " "5¬ " "M.

4.3.1 Proposal of adjusted measure 1054.3.2 Analysing the results of the adjusted measure 1074.4 Discussion "16CONCLUSIONS AND RECOMMENDATION

1 Conclusions us

2 Existing weakness HS

3 Further researches nọREFERENCI

APPENDIX A ~ Master plans of Tam Quan fishing port 124APPENDIX B ~ Results of the simulated scenarios for the exis ing situation 127APPENDIX C ~ Results of the simulated scenarios for the new master plan 31APPENDIX D — Results of the simulated scenarios for the adjusted master plan 135

Figure 2.1 Some pictures of Chimbote fishing port in Peru (Google Earth) 8Figure 2.2 Some pictures of Vladivostok Sea Fishing Port in Russia (Google Earth) 9Figure 2.3 The quantity and capacity of ships and boats in the whole province throughcách year (IEAS, 2016) 12Figure 2.4 The quantity and capacity of ships in Hoai Nhon district through the years

(EAS, 2016) B

Figure 2.5 Some pictures of Quy Nhon fishing port in Binh Dinh province(photographed in November 2015) 4

Figure 2.6 Some pictures of De Gi fishing port in Binh Dinh province (photographed

in Match 2015) sos MA ".Figure 2.7 Morphodynamics of seasonally closed coastal inlets at the central coast of‘Vietnam (Tung, 2015) 18Figure 2.8 Ebb (E) and flood (E) tidal channels During flood the water might

‘overshoot the bend leading to flood chutes, this process is schematized by the arrows(Van Veen, 1950) 20

Figure 2.9 Some pictures of Tam Quan fishing port (photographed in November 2012)27Figure 2.10 Digitizing the channel route for planned ships (IEAS, 2016) 32Figure 2.11 The location of Thien Chanh and Go Dai fishing ports 3

Figure 3.1 The altitudes and depths, heights in front of the pier (Giap et al., 2010b) 44Figure 32 The location of the study area a7Figure 3.3 Wave roses in the nearshore and offshore of Tam Quan area, “Figure 3.4 Wave height in the offshore of Tam Quan area from 1988:2013 35Figure 3.5 Wave period in the offshore of Tam Quan area from 198822013 5sFigure 3.6 Wave direetion inthe offshore of Tam Quan area from 1988:2013 56Figure 3.7 The topographic map of surveyed area (Duc et al, 2015) 58Figure 3.8 The bathymetry of study area used to simulate in MIKE 21 model 58

Figure 3.10 Design flood discharge hydrograph (P=5%) at Xuan Thanh bridge and theupstream of Thien Chanh bridge 60

igure 3.11 Wave roses at the border point of deep water wave ofTam Quan area 61

Figure 3.12 Model domain and computational mesh included triangular andquadrangular elements 6Figure 3.13 The location of observation stations (background map sourced by Google

Earth) 69

Figure 3.14 Comparison between calculated and measured water level at PL 7

Figure 3.15 Comparison between calculated and measured water level at P2 7Figure 3.16 Comparison between calculated and measured wave height at P4 72Figure 3.17 Comparison between calculated and measured wave period at P4 72Figure 3.18 Comparison between calculated and measured mean wave characteristic atPa nFigure 3.19 Comparison between calculated and measured water level at PL T3mì between calculated and measured water level at P2 Bigure 3.20 Compari

Figure 3.21 Comparison between calculated and measured wave height at P3, 14Figure 3.22 Comparison between calculated and measured wave period at P3 4Figure 3.23 Comparison between calculated and measured mean wave characteristic atP3 75

Figure 4.1 The bathymetry of new master plan and the extracted locations of theresults from Mike 21/3 FM model 78Figure 4.2 Water level in the port area during the flood peak period (at 0:00 AM

October 11, 2013) with the existing master plan (T) and the new master plan (B) 80

1 between SC3_PLO and SC6_PLI at 10 points 82Figure 4.3 Comparison of water le

Figure 4.4 Significant wave height field in the Southwest monsoon period with theexisting master plan (L) and the new master plan (R) 85Figure 4.5 Significant wave height field in the Northeast monsoon period with theexisting master plan (L) and the new master plan (R) 86Figure 4.6 Spring current field (T) and ebb current field (B) in the Southwest monsoonperiod with the existing master plan 88

Figure 4.8 Spring current field (T) and ebb current field (B) in the Northeast monsoonperiod with the existing master plan 9Ị

Figure 4.9 Spring current field (T) and ebb current field (B) in the Northeast monsoonperiod with the new master plan %

Figure 4.10 Total bed level change in a month in the Southwest monsoon period withthe existing master plan 94Figure 4.11 Total bed level change in a month in the Southwest monsoon period with

the new master plan 95

Figure 4.12 Total bed level change in a month in the Northeast monsoon period withthe existing master plan 9Figure 4.13 Total bed level change in a month in the Northeast monsoon period withthe new master plan 98Figure 4.14 Total bed level change in the flood season with the existing master plan.99Figure 4.15 Total bed level change in the flood season with the new master plan 100)Figure 4.16 Comparison of bed level change between the existing master plan and thenew master plan at 10 cross-sections along the channel routes 103Figure 4.17 The adjusting plan ground and the main current directions 106Figure 4.18 Water level in the port area during the flood peak period (at 0:00 AM

October 11", 2013) with the adjusted master plan, 107

Figure 4.19 Significant wave height field in the Southwest (L) and Northeast (R)‘monsoon periods with the adjusted master plan 109Figure 4.20 Spring current field (T) and ebb current field (B) in the Southwest‘monsoon period with the adjusted master plan 110Figure 421 Spring current field (T) and ebb current field (B) in the Northeast‘monsoon period with the adjusted master pan can MFigure 4.22 Total bed level change in a month in the Southwest (T) and Northeast (M)‘monsoon periods and in the flood season (B) with the adjusted master plan HẠFigure 4.23 Comparison of bed level change between the new master plan and theadjusted master plan at 03 cross-sections along the AB channel route 14

‘Table 2.1 The current status of changing ships and boats in the whole province througheach year (IEAS, 2016) in‘Table 2.2 The current status of boats and ships in Hoai Nhon district through the years

(IEAS, 2016) 12

Table 2.3 The calculated ship parameters « « 30

Table 3.1 Requirements for calm wave condition in the port basin under Japaneseregulations (OCDI, 2002) 45Table 3.2 The statistic table of the wave parameters in calculating the sediment

transport 2

‘Table 3.3 The location of observation stations, times and contents of observatioa 69Table 3.4 The error assessment results of the model calibration a‘Table 3.5 The error assessment results of the model validation Tà

‘Table 4.1 The extracted co-ordinates ofthe results from Mike 21/3 FM modtl 78Table 4.2 The summarized result of the flooded area of the plans 81Table 4.3 Results of water level at locations in the flood season ($C3_PLO&SC6_PL1)

83Table 4.4 The summarized results of the wave height in Tam Quan port area 86

Table 4.5 Results of water level at locations in the flood season (SC6_PL1&SC9_PL2)

108

SC PLst

Spectral Wave

Top

1.1 Background

Binh Dinh is a coastal province of the South Central Vietnam Its natural area is

6,050.58 km? and its population is of about 1.5 million people With 134 km along its

coastlines, and tens of thousands of hectares of the lagoon and reservoirs, these arefavourable conditions for the development of the local fisheries sector There are fivecout of eleven districts of the province (Hoai Nhon, Phu My, Phu Cat, Tuy Phuocđisriets) and Quy Nhon city having marine economy activities The fisheries sectorthas an important role in socio-economic development of the province In recent years,fishery production has gained remarkable achievements.

Hoai Nhon district is located in the North Pole of Binh Dinh province, with a coastlineof 23 km, a population of 206,000, among which 72,721 are in coastal communes,longstanding experience of fi ng, aquaculture and seafood proces ing, and fisherylogistics services To exploit the advantages of the sea, the local government hasdetermined that marine economy is the key advantages of the district in the nearfuture,

‘The advantages of geographical location, workforce and a long tradition of fishing andaquatic resource exploitation, Bình Dinh province in general and Hoai Nhon distit inparticular have identified marine economic development to be a priority for speeding

up socio-economic development in the local, inereasing income for local people and

contributing tothe protection of the sovereignty and security ofthe country’s islands.Decision No 1976/QĐ-TTg, dated November 12, 2015 of the Prime Minister on the

planning system of fishing port, storm shelters for fishing ships until 2020 and

orientations to 2030 also identified as Tam Quan port as a level? fishing port with a

However, the construction of infrastructure serving the maritime economy is notcommensurate with the potential ofthe district Today, Tam Quan Bac is a fishing portwhere boats anchoring and fishing logistics services only Hoai Nhon district andduring the rainy season was received by 200-300 ships of Quang Ngai province andPhu My, Phu Cat district 000 ships The‘The existing port can only receive 800:

access channel is often filled with about 50,000-100,000 m* sediment yearly, causing

difficulties for boats and ships to move in and out the port The infrastructure forfishery is still limited for accommodating big ships,

During the long development of this fishing port, fishing docks have been attached tothe riverside fishing village, crowded residential, tight space; facilities procurement,processing and supply of oil and necessities are interspersed in residential areascausing environmental pollution, lack of safety guarantee for people and fishing ships;travel conditions, narrow roads that prevent from producing flow, and reduction oftraction in attracting investment from society.

Considering the above factors, People’s Committee of Binh Dinh province hasadvocated for having a detailed planning of fishing port, anchorages and storm

sheltets, fishing logisties services of Tam Quan (in Document No 237/TB-UBND,

dated October 20, 2015) The project’s main aim is to facilitate economic developmentof the region, but not yet for a second focus on national security in terms of provishelter for warships

‘Moreover, to implement the national objectives to 2020 and vision to 2030 concerningthe sea-based economy development, it should be focused on strengtheninginfrastructure of sea ports to serve better military aims and to ensure safety for ships in

all weather cond ns Thus, a study on master plan of Tam Quan port - Bình Dinhprovince is urgent This has been implemented recently by Binh Dinh province under afeasibility study project.

‘This study focuses on assessments of a proposal master plan on the following aspects’sediment deposition in the port area and the port entrance; hydrodynamic condition in

and around the port area and to check if these conditions are committed to port design

operation criteria,

- Analysis of hydrodynamic conditions by modelling interactions of waves and

‘currents with the existing proposal of port infrastructures.

-Ai sssment of hydrodynamic conditions (currents, waves, sedimentation) in the port

areas and port entrance to see if these are met basic port design criteria.

~ Proposal of measures or adjustment of the existing master plan in order to fulfill portdesign criteria,

1.3 Scope of the study

‘This study is to focus on assessment of hydrodynamic condition for the situation ofhaving the existing port master plan with a direct concern to waves, currentsconditions and deposition possibilities in and around the port area Other aspects suchas erosion or change of coastal morphology condition of the port vicinity,environmental condition are not within scope of this study.

1.4 Methods of the study

‘The following methods have been applied to this study:

- Analytical method: formulation of port design criteria to estimate sediment volume

exchange due to waves and tides.

- Modeling method: using 2D hydrodynamic model (Mike, Delfi3D, Swan, ete.) toanalyze, assess the interactions between waves and currents with the proposal portinfrastructures,

This thesis is structured in 5 chapters, includes:Chapter 1: Introduetion

Chapter 2: Literature review

Chapter 3: Formulation of por design and planning eiteria & model set-upChapter 4: Hydrodynamic assessments ofthe new masterplan for Tam Quan portConclusions and Recommendation

2.1 Overview of fishing ports2.1.1 Concept of fishing ports

According to Scheffezyk (2008), the importance of the application of clearlyformulated definitions for the purpose of policy setting and management planning is

widely acknowledged Therefore, most essential definitions are given below.

slematic approach, a fishing port is a system combining infrastructurehuman resources, and management concepts, dedicated to the purpose‘of servicing the fishing fleet, the requirements of the fish industry and thedevelopment of the fisheries sector as a whole.

On operational approach, the definition of port operations considers that afishing port serves as an industrial zone for unloading, processing, storage and.marketing of fish, as well as for maintaining and servicing the fishing fleet Inconsequence, a fishing port is an integral part of the national fishing industry,‘an important element in promoting the and an operation base forthe viable and sustainable conduct of the

= On functional approach, the term port functions include all activities carried outby the port for operation and maintenance of the infrastructure facilities, for‘organization and conduct of port services required by vessels, fish processors.

and buyers, collection of port and service fees, and administration,

According to document from Wikipedia page, a fishing port is a port or harbor forlanding and distributing fish It may be a recreational facility, but usually commercial‘A fishing port is the only port that depends on an ocean product, and depletion of fishmay cause a fishing port to be uneconomical In recent decades, regulations to savefishing stock may limit the use of a fishing port, perhaps effectively closing it,

According to Pham Van Giáp et al (2010a), the system of fishing ports and landisites are classified into 03 categories: central territory fishing port, local fishing portand landing sites according tothe following criteria

= The building location;

= The Function ofthe port;

= The nature ofthe port,

~The infrastructure;

= The equipment of the port;

~The attractive zone ofthe port~The transport to go to the port:

= The amount of designed seafood through the port;= The ports largest ships:

= Numbers of vessels go in and out the port per year

Under the current regulations, fishing ports are divided into 02 categories: level-lfishing port and level-2 fishing port, according to the following criteria (Decree No,

80/2012/ND-CP, 2012)

~The building location and the Funetion ofthe pot

= The equipment and the chain of cargo handling ofthe por

= The area ofthe por and logistics base for fishing;

= The amount of designed seafood through the por.

Therefo „ the classification of Tam Quan fishing port also based upon twoviewpoints According to Pham Van Giap et al (2010a), Tam Quan fishing port is thelocal fishing port, until 2015 it has the capacity scale of 80 times/day with the largestsized ships of 400 CV and the amount of seafood products through the port of 18,000tons/year Classification according to the decree No 80/2012/NĐ-CP which namely bydecision No 1976/QĐ-TTg on November 12, 2015 of the Prime Minister approving to

adjust the planning of the system of fishing port and storm shelters for the fishingships until 2020, vision to 2030 identified: “Tam Quan sea por is the level-2 fishing

port with the capacity scale to response for 200 times of 400 CV ships and the amour

‘of seafood products through the port of 20,000 tons/year; simultaneously, Tam Quan

storm shelter is also the regional storm shelter for fishing ships with the seale of 1,200

ports The database developed as part of that work provides port/provinee-speci

landing data for 47 countries, with eni corresponding to 948 individual ports and107 state provinces, which provide the most specific data when individual port data‘could not be obtained The proportion of landings for the key species group per port,the type of landings, and the level of data robustness are also listed At an aggregatednational level, the largest level of total landings occurs in China, with 13.9 millionmetric tons, followed by Indonesia (5.7 million metric tons), U.S (5.1 million metrictons), Peru (4.9 million metric rons), and Russia (4 million metrie tons),

Here is some information about typical fishing ports in the world.

1, Chimbote fishing port in Peru

Chimbote fishing port is located on the coast in Chimbote Bay, south of Trujillo and422 km north of Lima, This is the largest fishing port in Peru and also is ranked thefirst in the world about fish landings by the study of Huntington et al, in 2015, Somerecent shots of the port for an overview are presented in Figure 2.1

Chimbote has more than 30 fish factories, and has some of the world’s finest packing equipment More than 75% of Peru's fishing industry occurs in Chimbote, TheChimbote — Huallanca rail line, built in 1922, serves as a railway for coal and ironmines on the interior and a railway for the river valley by transporting rice, cotton,sugarcane, and bananas (Chimbote ~ Peru, 2015)

fish-2 Vladivostok Sea Fishing Port in Russia

‘Vladivostok sea fishing port is located on the southern shore of the Golden Hom bay,‘This is the largest fishing port in Russia and also is ranked the second in the world

about fish landings by the study of Huntington et al in 2015, Some recent shots of the

port for an overview are presented in Figure 2.2

The port is locating on 10 berths (of depths from 9.8 up to 12.4 m.) on southern coastof a nonfreezing Gold Hor Bay, The extent of moorings is 2,020 m The general area

of port consists of more than 323,700 m* (Vladivostok fishing port, 2015).

The Vladivostok Sea Fishing Port is the universal reloading complex that is capablepart from fish products handling to carry out cargo operations with such cargo classes

as a timber, metal, fertilizers, cellulose, combustive-lubricating materials, ete There

are three covered warehouses for products, cellulose, cardboard, packages, ferti

and other dry cargoes Their useful storage space makes more than 58,000 m? All

utilities are heated and supplied with effective system of ventilation that maintaintemperature inside them from 0 up to 20 Celsius degrees at any time of the year It is

possible to place up to 400 thousand tons of various eargoes atthe open storage spaces

on the berths (Vladivostok fishing port, 2015).

Capacity of port makes more than 5 million tons of cargoes and 200 thousand

Figure 2.2 Some pictures of Vladivostok Sea Fishing Port in Russia (Google Earth)2.1.3.2 In Vietnam (Giap et al, 2010a)

Detaled planning of the system of fishing ports, fishing markets and landing sites in

Vietnam to 2015, identified 206 structures of fishing port and landing site, the total

seafood products through the system of fishing port and landing site nationwide by2,401,155 tons/year In which:

~ 19 structures of central teritory fishing port with the total seafood productsthrough by 750,000 tons/year;

= 85 structures of local fishing port with the total seafood products through by

Considering overall the planning of the system of fishing ports, fishing markets and

landing sites to 2015 and the adjusted planning of storm shelters for fishing vessels‘until 2010 and vision to 2020 approved by the Prime Minister that there are 69structures of fishing port and 31 structures of landing site can be combined with stormshelters for fishing vessels when construction investment.

2.1.4 Current status of fishery of Bình Dinh province

Coastal districts of Binh Dinh province mostly rey on fishery from the Vietnam EastSea With a long coastal ines and high populated density along the coasts, thus BìnhDinh is known as of the most sea food exploitation and production in VietnamNumber of ‘hing family and thus fishing ships (boats) has been increasing rapidlyduring the last 10 years Tables 2.1 & 2.2 demonstrate the trend of development basedfon number of ships.

Along the coast of Binh Dinh province has 03 large inlets and 03 spots of fisheries:Tam Quan, De Gi and Quy Nhon Besi

fisheries villages formed on capes, along lagoons and Nhon Chau Island commune.'s, there are also 7 small landing sites with 26

Formerly, the fishing ports and fi ing wharfs of Binh Dinh province in generally areall spontaneously formed, the fishing wharf is closely connected with the fishingvillage; there have not been any works of wharfs or piers and any rear service

‘The phase from 2002 to 2006, supported from the Central and the provincial capitalsources, the fishing ports of Quy Nhon, Tam Quan, De Gi and Nhon Chau island werealternatively invested on upgrading, dredging to open the channels, bayous, toconstruct the jetties, the anchorage pillars, piers, the yard systems, the warehouses, theelectric supplying system, the fresh water supply, simultaneously and attractedsocialization from the powers of investing and constructing the cold storage, the petrolsupplying station, the necessities and the newly ships and boats building and fixingfoundations,

However, because the quick growth speed of the ships and boats quantity, especiallythe ships with high capacity so the fishing ports are overload, averagely each fishingport can only receive from 60-100 ships/day, when the demand goes up 150/200shipsday at the peak On the other hand, due to not constantly being dredged, thechannels or bayous are deposited, and the big ships are difficult to go in and out or

have accidents of crash, shipwreck, strand, causing many losses of human beings andproperties of the fishermen The anchorage is narrow, not enough necessary deepWhereas the sizes of ships are bigger and bigger and the depth of waterlines is higherand higher under the weight of the ships Therefore, a significant numbers of fishingships in the province do not return the home fishing port but approach at the ports ofNha Trang, Ninh Thuan, Phan Thiet and Vung Tau to sell fish and receive petro, ice,necessities, which causes difficulties for fish catching activities and reduces theaquatic product yield of the port, decreases the motivation of developing the activitiesof fishery logistic services and aquatic product process in the province.

The fishing ships of Bình Dinh provin

districts of Hoai Nhon, Phu My, Phu Cat, Tuy Phuoc and Quy Nhon, in which Hoai-s mainly in the coastal five

Nhon is the district with the most powerful ship team with 2,458 ships, taking the rateof 36% of the provincial ships total (6,909 ships) and gathers many ships with the‘great capacity for fishing offshore with the engine installing capacity of 816,386 CV‘equal (0 63% of the provincial ships and boats total (1,301,587 CV),

Table 2.1 The current status of changing ships and boats in the whole province

through each year (IEAS, 2016)

‘The annual quantity of ships and boats of whole

No Content province

2005 | 2010 | 2013 | 2014 | 20151 [Total ships of whole prov.| 8200| 9452 &486| 7785| 6,9091 Ships under 50 CV 4361| 2,645, 2236 3,2302 nips 50.90 ev 1888| 3289) 2257 317

4 hips 150-400 CV 40L 1512) 1,692 1,652

II Total capacity 251,467| 614,244) 992,815 1,149,201 |1,301,587

‘The annual quantity of ships and boats of Hoai

No Content Nhon distri

process, in 2002, Ham Tu wharf was invested in upgrading to become Quy Nhonfishing port Some recent shots of the port for an overview are presented in Figure 2.5.‘Main feature: providing key facilities for fishing ships mooring and creating shelterarea for fishing boats which are operating in the surrounding sea during storm,

Capacity: Quy Nhon fishing port is a national focal port (type 1) of the South Centralof Vietnam The port has the ability to provide storm shelters For about 2.000 ships andit has the capacity scale of 150 times/day and the largest sized ships of 600 CV Theamount of seafood products through the port is 41,482 tons/year.

2 De Gi fishing port

De Gi fishing port is located in De Gi estuary, belongs to Cat Khanh commune, PhuCat district, Binh Dinh province Some recent shots of the port for an overview arepresented in Figure 2.6.

Main feature: providing key facilities for fishing ships mooring and creating shelterarea for fishing boats which are operating in the surrounding sea during storm.

Capacity: De Gi fishing port is a local fishing port The port has the capacity seale of120 times/day and the largest sized ships of 300 CV The amount of seafood productsthrough the port is 17,000 tons/year (Giáp et al., 20104).

2.2 Overview of hydrodynamics of tidal inlets2.2.1 Difference between tidal inlets and estuariesEstuaries

‘There are many ways in which estuaries have been defined, but by their very nature asplaces of transition between land and sea, no simple definition readily fits all types ofestuarine system, Perhaps the most widely used is that proposed by Pritchard.Pritchard (1967) defines an estuary as a semi-enclosed coastal body of water whichhas a free connection with the open sea and within which sea water is measurably

diluted with fesh water derived from land drainage,

However, due t the shortcomings of the definition of Pritchard, many scientists haveproposed of using a more proper definition than that of Fairbridge which was stated in1980, Fairbridge (1980) defines “An estuary isan inlet of the sea reaching into a rivervalley as far as the upper limit of tidal rise, usually divided into 3 various parts: (a) the

ow sea part or the estuary part connecting with the ocean; (b) the medium riverestuary part, where the main mixture of sea water and fresh water are taken place; and(c) the high river estuary part, dominated by the fresh water but still with the impact oftide, The limit among these parts are not fixed and oscillated under the fresh wateramount poured from the river

Due to the connection with the sea, the water level in an estuary is affected bydischarges from upstream rivers and tides Estuaries can be considered as dynamicareas as changes in morphology can be seen at different time and spatial scales,‘Variations in tidal prism, river discharges, relative sea level rise and the availability of

015).sediment result in various characteristic types of estuaries (Julien,

In real estuaries the influence of river runoff is considerable, and a major contributionto the morphology of the area, Estuaries consist very often of mud, although also sandcan be found, Because of geological featu

shapes The Wester Scheldt in the south of the Netherlands and the Elbe estuary in estuaries may have very particular

Germany are rather standard, but for example the Tagus estuary in Portugal is fullygoverned by a rock-formation near the mouth Therefore, this estuary has a narrow

‘mouth and a much wider basin inside (Verhagen, 1999),

In Vietnam, the estuaries at Hong and Cuu Long river mouths are lobate-shaped,whereas the estuaries in the central are diversified For instance, the area in the southcentral Vietnam, where the mountains extend close to the sea, the estuaries changeonly litle and flow on the igneous rock beds, whereas the estuaries in the north (from

‘Thanh Hoa to Quang Tri) and in the south central Vietnam from Phu Yen to Binh

‘Thuan, the estuaries develop on the sedimentary floor of the sea or the sea river andthe estuaries are shut or opened under the circle of the flooding season-exhaustingseason (Cat, 2002).

Tidal inlets

According to Kee đAngremond and E,T.J.M Pluim-Van der Velden (2001), a tidalinlet is a short, narrow waterway connecting a bay, lagoon or similar body of waterwith a large parent body of water Tidal inlets often exist at places where there arebreaks in a barrier coast According to Verhagen, H.J (1999), an estuary is a more or

less wide mouth of a river, while a tidal inlet is a connection to the sea where riverdischarge is zero So, in case of a tidal inlet there are no effects of density currents,there is no variation of discharge due to high river runoff, In general one maydistinguish two types of tidal inlets, the barrier-island inlets and the lagoons.

Ata coast with barrier-island inlets there are gaps between the islands, through whichthe water flows in and out to fill the intertidal area between the islands and themainland Usually in this case the environment of the inlet consists mainly of sand,although in the tidal flats behind the barriet-island often a lot of mud can be found, Incase of a lagoon (or a bay) the environment can be either sandy or muddy Because inthese có the landward extend of the lagoon is considerable, these lagoons and bays:show often resemblance to estuaries,

Wherever wave power is relatively low (so behind barrier islands or inside an estuary)and the tidal range is moderate to large, then tidal flats, rather than beaches, are likelto develop, Tidal flats usually have very low gradients, n the order of 1:1,000 at thelandwards edge, and are composed predominantly of sills and elays, instead of sands‘The large tidal range and shallow gradients mean that the waves do not break on any

‘one part of the flats for a Tong time and, consequently the flood and ebb tidal currents

‘are more effective at sediment transport that isthe wave aetion.

‘There are some exceptions where tidal flats occur on coasts facing the open sea, ¢ Surinam on the north-east coast of South America, or Tam Giang lagoon area ofVietnam, In such cases, tidal-flat development is encouraged by a combination of

exceptionally high concentrations of fine-grained, suspended sediments in the coastal

waters and a very gentle offshore slope Elsewhere, tidal flats are usually restricted toregions in the shelter of features such as spits, barrier islands, and coastal embaymentsoor estuaries Fi ire 2.7 below is typical example about morphodynamic of seasonallyclosed coastal inlets at the central coast of Vietnam.

According to the above features, Tam Quan estuary area has the nature of both a rivercestuary and a tidal inlet However, according to the study of Duc et al (2015) defined:

“Because Tam Quan channel connects the sea to the inside lagoon, Tam Quan estuaryshould be seen as a tidal inlet”.

tides and the lowest low tides, also known as spring tides Neap tides refer to the

situation where the sun and moon are at right angles, resulting in the lowest high tidesand the highest low tides The duration of one spring-neap tidal e

14.8 days (Julien, 2015),

cle is approximately

Tidal asymmetry (Julien, 2015)

‘When describing a tidal wave, a distinction can be made between movements inhorizontal and vertical direction, A horizontal tide refers to the tidal currents ordischarges and a vertical tide to the rise and fall of the water level The relationshipbetween the horizontal and vertical tide depends on the shape of the cross-section(hypsometric effect) In a rectangular cross: tion, a (wo times larger vertical tideresults in a two times larger horizontal tide However, in an area with deep channelsand large intertidal storage areas, the relationship between water level and flowvelocity is not linear.

As a tidal wave propagates into an estuary, itis affected by the friction from the bedand the narrowing width Due to the decreasing water depths and narrowing of theestuary, the tidal wave slows down and the amplitude inereases The friction of the bed‘causes a decrease in tidal amplitude, The net effect differs per situation

Neglecting friction and assuming a prismatic channel, the propaga ion velocity of a

tidal wave is given by c= gh = Jedi, +8) This means that the speed of the tidal

wave is larger during high tides than during low tides The tidal wave is deformed andđiẾ@rs from a sinusoidal curve, The resulting saw-tooth-shape profile canmathematically be described by the inclusion of higher harmonics or so-calledowenides The higher harmonics are generated by the interaction of basic tidalcomponents causing non-linear effects, These effects grow in shallow water where theratio amplitude over water depth increases.

Due to faster propagation of the tidal wave during high water with respect to thepropagation during low water, the rising period is shorter than the falling period In

this case, larger flood velocities occur because the same amount of water is moved in

and out of the system during a tidal cycle This system, in which the period of thewater level rise is shorter than the falling period, is called flood-dominant For deepchannels and large intertidal storage areas, the opposite occurs Due to the low waterdepths in the intertidal areas, the propagation of the high tide is slowed down, Thesituation where the ebb velocities are larger than the flood velocities is referred to asan ebb-dominant system.

Special types of (tidal) waves are progressive waves oF standing waves where the

phase difference between the surface elevations and the velocity is 0” and 90?

respectively Because the tidal wave is affected by frietion, a phase difference of

approximately 45° (corresponding to approximately 3 hours) is mainly found in

estuaries This means that the mean water level during flood is higher than the meanwater level during ebb,

Flood and ebb channels

Like in a river, the channels are meandering, This means that they have the tendencyto erode in the outer bends, and to accrete in the inner bends Also the outer side of thebend is much deeper than the inner side At those places where one bend meets thefollowing bend the deep part has to move from left to right (or vice versa) andconsequently there is no deep part This place is called a saddle or threshold in the

ind caus

estuary, often problems for navigation, These are the places which have to

be dredged periodically to allow ships to sail into the estuary (Verhagen, 1999),

Considering a straight channel connected to the sea, during each tidal cycle waterflows in and out of the channel A small deviation in a straight channel triggers a

positive feedback mechanism called meandering Due to curvature-induced secondary.flow the outer bend will erode and deposition will occur at the inner bend Especiallythe ebb channels are subjected to this meandering process During flood the waterenters the channel and might overshoot the bend due to inertia (see Figure 2.8).

Figure 2.8 Ebb (E) and flood (F) tidal channels During flood the water mightovershoot the bend leading to flood chutes, this process is schematized by the arrows

(Van Veen, 1950)

‘water during low tide, during ebb the water will flow particularly through the ebbchannels, Because of this flow concentration, the ebb channels will be deeper andmore curved than the flood channels (Van Veen, 1950) The resulting landscape ofmeandering channels and tidal flats is characteristic for an estuary basin.

2.2.2.2 Waves

In order to describe the motion of a wave in a mathematical way, it is common use to.simplify it into a sinusoidal wave, Linear wave theory (Airy, 1845) is, among others,‘based on the assumption that the surface displacement is relatively small and the waveis only affected by gravity According to Airy, a wave can be described u ng a

dal expression (as in equation 2-1) and travels by the phase velocity c (asindicated in equation 2-2) This propagation speed is defined as the ratio between wavelength L and wave period 7 The instantaneous water level 1 is a function of theamplitude a=H/2, the radian frequency @=27/T and wave number k=2/Z1,

(wave height, period, propagation ditection) are a function of the prevailing wind

(speed, fetch) and water depth At smaller water depths waves start to dissipate theienergy, which results in the stising up of sediments Tis introduces the concept of\waves stirring up the sediment and the current transporting it, An important parameterfor describing waves is the signi sant wave height (see equation 2-3), which is definedas the average wave height of the highest one third of the waves Another way todetermine the significant wave height is using the wave spectrum,

#, 23)

2.2.2.3 Tidal prisms and the stability of the inlet (Verhagen, 1999)

Ấn a tidal inlet there is usually a balance between the transport of sediment along the‘coast by the longshore transport, and the flushing capacity of the inlet If the flushing

capa ity is too low, the longshore transport will eventually close the inlet, IF theflushing capacity is very large, the sediment coming from the coast will all betransported into the intertidal areal between the barrier islands and the coastline.

Bruun (1978) has investigated this stability factor in detail, and he came to theconclusion that the inlet stability is defined by the relation P/M In this relation, Pi

the tidal prism (in m’) and M,„„ is the total Longshore transport (in m'/yeat) Mia is

the transport from both directions of the inlet added up Be aware that this stability‘number is not dimensionless.

However, one should realize that in case of significant river runoff (thus in fact anestuary instead of a tidal inlet) the effect of the river runoff has to be added to the tidalprism Numerically this is not so easy

In case of an estuary where during part of the year the discharge of the river isconsiderable, while during the rest of the year the discharge is negligible, one has to

determine two different stability numbers The conclusion can be that during the dry

season the inlet is unconditionally unstable, and will certainly close, while during thewet season the inlet is unconditio ly stable This happens in areas with a clearmonsoon climate, like in India and Sri-Lanka,

2.3 Overview of deposition on tidal flats

2.3.1 Density currents at estuary areas and deposition in rivers (Cat, 2002)

A reviewed point is an upper limit of the tidal current when entering the thay,

Because the salt and fresh water has am ixture at various levels, various locations,

which is the cause for generating the density current The current is created by thedifference from the density is called the density current.

The water level oscillation in a tidal period is the cause which makes a salt wedge‘move up and down, The most direct consequence of the salt wedge movernent into theriver is the sedimentation process at the estuary The current close to the bottom

changes strongly by the appearance of the salt wedge The top part of the salt wedge,the current has a direction towards the sea, whereas in the salt wedge the current has 4irection to run into the river withthe fairly small speed Because the bed velocity atthe top wedge must to equal zero, the sedimentation process will occur at this area Atthe estuaries which have small tidal effects with the stable wedge existence, thesedimentation can make the river bed rise up significantly It is the role of the salt‘wedge that there is change of er density here, which is the major cause for thesedimentation phenomenon.

‘There are very few technical measures with the high economic significance aiming atcontrolling the salt wedge situation to invade into the river Majority of the technicalmeasures only concentrate on the small areas with the high economic significance suchas the channel and port area Be able to recognize that being able to limit the invadingprocess of the salt wedge if there is a reduction of salt water depth or an increase offresh water amount which runs out from the river.

2.3.2 Sediment transport and deposition on tidal flats (Verhagen, 1999)

Tidal flats are flat and almost featureless areas which occur along some stretches ofcoastline and within estuaries They are often backed by areas of slat-marsh anddissected by a network of tidal channels Seawater enters the tidal channels on theflood tide, gradually filling them and the tide risus until the water spills over andfloods the adjacent flats, After the slack water of high tide, the water drains back offthe flats and through the tidal channels until the entire tidal flat is exposed once more,‘This patter of water movement, and the interaction between tidal currents and waveaction, has important con:

the tidal flat

‘qu s for the transport and distribution of sediment on.

In the simplest situation, there is a seaward progression in grain-size from dominated sediments at the landwards end to sand-dominated sediments at theseawards end The low tidal flats are submerged for most of the tidal eyele and aresubjected to strong tidal currents and minor wave action during this period Even at theslack water of low and high tide, there is some sediment disturbance by waves,Consequently, muds are kept in suspension and sediments are deposited only from thebed load.

mud-The mid-flats are submerged and exposed for roughly similar periods mud-They areusually submerged during the mid-tidal cycle when tidal currents may reach their‘maximum speeds and so the sediment may be affected by these strong tidal currents,although wave action is very weak Bed load transport and deposition of sands areagain dominant, accompanied by the development of current-formed ripples However,during the period of slack high water, fine muds held in suspension are able to settleout, forming characteristic mud drapes over the surfaces of the previously formedripples

‘The high tidal flats are submerged only at high tide when current speeds fall to zero.No bed load transport or deposition occurs but during the slack water period mudssettle out of suspension to form the mud-flas, When the tide turns, these muds will beeroded only ifthe ebb current generates a shear stress atthe bed which is greater thandiment, Because muds are cohesivethe critical shear stress required to erode thị

sediments, there are difficult to erode after deposition.2⁄4 Overview of the study area

2.4.1 Previous studies in the study area

In 2010, an author group of Pham Ba Trung, Le Dinh Mau and Le Phuoe Trinh had anarticle for studying on “Sedimentation issue at the estuaries of Sa Huynh (Quang Ngaiprovince), Tam Quan and De Gi (Binh Dinh province) due to the impact of jettytypes” The article was published in Journal of Marine Stience and Technology inOctober 2010, No 2, pages of 0113 The contents of the article supplied someinformation of present condition and impact for sedimentation of protectiveembankments at the estuaries of Sa Huynh, Tam Quan and De Gi via the field surveydata The study result showed that the sediment impacts of the jetties at these threeestuaries were the same, The longshore current which had the direction from the southto the north played a deci Wve role in the process of transportation and accumulation ofbed material caused the estuary sedimentation, and it converged enough natures of acoastal hydrodynamic structure The measure for constructing the jetties in front of

river mouth which barrier the South-North currents to prevent the estuary

sedimentation, in consideration of science, was a proper one However, this measure

led to some changes in the hydrodynamic regime at the estuary area, dragging theprocess of transporting up sediment materials from the south, in which there was alarge amount which deposited at the front surface of the jetty and another significant‘amount was put into for depositing the estuary and channel, Particularly, at Tam Quan

estuary, constructing lasted the jetty to about 850 m, at that time there was not

anything to guarantee the effect on preventing the -dimentation, but thestuary $

hydrodyna mic regime showed the opposite.

‘Trinh Viet An (2012) had a study topic for the issue of some estuaries into fishingports and storm shelter areas for fishing ships in the Central which were beingseriously deposited, causing the significant impact to activities of fishery exploitation,activities of fishing logistic business, fisherman's life and political security of locality.‘This study showed obviously that the sedimentation phenomenon and concerned issuescould be very obviously sen at some typical river estuaries such as Tam Quan (BìnhDinh province), My A and Sa Huynh (Quang Ngai province), Da Rang (Phu Yen

province), Tung (Quang Tri province) and a series of the other Central Vietnam.

estuaries such as Dong Hai, La Gi, Phan Thiet, Nhat Le, ete This study gave thepreliminary comments of the major elements and the causes for the estuarysedimentation, as well as some existences of the constructed coastal trainingstructures, on this base the author petitioned some trends for solution Whereby, the‘concrete study results to Tam Quan estuary as follows:

~The phenomenon of the port entrance which was frequently seriously deposited

making the boats and ships easily {0 be thrown into the jetty and broken by big‘waves, making the boats and ships not dare to go into the port and theanchorage area Despite many structural measures with the big expense, thisphenomenon has not been overcome A temporary solution that was appliedwas frequent dredging the channel.

~The basic causes and elements for cai ăng sedimentation at Tam Quan estuaryin particularly as well as the Central Vietnam estuaries in generally include: (i)

the wave and longshore current due to the wave, (i) the tidal regime, and (ii)

the situation of typhoons and floods.

~ Analyzing and giving the comments on arranging the coastal raining structuresat Tam Quan estuary has not been proper

In 2015, Do Minh Duc implemented the topic “Study on scientific and technologicalsolutions to improve sedimentation phenomenon at estuaries where go in and outstorm shelter areas for boats and ships - applied for Tam Quan estuary, Binh Dinhprovince”, The study took out the basic causes and factors for causing Sedimentation atthe Central Vietnam estuaries; evaluated the present conditions and the causes ofsedimentation at Tam Quan estuary under the viewpoint of geology, geomorphologyand sediment, and under the viewpoint of the hydro-fossil dynami and gave thesolutions to prevent the sedimentation at Tam Quan estuary Whereby, the Mike 21‘model was applied to calculate the wave fields, the current fields, the water levels andthe morphological changes under the scenarios of without the jetty, within the 450 mjetty and within the 850 m jetty The results took out five main causes for causing the‘morphological changes at Tam Quan estuary including: (i) asymmetrical shape of theestuary topography, (i) the wave field with prevailing direction was the northeasterndirection; (ii) the wave refraction picture was rather uniform at the estuary despitefollowing the various wave directions; (iv) part of river discharge was stopped at theupstream reservoirs and (v) the jetty construction was improper The solutions wereproposed on the base of ensuring the channel normality to serve the flood drainage andwaterway traffic and to be suitable for the local economic condition, including 2groups: the first is to dredge and maintain periodically the channel routes; the second

is to arrange the works to prevent sands from both two sides (in which, the northern

side is dominant because the longshore current has a trend of going from the north tothe south), and to direct the flow and push the longshore current from the north away’The distance between the two heads of works took the waterway traffic requirementsand flood drainage at the estuary area

2.4.2 General information on the exi 1g Tam Quan fishing port

This ‘one of the ancient fishing ports in the north of the province The port was

spontaneously formed along Thien Chanh, Tan Thanh fishing villages of Tam Quan

Bac commune Tam Quan port is an advantage of wide estuary with anchorage water

about 70 ha and a channel to go in and out the port with the width of 1002140 m, thedepth of 2525.0 m, This isthe local port as well asthe storm shelters for fishing ships‘of coastal communes’ fisherpersons of Hoai Nhon district, one part in the north of PhuMy district and the vicinity

According to the current planning for sea port system to develop the Vietnam sea port,

‘Tam Quan port is one of the satellite ports of Quy Nhon port (including ports of Tam

Quan, De Gi and Dong Da), However, due to @ narrow and small channel, usuallydeposited, not meeting any requirements for any shipping ships which go in and out

the port, Binh Dinh province people’s committee has advocated to postpone investing

fon the sea port at Tam Quan commune and transferred the land area of 4.4 ha at‘Truong Xuan Tay hamlet into an iron hull ship building area Hence, in Tam Quanport area, it only remains function of a fish port and a storm shelter for fishing ships.Because Tam Quan channel gate is usually deposited, it is not enough depth for anyships with big capacity to go in and out the port, The anchorage waters are alsodeposited, invaded and the dredges are annually conducted with the volume of

50,000 100,000 m” without any effects; after the dredges, the sedimentation condition

still happens (Duc et al., 2015), Whereas, any fishing ships in the offshore increasinglyhhave bigger capacity and size so there are many difficulties and without being ensuredfor safety when going in and out Tam Quan estuary, Annually, there are 10215 shipsof accidents with many damages of people and property for the fishermen,

‘The management of ports and harbors also has many shortcomings; nowadays, anyships or boats which go in and out the port only declare with the inspective station ofthe Border post, then they can arbitrarily anchor in the port leading to the messy state,easily causing crash and loss of property Checking food safe hygiene has not beencarried out, the waste water and rubbish without being treated from the ships and thelogistic service foundations are all dumped directly into the river, which causes theenvironmental pollution and spreads diseases.

The task of residential plan and arrangement has not also concemed Nowadays, alongboth banks of Tam Quan river, on the hills, bars in the port area, there are residentswho are residing Especially, along the eastern area from the Border post to Thien“Chanh bridge (belong to the residents of Thien Chanh 1, 2 hamlets) gather erowdedlywith high density Many houscholds who lie close to the river banks arbitrarilyextending, placing soil and stones to invade the river bed, building bridges, temporarypiers to sell and buy fishes and to do business of materials, fuels, ice water, whichcauses environmental pollution, spreads diseases, without ensuring any safety for fireand explosion prevention,

In the years 200022002, with the investment from the Central, the port was

constructed newly for the work items: the southem jetty with the length of 450 m and

dredging the channel for ships to go in and out the port Until the years 2005=2007, itcontinued being invested on spreading the jetty for 400 m, dredging the jetty and stormshelters for fishing ships with the width of 56 ha with 5 anchorage pillars connectedwith land and 114 independent anchorage pillars which lied scattered along Tam Quanriver from Thien Chanh bridge to the channel gate, At the same time, the district alsoinvested in building to upgrade the wharf and Thien Chanh fish market, Tan Thanh 2fishery processing zone with the width of 1.4 ha and Thien Chanh 1 logis vice

zone infrastructure with the scale of 6.2 ha, Parallel with the State's investment, at