WP03: ANALYTICAL TOOLS, MODELS

WP03: ANALYTICAL TOOLS, MODELS

TELEMAC MODELLING PROGRESS

WP03: ANALATICOL TOOLS, MODELS

PLANPLAN

Characteristics of the studied areaCharacteristics of the studied area

Water quality issuesWater quality issues

Data descriptionData descriptionModel constructionModel construction

ScenariosScenarios simulatedsimulated

Results discussionResults discussion

constructionconstruction of the second model of the second model


The coastline of Hammamet contains 12 little oueds draining small watersheds which have no have no influence on hydrodynamism of Gulf Hammamet

This region is sheltered from the general Mediterranian currents (N-S) (N-S) thanks to the Cap Bon “peninsula”.

The tide in the gulf of Hammamet is semi-diurnal and has slight amplitude (20 cm). it has no influence on hydrodynamism

the most important factor that affects the hydrodynamism in the region is the wind

Characteristics of the studied areaCharacteristics of the studied area


Water quality issuesWater quality issues

Our case study simulates the Our case study simulates the impact of a recycled water impact of a recycled water discharge (from the station discharge (from the station STEP3 STEP3 ) ) on the swimming water quality on the swimming water quality through an off-shore emissary. So, through an off-shore emissary. So, we do monitor the dispersion plume we do monitor the dispersion plume of COD and BOD coming from the of COD and BOD coming from the emissary that is 1600 m far from the emissary that is 1600 m far from the coast and laying at –23m depth.coast and laying at –23m depth.

The objective of this stady is to The objective of this stady is to know how polluants are disperced know how polluants are disperced in the gulf of Hammamet ( plume in the gulf of Hammamet ( plume extend, affected zones);extend, affected zones);

Even if the rejections are conform Even if the rejections are conform to national standards this exercice to national standards this exercice will allow us to implement an early will allow us to implement an early warning system and action plan in warning system and action plan in the case of break down of treatment the case of break down of treatment station or over flow;station or over flow;

Sustainable management of STEP3 Sustainable management of STEP3 can be released from this study.can be released from this study.

We note that Hammamet is a very important region for the seaside tourism. In such context We note that Hammamet is a very important region for the seaside tourism. In such context we must be vigilant and able to face any possibility of marine contamination.we must be vigilant and able to face any possibility of marine contamination.


Bathymetry extracted from topographic map (1/25000)

Data descriptionsData descriptions


DEM generated by MATISS and plotted with RUBENS


Flow variation of the water treatment station (STEP3)

66

48

38

23

60

84

102

108112

115

117

120124

127 128

125 120

11198

84

19

2223

35

60

0

20

40

60

80

100

120

140

06:00:00

07:00:00

08:00:00

09:00:00

10:00:00

11:00:00

12:00:00

13:00:00

14:00:00

15:00:00

16:00:00

17:00:00

18:00:00

19:00:00

20:00:00

21:0

0:00

22:00:00

23:00:00

00:00:00

01:0

0:00

02:00:00

03:00:00

04:00:00

05:00:00

06:00:00

07:00:00

08:00:00

09:00:00

10:00:00

Q

(l/s)


174

11

30

154

7

30

164

15

30 30

268

7

30

179

19

30

174

21

30

160

20

30

196

17

30

314

1430

111

15

30

120

6

30

183,09

13,8

1 30

0

50

100

150

200

250

300

350

mg

O2/

l

janv

-03

févr

-03

mar

s-03

avr-

03

mai

-03

juin

-03

juil-

03

août

-03

sept

-03

oct-

03

nov-

03

déc-

03

Moy month

Variation of DBO5

DBO5 input (mg/l)

DBO5 output (mg/l)

NS

Data descriptionData description

492

8890

430

8290

245

7290 90

911

7290

672

7890

42811

0

90

623

101

90

743

9090

1331

100

90

277

6090

342

74

90

590,36

84,2

7

90

0

200

400

600

800

1000

1200

1400

mg

O2/l

janv

-03

févr

-03

mar

s-03

avr-

03

mai

-03

juin

-03

juil-

03

août

-03

sept

-03

oct-

03

nov-

03

déc-

03

Moy

month

Variation of DCO

DCO input (mg/l)

DCO output(mg/l)

TS



Model constructionModel construction 19804 meshes 10090 nodes

Modelling domain

Boundary conditionSolid limit (2222)

Boundary conditionimposed Level (5445): 0 m

Two kinds of boundary conditionsTwo kinds of boundary conditions

Model constructionModel construction



315°(20 m/s)

90°(26 m/s)

ScenariosScenarios simulated simulated TELEMAC2DTELEMAC2D


ScenariosScenarios simulated simulated SUBIEF2DSUBIEF2D

The hydrodynamic model needs more accurate data and The hydrodynamic model needs more accurate data and adjustement to restitute faithfully the realityadjustement to restitute faithfully the reality

We did revew input data and parameters:We did revew input data and parameters: Acquisition of detailed wind series dataAcquisition of detailed wind series data Acquisition of more pricise bathymetric dataAcquisition of more pricise bathymetric data Model extendModel extend Conception of new meshesConception of new meshes Reconsideration of the boundary conditions Reconsideration of the boundary conditions Acquisition of boundary conditions value (velocity) fram a model implemented overall tunisian coastal line ( INSTM research group)Acquisition of boundary conditions value (velocity) fram a model implemented overall tunisian coastal line ( INSTM research group)

Results discussionResults discussion

Construction of new modelConstruction of new model



Construction of the second modelConstruction of the second model

Integration of more Integration of more detailed bathymetry and detailed bathymetry and new modelling domainenew modelling domaine

bathymetry plotted on bathymetry plotted on RUBENSRUBENS


elements Number :elements Number :

1510615106

Number of nodes :Number of nodes :

78747874

Length Length max :Length Length max :

1461m1461m

min :min :

1m1m

Meshe parametres parametresConstruction of the second modelConstruction of the second model


Construction of the second modelConstruction of the second model


Boundary Boundary conditionsconditionsConstruction of the second modelConstruction of the second model

Documents

WP03: ANALYTICAL TOOLS, MODELS