HYDRAULIC STUDY OF THE HYDRAULIC STUDY OF THE NERETVA RIVERNERETVA RIVER

• B.Sc.B.Sc. Draženka Kvesić, civ.Draženka Kvesić, civ. eng.eng., PRONING DHI, PRONING DHI

• M.M.SSc.c. Božidar Deduš, civ.Božidar Deduš, civ. eng.eng., PRONING DHI, PRONING DHI

22ndnd MIKE by DHI ConferenceMIKE by DHI Conference for Europe for Europe

13-15. October 2008.13-15. October 2008.

Dubrovnik, Dubrovnik, CroatiaCroatia

• NERETVANERETVA is one of the larger rivers in is one of the larger rivers in BHBH

• 225 km long225 km long;; and runs with its longest part through BH and runs with its longest part through BH (203 km), and 22 km through Croatia(203 km), and 22 km through Croatia

• unique ecological systemunique ecological system

• several hydroelectric power plantsseveral hydroelectric power plants

• 9 t9 tributaries ributaries

• emerald- green, clean and entirely drinkableemerald- green, clean and entirely drinkable

• The Neretva river flows into the Adriatic Sea in the vicinity The Neretva river flows into the Adriatic Sea in the vicinity of Opuzen within the Neretva deltaof Opuzen within the Neretva delta

STARI STARI MOSTMOST

MOSTARMOSTAR

POČITELJPOČITELJ

DELTADELTA

• 50 km section50 km sectionfrom from hydroelectric power plant HE hydroelectric power plant HE MMOSTAROSTAR to to METKOVIĆMETKOVIĆ

Three parts of project:Three parts of project:

• hydrological analyses, hydrological analyses,

• hydraulic calculationhydraulic calculation,,

• mapping of flooding zones. mapping of flooding zones.

1-D model1-D model >>>> MIKE 11MIKE 11

HYDROLOGICAL ANALYSESHYDROLOGICAL ANALYSES

• creating historical and current FLOW creating historical and current FLOW CURVES Q(H)CURVES Q(H)

• defining adjacent CORRELATIONS of defining adjacent CORRELATIONS of water levels and flowwater levels and flow

• defining WATER BALANCESdefining WATER BALANCES

• Calculating of PROBABILITIES on Calculating of PROBABILITIES on HIGH WATER OCCURRENCESHIGH WATER OCCURRENCES

Synoptic survey of calculated hydrologicalSynoptic survey of calculated hydrological parameters which are presented in this parameters which are presented in this project:project:

Cartographic survey of the respective catchments Cartographic survey of the respective catchments of the Neretva river with hydrological stations :of the Neretva river with hydrological stations :

Discharge of various recurrent periods: 20,100 and 500 years

HYDRHYDRAULIC CALCULATIONS AULIC CALCULATIONS and ANALYSIS OF RESULTSand ANALYSIS OF RESULTS

1.1. MATHEMATICAL MODELMATHEMATICAL MODEL

GGeometric models :eometric models :

• HE Mostar – VS Gabela,HE Mostar – VS Gabela,

• HE Mostar – VS Dračevo,HE Mostar – VS Dračevo,

• HE Mostar – VS Metković,HE Mostar – VS Metković,

• VS Žitomislići - VS Dračevo.VS Žitomislići - VS Dračevo.

TThe cross sections models :he cross sections models :

• Model 1984Model 1984,,

• Model 1997Model 1997,,

• Model 2003/05Model 2003/05..

TThe changes of cross section profile he changes of cross section profile “32+487” “32+487” throughout the yearthroughout the yearss

• The UPSTREAM boundary conditions The UPSTREAM boundary conditions are defined at all entries into the are defined at all entries into the mathematical model, mathematical model, andand Q(t) is Q(t) is used.used.

• The DOWNSTREAM boundary The DOWNSTREAM boundary condition as the water level diagram condition as the water level diagram h(t), is used as boundary condition. h(t), is used as boundary condition.

2.2. BOUNDARY CONDITIONSBOUNDARY CONDITIONS

3. 3. CALIBRATION AND VERIFICATION OF CALIBRATION AND VERIFICATION OF THE MATHEMATICAL MODEL OF THE THE MATHEMATICAL MODEL OF THE NERETVA RIVERNERETVA RIVER

• uunsteady flow nsteady flow

• water levelwater level

• 7 hydrological stations on Neretva +7 hydrological stations on Neretva +7 hydrological stations on Neretva’s 7 hydrological stations on Neretva’s tributaries tributaries

• 7 historical events, from 1995.-2005.7 historical events, from 1995.-2005.

EEvents for which the vents for which the calibrationcalibration of the model has been conducted of the model has been conducted::

EEvent for which the vent for which the verificationverification of the model has been of the model has been conductedconducted::

RResult of the calibration of unsteady esult of the calibration of unsteady flow, for locationflow, for location VS Bačevići:VS Bačevići:

ManningManning

4. 4. HYDRAULIC CALCULATION FOR HYDRAULIC CALCULATION FOR STEADYSTEADY FLOWFLOW,, FOR RANK 1/20, 1/100 AND 1/500 YFOR RANK 1/20, 1/100 AND 1/500 YEARSEARS

TTwo different scenarios:wo different scenarios:

• with embankments (which is the real case)with embankments (which is the real case),,

• without embankmentswithout embankments..

RRecurrent periodecurrent periods:s:

• 20,20,

• 100 and100 and

• 500 years500 years..

Longitudinal section with marked maxLongitudinal section with marked max.. water level for RP=100water level for RP=100 yearsyears

5. 5. ANALYSIS OF THE CHANGES IN THE ANALYSIS OF THE CHANGES IN THE FLOW REGIME IN ORDER TO EVALUATE FLOW REGIME IN ORDER TO EVALUATE THE ANTHROPOGENIC INFLUENCE DUE THE ANTHROPOGENIC INFLUENCE DUE TO GRAVEL EXPLOITATION ALONG THE TO GRAVEL EXPLOITATION ALONG THE SECTION FROM THE BORDER TO SECTION FROM THE BORDER TO ČAPLJINAČAPLJINA

• Cross section profiles from three Cross section profiles from three different time periodsdifferent time periods: 1984., 1997. and : 1984., 1997. and 2005.2005.

• Gravel exploatationGravel exploatation

• 15 km section15 km section

• AAt chainage 33 km t chainage 33 km -- the water surface level shifts. the water surface level shifts.• RRiver bed is becoming deeper downstream of that iver bed is becoming deeper downstream of that

chainagechainage..• Upstream of the 33 km at the Neretva riverUpstream of the 33 km at the Neretva river,,

water level has a tendency of rising. water level has a tendency of rising.

MAPPING FLOODSMAPPING FLOODS

• the cartographic layout of hydraulic the cartographic layout of hydraulic simulation results simulation results

• orthophoto maps orthophoto maps

• 3D Digital Elevation Model (DEM) 3D Digital Elevation Model (DEM)

• recurrent periods 20, 100 and 500 recurrent periods 20, 100 and 500 yearsyears

70 maps 70 maps 60/90 cm:60/90 cm:

- - existing bankexisting bank protections protections

- a- andnd withoutwithout them them