low flow management in wallonia • philippe...

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Low flow management in Wallonia

ir Philippe Dierickx NHV, Maastricht, 24 october 2014

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Introduction

Water uses and drought impacts

Complex low flow management examples

State of art in Wallonia :

Observations

Forecastings

Real-time management

Summary

Wallonia

Flanders

Bxl

Netherlands

France

Lux

Germ

an

y

Meuse (Maas): 12.355 km²

Escaut (Schelde): 3.774 km²

Rhine : 767 km²

Seine : 40 km²

TOTAL: 16.936 km²

~18.000 km of rivers

River basins of Wallonia

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Wallonia has a complex and intensive use of its water ressources for :

Inland navigation

Drinkable water

Hydraulic power production

Thermic and nuclear power plants cooling

Agriculture

Tourism

More critical because :

Needs are growing

Environment rules are more important (fish migration, water quality…)

Impact of global warming scenarios

Economic issues

low flow management is necessary to aim different and sometimes conflicting goals !

Water uses on the walloon river network

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Wallonia has a typical north-west continental climate with, usually:

stratiform rainfalls or snow events filling underground and reservoirs in winter

convective events with heavy rainfalls in summer

droughts are mainly observed during fall in september and october

variable: droughts are sometimes observing during spring or at the beginning of winter

What’s a drought for Wallonia ?

there is no legal definition, as statistics or threshold

some local definitions exist but for only specific purposes as intakes / oulets

a situation for which one some actions must be done to limit the consumption of water

Droughts in Wallonia

450 km of navigable waterways

60 % of controled rivers

40 % of canals

Navigation

From 300 to 9.000 T ships

• 40 weirs on controled rivers

• 80 locks

water consumption

water regulation

Weirs and locks Navigation

New locks 2015

New lock 2017

New locks 2025

Navigation

Drought impacts on navigation

Resizing of locks will increase the water consumption

Resizing of locks should increase the navigation

Navigation will be more sensitive to droughts (even without climate changes)

Difficulties to maintain water levels for full loaded ships

More waiting time at locks to reduce consumption (ships gathering)

Economic impacts

Projects:

Improve the regulation of water to mitigate loss of water

Optimize water supplies through reservoirs

Reduce the leaks at locks

Optimize the traffic management

Use pumping station with cost optimization

Upper Maas

1 power plant

+ 3 projects

Maas

6 power plants

Sambre

3 power plants

+ 3 projects

Hydraulic power plants on navigable waterways

EDF-Luminus

Energie Fleuves

Muyle

Projects

Mérytherm

Albert Canal

1 under constr.

Hydraulic power plants

Hun Marcinelle

Monsin

Total: ~80 MW

Droughts decrease power production of sustainable energy

Thermic and nuclear plants cooling

Tihange: 3.000 MW

Drought means slow velocities and less dissipation of hot water returned by plants

production could be limited (especially during hot weather conditions)

economical impacts are quite important

Reservoirs • 9 reservoirs: 5 public, 4 private

Reservoirs

• Navigation support

• Drinkable water

• Flood control

• Power production

• Tourism

La Gileppe

Eau d’Heure reservoirs

Eupen

Nisramont

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Reservoirs

Eau d’Heure volumes

Theoretical capacity Effective capacity

Water supply for

navigation

After the 2003 drought, almost 3 years were

necessary to get back to full capacity

10.106 m³

Drinkable water

Groundwater

Surface water

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Drinkable water

During extreme droughts, some practices

could be forbidden to avoid waste of water

but hard to control

Tourism

Some reservoirs are recreational areas:

supply water for navigation during summer is conflicting

Some rivers are famous for kayak

lovers but activities are stopped

during droughts due to

environmental troubles

Small waterways are

maintained for

tourism navigation

Fish migration

Fish passes require water consumption

Nowadays, reserved discharges are enforced to maintain enough water above weirs to

reduce fish mortality through power plant or to keep enough water downstream

reservoirs

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Charleroi-Brussels Canal

The canal ensures the link between the Maas Basin and the Schelde basin

from south to north (Flanders and Brussels) and west (Liège) to east

(Tournai through Center Canal)

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Water supply &

power

Navigation & fish migration

Natural flow

Pumpings

Natural flow

Natural flow

Highly complex water management for :

Navigation

Environmental issues

Costs

Benefits

Tourism

request hydrologic, hydraulic and economic models !


Lower Maas Monsin

Netherlands

Common M. Lixhe

Albert Canal Lanaye

Genk

Navigable Maas

Wallonia

Flanders

Flanders

Jeker

Liège

Maas downstream Liège (Luik)

Q Liège > 60 m³/s Waterlevel of 60 m DNG to keep

permanently on a 60 km reach

Lower Maas Monsin

Netherlands

Common M. Lixhe

Albert Canal

Lanaye

Genk

Navigable Maas

Lock

Monsin

Lock

Visé

Diverse

Flows

Borgharen Non navig.

Maas

Juliana

Canal

Zuid

Willems

vaart

Wallonia

Flanders

Flanders

Berwinne

Fishways

Jeker

Liège


Q Liège < 60 m³/s


Year 2011: several low water events

7 months

During droughts, the Canal consumption could be close to

the discharges in Liège

Normal waterlevel for navigation: 60 m

59 m


Year 2011: several low water events

1 m


In 2015: new lock (L225 x W25 x H14) in Lanaye with a pumping station and turbines

Permit (fish migration) :

• obligation of pumping if Q Lixhe < 50 m³/s

• turbines allowed if Q Liège > 120 m³/s

Challenge: how to keep water levels during droughts ?

different outlets : locks of Lanaye, Genk, Monsin dam & power plant

different managers : Wallonia (SPW), Flanders (Scheepvaart), Private company (EDF-Luminus)

keep enough water downstream

respect environmental permits

optimize benefits / costs

improvment of hydrologic knowledge

simulation models (hydraulic & economic)

agreement between partners

real-time management


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Today on the walloon hydrologic network

• main observed consequences of droughts are related to navigation

• just enough water to avoid problems for drinkable water and refreshment of

industries

• BUT we never had to face up to 2 consecutive years with low water

the phreatic aquifer was always reloaded

close to the limits

• the probability of this « worst case scenario » is raising due to growing needs and

climate change

• politicians and inhabitants are not enough concerned by water scarcity

• however, some actions are on the way…

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Observations

A good measurement is ALWAYS better

than an excellent calculation or estimation !

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Rainfall network and weather radars

RMI

Wacondah network

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Wacondah network

140 stations on navigable waterways and tributaries.

5’ step (GPRS)

Water level network

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Aqualim network

180 stations on non navigable waterways

Water level network

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Discharges measurement by rating curves

Propeller

ADCP

Increasing of measurement during

low water as rating curves are more

sensitive to :

- cross sections changes

- grass inside the river

- artificial perturbations

Accuracy must be improved

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Haccourt Visé

Amay

Waulsort

Ronet

Tournai Solre

Châtelet

Tailfer (2015)

Marchienne

Lessines

Huy

Monceau

Clabecq (2015)

Discharges measurement by ADM

Best solution for flow measurement

on navigable waterways

Clomines (2016)

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Piez’eau network

400 stations including 150 in real-time

Groundwater network

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Weir sensors

Accuracy is important for flow

management

Weir sensors calibration

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For instance, we have to keep 20 cm

above some weirs on the Maas river

for fish migration

Leaks estimation

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On field measurement

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Database and series

Requirements:

telemetry : mainly GPRS or optical fibers

efficient quality control

automatic

manual

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Drought forecasting

Weather models

Ensemble predictions

NWP

Hydrologic observations

+

Stochastic models

Potential / effective evapotranspiration

(LSA SAF)

+

Not accurate !!!

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Qr (t,x)

Zr (t,x)

Y

X

Qb (t) Qin (t)

PLC Zamont (t)

Phausse (t)

Ovanne (t)

Qc (t)

PLC

Zc (t) Qmesuré (t)

Z* = Consigne

Development of simulation models for water management

Water levels AND discharges

regulation

With economical issues

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Water level regulation could be… very bad

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Mesure de niveau

amont Interface ISN-02

Module de filtrage

AE-95

AFFICHAGE

18 bits

4x4 BCD

1 Valid.

1 Déft4 - 20 mA

Cap

teur

Lig

ne

Inte

rfac

e

Conta

cts

Tendances

Hauteur

(cote état-major)

Communication

RS232 ou RS485

Vers relayage

des organnes de

commandeAFFICHAGE 0 3

0 3

>

<

=

1 5

1 8

>

<

=Roues codeuses BCD

Hauteur

filtrée

1 5 1 8

BCD

Communication

RS232 ou RS485

Roues codeuses

Module de temporisation

et de commande des relais

AE-96

Hauteur de

référence

Comparateurs à

fourchette

2 x CSP 17/005

Délai

Hydrologic observations

database

Structure monitoring database

Automatic local

management

Structure commands

Optimization of local flows including global informations

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Progression…

time to think about water scarcity !!!

CONTACT

Service public de Wallonie

Direction générale opérationnelle Mobilité et Voies hydrauliques

Boulevard du Nord, 8

B-5000 NAMUR

BELGIQUE

Tél: + 32 81 77 29 83

Fax: + 32 81 77 37 88

[email protected]

Thank you

low flow management in wallonia • philippe...

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