restoration measures at Austrian-Slovakian border section of river Morava: concepts, experience and outlokk.

1. Restoration measures at
Austrian-Slovakian border
section of Morava river
Presentation at RESTORE - Workshop
10th May 2012,
Iasi, Romania
DI Albert Schwingshandl
riocom – Consulting Engineers
Siebensterngasse 31/2, A-1070 Wien. www.riocom.at

2. CONTENT
1. Introduction to the area
2. History of river training works at Morava river.
3. Development of fluvial morphology.
4. Sediment processes.
5. Effects on flooding processes.
6. Restoration measures.
7. Monitoring results.

3. 1. Introduction to the area
2. History of river training works at Morava river.
3. Development of fluvial morphology.
4. Sediment processes.
5. Effects on flooding processes.
6. Restoration measures.
7. Monitoring results.

4. INTRODUCTION TO THE AREA
Morava river has its
source in North-East of
Czech Republic at
1.275 m a.s.l.

5. Introduction to the area
GEOGRAPHIC SITUATION
Morava river has its
source in North-East of
Chech Republic at
1.275 m a.s.l.
at its lower reach it
forms the border
between Austria and
Slovakia at a length of
70 kilometres
(136 m a.s.l.)

6. Introduction to the area
HYDROLOGICAL-HYDRAULIC
CHARACTERIZATION
flood (100 years return period)
HQ100 1.400 m³/s
mean annual flood discharge
HQ1 440 m³/s
bankfull discharge
265 m³/s
mean water
MQ 115 m³/s
low water
NQ 33 m³/s
• discharge maximum in spring,
minimum in autumn.
• nivo-pluvial discharge regime.

7. Introduction to the area
HYDROLOGICAL-HYDRAULIC
CHARACTERIZATION
channel width 40 – 200 m,
mean width 70 m
mean slope 0,18 ‰
water depth (measured
from MQ level) 2 – 6 m
velocity at MQ 0,8 m/s

8. Introduction to the area
RIVER MORPHOLOGICAL
CHARACTERISTICS
initially meandering river course
initial bed slope 0,12 ‰
before river training
(aereal picture 1942 )

9. 1. Introduction to the area
2. History of river training works at Morava
river.
3. Development of fluvial morphology.
4. Sediment processes.
5. Effects on flooding processes.
6. Restoration measures.
7. Monitoring results.

10. HISTORY OF RIVER TRAINING
WORKS
Objectives of river training works:
Improvement of land use.
Reduction of high probability flooding.
Improvement of conditions for navigation.
After 1918: Border definition between CSSR and
AT.
Main phases of construction works:
1. phase 1911 to 1918: river mouth longitudinal
structures March km 0-4,7.
With the foundation Joint 2. phase 1919 to 1934: AT until 1925 wooden
Technical Commission in structures for river bank protection; partial
1931 Morava river training
works got a new bilateral excavation of cut-offs.
administrative basis
3. phase 1935 to 1967: Revision of „General
Project 1935“ -> detail projects (meander cut-
offs, standard cross section .

11. History of river training works
Example TRAINING WORKS
MORAVA Cut-Off V
Upper core of
Cut-off V.
Source:
Archiv der ehemalg. Marchbauleitung des
Bundesstrombauamtes im
Bundesministerium für Verkehr, Innovation
und Technologie, Abteilung IV/W3.
Digitale Reproduktion:
DI Gerald Benz
Photografische Bearbeitung:
Mag. Elisabeth Beer

12. History of river training works
Example TRAINING WORKS
MORAVA Cut-Off V
Opening of the upper core of
Cut-off V.
Quelle:
Archiv der ehemalg. Marchbauleitung des
Bundesstrombauamtes im
Bundesministerium für Verkehr, Innovation
und Technologie, Abteilung IV/W3.
Digitale Reproduktion:
DI Gerald Benz
Photografische Bearbeitung:
Mag. Elisabeth Beer

13. History of river training works
Example TRAINING WORKS
MORAVA Cut-Off V
Quelle:
Archiv der ehemalg. Marchbauleitung des
Bundesstrombauamtes im
Bundesministerium für Verkehr, Innovation
und Technologie, Abteilung IV/W3.
Digitale Reproduktion:
DI Gerald Benz
Photografische Bearbeitung:
Mag. Elisabeth Beer

14. 1942 RESULTS OF
RIVER TRAINING WORKS
Source:
BEV 1941-42.
Bearbeitung:
riocom, A. Schwingshandl

15. Regulierungsgeschichte RESULTS OF
1995
RIVER TRAINING WORKS
Results:
The river training which has been
implemented in past century has changed
the fluvial morphology of Morava river
sistematically and substantially,
regarding layout, longitudinal profile and
cross section geometry.
Kex data:
17 cut-offs were built, the river course was
shortened by 11 kilometres.
About 70% of the river banks are
stabilized by engineering structures.
Standardization of the channel geometry
and increase of the discharge capacity of
the standard cross section, consequently
decrease of lateral connectivity.
Source:
BEV

16. History of river training works RESULTS OF
RIVER TRAINING WORKS
Meander XVIa.

17. History of river training works RESULTS OF
RIVER TRAINING WORKS
Cut-off section IV
(concave bank already with
restoration measures).

18. History of river training works RESULTS OF
RIVER TRAINING WORKS
Still, high potential
for restoration, due
to partly low
intensity of uses
most important
lowland river
ecosystem in
Austria
Meadow near Marchegg

19. Introduction to the area
RIVER RESTORATION
PLANNING PROCESS
1994 RAMSAR concept
1995-97 MARTHA95 river development scheme
1999-2002 LIFE pilot restoration project MUF
2003-2005 MUF monitoring
2004-2006 BGM Bilateral General Project
2011-2013 LIFE project, MORE (ETZ)

20. 1. Introduction to the area
2. History of river training works at Morava river.
3. Development of fluvial morphology.
4. Sediment processes.
5. Effects on flooding processes.
6. Restoration measures.
7. Monitoring results.

21. Development of fluvial morphology
CROSS SECTION GEOMETRY
7,0
Profilgeometrie vor Regulierung
6,5
Situation before river
training shows a 6,0
wide range of cross 5,5
section geometry.
Mittlere Profiltiefe [m] 5,0
4,5
4,0
3,5
3,0 B = 72 -83 m, T = 3,1 bis 3,6 m
2,5
B = 64 -99 m, T = 1,9 bis 2,7 m
2,0
1,5
B = 84 -112 m, T = 1,5 bis 1,9 m
Quelle:
1,0
Erstellung von wasserwirtschaftlichen
Planungsgrundlagen für die Ö-SK 0,5
Marchgrenzstrecke.
riocom, G. Benz, A. Schwingshandl0,0
Im Auftrag:
via donau – Österr. Wasserstraßen- 0 20 40 60 80 100 120 140
Gesellschaft mbH. Bordkantenentfernung [m]

22. Development of fluvial morphology
CROSS SECTION GEOMETRY
7,0
Profilgeometrie vor Regulierung
6,5
Situation before river Profilgeometrie nach Regulierung
training shows a 6,0
wide range of cross 5,5
section geometry.
Mittlere Profiltiefe [m] 5,0
By training measures 4,5
a standardized profile 4,0
B = 60 – 80 m, T = 2,8 -3,8 m
was put in place.
3,5
3,0 B = 72 -83 m, T = 3,1 bis 3,6 m
2,5
B = 64 -99 m, T = 1,9 bis 2,7 m
2,0
1,5
B = 84 -112 m, T = 1,5 bis 1,9 m
1,0
0,5
0,0
0 20 40 60 80 100 120 140
Bordkantenentfernung [m]

23. Development of fluvial morphology
STANDARDIZATION OF CHANNEL
GEOMETRIE
This standardizing of the
channel geometry also
means, that over long
sections a bank levee was
constructed.
This levee mostly is higher
than the sourrounding flood
plain and therefore builds a
barrier for frequent
inundation. Moravka
Zaya

24. Development of fluvial morphology
DEVELOPMENT OF RIVER BED
ELEVATION
150
Mean river bed elevation
149
148 Sohlhöhe 1908
147
146
145
144
143
Sohlhöhe [m.ü.A.]
142
141
140
139
138
137
136
Thaya Hohenau
135
134
Baumgarten
Weidenbach
D XVI - XVIII
Marchegg
133 Dürnkrut
D III - VII
D IX - XII
Angern
Malina
132
D XIV
Zaya
D XIII
D XV
D II
131
130
70.000 60.000 50.000 40.000 30.000 20.000 10.000 0
Stationierung [m]

25. Development of fluvial morphology
DEVELOPMENT OF RIVER BED
ELEVATION
150
Mittlere Sohlhöhen
149
148 Sohlhöhe 1908
147 Sohlhöhe 1934
146
145
144
143
Sohlhöhe [m.ü.A.]
142
141
140
139
138
137
136
Thaya Hohenau
135
134
Baumgarten
Weidenbach
D XVI - XVIII
Marchegg
133 Dürnkrut
D III - VII
D IX - XII
Angern
Malina
132
D XIV
Zaya
D XIII
D XV
D II
131
130
70.000 60.000 50.000 40.000 30.000 20.000 10.000 0
Stationierung [m]

26. Development of fluvial morphology
DEVELOPMENT OF RIVER BED
ELEVATION
150
Mittlere Sohlhöhen
149
Sohlhöhe 1908
148 Sohlhöhe 1934
147 Sohlhöhe 1956/58
146
145
144
143
Sohlhöhe [m.ü.A.]
142
141
140
139
138
137
136
Thaya Hohenau
135
134
Baumgarten
Weidenbach
D XVI - XVIII
Marchegg
133 Dürnkrut
D III - VII
D IX - XII
Angern
Malina
132
D XIV
Zaya
D XIII
D XV
D II
131
130
70.000 60.000 50.000 40.000 30.000 20.000 10.000 0
Stationierung [m]

27. Development of fluvial morphology
DEVELOPMENT OF RIVER BED
ELEVATION
150
Mittlere Sohlhöhen
149 Sohlhöhe 1908
148 Sohlhöhe 1934
Sohlhöhe 1956/58
147
Sohlhöhe 1988/95
146
145
144
143
Sohlhöhe [m.ü.A.]
142
141
140
139
138
137
136
Thaya Hohenau
135
134
Baumgarten
Weidenbach
D XVI - XVIII
Marchegg
133 Dürnkrut
D III - VII
D IX - XII
Angern
Malina
132
D XIV
Zaya
D XIII
D XV
D II
131
130
70.000 60.000 50.000 40.000 30.000 20.000 10.000 0
Stationierung [m]

28. Development of fluvial morphology
DEVELOPMENT OF RIVER BED
ELEVATION
150
Mittlere Sohlhöhen
Sohlhöhe 1908
149
Sohlhöhe 1934
148 Sohlhöhe 1956/58
147 Sohlhöhe 1988/95
146 Sohlhöhe 2006
145
144
143
Sohlhöhe [m.ü.A.]
142
141
140
139
138
137
136
Thaya Hohenau
135
134
Baumgarten
Weidenbach
D XVI - XVIII
Marchegg
133 Dürnkrut
D III - VII
D IX - XII
Angern
Malina
132
D XIV
Zaya
D XIII
D XV
D II
131
130
70.000 60.000 50.000 40.000 30.000 20.000 10.000 0
Stationierung [m]

29. Development of fluvial morphology
DEVELOPMENT OF RIVER BED
ELEVATION
150
Mittlere Sohlhöhen
Sohlhöhe 1908
149
Sohlhöhe 1934
148 Sohlhöhe 1956/58
147 Sohlhöhe 1988/95
146 Sohlhöhe 2006
145
144
143
Sohlhöhe [m.ü.A.]
142
141
140
139
138
137
136
Thaya Hohenau
135
134
Baumgarten
Weidenbach
D XVI - XVIII
Marchegg
133 Dürnkrut
D III - VII
D IX - XII
Angern
Malina
132
D XIV
Zaya
D XIII
D XV
D II
131
130
70.000 60.000 50.000 40.000 30.000 20.000 10.000 0
Stationierung [m]

30. 1. Introduction to the area
2. History of river training works at Morava river.
3. Development of fluvial morphology.
4. Sediment processes.
5. Effects on flooding processes.
6. Restoration measures.
7. Monitoring results.

31. SEDIMENT PROCESSES

32. sediment processes
SUSPENDED SEDIMENT
MODELLING
The aim is to gain
knowledge on the
sedimentation processes in
the floodplains.
Results of long-term
modelling (31 years).
Source:
Num. 2D-Modell für March und Thaya in A,
SK und CZ.
ARGE riocom-IB Humer-Aquasoli
Im Auftrag:
via donau und Land NÖ-WA2

33. sediment processes
SUSPENDED SEDIMENT
MODELLING
Results of long term
modelling (31 years).
Section: Morava at
Zaya river mouth
Quelle:
Num. 2D-Modell für March und Thaya in A,
SK und CZ.
ARGE riocom-IB Humer-Aquasoli
Im Auftrag:
via donau und Land NÖ-WA2

34. sediment processes
MORPHOLOGICAL DYNAMICS:
EROSION - SEDIMENTATION
The digital terrain model
(laserscan 2007;
3d-Shade) how the balance
between sedimentation and
erosion is proceeding in a
dynamic river system:
by erosion on the concave
bank the river „consumes“ the
natural bank levee and
migrates,
and leaves behind a natural
bank levee on the convex
bank.
Grafik Quelle: Num. 2D-Modell für March und Thaya in A, SK und CZ.
ARGE riocom-IB Humer-Aquasoli. Im Auftrag: via donau und Land NÖ-WA2

35. Entwicklung der
Gewässermorphologie MORPHOLOGICAL
DEVELOPMENT
Due to morphological
changes the bankfull
discharge is exceeded less
frequently. Event 1: Morava river morphology was shifted into an
Discharges between NQ and new system stage by the river training works
HQ1 remain within the (singulary event).
bankfull cross section.
Process 1 River bed deepening: in lage sections of
Morava river the channel bed deepened significantly
Für das morphologische between the river training and ca. 1990
Gesamtsystem der March stellt (Continous process … +/- terminated).
sich in Hinblick auf die Zukunft
die essentielle Frage: Process 2: sedimentation along river bank, while river
kommt (u.a.) durch das layout is fixed, causes a successive raisening of river
Fortschreiten von Prozess 2 bank (Continous process … ongoing).
(Sedimentation) in einer
bestimmten Phase/Abschnitt
wieder Prozess 1
(Sohleintiefung)
in Gang ?

36. 1. Introduction to the area
2. History of river training works at Morava river.
3. Development of fluvial morphology.
4. Sediment processes.
5. Effects on flooding processes.
6. Restoration measures.
7. Monitoring results.

37. EFFECTS OF MORPHOLOGY
ON FLOODING PROCESSES
Quelle: Hydromonitoring für die Maßnahmen an der March
in Marchegg Km 15-25. riocom, A. Schwingshandl
Im Auftrag: Wasserstraßendirektion / via donau

38. EFFECTS OF MORPHOLOGY
ON FLOODING PROCESSES
Quelle:
Hydromonitoring für die Maßnahmen an der March in Marchegg
Km 15-25. riocom, A. Schwingshandl
Im Auftrag: Wasserstraßendirektion / via donau
Quelle: Hydromonitoring für die Maßnahmen an der March
in Marchegg Km 15-25. riocom, A. Schwingshandl
Im Auftrag: Wasserstraßendirektion / via donau

39. 1. Introduction to the area
2. History of river training works at Morava river.
3. Development of fluvial morphology.
4. Sediment processes.
5. Effects on flooding processes.
6. Restoration measures (-> pres.#2).
7. Monitoring results.

40. 1. Introduction to the area
2. History of river training works at Morava river.
3. Development of fluvial morphology.
4. Sediment processes.
5. Effects on flooding processes.
6. Restoration measures.
7. Monitoring results.

41. INTERDISCIPLINARY
MONITORING
The main aim of the Project at river Morava was to
• Re-structure the river banks
• Increase the lateral connectivity with wetland
areas
• Partly re-connect cut-off meanders
After the implementation of measures, the success of
the measures was assessed within a
interdisciplinary monitoring (2003-2005).
Eight different groups of organisms were chosen as
bioindicaors to cover the whole range of effects of
the measures on the entire river stretch and the
backwaters

42. Evaluation summary
phytobenthos
macrophytes
amphibians
dragonflies
makrozoo-
vegetation
benthos
birds
fish
type description
Total removal of outer bank protection
A1.1 + +/- + + +
with preventive erosion limits
Partial removal of river protection at
A2
outer bank
+ Initiation of steep flanks+ at the+outer bank
+ + +
B3*
Deposition of material at inner bank,
+
by (partially) removing+ bank protection
+ + + + +/- +
partial removal of bank protection
B4* Deposition of material at inner bank + Creation of sediment banks
+ + + +
C1 Reactivation of former gully systems + +/- +/-
at the inner bank +
+/- +
Reconnection of meander systems from
D1
downstream
+/- +/- Reactivation and +/-
+ + integration of
+/- +
D2
Initiations of outer banks in preparation
+/-
meander and gully systems
+/- +/- +/-
to upstream meander opening
E2 Relocation of bed sediments + + +
Installation of woody structures
E3 Installation of woody structures +/- + +
Partial removal of river protection and
F1 +/- + + + +
reshape to mean-flow groins

43. BIRDS
Indicator for river-bank connections
Steep concave banks are important breeding places for some
birds especially for the kingfisher
The study at Morava river showed that also artificially built
river sediment banks were settled by some species (e.g.
the little ringed plover)
A minimum size of 400m2 bank area should be aspired
Lateral connectivity increases the habitat quality of many
aquatic birds
Structual diversity demonstrably has a positive influence on
species diversity
[TEUFELBAUER & ZUNA-KRATKY, 2004, 2005, 2006]

44. AMPHIBIANS
Indicator for river-floodplain connections
The artificial built flat and muddy river banks at the Morava
river due to perfect summer habitats for juvenile frogs
Wetlands and flooded meadows are significant spawning
grounds for amphibian invertebrates
Therefore the lateral connectivity is very important for these
animals.
[WARINGER-LÖSCHENKOHL, 2005]

45. FISH
Indicator for the ecological situation of the whole
river system
The arising results of removing bank protections are pools
which are suitable habitats for many adult fish.
Furthermore structural diversity and wooden nests increased
the number of individuals of the dominant fish species in
the Morava river, like carp, catfish and bream.
Flat overflowed banks (riffles) have positive effects on
rheophile river fauna
Overall 36 (2004) different species were located with a high
ratio of endangered fish.
The reactivation of former gully sytems and side channels
increased the number of individuals of indifferent and
stagnophil species.
[SPINDLER & WINTERSBERGER, 2003, 2004, 2005]

46. MACROZOOBENTHOS
Indicator for waterbody structures and organic load
The removal of the river bank protection in the Morava river
mainly reduced the individuals which are not typical for
that location.
In fact the typical local species creates an increasing number
of individuals.
The flattening of concave banks leads to high biocenotical
ratio. Flat banks are very essential habitats for the
characteristical macrozoobenthos invertebrates in the
Morava river.
Also the connectivity to former gully systems and side
channels led to a higher biocenotical ratio and reduced
the number of untypical individuals.
The artificial installation of woody structures showed also
positive effects.
[GRAF & BLOCH, 2005]

47. DRAGONFLIES
Indicator for structural heterogenity and lateral
interaction of the river with its forelands
50% of the identified taxae are endangered according to the
“red list” of Lower Austria.
A high portion of the found taxae are sensitive and serve
therefore as a good indicator.
Removal of bank protection has a positive impact on the
dragonfly- fauna.
Created sediment banks are used by dragonfly larvae and
therefore essential habitats.
These banks already show a fully developed coenosis of
certain species as well as a high density of taxae.
The implementation of woody structures has a positive
impact. The increase in structures is evaluated
positively.
[SCHULTZ, 2005]

48. MACROPHYTES
Indicator for river structures and lateral connectivity
80 taxae could be identified during the field investigation
29 taxae of these are listed no the “red list”
The aquativ vegetation can therefore be accounted as very
specious and valuable.
The removal of riverbank protection created habitats for
pioneer vegetation.
Increased stream curvature and stream velocity variability
create a range of new habitats for a range of
endangered taxae.
New sediment banks provide habitats for site-specific plants.
The created water-foreland interaction zones induced a
significant increase in taxae.
The dimension of measures set had most influence on the
aquatic vegetation.
[PALL & MOSER, 2005]

49. PHYTOBENTHOS
Indicator for the contaminant load of the water body
118 taxae could be identified during the field investigation.
Only two taxae of these are listed on the “red list”.
Region-specific reference-taxae made up to 40% of the total.
No significant change, caused by the set measures could be
identified. This goes well with experiences from other
locations.
Structural changes therefore don’t have a significant impact
on water quality.
[PFISTER, 2005]

50. VEGETATION
Indicator for the change in interaaction with the
forelands on different sites
21 taxae of neophytes could be identified in the investigation
area
The high spatial and temporal variability of the outer banks
are evaluated as positive indicator
The presence of the winged saltbush (Graumelde), on created
sediment banks can be seen as a great success.
The permanent succession furthermore leads to a constant
change in vegetation
The change in water supply of the surrounding areas induces
a gradual change in the vegetation ecotype.
The reactivation of meanders and gullys therefore is seen as
a positive aspect.
The reinstalled interaction of the river with the foreland allows
to reestablish the typical potamal flood plain ecosystem
[LAZOWSKI, 2007]

51. OVERALL CONCLUSIONS
The analysis shows that for most of the biota the
implementation of measures lead to an
improvement of the habitat quality.
Especially the interaction between river and wetland
improved significantly.
The results of the study are important for river
restoration projects of lowland rivers and will
provide useful information for the
implementation of the program of measures
according to the EU Water Framework Directive

52. THANKS FOR YOUR ATTENTION
Acknowledgements to clients and partners
via donau –
Österr. Wasserstraßen-Gesellschaft mbH
Austrian Waterways Assoc.
Regional Government of Lower Austria –
UBA Austrian Environment Agency
and all project partners
for excellent collaboration.!
riocom - Albert Schwingshandl
albert.schwingshandl@riocom.at