Wildernis Consultancydrs Willem Overmars, landscape architectRhedense Veerweg 5-128976 EC Giesbeek, Netherlands0031.31.313.630.198Willem.Overmars @wildernis.com

Vision for the Danube Delta,a natural gateway to Europe

Ecology and Economy in Harmony

Background paper 7:Shipping on the Lower Danube between the Iron Gates and the Danube Deltaproposals for projects and model sites1st draft, 30th of July 2006Commissioned by:WWF International – Danube Carpathian Program, Vienna

Cover: fig. 1. Islands in the Lower Danube. They slowly move sideward from one side of the river to the other, becoming eroded, and silting up anew on a stable location in the river.

Contents

1 Summary

1.1 The dances of the river

Living rivers always dance. They dance side ward in large bends, and these meanders dance forward down the valley, and the rivers dance vertically between deep pools and shallow riffles. Its really dancing, as all this happens in a rhythm.

The time scale on which these turbulent and beating events happen is too large for human beings. We only see the short-time rhythmic cycles of floods and low waters, of the yearly returning events. For the really big rhythmical changes, the movements of the meanders and the disappearance and return of the islands, humans simply live far too short to notice.

Every river has its own rhythm. This depends on many things: how the rain falls, where the mountains and plains are situated, how steep the valley is, how much water comes down.

A long river, like the Danube, passes many landscapes. Upstream, the Danube is in places a vivid, quick reacting river. Below the Iron gates however, the Danube is slow, and large, and steady. The mighty river goes over almost 1000 kilometres hardly 40 meters down to the level of the Black Sea. It almost flows because it was used to do so before. Even in the Black Sea it goes on flowing – the river can be traced to Istanbul.

So the river forming processes are accordingly slow. The sediments the river can transport are light: fine sands, and silt. Erosion goes slowly, sedimentation keeps pace. According to old maps, it takes the river centuries to change its course from southern side of the valley, the high lands of Bulgaria, to the northern side – the terraces of the plains of Romania, and centuries for the way back again.

Old maps are often used in these background documents. Not because any historical situation is in itself of any particular interest. Old maps are used to enlarge the time scale on which humans can look at the events that happen to the river. To understand the real life of the rivers we have to look at them in 4 dimensions over a period far longer than our own lives, with the changes in time as the eye-openers for us short living creatures.

The understanding of temporal dynamics, or the changeability in time, is essential to grasp the true nature of a river. This notion, however, is necessary if we really want to restore the essential rhythmical nature of the long living, slow moving giant the Lower Danube is.

1.2 The forgotten river

Quite another feature is, that this part of the river is the forgotten part. Random samples of two centuries of travelling guides and landscape descriptions of the Danube show any amount of interest to cities and historical places in Germany, Austria, Hungary. Then Beograd is always prominent, then, of course, the cataracts of the Iron gate. After that the travellers jump to Ghiurghu / Russe, then to Braila / Galaţi, and quickly to Sulina. The last 1000 kilometres hardly get 10 % of the contents of the guidebooks.

The beautiful thing about being forgotten is, that for a long time no one really cared. In the 19th and 20th century, everyone in Europe and America was busy 'normalising' or canalising the rivers. The Danube didn't escape this fate. The river was canalised with dams almost completely in Germany and Austria. It was strongly normalised (= brought to equal width and depth, and closed off from side arms) in Hungary and downstream to the big dams in the Iron gate.

But the long stretch between the Iron Gates and Braila seemed to escape this fate. The 19th century concentrated on the stretch Braila - Sulina – the gateway from the grain producing plains of Wallachia and Moldova to the international trade on the seas. The

Turks, who occupied the area for many centuries already couldn't care less. The British engineers who “ improved” the river at Sulina, restricted themselves in improving the harbour facilitaties of the main towns along the river – the grain that grew on the fertile plains had to be loaded to ships going to Braila. The Danube after the contributions of the Sava, the Drava and the Tisza was apparently large and deep enough for the ships of those days.

On most places, indeed, the Danube is 4, 6, 8 or even over 20 meters deep. The rhythmical character of the pools and riffles in the river brings shallows every 10 – 20 kilometres.

In these shallow areas, sandbanks are formed, which, with a vegetation of alluvial forest, which grows on islands. The deepest parts of the river on these shallow places are still 2.50 – 3 meters deep in periods of low water. Deep enough for the steamships of the Erst kk priv. Donau Dampfschiffahrts Gesellschaft, that connected Habsburgs' Austria to the open seas from 1837 onward. Deep enough for the ships that brought the grain to feed the British Empire to Braila. Deep enough for fleets of warships during the two big wars of the 20th century. Deep enough for the long chains of towed vessels, and later the pushed convoys of the large fleet of cargo ships in communist's times.

As the river was simply wide and deep enough, there was no need to spend the enormous sums needed to ' improve' the river. A bit of dredging in times of low discharge did the job good enough.

Thus, this part of the river remained up to these days in a relatively natural state, with moving sandbanks and islands.

1.3 The forelands lost

The disaster to the naturalness of the river happened along its shores. The Danube was accompanied, especially at the northern, Romanian part, by an up to 28 kilometres wide stretch of river forelands, with deep and shallow lakes, old river arms, low lying meadows, high riverbanks, and on some places dunes. Here the villagers kept there cows, horses an sheep. Here the fishermen caught a overwhelming richness of fish. Here the fish spawned on the grasslands that were inundated during the long spring floods of the river. On high places, there was even some arable land. The land was covered with fruit trees. All this in a setting of a mosaic of patches and galleries of alluvial forests.

In the 1930-ties, plans ware made to improve this landscape. The first plans were relatively modest. Only the very highest places should be embanked by a low dyke, with a frequency to become overtopped of 1 in every 6 or 7 years. The lower parts should be used for forestry, and as meadows. Regular floodings were considered to be necessary for fish reproduction. And the lowest places should be used for fishing.

In the sixties and seventies however, these old plans were forgotten. In fact almost all of these ecological extremely valuable as well as for the villagers' income generating lands were embanked, and changed into agricultural polders or fish ponds. This proved to be unsuccessful, however.

The embankment of the sixties was done in a really maximalistic way. Almost no riverforelands, the place to accommodate the spring floods, were left over. The Dutch, in a 800 year long history of trial and error, had learned to leave wide stretches of land to the river. Along the Danube, the dykes were built as near as possible to the river.

This embankment stopped the horizontal dancing of the river in slowly moving meander bends.

The situation now is, that the river bed itself is relatively natural and untouched. The vertical dance is still going on. There are almost no river forelands. The dykes are far to

near to the river, and therefore in danger to break. Behind the dykes, half abandoned polders are waiting for restoration. In the narrow area between the dykes, floods are concentrated, and become threatening for nearby villagers, in case of inundations through breaking dykes.

Fortunately, there is, in the Danube Delta Green Corridor, an initiative and agreement to restore large parts of the river valleys in there natural state. It is, however, important that not only the former biotopes and habitats are restored. The very forces behind the existence of these habitats must be revived. The 4th dimension, time, has to be included, and the floodplain must be given back to the dynamic processes of erosion and sedimentation that causes the Lower Danube to dance his own centuries long rhythm.

1.4 The new threat: overperfectionist bureaucracy

In the same time, however, a new threat for the river arises. In its infinite bureaucratic wisdom, the EU has declared that international, main waterways should have a deptht of 2.50 m in times of low discharge. Margins of uncertainty added to this number, and the space between the ship's hull and the bottom of the river calculated with, the Danube should be 3.00 – 3.50 m deep. The Lower Danube is not deep enough for bureaucracy.

To achieve this, there are 2 technocratic possibilities. The first is dredging. To achieve this depth however, dredging has to be deep (up to 3.50) to allow for some silting up in times between dredging. It will be very expensive, it will disturb the river bottom continuously, and ruin life in the river.

The second way is to build parallel dams and groyns at nearly all shallow places.

This will kill the river. It will flatten out the vertical rhythm, as the sand of the shallows will be forced into the pools in between. It will stop the horizontal meandering as well. Both the horizontal as the vertical dance will come to an end.

6 Where is the problem ?

The Danube is a part of the pan-European Transport Corridor nr VII. Other parts of this main European shipping axis are the Danube-Main-Rhine Canal, the Main, the Rhine, Meuse and Scheldt.

A comparison:

The Lower Danube has a length of about 1000 km. The forecast for the traffic volume for 2015 shows a growth from 16 million tons in 2000 to 25 million tons in 2015. (Harris p 5-10). On the river Rhine in 2005 a volume of 200 million tons was transported. The Rhine is 1000 kms long as well, but is a far smaller river. Even in the lower Rhine, the discharge in times of low water is 1/6th of the discharge of the Lower Danube. So where is the problem ? Compared to the Rhine, ships will hardly meet each other. Even if one-lane traffic is necessary on certain spots, this is easily organised by traffic control. On the busy river Rhine its a normal situation.

On the river Rhine, there are numerous spots where the EU recommandation of a 2.50 m river depth (not draught, depth) is not met with. Even the perfectionist Dutch Rijkswaterstaat had, in 2005, a 120 day long period of only 2.20. In Germany acceptance of a lower depth in cases of lower discharge is even bigger. Depth of less then 2 meter occur. This is to a certain degree accepted. The remedy is, that the big ships have a disadvantage in certain periods: they can load only partially. Smaller ships of smaller companies however, flourish in the periods.

So, if 8 times more traffic on a river that is 1/6th of the size and regularly has not enough depth can be handled satisfactorily, why should the Lower Danube be normalised ? And if

German and Dutch water managers accept a known and regularly returning under performance of the river, why shouldn't this be applicable to the Lower Danube, part of the same Pan European Transport Corridor nr VII. Are there different norms for the same waterway ? The solution is more in traffic control than in dredging or groynes.

1.5 Adapt ships to the river, not the river to the ships

There is luckily another solution. The two mentioned technocratic solutions, dredging or groynes, rely on 19th-century technics. There is no self-evident necessity to follow this way. We don't behave in this way in other instances: we abandoned steam long ago.

A far better solution can be found in the opposite direction: Don't adapt the river to the ships, but adapt ships and shipping to the river. In the case of the Lower Danube, a very large river, even most of the shallow areas are deep enough for large modern ships which are built for these circumstances.

The actual fleet on the Danube is in a state of complete rustiness. A new generation of new ships has to be built. New cargo's will wait for transport: containers, roll-on-roll-off trucks. Bulk transport as ore and coal will become obsolete. So the first part of the solution is to build modern ships for modern needs with a draught of up to 1.50 meter. Examples are already built, and on the river. Catamarans seem to be the answer.

The second point is, that shipping itself is changing. All Danube states have already modern digital maps ready, or almost implemented. Digital maps of changed situations or accidents can be transferred to ships at any moment by email – the ideal solution on a river with changing sandbanks. GPS makes navigation, in combination with these maps, far more precise than it used to be.

Conclusion

So, the future is for a dancing river, with a natural floodplain, carrying modern vessels which are guided by state of the art technologies through an archipelago of wooded islands to prosperous harbours.

2 Sediment transport

2.1 Dwindling quantities

The river Danube carries every year 30 million tons of sediments to the Delta. Only silt and fine sands reach the delta, due to the low velocities of the current in the extremely flat Danube Delta. 1.5 million tons is sedimented in the delta itself, and is thus used for the vertical growth of the Delta. By far most of the sediments is not used in the delta, but just passes it. The remaining silt disappears into the Black Sea. The remaining sand is used for the expansion of the delta. The amount of sediment influx to the Delta has decreased sharply during the twentieth century. From 67.5 million tons/year in the period 1921 – 1960 , to 41.3 million tons/year in the period 1971 - 1980 , to 29.2 million tons/year in the period 1981 - 1990 . (Monteanu 1996-2 p 27)

19th century heritage

In the 19th century, the vast plains of Romania were used for the production of grain for the vast growing population of western Europe. Opening up the soils of these plains, caused a strong increase in erosion. This resulted in a rather sudden increase in sediments in the river. The high discharge of sediments in the 19th and the beginning of the 20th century is partly a result of the new agricultural practices. To some extent the decrease in sediment transport after 1960 can be seen as a return to a more normal situation.

From surplus to shortage

The “ return to normal” means regrettably not the return to a more natural situation. The building of dams is responsible for the fact that sediments are caught in the lakes before the dams. This decrease is caused by the construction of dams in the tributaries of the Danube, and in the Danube itself.

This what the roof report says about damming and sediments:“ Dams and weirs have an important effect on natural sedimenttransport. Studies in Germany have shown, that a former load of180 000 tons per year from the River Lech into the Danube decreasedto nearly zero by 1960. The same can be said for River Inn, where aformer 540 000 t/a of sediment transport was decreased to 180 000 t/aby 1960 and is today nearly zero31. Interruption of sediment transporthas two important effects. Upstream of a dam the sediment is retainedand often has to be extracted or flushed out during floods to maintainriver depth for hydropower generation and navigation. For example,gravel extraction of approximately 15 000 m3/a is necessary on theRiver Traun on the impounded section of Abwinden–Asten in Austria,which acts as a sediment trap32. In the backwater zone of the IronGate, 325 million tons of sediment accumulated between 1972 and1994, and fill 10 % of the entire reservoir capacity.Downstream of dams the loss of sediment transport requires artificialdonation of material to stabilise the river bed and to prevent incision.This is the case downstream of the Freudenau dam where addition of160 000 m3 bed load per year is required33. Immediately downstreamof the Iron Gate Dams, incision of the riverbed is monitored, as aresult of change of flow and sediment regime. The overall reductionof sediment transported by the Danube over long-term leads to

intensive erosion on unregulated banks and islands in the LowerDanube region, e.g. Tcibtriza-Island, Belene Island, Garla Mare,Calafatul Mic or Cama-Dinu. Increasing coastal erosion along the244 km stretch of the Romanian seashore between Musura arm andVama Veche, an area which represents 6 % of the total Black Seaseashore, is also partly caused by reduced sediment transport by theDanube. Recent measurements (1980 - 2003) of erosion processes atthe sea-land interface have indicated that erosion is more accentuatedin the northern area of the seashore (Sulina – Vadu).

The use of “ white coal” , long regarded as being environmental friendly, has proven to be disastrous for natural rivers. In the case of a nearly total exploitation of this energy source, the complete watersystems of countries like Sweden, Austria and Switzerland are ruined.Happily the report “ rivers at risks” of WWF is the start for opposition.Normalising the lower Danube would lower both the amount of sediments annually transported, as the amount of sediments in stock to become transported in later years and centuries.

2.2 Dancing rivers

2.2.1 slow transport

Sediment transport in a river takes various forms and uses different processes at different times. The first one is a kind of steady transport of silt ( in suspension in the water) or sand, rolling over the bottom, in times of low discharge.

In case of a flood, during the rise of the water the force of the river increases, and thus its capacity to erode and move sediments. In these periods, the river starts moving more and more sediments that where formerly in rest. In the lower Danube this can take the forms of large moving underwater sand flows, moving with a velocity of 1000 meters / day. After the peak of the flood, flow energy decreases again, and the river starts to drop the surplus of sediments.

This means, that sediments often are transported over a short distance. It is taken up, transported, and deposited again. In the hypothetical case of a grain of sand which is moved by a spring flood over a distance of 10 km, it would take 100 years to travel the distance from the Iron gates to the dunes of Sf. Gheorghe.

More often, such a grain will not be moved every year. If it is deposited by a side current into the floodplain at some distance of the main river, the grain could easily remain in rest for hundreds of years before it is transported again.

The concept to understand is, that in fact, the whole stock of sediments in the full width of the river is slowly moving downstream.

2.2.2 The vertical rhythm

In longitudinal direction sandy rivers form dunes. In another hypothetical case, the water just passes a shallow place, an underwater dune. It gains velocity, and with new energy takes up particles of sand. This erosion causes the deep areas between the dunes. After a few kilometers, however, the water with the sand meets the next shallow place. It slows down, and loses its transport capacity. It drops the sand at the next underwater dune, or sandbank. After it has passed the shallow area, it gains speed again, and starts to transport new particles of sand with new energy.

For shipping, the deep pools between the shallows are easy. In the shallow areas,

sandbanks form, islands develop. Important is, that although the longitudinal situation of these banks and islands is relatively stable, the sand they are made of is changing continuously. A sandbank has to grow at one side, and simultaneously erode at another side. The beautiful thing is, that the position of the islands roughly remains constant, while the materials they are made of, are moving downstream.

The distance between the shallow areas with sandbanks and islands is a function of many factors. The discharge, even the rate of change in the discharge of the river, the peak discharge, the width of the river, the rate of change in width, natural obstacles ,the consistency of the available material, the slope of the river, all these factors determine in the end how the river behaves.

Fig. 2. The vertical rhythmical dance of the Danube between km 740 and 600. Source : DDSG, Die Donau von Ulm bis zum Muendung, ca 1911.

2.2.3 19th century remedy

These shallows are a nuisance for river managers. There are 2 main 'problems' :

shallow water easily freezes in winter. Moving ice develops easily in the shallow waters. At the next shallow area, moving ice than forms dams in the river, which in turn causes inundations. Often such inundations are much higher than normal floods.

Shallow parts in the river are difficult for large ships.

Nineteenth-century's engineers invented the following remedy: Try to make an even flow of water, without changes or interruptions. Side channels had to be closed to avoid loss of water and hence differences in

transport capacity Groynes and lateral dams should guarantee an equal width of the river.

This was called “ normalising” the river. Changes in transport capacity, which caused the river to dance, were eliminated. In many cases, the rivers themselves carried the sand of the shallow areas into the pools in between.The upstream part of the Danube was treated in this way. The Rhine and Elbe as well. The lower Danube escaped , probably because of the fact that the river was so large and deep, that even at shallow places the ships, even the large push convoys of the last 50 years, could pass.

Fig. 3. Alternation of pools and riffles in the Danube near Calarasi and Cernavoda. Source: Carte de Pilotage, 1992.

2.2.4 Side ward movement

A river like to lower Danube makes sideward movements as well. Water dislikes to flow along a straight line. Due to differences in resistance, water starts to make bends. It wants to lengthen its way down, and decrease the slope of the riverbed.In a outer bend, water starts spiralling: a vertical current goes near the riverside downwards, from the surface to the bottom of the river, perpendicular to the main stream, like a corkscrew.This spiralling current has much erosive power, as the water in the upper layers of the river are without sediments. So, material is eaten away in the outer bend of the river, transported over the bottom to the inner part of the river bend, where it is deposited. Often the material eroded from one outer bend, is deposited in the next inner bend.Thus, a river moves side ward, as well as slowly downward.If the valley is wide enough, such meanders may developed to very large bends, which in the end become cut off by the river itself (Kopaci Rit, along the Danube).In a valley with limited space, the river tends to move from one side of the valley to the other side, and back again, limited by the terraces (or dykes) at both sides. This is exactly what happens in this part of the Danube.

Fig. 4. Floodplain downstream from Dabuleni (km 670 – 600). (Source: Military map of Austria, 1918. Oesterreichische Nationalbibliothek, Wien)

An example is the valley downstream Dabuleni (km 670)(fig. 4). South of the river is Bulgaria. The hills there are up to 170 meters high. The floodplain is discernible by the river itself, and the blue coloured marshlands. The upper part in Romania is a terrace, about 50 meters high.In the left part of the map, the river flows directly underneath the Bulgarian hills. In the right part, the river has crossed the valley, and flows underneath the Romanian terrace. In the configuration of the lakes and marches is visible, that this has been the opposite as well. The rate of changing of this river however is so slow, that there is no sequence of historic maps to make this visible.

According to Google Earth, (fig. 5) in 2006, the water level of the Danube is on a height of 21 meter. The deepest point of the cultivated former marshland (the bottom of the former lake) is lower than the river, 20 m in height.

fig. 5. Dabuleni, the same area as fig 4. Dykes are made almost directly along the river. the marshes and lakes are dammed in. Google Earth 2006.

Fig. 6. Dabuleni, inundations of April 2006.

The combination of a low polder, with dykes too near to the river, is a clear recipe for inundations.

Fig. 7. Belene island. (Military map of Austria, 1918).

At Belene in 1918 the Danube was in “ full speed” moving to the north. The northern shore of the Danube shows signs of erosion – the small fragmented islands, 'left overs' of half eroded parts of the northern shore.Full speed means: several centuries.

Fig. 8. Belene Island in 2006. Google Earth.

In 2006, the side ward movement in the Danube is almost completely stopped by the embanked of the floodplain, made between 1960 and 1970.

The consequence is, that from those parts of the plain, the sediments are no longer available for the river, and, in the end, for the delta.

2.2.5 19th Century remedies, part 2

The 19th century engineers were not happy with side ward movement. It obviously brought much sediment in the river. Sediment which had the natural inclination to organise itself in riffles and pools. Exactly the kind of things these engineers were fighting. Side ward movements were easy to stop – by lateral dams and by groynes, and by embankment of the floodplain.

2.2.6 Continuity of islands

Islands are under the influence of both movements. The rhythmic formation of riffles and pools, and the sideward movement of the meanders.

Fig 9. islands in the Danube at km 710.Island have a remarkable continuiteit on there locations. Although they are continuously eroded, and built anew with new sediments, the longitudinal rhythm keeps them more or less on the same location.

Fig. 10. Eroding top of the island.

The top of the islands on figs 9 and 10 are eroding. A few large trees are left from the former alluvial forest. The sand lies open. The ridges remind of the last flood.This could be a natural situation. As these islands (km 711) are near to the iron gate dams the erosion could be a result of sand-hunger of the river, caused by a lack of sediments from upstream.

Fig. 11. Old alluvial forest

The island at the left is the oldest. It shows a canope of large trees. The light green-yellow dots probably are Acer negundo trees, the American invader in the European alluvial forests. Silver grey are willows, Salix alba. Dark green are poplars, or even oaks and ash, if the island is old enough. In between possibly grow wild pears and apple, elm and lime.The island is eroding, as the old trees at the left grow directly at the shoreline. Trees have been fallen from the shore into the river.

Fig. 12. Young and very young willow forest on young sandbanks.

The island at the right is younger. It is more uniformly covered with the silverish – grey color of willows. The trees are smaller and younger. The island is growing at the lower parts – zones with very young even-aged willows are

signs of surfacing sandbanks, which immediately become overgrown with willows.

The island at the left developed a long and narrow stripin the area between the two islands. Its covered with relative young forest. So, even the oldest, eroding island gets a new life at the north side.

This is the very dynamic way of survival of these moving islands.

2.2.7 Natural forests

The alluvial forests on these islands tell the story of their hosts. The trees germinate the very moment the sandbanks are high enough to surface. The lifespan is determined by the time the island survives. In steep, fast rivers like the Allier in France, (going down 75 cm/km) willows and poplars become mature. But oaks, who are late to settle themselves, and grow slowly are never older then 30 years. According to old maps in the river Waal in the Netherlands (going down 15 cm/km) it took 150 years for an island to travel from one side of the river to the opposite shore.Here on the far larger but slower Lower Danube (going down 2 or 3 cm/km) it must take centuries.To tell this story, in restoration plans the forest should be allowed to develop spontaneously – otherwise they can't tell this beautiful story. The only other natural force

that should interfere is grazing. Never plant alluvial forest – its forgery.

(stories in italics indicate in telegram-style the subjects to be told later:)

Living and dead wood in the river – importance for fish.

2.2.8 Dykes and poldersSee text on dykes in the seaside report. - No dykes, - Restoration of habitats by making a break in a dyke is the job half done – Remove dykes almost completely – parts could be maintained as mounds.

2.2.9 change fixated sand into moving sand: the long way to the Black Sea

Sediment transport is NOT a short, continuous journey through the river. It is an interrupted journey, governed by the lateral and longitudinal movements of the river. It takes centuries for a particles of sand to pass the Lower Danube. Embankments mean the very loss of far the greater part of this sand – it gets out of reach of the river.

2.2.10 Dams and groynes

Dams and groynes are the 19th century's tricks to normalise a river, that means, to fixate the sand.

2.2. 11 Danube Green Corridor

A very nice , beautiful and promising project. I hope I will have made some contributions in the field of river dynamics and the management of natural forests.

3 Shipping

3.1 National shipping companies

3.1.1 Connexion to the seas: Sulina / TriesteIt is not certain that the axis Rotterdam-Constantsa indeed will develop as a busy route. Its to far, and the route on the sea over the Mediterranean is far easier, quicker and cheaper.In the 19th century already, the middle Danube region – austria, hungary, Yugoslavia – looked for a shorter way to the seas: by train to Trieste.The english in the 19th century were interested in the lower Danube only up to Braila.

3.1.2 Austria on Sea: DDSGFor the Austrian Monarchy, the opening of Sulina harbour meant Vienna at Sea. The DDSG made this promise true by passengers and cargo ships.During the communist the river was much used for heavy traffic. This fleet now is almost obsolete.

3.2 Dreams of the future: axis Rotterdam – Constantsa

3.2.1 TenT - Traceca[ to be added – sea report on shipping)Main message: 19th century technics are needed to accommodate the ships with 2.50 m depth. This is the main danger for the Lower Danube and for the Delta.

3.2.2 Roof Reporthm until now – info.

3.3 Phare report

3.3.1 Development of the plan

In 1996, the European Commission decided to carry out the “ Study to improve Navigation on the Danube in Bulgaria and Romania” within the framework of the Phare multi-county Transport Program. The contract was awarded to Frederic R.Harris BV, who carried out the study in collaboration with Dutch, Bulgarian and Romanian firms.

In the years before 1996, preliminary studies were already made for the Government of Romania:

– River status report, 1994

– Danube River development strategy, interim report, 1995

– Danube River development strategy, draft final report, July 1995.

In the Final Report the recommendations are:

This meant the continuation of the existing situation, and amelioration of the situation around Cernavoda.In the Phare report, new facts and insights emerged.The analysis of the problems (the shallow areas) looked as follows:

The recommandations were as follows:

This meant the “constriction” (normalising) of many of the shallow places in the river over length between 2 and 15 kilometres.

Through these works the enormous Danube should be “ constricted” to a width of 800 meters by a 100 % guaranteed depth of 2.50. By comparison: the width of the river Rhine in the Netherlands, with 8 times as much traffic, is 150 meters.

Fig. 13. Proposed constriction works at Batin Island. (Source: Phare report)

Fig. 14. Island of Batin, 1911. (Source, DDSG, Karte von Ulm... 1911)

3.4 The threads

3.4.1 back to fixation of the sandNormalisation by gruoynes and dams is fatal for the river.

3.4.2 influence on the delta

for continuity of growth on the short, middle, long very long timescale, the full supply of sediments of the floodplain of the lower Danube should remain within reach of the dynamic processes.

In addition to the shortage of sediments due to dam building, this will further dramatically reduced the amounts of sediments. Not improbable that there will not be enough sediment to feed the delta.

3.4.3 the sinking riverNormalisation means a constant “ starvation” of the river. The sand hunger will result in a riverbottom as flat as possible – but, in the end, always going down. Normalised rivers without a stone bottom slowly sink away in the landscape. They become narrower and deeper, and loose their connection with the wetlands, which dry out.

4 Alternatives for shipping

unique opportinity: this river is big enough to do without constrictions. Its complete overkill. Take the opportunity to develop shipping on a living river.

4.1.1 modern ships

Duisburger colloqium; roro-ships, catamarans (cruiseship, sea doc on tourism)

4.1.1 new cargos

4.1.2 new river guidance

4.1.3 GPS

4.1.4 ENCENC is a new guidance system, already in place in Austria, Croatia, Serbia parts of Romania. Planned for Hungary, Slovenia, Ukraine. It consists of digital navigation maps, instantanuously replaceable and updatable according to circumstances.

(sea websites of via-donau en sevenCS for demonstration software) seemyENC

4.2 partnerships

- consultancy (Haskoning ?)

- shipbuilders

- shipping companies

- governments (?)

4.3 Projects.

4.3.1 model sites: islands with natural alluvial forests ( no planting)

4.3.2 eroding / growing islands in “ not to be constricted” areas (islands on cover) to show the principles of moving islands

4.3.3 floodplain restoration in combination with side ward movements (ch 5)

4.3.4 Large international attention for the threat of loosing the last big semi

natural river. (The Wolga is almost completely dammed)

5 Floodplain restoration

5.1 Existing plans of Danube Green corridorPlace these beautifull plans in the general context of the living dynamic river concept of the dancing river.

Bibliography

ICDPR, 2005 Roof report, Budapest. - implementation of the Water Framework Directive

Maps:Commission du Danube, 1992. Carte de Pilotage du km 375 (Calarasi) au km 171 (Braila)

Annexes

Roof report:

4.4.4.2. Flood defence measuresMost of the larger rivers in densely populated areas are characterisedby anthropogenic modifications for flood protection and to secureland for urban development. In many cases, hydro-engineeringstructures have multiple purposes often resulting in changes of theriver character, e.g. straightening of a meandering or anabranchingriver. These changes affect not only the river itself but larger areas ofthe valley floor.Major systematic regulations for flood defence and navigationpurposes began in Austria in the 19th century. On the presentterritories of Hungary, Serbia and Montenegro, Bulgaria andRomania first dike systems for flood protection along the Danube

were already built in the 16th century, but were intensified in the 19thand 20th century. The former extensive floodplains with numerousside arms and backwaters were largely altered into canalised andstraightened waterways with distinct river bank reinforcement. As aconsequence, today only less than 19 % of the former flood plains inthe Danube basin, compared to the situation 150 years ago, remain.The area of floodplain affected by river regulation/flood defence islarge – in Hungary for instance 2.12 million ha were diked.These facts point out the basin-wide importance of river regulationworks and flood defence measures. The major pressures resultingfrom flood defence are “alteration of the river course and channelform/profile”, “flood defence dams, set-back embankments, dykes”,“alteration of the hydrological/hydraulic characteristics” and“alteration of the bank vegetation and banktop land use”. Comparedto pressures resulting from hydropower generation, where thedisruption of the longitudinal continuity is most important, flooddefence measures affect mainly the lateral connectivity.In the upper part of the Danube in particular, river regulation worksfor flood defence often go hand in hand with alterations due toimpoundments. The effects of these alterations on the river overlapwith one another. For example, on the rivers Inn, Salzach and Ennschains of hydropower plants are built and almost the entire river

stretches are strongly regulated. On the Inn, for example, less than20 % can still be classified as free-flowing which means notimpounded or not strongly regulated.The Danube itself is regulated along over 80 % of its length. Due tohydraulic works aimed at navigation improvement oxbows have beenlocked or filled up, and major floodplain complexes separated fromthe natural hydrological conditions of the Danube. Discontinuitybetween the river and its accompanying floodplains reduces thehydrological connectivity leading to changes in frequency andduration of floods and degradation of the former floodplains. Theexamples for loss of flood plains are manifold. In the 19th and 20thcentury, altogether 15-20,000 km2 of the Danube floodplains were cutoff from the river by engineering works34. On the Tisza Riverdrainage projects reduced a formerly large floodplain to a verynarrow one, resulting in an 84 % loss, from 7542 km2 to 1215 km2.The meandering river bed was shortened by 32 % by river regulationworks. Today, the Tisza can be classified as strongly regulated alongmore than 70 % of the total river length.31 BANNING (1998).32 SCHIMPF & HARREITER (2001).33 SCHIMPF & HARREITER (2001).34 KONOLD & SCHÃœTZ (1996).

In the Sava River area, in particular in the area of the Nature ParkLonjsko Polje, there is an example of possible co-existence betweenthe complex solution of flood control and conservation of natural,landscape and cultural values of national and internationalimportance.In the Danube Delta, more than 100,000 ha (most of themtemporarily flooded areas) were embanked. It must be noted thatbetween 1994 and 2003 about 15 % of the area with embankmentshave been re-connected to the natural influence of water, throughecological restoration works. In the Razim-Sinoe system coastal area,an amount of 23,500 ha have been embanked. The separation of themain river from the backwaters results in a loss of habitats, whichaffects the aquatic fauna and flora (see Chapter 4.5.1.4).Large dikes and disconnected meanders and side-arms also reduce thedynamics of the groundwater by suppressing the exchange of surfaceand groundwater. This is important for re-newing river bank filtrateused for drinking water supply.

4.4.4.3. NavigationNavigation routes in the DRB are restricted to the Danube itself andthe lower portions of some tributaries (see Map 7). Regulation worksfor navigation in the Upper Danube region started already in the 19thcentury and led to a straightening and shortening of the main Danubebed and creation of one main channel for navigation. In LowerAustria for instance, lateral dams were built between 1898 and 1927to narrow the river width. In Hungary, the Danube was shorted bycutting-off meanders from 472 km to 417 km.35At present the Danube is navigable from Ulm down to the DanubeDelta. From Kehlheim (rkm 2411) to the Delta the Danube servesas an international waterway. These 2411 km are equivalent to 87 %of the Danube’s length. 78 harbours36 are located on the Danube

between Kelheim and the Black Sea. Therefore, navigation is ofmultilateral importance.In the upper part of the DRB, navigable tributaries are Morava(about 30 % of its total length), Raba (29 km at the mouth) andVáh (71 km, equals 20 % of the river length). The Drava is navigableon approximately 20 % of its length. The Tisza River is used as awaterway from the Ukrainian-Hungarian border to the confluencewith the Danube, which is over 70 % of the total river length.Some Tisza tributaries are navigable on shorter sections: Bodrog(Hungarian stretch and 15 km in the Slovak Republic), Mures(25 km, which corresponds to less than 5 % of its total length), Körös

(115 km in Hungary) and Bega (117 km in Romania and Serbia andMontenegro, which is over 48 % of the total river length). On Sava,navigation is possible on over 50 % of the river starting from Croatiadown to the mouth in Serbia and Montenegro.Additional artificial waterways were built along the Danube fortransport purposes. These include the Main-Danube Canal inGermany providing a link to the Rhine and the North Sea, theDanube-Tisza-Danube Canal System in Serbia and Montenegro,and the Danube-Black Sea Canal in Romania. A detailed descriptionof these waterways is given in Chapter 3.6.The (hydro)morphological alterations constructed for navigationpurposes are manifold and often overlap with changes from hydropowerimpoundments and flood protection. These include buildingweirs with sluices, regulation, canalisation and bed stabilisation.Unfortunately detailed quantitative information about pressuresresulting from navigation in the DRB is currently not available.One of the main pressures resulting from navigation is the effectsrelated to channel maintenance. Sediment excavation and flushing ofareas is undertaken where sediment accumulates and hampers navigation.Studies have shown that on the Austrian Danube, up to 60 % ofthe river bed deepening in several sections downstream Vienna wascaused by increased regulation and dredging activities for securingwaterway transport37. Yet, a recent ruling by the Austrian SupremeWater Authority only permits dredging in the Danube, if no more than50 % of the dredged material is used for structural measures on theriver banks and the rest of the material is deposited in the river suchthat it can be continuously mobilised by the flow of the river.In the lower Danube region, lateral river bed erosion dislocates thenavigation channel in the Danube. Additional river training works aswell as dredging of shallow fords to maintain the minimum shippingdepth are carried out. In the Danube delta, dredging is also animportant problem. Already at the beginning of the 20th century, butespecially in the last decades canals were dredged in the interior ofthe Delta. The total length of artificial water channels in the Deltacreated by dredging amounts to over 1,700 km, which is as much asthe total length of natural water courses.Other pressures related to navigation are e.g. alterations of theriver course or disruption of the lateral connectivity by detachingside arms, tributaries and wetlands, have been described earlier.Environmental impacts resulting from navigation are mentioned inChapter 4.5.1.4.35 IHD (1986).

36 via donau (2004).37 BERNHART et al. (1987).