POLISH VERSION



Home | Introduction | Download e-book | Conference 2001 | Special thanks | The note of law | Contact
Articles: Poland | Małopolska | Mazowsze | Ziemia Łęczycka | Żuławy | Nizina Sartowicko-Nowska | Ziemia Kwidzyńska | Ziemia Walichnowska | Ziemia Sieradzka | Ziemia Wieluńska
Articles --> Conference 2001

Marian Złonkiewicz

Drainage and Water Facilities Management, Bydgoszcz

Reconstruction and modernization of flood protection systems in the M±tawa Valley

I. Introduction

The flood is a natural phenomenon and river valleys were formed as a result of thousands of such occurrences. With the passing of time, the river formed wide flood plains characterized by a moderate slope, rich soils, and often a scenic landscape. From the dawn of history, river valleys provided an excellent environment for cities, communication routes, development of agriculture and industry. On the other hand, though, the risk of floods was always the price for the comfort of living in river valleys.

The flood occurs when the flow rate of water from precipitation and melting snow exceeds the capacity of the river bed. In those cases the river floods the adjacent areas and causes damages. Impeded water flow that can be caused by reduced capacity of the river bed is another reason for a flood. Such a reduction in river bed capacity can be a result of an ice jam or a backwater phenomenon caused by a storm at the mouth of a river.

Floods are responsible for economic and non-economic damages. The structure of the flood related losses depends primarily on the season, in which the flood occurred. During summer flooding, the agriculture suffers the greatest losses, while in other seasons, other economic sectors are at risk.

Humankind has put a lot of effort into eliminating or limiting floods through construction of hydrotechnical facilities associated with flood protection, among which the following are the most common:

- flood banks,
- river regulation,
- water structures, sluices, flood bank locks, pumping stations,
- flood gates,
- storage reservoirs.

These protection structures and operations may reduce the risk of a flood; however, its complete elimination is impossible. Failure of a dam, a flood bank, or a lock, or their improper operation may result in a flood. Irrespective of the direct flood protection in the form of above mentioned facilities, there are many other ways to influence the course of events during a flood and minimize losses. We can reduce the draining rate through forestation and proper development of the watershed area. We can also retain a part of the outflow in reservoirs or channel out the water excess through draining canals. These types of flood protection are particularly appropriate when a river flows through large urban areas, where expansion of a river bed or erection of high flood banks are impossible due to the reasons related to urban structures. The extent of damages can be reduced by appropriate development of the floodplain, proper design of buildings, and preparedness of the residents for evacuation. The effective hydrometeorological prediction system is another important method that may help to reduce the damages. In Poland, ca. 2 millions hectares of river valleys and coastal lowlands (7% of the country's total area) are subject to flooding, including 1.6 millions ha of very fertile and densely populated valleys of large rivers. A number of large cities, such as: Wrocław, and sections of Cracow, Poznań, and Gdańsk, as well as many settlements are located in river valleys. . The areas that are at risk of flooding are inhabited by over 1.5 million people. There are also many industrial facilities, warehouses, roads, etc. Due to high quality of soils, these areas are intensively cultivated.
Flood banks are the simplest and oldest form of protection of the river valleys against floods. Therefore, in a lowland country such as Poland, they were, and still are, used most often. First local flood banks in Poland were built in the 13th century. However, the most rapid intensification in flood bank construction occurred at the turn of the 19th and 20th centuries, in the interwar period, and between 1950 and 1970. Currently, there are 9415 km of embankments, which protect 1 million ha of areas situated in river valleys and in the coastal zone inhabited by nearly 1.5 million people.

II. General information

Flood hazard in the Kujawsko-Pomorski voivodeship occurs in a considerable area due to the region's location in watersheds of two rivers, the Vistula and Noteć. The Vistula poses the most serious threat. The course of the river in the mentioned voivodeship stretches for 206 km, that is, from the 859 km to the 653 km, from Pieni±żkowo to Skoki Duże.

Located on both sides of the Vistula, these areas are protected by flood banks with a total length of 180.9 km and constitute a surface area of 40558 ha, including valleys of the Vistula tributaries. The river valley of the M±tawa river, called Sartowice - Nowe is one of the areas with the highest risk.

The valley is located in the northern section of the voivodeship, at the border with the Pomorski voivodeship. The M±tawa is its main flowing water body. Its length equals 57 km and the watershed surface area, 460.3 km2. The watershed can be divided into two sections: the valley section with the area of 213km2 and the upper watershed section, which covers 247.3 km2. The upper section of the watershed is highly forested (ca. 65%) with numerous lakes and mill ponds and is characterized by high retention and balanced outflow. The springs of the M±tawa river are located in the vicinity of M±tasek lake at the elevation of 80 m above the sea level and its mount in the village of Kończyce at 12.0 m above the sea level. In the valley, the river flows along a slight slope of 0.3 - 0.4‰.

The entire valley of the M±tawa is protected by a flood bank that stretches for 31.8 km from Nowy to Sartowice The extant flood bank belongs to the class III facilities and confirms to technical requirements for hydrotechnical structures and their location. The flood bank has the following dimensions and features:

- width of the embankment crown: 3.8 - 5.0 m
- water side slope: 1:2 - 1:3,
- outside slope: 1:1.5 - 1:2,

The embankment rises above the protected area by 3.5 - 7.1m and occasionally 9.2m in relation to the level of the flood alert of 4.1 - 5.9m. A flood bank sluice and a pumping station located in Kończyce are important flood protection facilities.

The land and structures protected against flood:
- farmland 5740 ha
- grassland 2600 ha
- buildings and gardens 200 ha
- orchards 200 ha
- other (waters, wasteland, roads, etc.) 797 ha
9537 ha

- farm buildings and houses 681
- public buildings 34
- railway stations 1
- plastic greenhouses 90
- glass greenhouses 15
- surfaced roads 69 km
- railway tracks 3.5 km
- population 5381
- livestock 10000
- special drainage and irrigation structures 6434 ha
- basic drainage and irrigation facilities
§ rivers and canals 38.8 km
§ flood banks 36.3 km
§ pumping stations 2

III. Historic outline

Since the beginning of colonization of the M±tawa river valley between ¦wiecie and Nowe, settlers had to cope with floods and excess of water. The precise date of colonization of this area is unknown, but we know that the colonization process began long before the Teutonic Knights have been introduced here by Konrad Mazowiecki in the 13th century. According to old chronicles, already in 1498, the Teutonic administrator of the Żuławy M±tewskie estate received a loan of 200 marks for repairs of a broken flood bank.

After the signature of the Toruń peace treaty, which ended the thirteen year war, 1454 - 1466, the M±tawa valley was depopulated, the flood protection works were abandoned and the flood bank destroyed.

The historical materials show that the intensive activities associated with flood protection in the M±tawa valley were resumed in the 16th century, that is, when the area was colonized by the Dutch. The Dutch began to build a flood bank along the Vistula and partially also along the M±tawa. Initially, each community erected their own flood banks. The builders were organized in community flood bank associations - local organizations, which had to cooperate because otherwise their work would not produce desired results. Originally, the embankments were relatively low and the spring water was able to flow above them. The settlers planted willows and poplars to prevent the inflow of ice floes into the valley and in general to protect the land from the rapid current. When the spring water rose, with this system of flood protection, the houses would have been completely flooded, if they had not been located in elevated areas. Since there was no natural rises, the settlers built artificial hillocks for their homesteads. The Dutch were not afraid of water and the flood was not considered a disaster providing it only flooded the lower floor or a cellar. They had devices to transport livestock to the higher floors of a house; people also moved there with supplies of food, fodder, and straw. The water flooded the lower empty rooms causing some damage, which was accepted by farmers. The chronicles of the M±tawa church report that the church building was flooded every year, and the chronicler notes that deposits of slime had to be removed from the church every year; however, this fact seemed to be a standard procedure. Due to the fact that the spring flood deposited fertile silts, farmers had to adapt to this phenomenon, which actually had more positive than negative effects.

In 1855, the flood was particularly severe and the flood banks were broken in numerous places. Water carried away many houses and left them in the Tczewskie meadows 50km away.

Several children perished a result of this terrible disaster. The damages were so severe that and the danger so obvious that the Prussian authorities decided to immediately erect a high embankment, which would completely safeguard the valley against the floods.

In 1854, the government established an obligatory flood bank association, which included all villages of the Sartowicko-Nowska lowland located no higher than 21 feet and 10 inches above the Gudzi±dzki post, which indicated the normal water level in the Vistula, which corresponds to the water level elevation with an occurrence probability of p=1%. A new flood bank was erected and a wooden sluice was constructed at the outlet of the M±tawa to the Vistula. As a result of this project, the hydrographic conditions were supposed to improve. However, it turned out that separating the M±tawa from the Vistula during the high water levels of the latter river was very dangerous. In those periods, the water level of the M±tawa was also very high as a result of the spring melt in the river watershed. Due to the high water level in the Vistula, the excess of water from the M±tawa river had no outlet and overflowed its banks flooding fields and villages. These floods were of a smaller scale, but were much worse. The water stayed on fields longer and did not deposit fertile silts, instead, it acidified the soil. Thus, the effects of the erection of a high flood bank along the Vistula were rather negative. In order to solve this problem, the authorities built flood banks on both sides of M±tawa and allocated separate reservoirs to collect the excessive water. Initially, only the meadows of the village of Morgi functioned as a reservoir, and then also the meadows of Mały Komórsk. The first area covered ca. 250 ha and the second one ca. 1000 ha. The M±tawa river was regulated between 1874 and 1878, and in 1884, the authorities acquired a 18000 marks bucket dredger used for desludging the river. Despite all of these efforts, the M±tawa kept flooding the terrain due to the high levels of water in Vistula as well as lack of gravitational outflow of the M±tawa water. In 1888, a serious spring flood waterlogged the entire district of M±tawa for a long time. This event persuaded the local farmers to build a pumping station. Indeed, in 1
890, they obtained a construction permit and the station was installed on the M±tawa riverbank.

The results proved very beneficial for the residents of the M±tawa district, who were able to cultivate their fields, while other villages were flooded. This success prompted a construction of a large pumping station that would drain the entire valley of Sartowice-Nowe and indeed, the station was completed in 1910. The system was designed to pump out the water from the M±tawa watershed during the high water levels in Vistula and to drain the 9500 ha polder of this valley.

In order to guarantee the valley usability and the proper functioning of its infrastructure, it was necessary to maintain the specific water levels.

Months: XII - II 15.05 m above the sea level
365 cm on the water-level indicator in Grudzi±dz
Months: III - XI 14.25 m above the sea level
305 cm on the water-level indicator in Grudzi±dz

The duration of specific water levels of the Vistula measured by the water-level indicator in Grudzi±dz were calculated and transposed to the outlet of the M±tawa river. According to the results, the required annual, average operation times of the pumping station Kończyce were as follows:

- to maintain the water level at 15.05 m above the sea level - 97 days
- to maintain the water level at 14.25 m above the sea level - 142 days

The pumping station was equipped with three engines with impeller pumps in a single-stage siphon system. The pumps were powered by 250 horsepower steam engines and their rate of delivery equaled 12 - 15 m3/sec.

The fuel consumption was 250 kg of coal per hour per boiler. The pumping station functioned with an unchanged construction and propulsion until 1974. There were two operators and during the operation each boiler was manned by two workers. The maximum number of employees was 7 - 8. The coal was transported from Silesia to Nowy by rail and then by a truck, a tractor, and horses to the pumping station in Kończyce. Daily consumption of the 2nd class coal equaled ca. 10 tons per engine. The fuel consumption varied from year to year depending on station operation time of the station:
- 444 T in 1968
- 205 T in 1969
- 1493 T in 1970

The activities associated with flood protection of the Sartowice-Nowe valley gathered momentum after the Zwi±zek Wałowy (Flood Bank Association) was formed in 1854. Between 1855 and 1909, this organization carried out construction works in the Sartowice-Nowe valley. Their costs were as follows:

1. Flood bank and riverbank reinforcement
1. cash 1592821.00 MK
2. in kind: 1960000 m3 of materials, among other things 630000.00 MK
2. Sluices an auxiliary works 277695.19 MK
3. Regulation of the M±tawa 397488.84 MK
4. Installation of pumps 307062.64 MK
5. Interest and amortization 894275.24 MK
6. Administrative expenses 223307.48 MK
7. Other 110574.03 MK
Total: 4433224.42 MK

In addition to these works, other projects had been completed before 1855, for example, draining canals, whose maintenance was partially carried out by the Flood Bank Association. In some areas, the residents formed local flood bank associations to complete particular tasks and were subsequently disbanded. The cost of the above projects completed by the Flood Bank Association on average equaled ca. 500 marks per 1 ha of the protected area. It was a substantial cost and individual farmers would not be able to pay it at the time or in the present day. Part of the cost was immediately paid from the government subsidies. For example, the pumping station, which cost 307052.64 MK was financed by:

- the state 150000 MK
- provincial government 75000 MK
- local government 37500 MK

which totaled 262500 MK. The remaining amount was covered by a low interest loan. As a result, the interest and amortization fees paid by individual farmers were very small.

There are no historical data that would provide information about the amount of money provided by the government to finance the regulation of the M±tawa and the construction of the flood banks and sluice, but it was probably a large share of the total cost. However, the interested parties also had to contribute a substantial amount since the interest and amortization costs amounted to nearly 900000 marks. On December 31, 1919, the debt was only 278600.30 marks. This debt was reduced as a result of devaluation and in 1926 equaled:

- first loan in marks with the amortization until 1945
after the conversion 27422 zlotys
- second loan in marks with the amortization until the end of 1930
after the conversion 13613 zlotys

The expenses associated with the pumping station operation were very high and vary considerably from year to year. The M±tawa river was dredged every couple of years. This operation was carried out immediately after the acquisition of a dredge and then in 1930, 1931, and 1933. The hours of operation of the pumping station varied every year and depended on the conditions of water flow. In 1921, its operating time was the shortest; the station worked only for 7 days, and consumed 21600 kg of coal. The maximum number of hours of operation between 1910 and 1931 occurred in 1913. In that year, the water was pumped for 164 days and 17 nights, and the coal consumption equaled 517000 kg. In 1931, the total sum of expenses equaled 55450 zlotys. That amount included a considerable fee for dredging the M±tawa. The budgets that do not include dredging the M±tawa are smaller. In 1932, the members of the Flood Bank Association were charged 43000 zlotys.

The administration of the association was run very efficiently; according to the 1931 budget, all annual salaries, including that of the technical and administrative staff cost only 6260 zloty. For example, the annual salary of the association's chief administrator was only 900 zlotys; the engine driver's salary was 1800 zlotys and office costs, 550 zlotys. Thus, the association was able to operate economically, and due to the fact that almost entire loan was paid off, the fee was quite small and in 1932 equaled 10 zlotys per a "normal hectare". The normal hectare was a surface area of one hectare of the 1st class farmland. The fees for farmland of lower classes were calculated in relation to the normal hectare fee. For example, for the 6th class farmland, the owner paid 30% of the 1st class fee, 15% for the 1st class gardens, the same amount for buildings and yards, and 10-20% for pastures. The total amount from 8665 ha calculated according to the above rule totaled 4299.74 zlotys. Thus, the average annual cost of the association membership equaled 5 zlotys per hectare. This was a surprisingly small amount considering the benefits provided by this association. The activities conducted by the Flood Bank Association of the Sartowice-Nowe valley between 1854 and 1974 provide an example of proper operation of a conservation and maintenance public organization. Members of this organization - the users and residents of the region - actively participated in its activities and the role of the state was limited to providing assistance in obtaining subsidies and loans.

IV. Activities related to maintaining technical efficiency of the pumping station Kończyce and other facilities protecting the M±tawa valley.

In addition to maintaining and operating the pumping station and the flood bank sluice, these facilities had to be maintained in order to guarantee their technical efficiency.

1. In 1962 and 1963, the flood bank sluice was renovated based on the documentation prepared by the Spółdzielnia Pracy Dokumentacji i Robót Technicznych (Technical Works and Documentation Cooperative) in Gdańsk. The project included:
- reconstruction of walls and pillars,
- securing the load-bearing sections of the facility with a layer of ferroconcrete,
- spacing as well as crosswise and lengthwise reinforcement of the sluice,
- reinforcement of intermediate and outermost pillars.

2. In 1966, the boiler brickwork underwent emergency renovation based on the expert opinion of the Gdańsk University of Technology.

3. In 1973 and 1974, due to the deteriorating condition of the boilers, which were only conditionally approved for use, one of the steam engines (no. 3) was replaced by an electric one. Primary power supply lines and a transformer station were installed as part of the project. A 300 kW engine, gears and clutches were installed.

4. In 1977, as a result of a positive evaluation of the modernization of pump no. 3, the authorities decided to replace the other steam engines with electric ones. The project was completed in 1978.

5. Another renovation of the flood bank sluice was carried out in 1983 and 1984; it involved:
- chiseling the cracks and filling the openings with bricks with cement mortar,
- repairing the gates,
- installation of a ferroconcrete trough below the outlet and reinforcement of the river bottom with a fascine and stone base.

6. In 1984, the priming funnels of the pumps were replaced because of the advanced corrosion and because it was impossible to obtain vacuum. Other minor repairs were carried out in order to extend the life of the pumping station.

In spite of the completed maintenance and renovation works, the technical condition of the pumping station has been deteriorating. Considering the circumstances, the administrator of the facility made plans for construction of a new pumping station, independently of the above renovation works. As early as 1980, a general plan for draining the entire M±tawa valley was prepared, and in 1982, the preparations for the construction of a new pumping station in Kończyce began.

The new facility with auxiliary buildings was erected between 1993 and 1995. The new pumping station cost 8220 thousand zlotys. It was a modern facility using the most recent technologies and the first application of submersible pump in the country. In 1996, the facility won the 1st degree NOT prize for achievements in technology in the Bydgoski voivodeship. The Minister of Internal Affairs and Administration awarded the designer the 1st degree prize in the field of construction and architecture. The facility's technological, economical, and environmental features were also highly appraised. The application of modern pumping technology reduced the necessary capital investment. Small volumes of the buildings, short completion time, reduced costs, and benefits proven during the flood are the basic merits of this project.

Independently of the mentioned enterprises, the recent years have seen completion of other projects related to flood protection and regulation of the hydrographic conditions. The completed projects include:
- installation of a new flood bank sluice in Kończyce between 1999 and 2000 with the value of 6670 thousand zlotys,
- reconstruction of pumping station Pastwiska with the capacity of 0.66 m3/sec and the value of 495 thousand zlotys.
- regulation of the M±tawa river from 0+650 km to 13+300 km in 2001 and 2002 with the value of 1900 thousand zlotys.
- installation of a weir in the M±tawa river at the 13+300 km in 1996 and 1997 with the value of 520 thousand zlotys.
- special drainage works on the M±tawa - Bratwin I section, which covers 659 ha, completed between 1995 and 1999 with the value of 1900 thousand zlotys.

The above projects consumed a total of 19705 thousand zlotys in capital investment, which is a very large sum considering the limited budget, which has been gradually reduced. Such a concentration of capital was possible due to the non-state funding provided by:
- funds from the National Fund for Environmental Protection and Water Management,
- Social Fund of the Council of Europe with the funds from the central budget,
- funds from the European Investment Bank with the funds from the central budget.

In spite of such an extensive program, not all problems related to the flood protection have been solved. The most urgent projects include:

- further regulation of the M±tawa river from 13+330 km to 30+400 km, with the estimated value of 2100 thousand zlotys.
- modernization and reinforcement of the 16 km section of the flood bank with the unspecified cost due to the lack of a plan.
- installation of 7 polder pumping stations with a total capacity of 8.84 m3/sec draining 4100 ha.

However in addition to the erection of new facilities or the modernization of the extant ones, there is a separate problem of their ongoing maintenance. Since the establishment of the Flood Bank Association in 1854, the maintenance tasks were carried out by its members. The association was supported by the state and local authorities and acquired funds in the form of subsidies or loans. This situation came to an end in 1974, when the Water Laws were enacted. According to these regulations, the hydrographic facilities were divided into basic and special facilities. The basic facilities are facilities and structures that protect the area against floods. In the case of the M±tawa valley, these include:
- flood banks,
- pumping stations,
- flood bank sluices,
- the M±tawa river.

The owner, that is, the state is responsible for the maintenance of these structures.

The annual average maintenance costs (according to the current prices) for the flood protection facilities in the M±tawa valley are as follows:

- maintenance of the flood bank: removal of vegetation and repairs of the banks on the 31.8 km section 349000 zlotys
- maintenance of the pumping station and sluice Kończyce, 252000 zlotys
including the cost of electrical power 223000 zlotys
- maintenance of the 30 km valley section of the M±tawa river 67000 zlotys
- maintenance of the pumping station Pastwiska and the Pastwiska canal 26000 zlotys

Total 694000 zlotys

This total gives us 72 zlotys per 1 ha of the protected area. For many years, the state carried out these tasks satisfactorily. However, in recent years, due to a drastic reduction of funding for the maintenance of the basic flood protection facilities the quality of the maintenance operation decreased. There is a lack of funding for the maintenance of the M±tawa flood banks, which has a negative effect on the hydrographic conditions in the valley, especially in the wet years, for example 2001 and the first half of 2002.

V. Summary and conclusions

The flood-related issues demonstrated in this presentation are based on an example of the northern section of the M±tawa valley located between Sartowice and Nowe and include evaluation, range, and effects of floods, historical outline of coping with floods, and flood protection activities carried out between the 14th century and the present day. The presented problems provoke the following conclusions:

1. The flood is a natural phenomenon and occurs when the flow rate of water from precipitation and melting snow exceeds the river bed capacity. In those cases the river floods the adjacent areas and causes damages.

2. Since the dawn of time, due to presence of fertile soils and easy access to water, people inhabited river valleys, built towns and villages, cultivated land, developed industry and communication routes in river valleys. On the other hand, though, the risk of floods was always the price for comfort of living in river valleys. The presented effects of both the historical and recent (1997 and 2001) floods prove that this phenomenon is of tremendous importance for the region. Underestimating floods is responsible for considerable damages including losses in men and livestock and enormous material losses in crops and the regional infrastructure.

3. People have been trying to cope with this phenomenon for centuries. Flood protection is necessary and is associated with erection of appropriate facilities and structures, such as:
- flood banks,
- pumping stations,
- valley canals and rivers.

The Dutch settlers rendered considerable services to the alleviation of this problem. In the M±tawa valley, they provided a model for coping with floods and minimizing the damages.

4. In light of the recent catastrophic floods that occurred in 1997 and 2001, the flood protection activities in Poland should be intensified and include:
- installation of additional facilities,
- modernization of the extant facilities,
and the proper maintenance of existing devices, whose condition has been deteriorating due to reductions in state funding. In addition to the state authorities, the local government, institutions, companies, and people threatened with flooding should get involved in activities related to flood protection.

Improvements in organizational systems and legislature should in effect ensure security of the land, people, and property threatened by floods.

Literature

1. Zdzisław Ludkiewicz; Osady Holenderskie; Toruń, 1934
2. mgr inż. Marian Złonkiewicz; Stacja pomp w Kończynach z zatapialnymi pompami ¶migłowymi; Wiadomo¶ci melioracyjne i ł±karskie, no. 3, 1997
3. mgr inż. Marian Złonkiewicz; Działania organizacyjno - techniczne służb przeciwpowodziowych w czasie awarii lub katastrofy obiektu hydrotechnicznego (na przykładzie polderu chronionego); pub. of the Główny Komitet Przeciwpowodziowy; Krajowe szkolenie - Ochrona przed powodzi±; Jurata, May, 2002
4. Kujawsko - Pomorski Zarz±d Melioracji i Urz±dzeń Wodnych we Włocławku Oddział Rejonowy w Bydgoszczy (Bydgoszcz Regional Branch of the Pomeranian Management of Water and Drainage Facilities) in Włocławek; Statistical and Informational Materials


Home | Introduction | Download e-book | Conference 2001 | Special thanks | The note of law | Contact
Articles: Poland | Małopolska | Mazowsze | Ziemia Łęczycka | Żuławy | Nizina Sartowicko-Nowska | Ziemia Kwidzyńska | Ziemia Walichnowska | Ziemia Sieradzka | Ziemia Wieluńska

Copyright 2005 © jerzyszalygin@wp.pl