THE FAULTY SOLUTIONS OF ANTI- FLOOD MEASURES

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1 EkoFlood 2003, Warszawa Stanisław Ostaficzuk 1) & Marek Ostrowski 2) THE FAULTY SOLUTIONS OF ANTI- FLOOD MEASURES 1) Chair of Fundamental Geology Faculty of Earth Sciences University of Silesia, Katowice 2) Autonomy Dept. of Image Information SCI-ART Warsaw, PL

2 In most cases, man have a negative impact on natural disaster hazard The most typical and well known man related causes of danger are: 1 - Covering of flood-prone terraces with railway and highway embankments; 2 - Leaving too narrow openings under bridges; 3 - Narrow-canalling of streams and river channels without enough safety margin for high water flow; 4 - Wrong sitting of engineering constructions, due to wrong location, poor foundation, wrong design, poor construction work; 5 - Forming bottlenecks for flood waters by wrongly placed constructions; 6 - Settling compounds, factories and farm buildings on flood prone terraces; 7 - Reducing of natural terrain capabilities for rain water infiltration, 8 - Deforestation of, especially, high-grade slopes.

3 Location of the study area - Europe, Poland POLAND KŁODZKO BASIN CARPATHIANS (After Z. Perski 2000)

4 Location of the study areas - Poland: - Kłodzko Basin, Sudetes, - Carpathians EcoFlood 2003, Warszawa WARSZAWA (After Z. Perski 2000)

5 Preamble Poland is plagued by disastrous floods, which are very frequent and damaging especially in mountains. Less often, the flooded mountain rivers gather strength in the fore-mountain areas, causing damage to villages, towns, and occasionally big cities in Lowlands. That is due to a lack of space for temporary retention of excess waters. Ironically, Poland is strongly endangered by deficit of fresh water (see the UNO Reports). That, should be a favorable situation for custom development of proper anti-flood engineering measures. Unfortunately, very often it is not.

6 And here are some samples (Geological Map by PGI)

7 A factory sited inside the riverbreak-away gorge N.b.: It would be a good place for a 40 m high water dam and a hydro power station (Photos by S.Ostaficzuk 1998)

8 Solid stone bridge (red arrow) is obstructing free outflow of flood waters, thus contributes to worsening of flood damages upstream (Photo M. Ostrowski 2000) EcoFlood 2003 Warszawa

9 The solid bridge in Bardo has withstand load of flood waters in 1997 and caused overflow of terrains upstream (Photo Ostaficzuk, 1998)

10 EcoFlood 2003, Warszawa The Pilce case - carelessly damaged alluvial plains (subject to another presentation) (Photo Ostrowski 2000)

11 Spontaneous bypass - village Pilce (general view downstream) A lack of protective wall, dashed line, at the brink of a gravel pit, made the village Pilce, and the access road, open to the strong backward erosion (red arrow) (Photo Ostaficzuk, 1998)

12 Spontaneous, self-canalized wild bypass (green arrow), and backward erosion; close-up view (Photo Ostaficzuk, 1998)

13 Selection of example results of faulty engineering

14 (Photo Ostaficzuk, 1998)

15 Bridge damaged by flood water due to poor, too shallow foundation (river flows to the left) EcoFlood 2003, Warszawa (Photo Ostaficzuk, 1998)

16 Left hand side bridge-head destroyed due to poor foundation EcoFlood 2003, Warszawa (Photo Ostaficzuk, 1998)

17 Bridge destroyed by flood water due to poor construction (view downstream) EcoFlood 2003, Warszawa (Photo Ostaficzuk, 1998)

18 Flood damages due to poor road maintenance - Bystrzyca Dusznicka (looking upstream) EcoFlood 2003, Warszawa (Photo Ostaficzuk, 1998)

19 Flood damages to road constructed right in the stream channel (view downstream) (Photo Ostaficzuk, 1998)

20 Closely related to flood events in mountains are landslides.

21 Landslide prone areas in the upper catches of the river Sola in Carpathians (After Z. Perski 2000)

22 Carpathians dilemma: landslide or, flood (Photo Ostrowski 2000)

23 Selection of example results of faulty location and the engineering negligence

24 The damaged property at the bridge- choke outlet EcoFlood 2003, Warszawa (Photo Ostaficzuk, 1998)

25 River Nysa Kłodzka, Klodzko downtown; no room for bypass (Photo Ostrowski 2000) EcoFlood 2003, Warszawa 1

26 Artificial bottleneck Kłodzko; red arrow shows flood water level in July, 1997 EcoFlood 2003, Warszawa (Photo Ostaficzuk, 1998)

27 Upstream off bottleneck Kłodzko; red arrow points on a maximum flood water level in July 1997 EcoFlood 2003, Warszawa (Photo Ostaficzuk, 1998)

28 The Kłodzko city downtown 1998 (flood marks on walls after the 1997 flood) (Photo Ostaficzuk, 1998)

29 After the cloudburst (Photo Ostaficzuk, 1998) EcoFlood 2003, Warszawa

30 House standing in a front of a bottleneck was partially destroyed by flood water-jet EcoFlood 2003, Warszawa (Photo Ostaficzuk, 1998)

31 No comments (Photo Ostaficzuk, 1998, 2001) (The same house immediately after the flood and three years later)

32 Right in the middle of an intermittent stream EcoFlood 2003, Warszawa (Photo Ostaficzuk, 1998)

33 The ad hoc actions are becoming customary (Photo Ostrowski 2000)

34 Just patching it up (Photo M. Ostrowski 2000) EcoFlood 2003, Warszawa

35 (Photo Ostaficzuk, 1998)

36 The perfect place... The negligence? EcoFlood 2003, Warszawa Ostaficzuk, 2003 (By S.Ostaficzuk 2003)

37 The only positive solution recorded so far Carpathians EcoFlood 2003, Warszawa (Photo Ostaficzuk, 2000)

38 For many reasons in most cases it is too late for resettling people from flood prone areas. Instead, complex hazard mitigation actions may be effective and possibly in high agreement with the environmental needs. These will be oriented on two goals: - One is the prevention against further worsening of existing stateof-the-art of the flood prone areas by intensifying retention in the uppermost catches of the drainage basin, - The other is planning of new protective constructions and other safety measures on-site.

39 The most important new protective constructions and other safety measures are proposed: 1 - Forestation wherever applicable, 2 - Construction of reversed wells high in the water catchment area, 3 - Construction of numerous dry reservoirs for catching debris and high water immediately after heavy rainfall, 4 - Construction of reserve outflow canals, tunnels, reservoirs, 5 - Multistage system of outflow control within the high order catchment areas, 6 - Adaptation (instead of re-cultivation) of selected abandoned mine pits for temporary retention of flood waters 7 - Legislative regulations favorable for the all above listed actions

40 In order to resisting short time high water flow: Existing road or railway embankments on flood prone terraces shall be replaced by estacades or lowered of selected sections. Bypass canals and/or tunnels shall be built or existing construction adapted for securing of fast spill of flood or cloudburst waters; Wherever applicable, embankments of canals shall be tightly walled, with communication openings secured by steel gates; The windows, doors, and other openings facing the canals shall be mason-walled or secured with steel doors;

41 Literature Dubicki A., Słota H. & Zieliński J. (Eds.), 1999: Monografia powodzi lipiec 1997; dorzecze Odry. IMGW. Warszawa ESRIN, 1999: ERS SAR images (tandem mission) from Klodzko; SLCI format. Gardner-Outlaw T., Engelman R. 1997: Sustaining Water, Easing Scarcity; 2-nd ed. Population Action Intrn. Tab. p Grela J., Słota H. & Zieliński J. (Eds.), 1999: Monografia powodzi lipiec 1997; dorzecze Wisły. IMGW. Warszawa Kizny T. & Błahut-Biegańska D. (Eds.), 1998: Żywioł; powódź we Wrocławiu i na Dolnym Śląsku; lipiec PWN.Warszawa-Wrocław Krzyszkowski D., Przybylski B. i Badura J., 1999: The Pleistocene stratigraphy and neotectonic evolution of terraces of the Nysa Kłodzka (Glatzer Neisse) river valley, Sudeten, SW Poland. Terrestrische Quartergeologie, Koeln Ostaficzuk S. (Ed.) 2000: Dynamiczna ocena i prognoza geologicznych zagrozen wywolanych powodzia [Dynamic assessment, and geological prognoses of flood hazards]. IGSMiE (PAN). Krakow. 250 pp. (in Polish, English captions). Sustaining Water; Population and the Future of Renewable Water Supplies. Washington DC.