1. 10 th Eco-Junior-Expert Project Human activity and Its impact on the environment Group III Flood Control Measures

2. Names and nations Student from Poland: Zawistowski Aleksy, Wiecheć Bartlomiej, Dziadek Michal, Chrapek Pawel Student from Austria: Auer Theresa, Schlager David, Taschl Ines Student from Czech Republic: Formánková Andrea, Háva Lukáš, Ištok Tomáš, Poborská Anna, Sokolík Jakub, Šimánková Eva, Urbanová Zuzana, Krebsová Lenka, Hruška Martin, Nováková Tereza, Novotná Dagmar, Novotná Tereza Student from Hungary: Nagy Alex, Mészáros Richárd, Nagy Gábor, Kóder Kinga

3. Task Measuring the flow rate of different rivers The Lužnice River The Nežárka River The Blatský Brook

4. Floods

5. Flood control measures As a prevention against floods are used river channel reconstruction and the environs. Two alternative methods exist: mobile and fixed barrier. Dry polder Krkavec Polder is dry reservoir, which retains high water. Two variants of the construction of dry polder are decided.

6. Variant 1 Culmination flowDecreasing of the effect Twenty years flood Q 20 = 189 m3/s→ 51 % Fifty years flood Q 50 = 253 m3/s→ 55% One hundred years flood Q 100 = 315 m3/s → 55%

7. Variant 2 Culmination flowDecreasing of the effect Twenty years flood Q 20 = 189 m3/s→ 24 % Fifty years flood Q 50 = 253 m3/s→ 14% One hundred years flood Q 100 = 315 m3/s → 9%

8. Calculation of revolutions in time Calculation of the speed of the water flow Making profiles of the rivers Calculation of data

9. How we measured Special instrument: current meter Method: measure width of the river Allocation Measure flow rate Calculation

11. Results of the Nežárka river Profile of the river  Rotations per minute 

12. Results of the Blatský Brook 10 cm20 cm30 cm 168 x 22122x 3521 Profile of the river  Rotations per minute 

13. Lužnice: Profile of the river

14. Lužnice: Rotations per minute Measuring Point 123456789 20 cm000043300 40 cm054565010 60 cm0131011129220 80 cm088055670 100 cmxxx107405x 120cmxxxx10866x 140 cmxxxxx981x 160cmxxxxxx10xx 180cmxxxxxx11xx 200 cmxxxxxx10xx

15. Speed of the Blatský Brook Vertical post number Average speed in the vertical point m/s 1. 1m from left bank0,2705 2. 2m from left bank0,0908 3. 3m from left bank0,0179

16. Vertical post number Average speed in the vertical point m/s 1. 2m from right bank0,1263 2. 4m from right bank0,5582 3. 6m from right bank0,4009 4. 8m from right bank 0,52165 5. 10m from right bank0,6989 6. 12m from right bank0,7316 7. 14m from right bank0,5024 8. 16m from rigth bank0,3567 Speed of the Nežárka river

17. Speed of the Lužnice river Vertical post number Average speed in the vertical point 1. 2m from left bank0 2. 4m from left bank0,023219 3. 6m from left bank0,0232 4. 8m from left bank0,0219 5. 10m from left bank0,0309 6. 12m from left bank0,0409 7. 14m from left bank0,0256 8. 16m from left bank0,01889 9. 18m from left bank0

18. Comparison: our results with the results from CHMI (= Czech Hydrometeorogical Institute) Location of measurementFlow rate (m 3.s -1 )Data of CHMI the Lužnice River 0,5620,984 the Nežárka River2,732,84 the Blatský Brook0,103x

19. Summary Our results are coresponding with average rates meassured by CHMI. In 2002, the high water striked also Veselí nad Lužnicí and this flood was the most severe flood recorded in the history. During the floods 415 houses were flooded (that is, 40 % of the area of this city was flooded). In Veselí nad Lužnicí the floods repeated in 2006.

20. Flood control measures In Veselí nad Lužnicí flood control measures will be implemented in 2009 and this project will be finished in 2011. As a prevention against floods are used river channel reconstruction and the environs. Two alternative methods exist:mobile and fixed barrier. The mobile barriers are installed just before the flood starts. The mobile barriers are constructed from sand-bags and mobile dikes. The fixed barriers are firmly connected to bedrock.

21. Thank you for your attention…