Dealing with floods in Cologne - Flood Management: Routine ... · Hochwasserschutzzentrale Köln Dipl.-Geogr. Agnieszka Czypull Willy-Brandt-Platz 2 / 50679 Köln (Stadthaus Deutz)

Hochwasserschutzzentrale Köln

Dipl.-Geogr. Agnieszka Czypull

Willy-Brandt-Platz 2 / 50679 Köln

(Stadthaus Deutz)

+ 49 (0)221 – 221 23162

[email protected]

Dealing with floods in Cologne- Flood Management: Routine or (new) challenge?

Dealing with floods in Cologne

Dipl.-Geogr. Agnieszka Czypull StEB / HSZ 2

Outline

Part one: Some facts about the Rhine

Part two: Organisation and responsibility

Part three: Flood stages, forecast and warnings

Part four: Practical examples



Part one: Some facts about the Rhine



one – two – three - four

CologneCatchment and discharge


Map of

Germany



» catchment: ca. 200,000 km²» length: 1,230 km » the Rhine passes 4 countries

(Switzerland, Austria, Germany and the Netherlands)

» the Rhine is a border river for Liechtenstein and France

» also impact from: Italia, Luxemburg and Belgium

» in Germany: 4 federal states




Facts for the Cologne river gauge (KP)

» 0.80 m low water / drought 2003» 3.21 m average water-level» 5.75 m first overflow» 6.20 m flood mark I» 8.30 m flood mark II» 10.63 m flood in 1993 » 10.69 m flood in 1995 + 1926




Return periods (1901-2011)

» 7.50 m KP 1» 8.00 m KP 2» 8.50 m KP 3» 9.00 m KP 4 - 5» 9.50 m KP 8 - 10» 10.00 m KP 15 – 20 » 10.70 m KP 40 – 50» 11.30 m KP 100» 11.90 m KP 200» 12.50 m KP 500




» 10.70 m (1995 flood) (old level: 10.00 m) Porz-Zündorf

» 11.30 m (100-years flood) areas in southern Cologne and the Altstadt (Old Town), but also Porz-Langel and Westhoven

» 11.90 m (200-years flood)areas in northern Cologne and right river bank

Protection levels




How does the danger look like?

» 9.50 m KP» 530 affected people in

unprotected area (blue marking)

» 6,300 people endangered in protected area (yellow/red marking)




» 10.70 m KP» 2,100 / 37,000




» 11.30 m KP» 2,300 / 76,000




» 11.90 m KP» 38,000 / 100,000




» 12.50 m KP» 205,000




Part two: Organisation and responsibility



Who is responsible?

Cologne has entrusted the Cologne drainage and flood service company(StEB) with the responsibility for the flood protection, flood management and flood prevention

The Flood Protection Centre of Cologne (HSZ) is a department of the StEB




What are the resposibilities of the (HSZ)?

Fields of work of the HSZ» water-level forecast» enhancing the public awareness to floods» risk communication» flood prepardness» information centre for floods and

groundwater hazards» advancing the flood management» alert and operation schedule / coordination» schooling of the staff» national and international cooperation in

flood protectionone – two – three - four

In case of flood» flood forecast» representative in charge for the

entire flood stuff» warning of the public» coordination of the flood protection

measures» journalisation of the flood event



> 7.00 m KP

Who does participate in case of flood?




» HSZ coordinates the entire flood measures

» but every organisation acts in own responsibility

» number and scope of the flood measures always depend on the water-level and the current situation




What else does the StEB do?

» wastewater disposal

» maintenance of surface water

» flood protection (structural + mobile flood protection, flood management and risk prevention)


Cologne drainage and flood service company



Part three: Flood stages, forecast and warnings



Flood stages

» flood stage 1: ≥ 4.50 m KP• first overflows / first measures (sewere network)

» flood stage 2: ≥ 5.50 m KP• „small“ Flood Protection Centre (klHSZ) / flooded paths

and parking areas» flood stage 3: ≥ 6.50 m KP

• first housing areas are prone» flood stage 4: ≥ 7.00 m KP

• big risk of flooding in several city-districts / mobile elements / „big“ Flood Protection Centre (grHSZ)

» flood stage 5: > 10.70 m KP• major catastrophic event / fire brigade overtakes the control




Forecast

» water-level depends on meteorogical data (e.g. temperature)

» weather three days ahead» rainfalls have to come down




What does happen when the rain has occured?

» HSZ does not have any own forecast model (mathematical or physical)

» What do we do?




Monitoring and expert knowledge


» offical forecasts for the water-levels of the Rhine: flood registration office RLP



Monitoring and expert knowledge

» problem: water-levels often too low, too high, forecasts too late

» first measures in Cologne: 4.50 m KP

» telephone request of 24 gauges in certain intervalls

» aditionally: overview of gauges (internet)




Expert knowledge and empirical values

» from Maxau to Cologne: 48 hours / calculation of flow velocity

» influences of the tributaries (e.g. Mosel)

» other influences: e.g. ground conditions (waterlogged, frozen)




precisely estimation of the water-level for Cologne in order to warn the citizens and arrange the flood protection

measures (challenge: the right time, not too early but also not too late)

estimations for Cologne are based on personal experience and knowledge (estimations of the StEB/HSZ only and only for Cologne) !




Warnings

development of the Rhine (general)

water-level in Cologne at 6 am

tributaries

future prospect

measures (flood measures)

HSZone – two – three - four

» „flood messages“ send over Outlook

» all involved organisations and departments / persons

» aditionally: „Radio Köln“ local radio station to inform the population

measures are done in own responsibility



Other ways of information


» homepage (www.steb-koeln.de/hochwasser)

» telephone / answering machine (+49 (0)221 221 26161)

» newspapers» TV» citizens‘ groups

» several ways to inform

» own responsibility



Interest in information

» citizens of Cologne (especially those, who are living near the river)

» several council departments » people who carry on

• infrastructue facilities• industries

» mainly: Cologne, but a lot of inquiries from the neighbour-cities

» too many phone-calls Citizens‘ Phone or even CallCentre of Cologne




Is there a need for further information?» in case of flood:

• other ways of information possible: e.g. SMS or flood-apps

• for Cologne the existing ways are enough

• should not be forgotten: cost-benefit factors

» in case of low water-levels:• regulary information of the population is needed • rising of awareness is the best way to prepair the people for floods• possibilities to inform the people: homepage, telephone (answering

machine), flood-exibitions, leaflets, guided tours, flood-information-performances





Part four: Practical examples



Flood exercises – What for?

» in order to guarantee a smooth process of all taken measures» to avoid errors / to illustrate weak points (planning or execution)

» to improve the flood management




Protection measures in case of flood (in Cologne)

» 3,000 measures in sewere network (underground flood protection measueres)

» building up and guarding of 10.5 km mobile flood walls

» 31 pumping stations» 500 traffic management measures» local protection measures

(e.g. window or door catches)

» closing of tunnels» building up of foot-bridges» ferry-boat services




Flood exercise – September 2009

» What has been done?» command post exercise

including all involved departments

» building up of mobile protection walls (3 km) with regard to a rising water-level




Screenplay - examples

» inflow of groundwater into a basement garage

» a ship drag oneself away from the Rheinauhafen (habour) and drift guideless on the Rhine

» a couple of guys try to steal parts of the mobile wall

reaction




Wasserstand m KP

3

4

5

6

7

8

9

10

11

12

6.9.096:00

6.9.0918:00

7.9.096:00

7.9.0918:00

8.9.096:00

8.9.0918:00

9.9.096:00

9.9.0918:00

10.9.096:00

10.9.0918:00

11.9.096:00

11.9.0918:00

12.9.096:00

12.9.0918:00

13.9.096:00

13.9.0918:00

Wasserstand m KP

» Federal Insitute of Hydrography calculated a flood scenario

» the scenario started previously before the active exercise with a water-level of 4.50 m KP

» in the morning of the 11.9. the water-level crossed the 7.50 m KP mark» the maximum value of 11.25 m KP was reached on the 12.9. (100-year

flood)

The scenario –September 2009



» successful simulation of flood prevention by a fast rising water-level

» in many parts: goals have been reached» but also room for improvements

• mobile wall wasn‘t completely installed in the given time

• scenario was well known weeks before• logistical concept• more exercises and courses of instruction• more attention to operational safety• more security is necessary to avoid

demolition and vandalism• local information flow needs to be improved• a higher sensitisation of all authorities is necessary

Result of the exercise





Flood event in January 2011

1. peak8.91 m KP

2. peak8.71 m KP

» first „higher“ event after completion of new flood protection measures » reasons: rainfall and snow melting in the catchment of the Rhine» event: from 7th to 24th of January» „flood message“ just one day before rising of water-level = 16 cm/h




Done actions

» measures underground: 21 pumping stations, over 400 flood valves were activated

» 1.3 km of mobile protection walls (only 10 % of the total)

• mainly in the south and centre of Cologne

» ferry-boat service» flood brigdges (footbridges)



Citizens Phone / Citizens Advice Centremost phone calls on Sunday: 1,046

in total: 6,373 phone calls (from 6.-18.1.)




» How is the situation?» When does the water-level reach

the peak?» Is my house prone by ground-

water?» Where can I get sand-backs from?

FAQ

Dipl.-Geogr. Agnieszka Czypull



Visits on homepage

most visits on homepage on Sunday: 69,686

in total: 409,050 visits on homepage (from 6.-18.1.)




Employment of staff and costs

» 150 persons were constantly on duty» 250 persons at peak periods» about 542,000 € overall costs

• security patrols (guarding of mobile flood walls)

• manpower costs (logisticians, compensitions of outlay, eg. THW Federal Agency of Technical Relief)




Summary of flood event

» all taken protection measures were realized problem-free

» some communication problems» needed futher attention

• clearance programm• sandbags• reponsibility in taking measures against upcoming

groudwater

» the security patrols and the logisitics were most expensive solved (more or less)





Conclusion


Flood Management: Routine or (new) challenge?

» Why routine?• plans of action are

prepared before the flood event (e.g. during the summer)

• in general methods of operating / ways of working are well known

• schoolings are hold before the flood season

» Why (new) challenge?• weather development is

often uncertain• personnel matters

(retirement, holiday, illness)

• new weak spots• new exit criteria

every flood event is different



Thank you for your attention

Documents

Dealing with floods in Cologne - Flood Management: Routine ... · Hochwasserschutzzentrale Köln Dipl.-Geogr. Agnieszka Czypull Willy-Brandt-Platz 2 / 50679 Köln (Stadthaus Deutz)