Onno Bokhove , Tom Kent , Henk de Poot and Wout Zweersamttk/files/WetropolisposterEGU2019.pdfOnno...
1
Galton boards: steel balls travel down and land in 1 of 4 columns with at each junc8on a 50% chance of ball going le= or right. Galton boards randomly determine: (i) rainfall amount (columns: 1s, 2s, 4s, or 9s) and (ii) rainfall loca8on (columns: lake/reservoir, moor & reservoir, moor, or no rainfall). Probability asymmetric Galton board: (3,7,5,1)/16. Plan view: Wetropolis: models for educa8on & water-management of floods and droughts Onno Bokhove 1 , Tom Kent 1 , Henk de Poot 2 and Wout Zweers 3 1 School of Mathema8cs, University of Leeds, Leeds, UK; 2 Nobis & 3 Wowlab, Enschede, The Netherlands “Wetropolis: making tangible, interac8ve models for educa8on & policy” is an EFRO RD consor8um (EU fund for regional development), led by Nobis, Dr Henk de Poot, [email protected] References Educa8on & water-management Mathema8cs of extreme rainfall/flood demonstrator Wetropolis interac8ve flood demonstrator is based on a mathema8cal design and visualises how extreme rainfall events can cause extreme river-flood events in a dynamic, conceptual and scaled table-top set-up. Galton boards are used to model different rainfall scenarios over the course of a Wetropolis day (wd=10 seconds) and extreme flooding in a city by rainfall on the current and previous days, as in the real world [1]. Overview, modelled a=er Leeds’ Boxing Day flood 2015 (1:300yr return- period event): • 1:100 sloped river bed; Wetropolis day 10s; upstream inflow; with canal, reservoir/lake & porous groundwater moor draining into river; • chance of rare flood event in city a=er 90% rainfall (9s/wd) is (1/16)x(7/16)=7/256 with a (256/7)x10s=6:06min return period. Wetropolis is designed to flood (right) under extreme rainfall (9s/wd) in moor & reservoir; two consecu8ve wd’s of extreme rainfall lead to a chance of (7/256) 2 <1%; cf. Boxing-Day flood 2015, see; hkps://youtube.com/watch? v=N4Sp5gHXcz4 Droughts: to visualise drought for the 1/16 th route of a dry day, we use the outcome of the first Galton board (not used without rainfall) a=er 2 pins with (3,1)/4 probability. For the 1/4-case, we enforce drought for 4 days, visualised by a drinkwater pipe from the moor falling dry: no water supply! New proba- bili8es then adjust to: (12,28,20,3,4)/67 for rainfall in reservoir, moor & reser- voir, moor, no rain on single day & no rain for 4 days. Drought return period: 67x10s=11:10min. New flooding return period: (16x67/28)x10s=6:23min. Modular design: we are currently making a Wetropolis NFM demonstrator with • par8cipant-built leaky dams in oasis- landscape; and, • river-bed inserts of different roughness (“trees, cement, gravel”). NFM = Natural Flood Management. Promote acDve thinking about different scenarios of flood/drought mi8ga- 8on: Wetropolis is useful precursor in crea8on [2] of water-management solu8ons; also enhances ci8zens’ par8cipa8on. Wetropolis led to flood- excess-volume based cost- effec8veness analysis, e.g., River Brague flood 2015, France [3]:
Transcript of Onno Bokhove , Tom Kent , Henk de Poot and Wout Zweersamttk/files/WetropolisposterEGU2019.pdfOnno...
Galton boards: steel balls travel down and land in 1 of 4columnswithateachjunc8ona50%chanceofballgoingle=orright. Galton boards randomly determine: (i) rainfall amount(columns: 1s, 2s, 4s, or 9s) and (ii) rainfall loca8on (columns:lake/reservoir, moor & reservoir, moor, or no rainfall).ProbabilityasymmetricGaltonboard:(3,7,5,1)/16.Planview:
Wetropolis:modelsforeduca8on&water-managementoffloodsanddroughtsOnnoBokhove1,TomKent1,HenkdePoot2andWoutZweers3
1SchoolofMathema8cs,UniversityofLeeds,Leeds,UK;2Nobis&3Wowlab,Enschede,TheNetherlands
“Wetropolis:makingtangible,interac8vemodelsforeduca8on&policy”isanEFRORDconsor8um(EUfundforregionaldevelopment),ledbyNobis,DrHenkdePoot,[email protected] References
Educa8on&water-managementMathema8csofextremerainfall/flooddemonstrator
Wetropolis interac8ve flood demonstrator is based on amathema8cal design and visualises how extreme rainfall events cancauseextremeriver-floodeventsinadynamic,conceptualandscaledtable-topset-up.GaltonboardsareusedtomodeldifferentrainfallscenariosoverthecourseofaWetropolisday(wd=10seconds)andextremefloodinginacitybyrainfallonthecurrentandpreviousdays,asintherealworld[1].
Overview,modelleda=erLeeds’BoxingDayflood2015(1:300yrreturn-periodevent):• 1:100 sloped river bed;Wetropolis day 10s; upstream inflow;with
canal,reservoir/lake&porousgroundwatermoordrainingintoriver;• chance of rare flood event in city a=er 90% rainfall (9s/wd) is
(1/16)x(7/16)=7/256witha(256/7)x10s=6:06minreturnperiod.
Wetropolis isdesigned toflood ( r i g h t ) u n d e rextreme rainfall (9s/wd)in moor & reservoir; twoconsecu8ve wd ’ s o fextremerainfall leadtoachance of (7/256)2 <1%;cf.Boxing-Dayflood2015,see; hkps://youtube.com/watch?v=N4Sp5gHXcz4
Droughts:tovisualisedroughtforthe1/16throuteofadryday,weusetheoutcomeofthefirstGaltonboard(notusedwithoutrainfall)a=er2pinswith(3,1)/4probability.Forthe1/4-case,weenforcedroughtfor4days,visualisedbyadrinkwaterpipefromthemoorfallingdry:nowatersupply!Newproba-bili8esthenadjustto:(12,28,20,3,4)/67forrainfallinreservoir,moor&reser-voir,moor,norainonsingleday&norainfor4days.Droughtreturnperiod:67x10s=11:10min.Newfloodingreturnperiod:(16x67/28)x10s=6:23min.
Modulardesign:wearecurrentlymakingaWetropolisNFMdemonstratorwith• par8cipant-built
leakydamsinoasis-landscape;and,
• river-bedinsertsofdifferentroughness(“trees,cement,gravel”).
NFM=NaturalFloodManagement.
PromoteacDvethinkingaboutdifferentscenariosofflood/droughtmi8ga-8on:Wetropolisisusefulprecursorincrea8on[2]ofwater-management
solu8ons;alsoenhancesci8zens’par8cipa8on.
Wetropolisledtoflood-excess-volumebasedcost-
effec8venessanalysis,e.g.,RiverBragueflood
2015,France[3]:
