DhakaCity:ThePresentandtheFutureFocusingonEasternDhaka

SMMahbuburRahmanDirector,WRP,IWM

  Morepeoplelivinginurbanareas  Expansionofurbanareas  Morepeopleandassetsvenerabletourbanflood

.

0

20

40

60

80

100

120

140

Rural Urban

Pop

ulat

io, m

illio

n

Tongi K. Tu

rag

R.

Tongi Bazar

Mirpur

Banani

Narayanganj

Pagla

Shimrail

Rupganj

Moghul period British period Pakistan period

Evolu&onofDhakaCity

Bangladesh period 1990

2025

CityExpansion

Present Presentarea: 360sqkmProjectedareain2025: >1500sqkm

PresentpopulaOon: 14.0millProjectedpopulaOonin2025:>25mill

Naturaldrains-60yearsback

Naturaldrainsintervened

DhakaDrainageSystem

Large-scaleUrbaniza&on

Socio-economicchanges

Totalarea:160km2

WestDhaka:136km2EasternDhaka:124km2

Bothprotectedandunprotectedpart

Floods in

Dhaka City

§  River Flood §  Urban Flood

WaterLogging&DrainageCongesOonin

DhakaCity

14loca&onsinwesternDhakaexperiencewaterlogging

Inundation Map of Dhaka in’88 & ‘98 floods

Area of Inundation:

242 km2

Area of Inundation:

168 km2

River Flood 2004 (July 21 – August 10)

Inundated Area 40%

Inundated Area

Baridhara

Gulshan

Rainfall in September 2004 in mm

5 days Cumulative Rainfall in mm

Average Monthly Rainfall in September 11th Sept

29

600

297

12th Sept

156

13th Sept

341

14th Sept

23

15th Sept

51

Urban Flood 2004 (September 13 to 16 )

Motijheel

32,000,000

26,000,000

22,000,000

14,000,000

PopulaOonProjecOonofDhaka

LandusechangetrendsinDhakacity1991–2008

Source:J.LifeEarthSci.,Vol.6:81-89,2011ISSN1990-4827

UrbanGrowthModelling

UrbanGrowthModelling

Ave.LandpricemillionTk./sqm 0.009 0.02 0.04

Ave.mainroadwidth,m 16 23 31

Ave.accessroadwidth,m 2 3 5

Ave.Dura&onofwaterlogging,hr

17 6 3

Lowpricedland

Mediumpricedland

Highpricedland

BUETStudy,2005

LandpricehiketrendinDhakacity1990–2010

Source:Sta5s5calyearbook,BBS

NoraiK.

Badda

AZabnagar

Bashundhara

MadaniAve.

NoraiK.

Badda

AZabnagar

Bashundhara

Outerringroad129km

Innerringroad73km

Middleringroad108km

MRT

BRT

ConceptualStructurePlanofRDP-RAJUK

StrategicTransportPlanbyDTCA|MoR&B

Abdullahpur

Azampur

Ashkona

Kuril

JamunaF-Park

MadaniAve

Badda

AdabNagar

DhakaCircularRoute

MRT

East-WestPrimaryRoad

North-SouthPrimaryRoad

DhakaEasternBypassProjectBWDB|RHD|BRTermukhAbdullahpur

Purbachal

Demra

Kuril-Purbachal

Expresshighway

MadaniAvenue

24kmFloodEmbankment,FourLaneHighway,flyover&ElevatedRailway

83kmKhal&DrainageChannelImprovement

VeryUnevenPopulaOonDensity

The densely populated and morewestern urbanized area is protectedfrom river flood. Unprotected easternarea is frequently flooded by adjacentriver. There is lack of propermaintenance in the protected area.His&rcaldatashowstheextremeeventsaremorefrequentinrecent&mes

30-yrrainfalleventwithoutCCwillbeequivalentto10-yrevent

underB1scenario

WhichisascenariooflessCCimpactandecologicallyfriendly.

ImpactofA1FIismuchmore

pronounced

ExistingSituation

Resilience measures For extreme rainfall event, the drainage system of protected part of the city has to use pumps and proper maintenance also plays an important role. Several structural measures are required for flood mitigation in the unprotected part, land-use zoning and enforcement is also required to make it resilient.

2004

AdaptationMeasures

StructuralIntervenOonsasAdapOveMeasures

  Boxdrainageculverts

  FloodEmbankment

  Pumphouses

Constrained(HighGrowth)WithAdaptation2050

ConstrainedHighGrowth2050

  NofloodEmbankment

  Landfillingforrealestatedevelopmentallowedundercertaincondi&ons

TotalCostofStructuralMeasures:Tk.12,000,000,000~

USD1.5billion

CostofAdaptaOon:USD75million

0

5

10

15

20

25

BAU(MediumGrowth)2030

Constrained(HighGrowth)withAdaptation 2030

BAU(MediumGrowth)2050

Constrained(HighGrowth)withAdaptation 2050

Damage(m

illionBD

T)

ExpectedAnnualDamage

208

6051

CostofAdaptationMeasures(MillionBDT)

CentralDhaka EasternDhaka

Conclusion  ThewesternDhakawasdevelopedinanunplannedmannerwithshort-termobjec&ves

  Thistypeofdevelopmenthascreatedlong-termirreversiblenega&veimpactonnaturalsystemandsociety.Impactsincludemajorwaterlogging,trafficconges&on,lossofecosystemandwaterbodies

  MajorIndustrializa&onwithintheDhakawatershed;industriesnotcaringforwastewatertreatment;consequenceismajorpollu&onofwaterbodiesandrivers.Impactonpublichealthandecosystemaresignificant

  Majormigra&onfromthecountrysidetoDhakaincreasedthepopula&ondensitytremendouslybutthecityplanningauthorityweremorefocusedondevelopingareasforthetop3-4%ofthehighincomesegmentofthepopula&onignoringlowerincomesegments.

  WeseethesamepagernofdevelopmentintheeasternDhaka;weforeseesimilarfatelikewestDhakaintheeasternpart

  Weseeatleasttenagencieswiththeirownfragmentedplansinves&nginmul&-milliondollarprojectsineasternDhaka.Thereisveryliglecoordina&onorharmoniza&onoftheseplansandprojects.Theseprojectswillonlyserve4-5%ofthehighincomesegmentofthesociety

  Therearegapsinthemandatesandordinancesoftheseagencieswhichdoesnotclearlysayabouttheauthoritywhichwillberesponsibleforoverallcoordina&on.Thereforethereareoverlappingorduplica&ngoftheefforts.

  ToourviewtheCityCorpora&onswhichareheadedbytheMayors-beingpublicrepresenta&vesandaccountabletothepeople-shoulddothecoordina&onandharmoniza&on

  Theroleofthegovernmentshouldbemoreofprovididngthebasicneedslikesafewater,sanita&on,energy,communica&on,disastermanagementmeasures

  Letthepeopleoftheareastogetherwiththemayor’sofficedeterminehowtheywishtoseetheareadevelop

Conclusion