2nd asian emme/2 users conference hong kong november 2000
TRANSCRIPT
2nd ASIAN EMME/2 2nd ASIAN EMME/2 USERS CONFERENCEUSERS CONFERENCE
HONG KONGHONG KONG
NOVEMBER 2000NOVEMBER 2000
Authors:
Dave McFarlane VKE Engineers
Logan Moodley City of Durban
Using Emme/2 to assess the Using Emme/2 to assess the Impact of and influence the Impact of and influence the
restructuring of the apartheid restructuring of the apartheid citycityCity of DurbanCity of Durban
ContentsContents1.1. IntroductionIntroduction
2.2. BackgroundBackground
3.3. Profile of the CityProfile of the City
4.4. Existing Transport SystemExisting Transport System
5.5. Public Transport RestructuringPublic Transport Restructuring
6.6. Emme/2 Model StructureEmme/2 Model Structure
7.7. ResultsResults
8.8. Using Emme/2 Model in a Predictive ModeUsing Emme/2 Model in a Predictive Mode
9.9. Concluding RemarksConcluding Remarks
In 1994 first democratic government In 1994 first democratic government elected in South Africaelected in South Africa• Dramatic impact on planning Dramatic impact on planning • New legislationNew legislation
Purpose of paperPurpose of paper To describe the methodology employed in the latest To describe the methodology employed in the latest
update of the Emme/2 Modelupdate of the Emme/2 Model• The update and methodology has been influenced by The update and methodology has been influenced by
political changes political changes
To demonstrate how the model will be used in To demonstrate how the model will be used in influencing major decisions regarding restructuring influencing major decisions regarding restructuring and integrating the urban form of the cityand integrating the urban form of the city
1. Introduction1. Introduction
LocalityLocality
LocalityLocality
AfricaAfrica
LocalityLocality
Locality - City of DurbanLocality - City of Durban
Locality - City of DurbanLocality - City of Durban
DURBAN BAYDURBAN BAY
CBDCBD
Prior to 1994Prior to 1994• Six decades of separate development based on Six decades of separate development based on
race apartheidrace apartheid
• Different race groups lived in separately Different race groups lived in separately demarcated areademarcated area
• Distorted spatial structureDistorted spatial structure
• Poorest away from CBDPoorest away from CBD
2. Background2. Background
Prior to 1994Prior to 1994• Duplication of services, public transport, schools, social Duplication of services, public transport, schools, social
facilitiesfacilities
• Emphasis on private transport Emphasis on private transport road building road building
• Poorest furthest away from the CBD .. But totally reliant on Poorest furthest away from the CBD .. But totally reliant on public transport public transport high PT subsidy costshigh PT subsidy costs
2. Background2. Background
I n
d
I
a
n
O
c
e
a
n
INEQUITIESINEQUITIES
Durban CBD
40 min40 min
25 min25 min
10 min10 min
Effects of Effects of Apartheid PlanningApartheid Planning
2. Background2. Background
Post 1994 New Government
New transport legislationNew transport legislation
• regulateregulate• improveimprove• promotepromote
Steps to restructure citiesSteps to restructure cities• densify corridors and nodes - achieve economies of densify corridors and nodes - achieve economies of
scalescale• infrastructure investment to support corridorsinfrastructure investment to support corridors• improve operational performance - tenderingimprove operational performance - tendering
Better integrationBetter integration
Re-calibration of Emme/2 modelRe-calibration of Emme/2 model
Area = 1366 KmArea = 1366 Km22
Population = 2,5 millionPopulation = 2,5 million No. of households= 609 000No. of households= 609 000 60% of employment close to 60% of employment close to
CBD CBD
3. Profile of the City3. Profile of the City
But 30% of employees living But 30% of employees living close to CBD close to CBD long travel long travel distancesdistances
Modal split = 57% by PT - Modal split = 57% by PT - varies from 100% to 0%varies from 100% to 0%
Contributes to 9% of GDPContributes to 9% of GDP Port City - one million containers/annumPort City - one million containers/annum Other activities Other activities • tourism tourism • commercecommerce• subtropical fruitsubtropical fruit• sugar canesugar cane• motor manufacturingmotor manufacturing• agricultureagriculture• constructionconstruction
3. Profile of the City3. Profile of the City
4. Existing Transport System4. Existing Transport System
1 500 buses, 6000 mini-bus taxis, 450 000 cars1 500 buses, 6000 mini-bus taxis, 450 000 cars Over the last twenty years there has been a Over the last twenty years there has been a
significant shift to mini-bus taxissignificant shift to mini-bus taxis
Excellent road system - 3 700 km of freeway, arterial Excellent road system - 3 700 km of freeway, arterial and main routesand main routes
Modes of transportModes of transport
4. Existing Transport System4. Existing Transport System Rail uses old heavy rolling stockRail uses old heavy rolling stock Generally PT system in a poor stateGenerally PT system in a poor state Huge inefficiencies in system mainly due to the Huge inefficiencies in system mainly due to the
distorted spatial structuredistorted spatial structure Currently PT subsidies - US $58 million/annum Currently PT subsidies - US $58 million/annum New legislation has been enacted to restructure New legislation has been enacted to restructure
the PT industrythe PT industry
Modes of TransportModes of Transport
Congestion - Congestion - am peakam peak
Rail InfrastructureRail Infrastructure
Typical BusTypical Bus
Mini-bus TaxiMini-bus Taxi
5. Public Transport 5. Public Transport RestructuringRestructuring The public transport restructuring main thrust is The public transport restructuring main thrust is
to establish a least cost network with optimal to establish a least cost network with optimal
modes on the main corridors modes on the main corridors reduce burden on reduce burden on
subsidysubsidy
Leads to a more efficient and sustainable systemLeads to a more efficient and sustainable system
Supply and demand data surveyed on all public Supply and demand data surveyed on all public
transport modestransport modes
5. Public Transport 5. Public Transport RestructuringRestructuring Basis for PT O-D matrixBasis for PT O-D matrix
High priority public transport network High priority public transport network output output
Rail emphasisRail emphasis
O-D information plus high priority public transport O-D information plus high priority public transport
network network Emme/2 model Emme/2 model
6. Emme/2 Model Structure6. Emme/2 Model Structure NETWORK• 3 712 km of roadway3 712 km of roadway• 406 km of rail406 km of rail• 330 zones (316 internal, 14 external)330 zones (316 internal, 14 external)• Annotation files imported from GIS databaseAnnotation files imported from GIS database
Emme/2 Emme/2 BaseNetworkBaseNetwork
I n
d
I
a
n
O
c
e
a
n
Durban CBD
6. Emme/2 Model Structure6. Emme/2 Model StructureDEMOGRAPHICS 1996 census data1996 census data
• Employment and car ownership - separate Employment and car ownership - separate sourcessources
• Prior to 1996 data collected by race and model Prior to 1996 data collected by race and model structured by race e.g. WHBW, BHBWstructured by race e.g. WHBW, BHBW
• Since 1996 data collected by income group - Since 1996 data collected by income group - high, medium, lowhigh, medium, low
• Income grouping used as a proxy for car Income grouping used as a proxy for car ownership and hence PT usageownership and hence PT usage
• This change necessitated a rethink in the This change necessitated a rethink in the structure of the model structure of the model
6. Emme/2 Model Structure6. Emme/2 Model Structure
• Detail is lostDetail is lost• Required simplification in trip generation and Required simplification in trip generation and
trip distribution models in order to cater for trip distribution models in order to cater for changeschanges
• Typical screenlineTypical screenline
DEMOGRAPHICS
6. Emme/2 Model Structure6. Emme/2 Model Structure
Racial classification Racial classification Income classification Income classification Existing parameters as far as possibleExisting parameters as far as possible Simplify modelSimplify model Census data :Census data :• High income High income R72 000/annum R72 000/annum• Medium Income Medium Income R 30 000 - R72 000/annum R 30 000 - R72 000/annum• Low income Low income R0 - R30 000/annum R0 - R30 000/annum
Why income classification ?Why income classification ?
• Trip generation Trip generation income income• Car usage Car usage income income• Improved distribution of HBW tripsImproved distribution of HBW trips
TRIP GENERATION - OVERALL APPROACH
TRIP GENERATION EQUATIONSHOME BASED WORK (HBW) TRIPS - 2 HOUR AM PEAKHOME BASED WORK (HBW) TRIPS - 2 HOUR AM PEAK
ProductionsProductions = 0.60 * Employed residents= 0.60 * Employed residentsAttractionsAttractions = 0.60 * Employment= 0.60 * Employment
NON-WORK (NW) TRIPS - 2 HOUR AM PEAKNON-WORK (NW) TRIPS - 2 HOUR AM PEAKProductionsProductions = 0.05 * (L.Pop+M.Pop + (1.50*H.Pop))= 0.05 * (L.Pop+M.Pop + (1.50*H.Pop))
+ 0.05*(L.Emp + (2.0*M.Emp) + (4.0*H.Emp))+ 0.05*(L.Emp + (2.0*M.Emp) + (4.0*H.Emp))
Attractions Attractions = (0.008 * L.Pop) + (0.024*M.Pop) + (0.039*H.Pop)= (0.008 * L.Pop) + (0.024*M.Pop) + (0.039*H.Pop)(Activity zones)(Activity zones) +( 0.591*M.Emp) + (1.182*H.Emp) +( 0.591*M.Emp) + (1.182*H.Emp)
AttractionsAttractions = (0.008 * L.Pop) + (0.024*M.Pop) + (0.039*H.Pop)= (0.008 * L.Pop) + (0.024*M.Pop) + (0.039*H.Pop)(Other zones)(Other zones) +( 0.117*M.Emp) + (0.234*H.Emp) +( 0.117*M.Emp) + (0.234*H.Emp)
TRUCK TRIPSTRUCK TRIPSProductionsProductions = (0.04*H.Emp) + (0.1*M.Emp)= (0.04*H.Emp) + (0.1*M.Emp)AttractionsAttractions = (0.05*H.Emp) + (0.07*M.Emp) + (0.007*L. Emp)= (0.05*H.Emp) + (0.07*M.Emp) + (0.007*L. Emp)
6. Emme/2 Model Structure6. Emme/2 Model Structure
High correlation High correlation income and car ownership income and car ownership
Modal split at origins based on graphsModal split at origins based on graphs
MODAL SPLIT
6. Emme/2 Model Structure6. Emme/2 Model Structure
Four modes - auto, rail, bus, mini-bus taxiFour modes - auto, rail, bus, mini-bus taxi Auxillary transit mode - walkAuxillary transit mode - walk
Modal Split Curve (HBW Trips)
Modal Split Curve (NW Trips)
TRIP DISTRIBUTION Develop cost matricesDevelop cost matrices– Car > Travel time matrixCar > Travel time matrix– PT > Cost of travelPT > Cost of travel
Both generated in previous assignmentBoth generated in previous assignment Intra-zonal costs added to each matrixIntra-zonal costs added to each matrix The PT trip cost was refined further :The PT trip cost was refined further :– Determine transposed matrixDetermine transposed matrix– Determine minimum of original and transposed Determine minimum of original and transposed
matricesmatrices– This compensated for off peak direction costsThis compensated for off peak direction costs
6. Emme/2 Model Structure6. Emme/2 Model Structure
TRIP DISTRIBUTION Simple gravity model deterrence function applied Simple gravity model deterrence function applied
to these times/costs : F(c) = exp(-c*to these times/costs : F(c) = exp(-c*)) Separate beta value, impedance matrices used for Separate beta value, impedance matrices used for
PT and carsPT and cars Distribution undertaken for four trip typesDistribution undertaken for four trip types– HBW - low incomeHBW - low income– HBW - medium incomeHBW - medium income– HBW - high incomeHBW - high income– NW trips NW trips
6. Emme/2 Model Structure6. Emme/2 Model Structure
TRIP DISTRIBUTION
Distribution MethodDistribution Method– Two dimensional matrix with two input origin Two dimensional matrix with two input origin
matrices (car and PT) and a single destination matrices (car and PT) and a single destination matrixmatrix
– Model distributes trips based on the deterrence Model distributes trips based on the deterrence matrices and relative attractiveness of car/PT matrices and relative attractiveness of car/PT for each destinationfor each destination
– Use of INRO macro - BALMPROD.MACUse of INRO macro - BALMPROD.MAC– Output eight matrices (4 car, 4 PT), combined Output eight matrices (4 car, 4 PT), combined
into two matrices (car, PT), for assignmentinto two matrices (car, PT), for assignment
6. Emme/2 Model Structure6. Emme/2 Model Structure
CALIBRATION PROCESS Iterative process TG, MS, TD, AssIterative process TG, MS, TD, Ass Emphasis in TD phaseEmphasis in TD phase Three tools used in the calibration process :Three tools used in the calibration process :
1. 1. value is inverse of the average (weighted ) value is inverse of the average (weighted ) cost valuecost value
2. Three dimensional balancing with Emme/22. Three dimensional balancing with Emme/2
origin totalsorigin totalsdestination totalsdestination totalstrips crossing screenlines - 11 in totaltrips crossing screenlines - 11 in total
6. Emme/2 Model Structure6. Emme/2 Model Structure
CALIBRATION PROCESS this whole process was automated for the 11 this whole process was automated for the 11
screenlines for car and PTscreenlines for car and PT
results of the 1st 3-D balance using the first results of the 1st 3-D balance using the first screenline was passed onto the second and screenline was passed onto the second and so forthso forth
origins kept same, destinations modifiedorigins kept same, destinations modified
3. DEMANDJ.MAC - adjustment of demand matrix 3. DEMANDJ.MAC - adjustment of demand matrix based on counts (for comparison/calibration based on counts (for comparison/calibration purposes only)purposes only)
final matrices used in assignment not final matrices used in assignment not adjusted in this wayadjusted in this way
6. Emme/2 Model Structure6. Emme/2 Model Structure
Calibration ProcessCalibration Process
ASSIGNMENT
Car assignment first with PT lines pre-loaded as Car assignment first with PT lines pre-loaded as Pcu valuePcu value
PT assignment run second, speed of road based PT assignment run second, speed of road based PT a function of car assignment speedsPT a function of car assignment speeds
6. Emme/2 Model Structure6. Emme/2 Model Structure
7. Results7. Results Reasonably good resultsReasonably good results
Cars 174 link counts RCars 174 link counts R2 2 = 0.921= 0.921Public Transport 22 screenlines RPublic Transport 22 screenlines R2 2 = 0.984= 0.984Public Transport (buses) 22 screenlinesPublic Transport (buses) 22 screenlines
RR2 2 = 0.890= 0.890Public Transport (mini-bus taxi) 22 screenlines Public Transport (mini-bus taxi) 22 screenlines
RR2 2 = 0.826= 0.826Public Transport (rail) 22 screenlines RPublic Transport (rail) 22 screenlines R2 2 = 0.950= 0.950
Public Transport at ScreenlinesPublic Transport at Screenlines
Link ScattergramLink Scattergram
8. Using Emme/2 in a 8. Using Emme/2 in a Predictive ModePredictive Mode Simulate future scenariosSimulate future scenarios Simple trend projections to various intervention policiesSimple trend projections to various intervention policies Emphasis on public transport enhancementEmphasis on public transport enhancement Main areas of influenceMain areas of influence• influencing abnormal trip length frequency distribution (travel distances)influencing abnormal trip length frequency distribution (travel distances)• by incorporating land use strategiesby incorporating land use strategies• bottleneck eliminationbottleneck elimination
8. Using Emme/2 in a 8. Using Emme/2 in a Predictive ModePredictive Mode
• TDM measuresTDM measures• rationalising PT network - using operating costs rationalising PT network - using operating costs
and fare income as a measure of improvementand fare income as a measure of improvement
Use of PT 57% now Use of PT 57% now 80% target80% target
Refinement andRefinement and
Extension of Extension of PT networkPT network
Future demographicsFuture demographics2.6m - 2.9m2.6m - 2.9m
AIDSAIDS
Existing Trip Length Frequency Existing Trip Length Frequency DistributionDistribution
Preferred Trip Length Frequency Preferred Trip Length Frequency DistributionDistribution
I n
d
I
a
n
O
c
e
a
nDurban
CBD
Proposed Proposed Nodes and Nodes and CorridorsCorridors
City of DurbanCity of Durban
9. Concluding Remarks9. Concluding Remarks Use of Emme/2 has been the backbone in terms of Use of Emme/2 has been the backbone in terms of
determining the HPPTNdetermining the HPPTN Model simplified to replicate current transport Model simplified to replicate current transport
situationsituation In a firm position to test land use strategiesIn a firm position to test land use strategies In a position to influence outcomes In a position to influence outcomes Monitoring of particular parameters within Monitoring of particular parameters within
Emme/2 is now easily achievableEmme/2 is now easily achievable Main tool in developing long range and short term Main tool in developing long range and short term
plans for the Cityplans for the City
City of DurbanCity of Durban