undp training module subject module volume 1 training manual demand assessment planning n.
Skip this Video
Loading SlideShow in 5 Seconds..
UNDP Training Module Subject Module Volume 1 - Training Manual Demand Assessment Planning PowerPoint Presentation
Download Presentation
UNDP Training Module Subject Module Volume 1 - Training Manual Demand Assessment Planning

Loading in 2 Seconds...

play fullscreen
1 / 99

UNDP Training Module Subject Module Volume 1 - Training Manual Demand Assessment Planning - PowerPoint PPT Presentation

  • Uploaded on

UNDP Training Module Subject Module Volume 1 - Training Manual Demand Assessment Planning. Subject Lecture Material (90 minutes). Objectives of the Module. Educate the participants on T he need for demand assessment to make transportation decisions

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
Download Presentation

PowerPoint Slideshow about 'UNDP Training Module Subject Module Volume 1 - Training Manual Demand Assessment Planning' - galvin

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
undp training module subject module volume 1 training manual demand assessment planning

UNDP Training Module Subject ModuleVolume 1 - Training ManualDemand Assessment Planning

Subject Lecture Material

(90 minutes)

objectives of the module
Objectives of the Module
  • Educate the participants on
    • The need for demand assessment to make transportation decisions
      • Scientific basis for picking and planning projects
    • The time and money and data it takes to develop good forecasts and how to choose tools based on time and money
      • Cannot get the best if time and money are less
    • Assess the reasonableness of model assumptions and forecasts
      • Ensure that the model is fully validated against observed data
      • How to review traffic forecasts and check for reasonableness
who will the users of this module be
Who Will the Users of this Module Be?
  • Policymakers, senior and mid-level staff at the national, state, and city levels, working on transport and related areas such as: land use and development, urban planning and design, environment, road safety, housing, and urban poverty alleviation.
  • NGOs
what is demand assessment planning
What is Demand Assessment Planning?
  • Assessing the demand for a transportation option in a region
    • Develop traffic forecasts for 10-25 year periods
    • Use the forecasts to develop a sustainable transportation system
  • Involves a complicated task of collecting existing transportation data to analyzing demand and forecast future needs
  • Demand Assessment is very common in private companies
    • They will never invest millions without assessing the demand
    • Use demand forecasts to come up with a production/operations plan
why is demand assessment planning important
Why is Demand Assessment Planning Important?
  • Planning helps create a sustainable transportation system that results in increased economic activity
  • Failure to plan results in non-optimal choices that reduce mobility and increase vehicle ownership, leading to severe congestion
  • Essential to design a transportation system, plan operations, and forecast financial viability
  • Demand Assessment identifies corridors with the most potential users.
  • Planning a new system where there is little to no demand is a waste of public money. Planning a system with less capacity will make it crowded and not as attractive.
case studies of inaccurate demand assessment
Case Studies of Inaccurate Demand Assessment
  • Bangkok BTS Skytrain (Cost: 1.5 billion USD; took 5 years to build (1994-1999))
  • A ridership of 6,00,000 riders per day was projected in the first year of operation.
  • Assumptions made were aggressive: such as diversion of 60% of bus riders to rail during peak hours.
  • In the first year of operation, a ridership of only 1,50,000 was recorded.
  • In 2006, after six years of operation, a daily ridership of 3,50,000 has been recorded.
case studies of inaccurate demand assessment1
Case Studies of Inaccurate Demand Assessment
  • Delhi – Gurgaon Expressway (Cost: 10 billion rupees; opened to traffic in January 2008)
  • It carries more than 180,000 PCUs per day, which is much higher than the traffic estimates for the project by 130,000 to 150,000 PCUs per day (the traffic is growing at 9% per year).
  • One of the reason for this under-estimation was that NHAI relied on an outdated traffic study conducted in 1998 at the time of project procurement.
common reasons for bad forecasts
Common reasons for bad forecasts
  • Highly Optimistic Growth Scenarios for future.
    • Growth is never a straight line going up. What goes up comes down.
  • Poor Quality Data
    • The entire basis for forecasts is a statistical model based on data.
    • Garbage in Garbage out.
  • Statistically poor travel models due to bad data, lack of expertise and limited QA/QC.
    • Module has a checklist of items that need to be reviewed to ensure a sound model
current deficiencies and solutions
Current Deficiencies and Solutions
  • No consistent baseline for planning studies
    • Problem: Consultants develop their own population/employment databases and forecasts using vastly different assumptions with no oversight.
    • Impact: Very easy to justify new developments if growth assumptions are high. Conflicting results from different studies using different assumptions. Result in lack of trust of the process.
    • Solution: One region, one approved demographic database.
current deficiencies and solutions1
Current Deficiencies and Solutions
  • Lack of sharing of Data.
    • Problem: Planning agencies do not take possession of their own models and data from consultants.
    • Impact: Every study results in new data collection, new model development and with differences in budget, time and expertise, results are very different. Gross wastage of money and time in redoing what has already been done.
    • Solution: You pay, you own (the model and data) and you share.
current deficiencies and solutions2
Current Deficiencies and Solutions
  • No QA/QC of the modeling process
    • Problem: Most cities do not have the capacity to review technical models
    • Impact: “The mice will play when the cat is away”. The best work is done only when there is a fear that somebody will check it. In the absence of a structured QA/QC process, the quality of work is highly questionable.
    • Solution: Review what you can or hire an independent expert
current deficiencies and solutions3
Current Deficiencies and Solutions
  • No single approved model for all studies
    • Problem: Most cities have several models built for various projects, each at various levels of detail, budget, data collection and expertise.
    • Impact: Impossible to evaluate projects if each of them uses different travel models and datasets.
    • Solution: One Region, One Database, One Model
key steps in demand assessment planning
Key Steps in Demand Assessment Planning
  • Definition of plans (mode, alignment, service etc)
  • Collect Primary and Secondary Data
  • Prepare a Baseline scenario depicting current ground conditions
  • Estimate travel models and validate them
  • Prepare forecasts
  • Evaluate several land use and transportation scenarios to prepare a final shortlist


Data for Demand Assessment

why do we need data
Why Do We Need Data?
  • Understand the socioeconomic and demographic profile of the population
  • Understand the existing transportation infrastructure
  • Understand travel patterns in the city
  • Understand the current situation with respect to traffic congestion, usage of public transport, adequacy of public transport (coverage, crowding, etc.)
what do we do with data
What Do We Do with Data?
  • Create a baseline report to give current status
  • Create market segments
  • Identify the most "transit competitive" corridors
  • Develop Travel Demand Forecasting Models
required land use and employment data
Required Land Use and Employment Data
  • Employment by type (retail, service, etc.) for each traffic analysis zone
  • Land use showing acreage of unused land, parks, agriculture, waste land, etc.
sources of land use and employment data
Sources of Land use and Employment Data
  • City Development Plans
  • Statistical Departments
  • National Information Center – Repository of aggregate data at all levels.
  • Industrial data/ workforce data
  • Data from specific organizations for employment of a particular kind like the Medical Association, Retail association, etc.
vehicle registration data and sources
Vehicle Registration Data and Sources
  • Number of vehicles in the study area by types of vehicles including cycles, motor cycles, auto rickshaws, cars, taxis, medium and heavy duty trucks
  • Information can be obtained from the RTO. Some places such as Karnataka have this information online (Create a table as an example from Bangalore data from the internet)
  • Data for the last 5 years gives a good idea about the rate of growth in vehicle ownership
physical infrastructure
Physical Infrastructure
  • Inventory of all roads, bridges, flyovers, etc. and their capacity in the study area.
  • Inventory of Public transport infrastructure such as bus stops, depots, terminals, etc.
  • Inventory of all pedestrian and bike paths
  • Inventory of utilities, green spaces, etc.
public transport data
Public Transport Data
  • All information on regulated public transport buses and trains in the study area including routes, frequency, fares, rolling stock, ridership, etc.
  • Information on informal public transport such as minibuses, jeepneys, etc.
  • Information on paratransit and demand response transit systems
existing studies
Existing Studies
  • Review existing master plans, comprehensive mobility plans, and comprehensive traffic and transportation study reports
types of surveys
Types of Surveys
  • Household Interview Surveys
  • Origin-Destination Surveys
  • Traffic Volume Count Surveys
  • External Gateway Surveys
  • Commercial Vehicle Surveys
  • Public Transport On-Board Surveys
  • Stated Preference Surveys
good data leads to good forecasts
Good Data Leads to Good Forecasts
  • Data collection should be qualitative and quantitative
    • Sample size based on the size of city and population
    • Data for all modes of travel including walking and biking should be collected
    • Data should be collected for all economic and social classes of population
    • Survey data should be weighted to avoid bias of any kind
household surveys
Household Surveys
  • Household Activity Diaries – To get information on type of household and their travel activities.
  • Sample size should be based on study population.
  • Collect data that includes information from people of all household types, income groups, genders, and age groups
  • A geographically stratified random sampling scheme should be employed to ensure adequate geographic coverage by the overall respondent sample.
methods of sampling data
Methods of Sampling Data
  • Simple Random Sampling:
    • Each unit in the population is assigned an identification number.
    • These numbers are sampled at random to obtain the sample.
    • Each number is chosen entirely by chance and each has the same probability of being chosen.
    • Mostly done in small populations such as a community or a small town.

Interactive: Simple Random Sampling: Pick out random ppl from within the class

methods of sampling data1
Methods of Sampling Data

Why do you think that random selection of people for your sample is so important?

methods of sampling data2
Methods of Sampling Data

In order to make the sample representative of the rest of the community.

methods of sampling data3
Methods of Sampling Data
  • Stratified Sampling:
    • Used to ensure an adequate representation of key subgroups of population/ geographic areas.
    • Stratification may be done by city, planning district, or any other appropriate geographic jurisdiction.
    • The main goal is to divide the study area into relatively homogenous groups.
    • Once the surveying is complete, weights are developed for each group so that the data for all groups may be homogenized.

Interactive: Divide the groups into representatives from government and other organizations respectively. Then conduct random sampling from within these groups.

methods of sampling data4
Methods of Sampling Data
  • Systematic Sampling:
    • This is the process of selecting every ‘I’th unit occurring after a randomly selected unit.
    • An appropriately structured list can result in a systematic sampling procedure which automatically performs stratification as well.
  • Cluster/ Area Sampling:
    • In this method, the total population is first divided into clusters of sampling units, usually on a geographic basis.
    • These clusters are then sampled randomly, and the units within the cluster are either selected in total or else sampled.

Selecting the last participant from every row

methods of sampling data5
Methods of Sampling Data
  • Multi-Stage Sampling:
    • A random sampling technique which is based on the process of selecting a sample in two or more successive stages (may be used when sampling large populations, such as within a large region).
    • Divide the region into districts and sample from total population of these districts.
    • Divide the sampled districts into cities and towns and sample these.
    • This process would go on until sampling has been done at the household level.





sampling error
Sampling Error
  • Error caused by using only a portion of the population rather than the entire population
  • The magnitude of the sampling error can be controlled by the sample size (it decreases as the sample size increases), the sample design, and the method of estimation.
  • Surveys are subject to non-sampling errors.
  • Examples of non-sampling errors are measurement errors and processing errors.
sample size calculation
Sample Size Calculation
  • Factors affecting sample size determination:
    • Response rate
    • Margin of Error
    • Confidence level
    • Response percentage
    • Operational constraints, such as time available to conduct the survey, etc.
weighting and expansion of data
Weighting and Expansion of Data
  • Need for weighting data:
    • In most surveys, it will be the case that some groups are over-represented in the raw data and others under-represented.
    • These misrepresentations are usually dealt with by weighting the data.
    • Weighting involves assigning a survey weight to each case in the data file (value of weight is <1 for over-represented groups and >1 for under-represented groups).
    • It is used to make statistics computed from the data more representative of the population.
expansion of data
Expansion of Data
  • Expansion is the process of assigning weights to different groups of the population
  • Weighting and expansion are often combined into a single factor or weight, which reflects both the relative representativeness of each observation in the sample and the number of similar cases each observation in the sample represents in the population.
  • Separate weights are usually assigned to households, persons, and trips.
  • These weights sum to the number of households, persons, and trips in the population, respectively.

Observed value

Expanded Sample

Expansion Factor

quality of data
Quality of Data
  • Because of time constraints and lack of knowledgeable surveyors, data quality is often very poor.
  • This leads to poor forecasts.
  • As a result, the project is not successful.
  • Agencies should require their consultants to give a report showing all the QA/QC checks that they conducted to ensure quality.



  • This is the process of documenting the current demographic, socio-economic, and transportation situation in the study area.
  • It gives a good idea of the present scenario in the region in terms of identifying demand and supply trends and revealing deficiencies in the system.
  • Developing a baseline report is an absolute necessity in developing short- and long-term transportation plans.
  • This section lists types of data that are necessary to build a good baseline, the sources of said data, and gives examples of maps, tables, and graphs for easy understanding.
data required for baselining
Data Required for Baselining
  • Secondary data:
    • Historic Information
    • Demographic and Land Use Analysis
    • Socio-economic Analysis
    • Transportation Supply
    • Future Planned Improvements
  • Primary data
    • Travel Patterns Analysis
    • State of existing road traffic
    • Public Transport Analysis
baseline historic information
Baseline – Historic Information
  • Historic analysis will also help understand the reasons behind both excellent and inefficient practices. For example:
    • A historic analysis of BEST in Mumbai shows that bus services started in early nineteenth century and how institutional setup led to a high number of employees and low fares
    • BMTC, on the other hand, is a new agency with low employees per bus ratio and has a rule in place to periodically raise fares
demographic analysis
Demographic Analysis
  • Population and employment are the main drivers of trip activity
  • Trips are primarily generated at residences and attracted to jobs
  • The relative location of homes, jobs, and recreational facilities dictates the number and pattern of trips
  • Current population and employment can be mapped to highlight residential and commercial areas
example mumbai metropolitan region
Example: Mumbai Metropolitan Region
  • The graph below shows the population growth rate per census decade for the Mumbai area.
  • The population growth rate peaked first in the core, then in Inner Mumbai, and later Outer Mumbai before falling substantially.

Growth Rate by District (1901-2011) for

Mumbai Larger Metropolitan Region

socio economic analysis
Socio-Economic Analysis
  • It is important to summarize socio-economic data within a given region, as travel behavior of a household depends on factors such as:
    • Number of people in a household: More people results in more trips.
    • Number of workers in a household: More workers means more work trips and fewer recreational trips.
    • Age group of household members: Children and the elderly have different trip patterns. Most trips made by children are to schools by walking, bike, or school bus. Elderly people make very few motorized trips.
    • Income category: Higher income people have a higher number of discretionary trips, such as shopping, social, and recreational trips. Also, these trips tend to be by personal vehicle.
    • Vehicle Ownership: People with personal vehicles make more trips than people who take public transport.
example surat gujarat
Example: Surat, Gujarat

Percentage Distribution of Households by Family Size in Surat

Distribution Members by Age in Surat Average Family Income in Surat

vehicle ownership
Vehicle Ownership
  • Figures below show a steep increase in vehicle ownership and a shift towards more spacious modes of transport – from bicycles to scooters and three-wheelers, and from scooters to cars.

Bangalore Vehicle Ownership Characteristics

Surat Vehicle Ownership Characteristics

transportation supply network
Transportation Supply Network
  • An inventory of the transportation supply network is essential
existing road network
Existing Road Network
  • A baseline report should have an inventory of all existing roads in the region, including bridges, underpasses, flyovers, etc.
  • This will give a good idea of road miles provided.
  • Recent studies have shown that adding more highway miles can increase trips due to latent and induced demand (more people end up travelling because it is convenient), thereby increasing congestion, air pollution, and accidents.
example surat gujarat1
Example: Surat, Gujarat

Extent of the existing road network in Surat , Gujarat and the external gateways

baselining existing public transport network
Baselining: Existing Public Transport Network
  • A baseline should list out all modes of public transport and their characteristics, such as:
    • Routes and areas served
    • Types of buses and fleet size
    • Fares and transfers
    • Average Speeds
    • List of all informal public Transport
pedestrian and non motorized public transport
Pedestrian and Non-Motorized Public Transport
  • Pedestrians and bicyclists make up over 50% of the total modal share in most cities such as Mumbai and Delhi.
  • Walking and weaving through traffic makes non-motorized travellers highly susceptible to accidents.
  • A baseline scenario should list all existing pedestrian and non-motorized facilities.
  • In busy centers of the city, a survey should be conducted to calculate percentage of Non-Motorized Transportation (NMT) users on the roads.

Road Traffic Deaths by Mode of Transport – Percentage of all Fatalities

useful summary tables and figures
Useful Summary Tables and Figures
  • Map of road network highlighting classes of roads
  • Map showing location of external gateways for road, rail, bus
  • Table of total road kilometers by road class, road type, and width
  • Map of public transport routes, color-coded to show various services such as local, express, trunk, feeder, etc.
  • Ridership by route groups, corridors, and operators
  • Types of PT vehicles, their number, fuel type, capacity, and age
  • Fares by class and mode of service
  • List of NMT facilities
  • List of locations with high NMT share
  • List of locations with high accidents relating to NMT
approved future plans
Approved Future Plans
  • Should include all future land use and transportation plans that have been approved or are under construction.
  • All future year analyses should include projects in their baseline and estimate traffic congestion and public transport ridership accordingly.
  • Any new improvements should be complimentary to the approved projects. This list includes:
    • All new bridges, expressways, toll roads, etc.
    • All major public transport lines such as Metrorail, BRT, Monorail.
    • All mega residential and industrial developments.
primary data for baselining
Primary Data for Baselining
  • Primary data is original data that is collected specially for the project at hand.
  • Data is collected as part of field research using surveys, interviews, focus groups, etc.
  • For demand assessment, most of the travel behavior information is collected through primary data surveys such as household surveys, origin-destination surveys, stated preference surveys, etc.
  • Different types of primary data required for baselining are:
    • Travel Pattern Analysis
    • State of Existing Road Traffic
    • Accidents and Safety
    • Air Quality
    • Public Transport Analysis
travel pattern analysis
Travel Pattern Analysis
  • Several surveys, such as household travel surveys, origin-destination surveys, etc. are conducted to capture the behavior of travellers in a region.
  • These surveys are used to summarize data for:
    • Origins and Destinations
    • Number of Trips per person by purpose
    • Modal Split
    • Average Trip Lengths
    • Average Trip Times
    • Average Trip Costs
    • Trips by time of day
example mumbai maharashtra
Example: Mumbai, Maharashtra
  • 2 Crore people in the Mumbai Metropolitan Region make about 2.85 Crore journeys (trips) every day.
  • More than half of these journeys, about 1.5 Crore, are made entirely on foot.

Mode share including walking

Mode share excluding walking

example mumbai maharashtra1
Example: Mumbai, Maharashtra
  • Unaffordable housing has forced residents to move farther away in surrounding municipalities and commute by rail.
  • The average trip length for these commuters is unusually high, at almost 24 km.

Average Trip Length

  • Length of journeys made by all other modes is much lower, ranging from 7 to 12 km, except auto-rickshaws, which are used for even smaller journeys of 1 to 5 km. Walking trips have an average trip length of 1.4km.
state of existing road traffic
State of Existing Road Traffic
  • Congestion is one of the most important measures for evaluating the condition of traffic movement within a region.
  • Traffic volume counts and speed surveys can be conducted to calculate total vehicles by category and speed of vehicles in that category.
  • Mapping this information will immediately identify the congested corridors and help planners develop sustainable transport solutions.
example surat gujarat2
Example: Surat, Gujarat

Congestion in Surat – City Level Network having reached 80% Saturation

Average Daily Traffic in Surat, Gujarat

  • Congestion is one of the most important measures for evaluating the condition of traffic movement within a region.

Speed on Road Network in Surat, Gujarat

accidents and safety
Accidents and Safety
  • A list of accidents and their severity is important in assessing the safety of a region.
  • Analysis of data will also help in identifying modes of transport that cause accidents.
  • Further studies can then be undertaken to research and propose solutions to improve conditions.
example mumbai region maharashtra and surat gujarat
Example: Mumbai Region, Maharashtra and Surat, Gujarat
  • Figures show daily fatalities and accidents in the two case studies

Daily Fatalities in Mumbai Metropolitan Region

Accident Data for Surat, Gujarat

air quality
Air Quality
  • Rapid motorization, dwindling public transport, and declining non-motorized shares in cities have led to increased air pollution.
  • On average, fuel use and CO2 emissions are 3-4 times higher for cars in comparison to two-wheelers.
  • Several cities in India such as Ludhiana, Kanpur, and Jalandhar are rated in the top 50 polluted cities in the world.
  • Several cities are converting their public transport to CNG to reduce CO2 emissions. In 2006, forced by a Supreme Court order, Delhi converted all of its buses to CNG.
public transport analysis
Public Transport Analysis
  • The extent and quality of public transport service should be reviewed in a baseline report. For this purpose, bus occupancy (ridership) and on-board surveys should be conducted to get information on:
    • Number of riders by route and class of service (local, express, AC, etc.)
    • Origins and Destinations of Riders
    • Service Satisfaction
example bangalore karnataka
Example: Bangalore, Karnataka

Bangalore Service and Ridership Details

  • BMTC is one of the few public transport corporations in the world that is profitable.
  • Annual ridership has been increasing every year and has risen from 3.4 million in 2005 to 4.7 million in 2009.

Annual Ridership in Bangalore

useful summary tables and figures1
Useful Summary Tables and Figures
  • Map of road network highlighting classes of roads
  • Map showing location of external gateways for road, rail, bus
  • Table of total road kilometers by road class, road type and width
  • Map of public transport routes, color-coded to show various services such as local, express, trunk, feeder etc.
  • Ridership by route groups, corridors, and operators
  • Types of PT vehicles, their number, fuel type, capacity, and age
  • Fares by class and mode of service
  • List of NMT facilities
  • List of locations with high NMT share
  • List of locations with high accidents relating to NMT
conclusions from baseline analysis
Conclusions from Baseline Analysis
  • Gaps in the Road Network: Identify missing links, incomplete rings, radials, etc.
  • Condition of Road: List of roads in poor condition, encroachments reducing capacity, etc.
  • Adequacy of Public Transport – Identify existing routes with low capacity and potential new routes
  • Safety - List of Intersections with most accidents and modes that cause maximum accidents


Rapid Assessment Techniques

when do we need rapid assessment techniques
When do we Need Rapid Assessment Techniques
  • The agency thinks there is no need for demand assessment: No large transportation investment should be made without demand assessment analysis.
  • There is limited time, budget, and expertise to build a travel model: Curitiba's BRT system was designed without formal traffic modelling. They did, however, use a lot of primary and secondary data to develop demand assessments.
sample studies that can use rapid assessment techniques
Sample Studies that can Use Rapid Assessment Techniques
  • Identifying potential public transport corridors
  • Bus service and route planning
  • Developing rough estimates of revenue on toll roads
  • Calculating approximate demand for a BRT line on a corridor
  • Analyzing the efficacy of existing transportation options


Travel Models and Forecasts

travel demand modeling and forecasting
Travel Demand Modeling and Forecasting
  • A model is a process of using existing land use and transportation data to forecast future traffic and PT ridership.
  • Travel models have been around for more than 40 years.
  • Forecasts are the basis for project approvals in most developed countries.
why do we need models
Why do we Need Models
  • Forecasting Travel Demand is not simple
  • It involves many variables and complex relationships
  • Using rules of thumb and rapid assessment techniques is fine for short-term, medium-budget projects
  • For large-scale investments, it is necessary to develop forecasts that have a proven technical basis.
  • Useful for alternatives analysis
basic concepts in model development
Basic Concepts in Model Development
  • We define a “model” as a set of data and processes that represent a real-world system and describe its behavior under alternative circumstances
  • Models are applied to analysis of future conditions to create forecasts
  • When applying a model, it is always important to use common sense and exercise appropriate judgment in interpreting results
general framework of transport modeling
General Framework of Transport Modeling
  • Theory of supply / demand equilibrium
  • Transportation supply = roads, bridges, trains, buses, airports, boats, planes
  • Transportation demand is derived from demand for activities (goods & services)
  • Transportation costs = expected time, distance, money, etc.
  • Cost / Time increases with demand - congestion
  • Demand decreases with increase in cost/time – diversion

Source: Transport Models: TAG Unit 3.1.2. Department for Transport, June 2005

quiz for participants
Quiz for Participants
  • What information do we use to plan our travel?
the four step modeling process
The Four-Step Modeling Process
  • One (extremely common) method of forecasting travel demand
  • Trip Generation - How many trips are made per household
  • Trip Distribution – Where will the trips go?
  • Mode Choice – Which model will the trips take?
  • Assignment – Which route will the trips take?









travel model inputs
Travel Model Inputs
  • Study Area – Entire Region, City, Single Corridor, Single Intersection
          • Divide the area into Traffic Analysis Zones
  • Transportation Supply - Roadway Network, Public Transport Network, Pedestrian Network
  • Transportation Demand – Households, Jobs
  • Model Parameters – Travel Behavior parameters from surveys
model validation
Model Validation
  • Models are a representation of the current scenario using data and statistical analysis
  • Therefore, all models should be able to match current year numbers. If not, the model is not good
  • Every aspect of a model including input and output data has to be calibrated before using it for forecasts.
  • Clients should ask for a detailed validation report before approving the model
  • Models whose current year numbers do not match should not be approved.




Future Year Forecasts

future year forecasts
Future Year Forecasts
  • Start with a fully validated travel model
  • Update zonal data to future year conditions
  • Update Roadway network and Public Transport networks to include all under-construction and approved projects
  • Run the model to get traffic volumes and PT ridership


future year forecasts important considerations
Future Year Forecasts – Important Considerations
  • All costs such as vehicle operating cost, PT fares, etc. should be based on future year costs (petrol/diesel cost, increase in PT fares, etc.)
  • Prepare a RANGE of forecasts that include low, medium, and high growth scenarios


future year forecasts important considerations1
Future Year Forecasts – Important Considerations
  • DO-NOTHING Alternative
  • Transport Demand Management Options
  • Low investment option
  • High investment option
  • Best option irrespective of cost – Blue




Integration between Land Use and Transportation Planning

need for transport and land use integration
Need for Transport and Land Use Integration
  • Transportation networks and the spatial patterns of land use they serve are assumed to mutually influence each other over time.
  • Changes to transportation networks, such as the construction of a new link or expansion of an existing one, eventually influence the location of investment in land, which in turn influence land prices, etc.


land use impact analysis
Land Use Impact Analysis
  • Improved integration can result in following benefits:
    • It can reduce the need for highway expansion.
    • Quality of communities can be maintained.
    • It can encourage concentration of activities and healthy lifestyle.
    • It can reduce travel delays, vehicle miles travelled, and in turn reduce pollution.

Good land use planning can reduce the need for highway expansion and increase focus on sustainable transport and healthy lifestyle


issues with land use transportation models
Issues with Land-Use Transportation Models
  • Very complicated
  • Data Intensive
  • Take years and lots of expertise to build
  • Even in the US, there are only a handful of models.
  • Wait until these models become more commonplace.
  • Instead, use existing models to test land use scenarios.


integrated land use transportation models
Integrated Land Use Transportation Models
  • Most models of transportation and land use contain a land use component that is integrated with, or at least loosely coupled with, a travel demand model containing a:
    • Network assignment component
    • Congested network travel times
  • These provide a measure of the impact of congestion on regional accessibility and activity location.


analysis of land u se s cenarios in traditional models
Analysis of Land Use Scenarios in Traditional Models
  • Impact of large residential or commercial projects
  • Pros and cons of different locations for large commercial projects
  • Study of the impact of densification of existing city space
  • Impact of urban sprawl and satellite cities