Model Presentation to IPWEA 7 November 2014 PNATM Presentation - - PowerPoint PPT Presentation

Palmerston North Area Traffic Model

Presentation to IPWEA

7 November 2014

PNATM – Presentation Overview

• Model Scope and type
• Data collected
• The model
• Forecasting inputs
• Applications

PNCC Aims and Objectives

• Existing model was out of date and used obsolete software
• Greater temporal and spatial resolution required
• Uses the opportunity of the census data collection to fully reflect

the changing demography of the district (incorporating 2012 boundary changes)

• Model to be used for:

─ Forward planning of the road network ─ District plan reviews ─ Specific projects eg Food HQ

• Model software to be flexible and widely used within NZ and
• verseas
• Desire for outputs that could be presented to Councillors etc

PNCC Procurement Process

• Budget of $400k approved by Council
• Independent Traffic Consultant engaged to assist in drafting

the RFP and to assist in evaluating proposals

• Work not subsidised by NZTA, however procurement

process aligned closely with NZTA Procurement Manual

• Procurement method was a Purchaser Nominated Price
• Independent Traffic Consultant retained by Council as Peer

Reviewer throughout duration of contract

Scope – Physical Extent

Scope – Time Periods

• Old model only represented weekday PM Peak
• New model represents the following weekday time periods:

─ AM Peak: 2-hour weekday demand period of 7:30-9:30am with a peak-hour of 8:00-9:00am ─ PM Peak: 2-hour weekday demand period of 4:00-6:00pm with a peak-hour of 4:30-5:30pm ─ Interpeak: 6½ demand period of 9:30am-4:00pm with a peak-hour of 12:00-1:00pm

• Base year = 2013
• Future years = 2021, 2031 and 2041

Scope - Model Type

• Traditional ‘3-Step’ Traffic Model:

─ Trip generation (24-hr) ─ Trip Distribution (24-hr) ─ Trip Assignment (peaks)

• Fully ‘synthetic’
• 16-category Household Structure Model
• 7 trip purposes
• Static ‘macro’ assignment
• Average weekday AM, PM, Interpeak and Daily
• Implemented in CUBE(VOYAGER)

Data Collection

• Census 2013 data

─ Land use data – population, households and employment ─ Census JTW for calibrating trip distribution model

• Demographic information – school/college role
• Count data – calibration/validation

─ PNCC counts ─ MDC/NZ Transport agency counts ─ Bespoke counts at specific locations

• PNCC travel time data – travel time validation
• SCATS Signal time data – network coding
• Horizons bus routes and patronage

Count sites

Bluetooth Data Capture

Bluetooth Data – Facts and Figures

• Data collected in April 2014

─ Five day survey ─ 8 data collection locations ─ 15,000 individual journeys ─ 98 route permutations

• 17% sample size
• Cost effective alternative to ANPR
• First model in NZ to use Bluetooth as a data collection

methodology

• Used for identifying external to external movements, key

journey times and external to internal zone movements

Fleet GPS data capture

• Commercial GPS data used for:

─ HCV matrix and ─ Check of external-external movements ─ Selected travel times for validation

• Uses a range of different sources of commercial vehicle

data, but largely derived from eRUC

• Data sampled over one month (March 2013)
• Sample size = c40% of HCVs, much lower proportion of

LCVs and cars

• First traffic model in NZ to use fleet GPS data

The Model

Output – Traffic Flow

Output – Speed Drop (Link)

Output – Intersection Flow & Delay

Intersection Flow Intersection Delay

Model Calibration and Validation

• Calibration = fit model to data
• Validation = check output against independent data
• Key Calibration/Validation checks

─ Screenline vehicle flow totals (by period and direction) ─ Individual link vehicle flow totals by period and direction ─ HCV flows at key locations. ─ Turning flows at key junctions ─ Travel times on key routes ─ Origin/destination patterns

• Model validates well against industry criteria

Forecasting

• Land use changes

─ Development areas ─ Regional economic growth (population and employment) ─ Changes to educational roles

• Trip making changes

─ Modal shift ─ Changes to trip rates ─ Travel Demand Management

• Network changes

─ New links ─ Intersection modifications

Growth Projections

• Average annual population growth rates for Palmerston

North City (based on residential growth strategy)

─ Low growth = 0.2% per annum to 2031 ─ Medium growth = 0.7% per annum to 2031 ─ High growth = 1.2% per annum to 2031

• Modeling assumes medium growth scenario
• Reductions in population in surrounding rural areas
• 1.1% growth in number of households to 2031

(corresponding drop in average household size)

• Growth is focussed on a couple of key areas (plus a small

amount of infill spread across the city)

Growth Areas

North East Industrial Zone Fielding Longburn City West Whakarongo

Model Applications and Next Steps

• Forecasting (2021, 2031 and 2041)
• Network and land use changes
• Applications

─ Area wide population and employment changes ─ Network changes (for example, second Manawatu river crossing) ─ Policy changes ─ Localised land use changes (new subdivisions, supermarkets etc)

• Lessons learnt regarding use of novel technology to be

shared with the wider industry (NZMUGS)