Urban Transport

Traffic Study – Traffic Impact

AssessmentRiza Atiq bin O.K. Rahmat

Traffic Impact Assessment (TIA)

All development will generate traffic into current or future transport facilities

All big development will generate internal traffic

TIA will answer the question of:

What will the effect of a development to the surrounding transport facilities

What is the magnitude additional traffic due to the development to the existing traffic

How will the additional traffic effect the current traffic

What is the proposal to alleviate or minimise the impact

TIA activitiesDeveloper

Architect / town planner

Local Authority

Instruction by the local authority to execute TIA

Appointment of a transport engineer

Discussion to determine the scope, study area and study methodology

Collate existing data and information

Traffic Survey

Analyses:•Trip generation•Modal split•Trip distribution•Trip assignment•Analyses of LOS (Level of service)•Problem evaluation•Proposal to alleviate or reduce the identified problems

Review the original lay-out plan and propose any improvement to the client

and land use

Final Report

TIA Content

Existing Situation Analyses Impact to the Road Network Road SafetyInternal Lay-out Parking Space Public Transport Pedestrian, bicycle and disable facilities

TIA Content: 1.Existing Situation

Existing government transport policies for the development area

Structure plan and local plan prepared by the Local Authority

Existing traffic and public transport facilities

TIA Content: 1.Existing Situation (Cont

….)

0

200

400

600

800

1000

1200

6-7 7-8 8-9 9-10 10-11 11-12 12-13 13-14 14-15 15-16 16-17 17-18 18-19 19-20 20-21 21-22

Masa

Tra

ffic

Vo

lum

e (P

CU

/Hr

Menuju P/Bandar

Dari P/Bandar

Existing traffic flows

TIA Content: 1.Existing Situation (Cont..)

….)

345658

5425

621758

451

423598597

287527621

TIA Content: Existing Situation (Cont ….)

Road safety record Pedestrian facilities Identify all planned transport facilities in the

vicinity of the development Identify all other developments in the vicinity

of the development and quantify the combine impact to the external traffic

Identify all existing public transport facilities and the impact of the development to the facilities

Identify potential traffic problem in the development

TIA Content: 2. Analyses

Land use Attraction per 100 sq.m floor area (morning)

Production per 100 sq.m floor area (afternoon)

Office 3.7 person / hr 4.05 person / hr

Hospital 1.52 person / hr 1.32 person / hr

Shopping Centre 0.45 person / hr 0.95 person / hr

Primary school 5.5 person / hr 5.5 person / hr

High School 4.5 person / hr 4.5 person / hr

College / University 2.0 person / hr 1.8 person / hr

Trip Generation

TIA Content: 2. Analyses (Cont ….)

Land use Production per unit (morning)

Attraction per unit (afternoon)

Apartment 2.11 person / hr 1.79 person / hr

Condominium 2.05 person / hr 1.73 person / hr

Flat / low cost house 2.51 person / hr 2.10 person / hr

Single story link house 2.21 person / hr 1.81 person / hr

Double story link house 2.52 person / hr 2.15 person / hr

Semi detached house 2.55 person / hr 2.17 person / hr

Bungalow house 2.65 person / hr 2.25 person / hr

Trip Generation

TIA Content: 2. Analyses (Cont ….)

Morning

Land use Residential unit Production rate

Morning production

Flat 845 2.51 2121

Single story link house 725 2.21 1602

Double story link house 934 2.52 2354

Condominium 837 2.05 1716

Total 7793

Afternoon

Land use Residential unit Production rate

Afternoon Attraction

Flat 845 2.1 1775

Single story link house 725 1.81 1312

Double story link house 934 2.15 2008

Condominium 837 1.73 1448

Total 6543

Example: Trip Generation

TIA Content: 2. Analyses (Cont ….)

Trip Distribution Gravity model

WhereTij = Trip from zone i to

zone jPi = Production of zone

iAj = Attraction of zone jTij = Travel time or travel

cost between zone i and zone j

= Parameter to be calibrated. In Klang Valley, = 2.05 for morning and afternoon peaks.

ij

jijiTAP

KKTij

jijjj

i TAKK /

1

i ijiij TPK

K /

1

TIA Content: 2. Analyses (Cont ….)

Production Constrain Model:

Attraction Constrain Model:

j ijj

ijjiij TA

TAPT

/

/

i iji

ijijij TP

TPAT

/

/

TIA Content: 2. Example

Project Site

TIA Content: 2. Example

Land use QTY Rates Production

Flat 205 2.51515

Link house 431 2.21953

Semi-D 125 2.55319

Bungalow 52 2.65138

Total 1924

Trip Generation

TIA Content: 2. Example (Cont ….)

Destination Travel Time (min)

Estimated attraction

Aj /

Tij2.05

Distribution Trip Distribution

Ipoh 35 92000 62.871 0.271 522

Batu Gajah 30 16500 15.466 0.067 128

Gopeng 10 17200 153.295 0.662 1273

Aj/ Tij2.05 231.632 1.000 1924

Trip Distribution

Distribution = (Aj / Tij2.05 ) / ( Aj / Tij2.05)

TIA Content: 2. Example (Cont ….)

Modal Split (Modal Choice)Influencing factors

Car ownership Household IncomeDistance to the transport facilities Travel TimeTravel CostCar park availability

TIA Content: 2. Example (Cont ….)

Land use Bus % Car / van / jeep %

Motor cycle%

1 Government Office 27.6 57.4 15.0

2 Company Office 48.0 45.6 6.4

3 Bank 49.9 45.0 5.1

4 Hotel 35.9 60.1 4.0

5 Shopping Centre 54.3 40.7 5.0

6 Bungalow house 12.1 84.0 3.9

7 Semi-D house 16.2 79.4 4.4

8 Link House 42.1 48.5 9.4

9 Condominium 13.7 85.1 1.2

10 Apartment 39.9 45.0 15.1

11 Flat 49.5 28.3 21.7

Peak Hour Modal Split in Kuala Lumpur

(Source JKAL, DBKL Annual Report, 1991)

TIA Content: 2. Example (Cont ….)

Land Use Car / Van / Jeep

M / Cycle Bus (big) Bus (Mini)

1 Office 1.55 1.25 75 35

2 Hotel 1.55 1.25 40 25

3 Shopping Centre

2.14 1.30 75 35

4 Houses 2.05 1.38 75 35

Average Passenger (including driver) in Kuala Lumpur

(Source: JKAL, DBKL Annual Report, 1991)

TIA Content: 2. Example (Cont ….)

A local authority has approved a proposed development of a housing estate. It consists of 1250 link houses, 155 semi-D houses, 78 bungalow houses, 390 units condominiums, 820 units apartments and 970 units of flats. Calculate both inbound and outbound traffic flows during morning peak hours.

TIA Content: 2. Example (Cont ….)

Land use Unit Production rate

Producion

Modal Split Person trip Number of Vehicles

Bus car M/C Bus car M/C Bus car M/C

Link house 1250 2.21 2763 42.1%

48.5%

9.4%

1163 1340

260 16 654 188

Semi-D 155 2.55 395 16.2%

79.4%

4.4%

64 314 17 1 153 13

Bungalow 78 2.65 207 12.1%

84.0%

3.9%

25 174 8 1 85 6

Condo 390 2.05 800 13.7%

85.1%

1.2%

110 680 10 1 332 7

Apartment 820 2.11 1730 39.9%

45.0%

15.1%

690 779 261 9 380 189

Flat 970 2.51 2435 49.5%

28.3%

21.7%

1205 689 528 16 336 383

total 44 1939 786

TIA Content: 2. Example (Cont ….)to Ipoh

To PLUS H’way

Proposed Development

to Batu Gajah

to Gopeng

981 pcu/hr

759 pcu/hr

603 pcu/hr

247 pcu/hr

61 pcu/hr

365 pcu/hr

1021 pcu/hr

Assumption: Traffic growth 4.1%Base year: 2010

TIA Content: 2. Example (Cont ….)

To Ipoh

To PLUS H’way

Proposed Development

To Batu Gajah

to Gopeng

790 pcu/hr

1063 pcu/hr

380 pcu/hr

603 pcu/hr

247 pcu/hr

61 pcu/hr

Traffic generated by the development

2014

TIA Content: 3. Impact to the Road Network

Level-Of-Service (LOS) = Flow/Capacity (or V/C)

v/c < 0.9 OK

V/C > 1.0 (LOS = F)

V/C < 0.3 (LOS = A)

TIA Content: 4. Road Safety

Safe to the residences

Safe to the visitors

TIA Content: 5. Internal Lay-out

TIA Content: 6. Parking Space

Malaysia:1 cps / 50sq.m floor

area

or1.25 / residential

unit

TIA Content: 7. Public Transport

TIA Content: 8. Pedestrian, bicycle and disable facilities

TerimakasihThank you