The document discusses the key components and process of conducting a Traffic Impact Assessment (TIA) for a development project. A TIA is needed to analyze the traffic effects of a development on surrounding transport facilities. The summary includes: 1) A TIA involves analyzing existing traffic conditions, trip generation from the development, trip distribution patterns, modal split, and impacts on road network capacity, safety, and public transport facilities. 2) The analysis includes traffic surveys, calculating trip generation based on development size and land use, distributing trips based on gravity models, and assigning trips based on modal split ratios. 3) The TIA report outlines impacts and makes proposals to mitigate problems identified, such as exceeding road network capacity

1. Urban Transport
Traffic Study – Traffic Impact
Assessment
Riza Atiq bin O.K. Rahmat

2. Traffic Impact Assessment (TIA)
All development will generate traffic
into current or future transport facilities
All big development will generate
internal traffic

3. 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

4. TIA activities
Developer
Architect / town planner
Local Authority
Traffic Survey
Instruction by the local
authority to execute TIA Analyses:
•Trip generation
•Modal split
Appointment of a •Trip distribution
transport engineer •Trip assignment
•Analyses of LOS (Level of service)
•Problem evaluation
Discussion to determine the scope, •Proposal to alleviate or reduce the identified problems
study area and study methodology
Review the original lay-out plan and
Collate existing data and information
propose any improvement to the client
and land use
Final Report

5. TIA Content
Existing Situation
Analyses
Impact to the Road Network
Road Safety
Internal Lay-out
Parking Space
Public Transport
Pedestrian, bicycle and disable facilities

6. 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

7. TIA Content: 1.Existing Situation (Cont
….)
1200
1000
Traffic Volume (PCU/Hr
800
600
400
200
0
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
Menuju P/Bandar
Dari P/Bandar
Existing traffic flows

8. TIA Content: 1.Existing Situation (Cont..)
….)
658
345 542
5
287
527 423
621 598
597
621 451
758

9. 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

10. TIA Content: 2. Analyses
Trip Generation
Land use Attraction per 100 sq.m Production per 100 sq.m
floor area (morning) 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

11. TIA Content: 2. Analyses (Cont ….)
Trip Generation
Land use Production per unit Attraction per unit
(morning) (afternoon)
Apartment 2.11 person / hr 1.79 person / hr
Condominium 1.73 person / hr

12. TIA Content: 2. Analyses (Cont ….)
Example: Trip Generation
Morning
Land use Residential unit Production Morning
rate 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 Afternoon
rate 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

13. TIA Content: 2. Analyses (Cont ….)
 Trip Distribution
 Gravity model PiAj
Where Tij = KiKj α
Tij = Trip from zone i to Tij
zone j
Pi = Production of zone
i 1
Ki =
Aj = Attraction of zone j
Tij = Travel time or travel
∑j
K j A j / Tijα
cost between zone i and
zone j
α = Parameter to be 1
Kj =
calibrated. In Klang
Valley, α = 2.05 for ∑i K i Pi / Tijα
morning and afternoon
peaks.

14. TIA Content: 2. Analyses (Cont ….)
α
Production Constrain Aj / T ij
Tij = Pi
Model:
∑ j
Aj / T α
ij
Attraction Constrain α
Pi / T ij
Model: Tij = A j
∑ P /T i i
α
ij

15. TIA Content: 2. Example
Project
Site

16. TIA Content: 2. Example
Trip Generation
Land use QTY Rates Production
Flat 205 2.51
515
Link house 431 2.21
953
Semi-D 125 2.55
319
Bungalow 52 2.65
138
Total
1924

17. TIA Content: 2. Example (Cont ….)
Trip Distribution
Destination Travel Time Estimated Aj / Distribution Trip
(min) attraction Tij2.05 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
ΣAj/ Tij2.05 231.632 1.000 1924
Distribution = (Aj / Tij2.05 ) / (Σ Aj / Tij2.05)

18. TIA Content: 2. Example (Cont ….)
Modal Split (Modal Choice)
Influencing factors
Car ownership
Household Income
Distance to the transport facilities
Travel Time
Travel Cost
Car park availability

19. TIA Content: 2. Example (Cont ….)
Peak Hour Modal Split in Kuala Lumpur
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
(Source JKAL, DBKL Annual Report, 1991)

20. TIA Content: 2. Example (Cont ….)
Average Passenger (including driver) in Kuala Lumpur
Land Use Car / Van / M / Cycle Bus (big) Bus (Mini)
Jeep
1 Office 1.55 1.25 75 35
2 Hotel 1.55 1.25 40 25
3 Shopping 2.14 1.30 75 35
Centre
4 Houses 2.05 1.38 75 35
(Source: JKAL, DBKL Annual Report, 1991)

21. 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.

22. TIA Content: 2. Example (Cont ….)
Land use Unit Product Prod Modal Split Person trip Number of Vehicles
ion rate ucio
Bus car M/C Bus car M/C Bus car M/C
n
Link house 1250 2.21 2763 42.1 48.5 9.4 1163 134 260 16 654 188
% % % 0
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
% % %
total 44 1939 786

23. TIA Content: 2. Example (Cont ….)
to Ipoh
To PLUS H’way
981
pcu/hr
247
pcu/hr 759 pcu/hr
Proposed
Development
Assumption: Traffic growth 4.1%
365 Base year: 2010
pcu/hr
to Batu 603 pcu/hr
Gajah 61 pcu/hr
1021
pcu/hr
to Gopeng

24. TIA Content: 2. Example (Cont ….)
To Ipoh
2014
Traffic generated by
the development
To PLUS H’way
247 pcu/hr
Proposed
Development
790 pcu/hr
380 pcu/hr
To Batu 603 pcu/hr
Gajah 61 pcu/hr
1063
pcu/hr
to Gopeng

25. 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)

26. TIA Content: 4. Road Safety
Safe to the
residences
Safe to the visitors

27. TIA Content: 5. Internal Lay-out

28. TIA Content: 6. Parking Space
Malaysia:
1 cps / 50sq.m floor
area
or
1.25 / residential
unit

29. TIA Content: 7. Public Transport

30. TIA Content: 8. Pedestrian, bicycle and
disable facilities

31. Terimakasih
Thank you