LECTURE 2

Agenda

Road planning and route outline

Transport demand

Definition, mobility and accessibility Road hierarchy and function

HIGHWAY PROJECT APPRAISAL

5 themes: economy safety

environmental impact

accessibility

integration

Economic or investment appraisal provides a framework

for rational decisions on the use of limited resources:

2 broad approaches

Cost benefit (or Social Welfare) analysis

Impact statement approach

HIGHWAY PROJECT APPRAISAL

APPRAISAL SUMMARY TABLE

Scheme Name: Length: Cost:

All-weather route between X and Y AADT: z veh/day

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1.Problem Identification

2. Pre feasibility study(initial identification of solutions)

3.Feasibility study/ Preliminary Engineering design (screening of solutions to preferred option)

4. Final Engineering Design( Specifying the preferred option for bidding)

5. Procurement and negotiation(pre- construction)

6. Implementation/ Construction

7. Operation

8. Monitoring and evaluating

New construction

Upgrading

Rehabilitation

Stage construction

Maintenance

The road sector faces huge challenges including ambitious demands such as better, quicker and cheaper production, construction and maintenance.

Road Project Appraisal/ Assessment- Overseas Road Note 5

It provides a guidance on carrying out feasibility studies for road projects in developing countries.

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The ORN 5 consists of 4 parts

Part 1

Part 2

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Part 3

Part 4

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Appraisal Criteria

Economic Impacts:

Economic analysis of road projects Economic feasibility studies of road projects are used to provide guidance to planners and engineers on transport investment. In addition to helping in taking the decision whether or not to build a road between A and B, they can also address questions such as:

How cost effective is a project? How does one choose between alternative projects?

Which is the best route?

What is the most appropriate design standard?

When should work begin?

Should there be stage construction?

NOT ALL THE CONSEQUENCES OF AN INVESTMENT CAN BE

QUANTIFIED IN ECONOMIC TERMS.

Appraisal Criteria:

Environment:

Noise & vibration noise level Global air quality carbon dioxide Local air quality NOx , CO Water Water quality/ Drainage/ Flood

defense Landscape Geological features

Ecological features Visual impacts Agriculture Heritage Landscape character

Appraisal Criteria:

Accessibility:

Integration

ROAD INVESTMENT MODEL

Calculates the construction cost of a road

Predicts the condition of the road wrt loading & time

Estimates costs of road maintenance and cost of operation of vehicles for each year

Costs discounted back to the base year and summed over the life of the road to obtain the total cost

ROAD INVESTMENT MODEL- uses

ROAD PROJECT

Feasibility stage

Objectives

Background

Institutional & managerial aspects

Traffic

Design

ROAD PROJECT

Define Objectives Determine alternative ways of meeting objectives Preliminary considerations Assessing traffic demand Design and cost different options: Determine benefits for each alternative Economic analysis and comparison of Alternative Cost Benefit analysis Recommendation- Presentation of feasibility Report

ROAD PROJECT

Appraisal Criteria- ORN 5

Main criteria to consider:

Technical

Financial

Economy

Safety

Environment impact

Accessibility

Integration

Sustainability and risks

ROAD PROJECT

ASSESSMENT OF BENEFITS

Vehicle operating cost savings

Time savings

Reduction in road accidents

Economic development benefits

ROAD PROJECT

Feasibility report Summary and conclusions Brief description of project

Objectives Project type Main features Preliminary considerations

Assessment of demand Determining costs Assessment of benefits Economic analysis Financial aspects Other aspects Implementation Plans for monitoring and evaluation

ROAD PROJECT

Transport demand is directly related to land use patterns and to the available transportation systems and facilities.

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Transport

demand

Landuse Transport

facilities

Stages in the development of a road network:

In the light of experience from the developed countries, there would seem to be

three distinct stages in the development of a road network:

1. Initially it is necessary to establish a road network to at least provide a basic means

of communication between centers of population. At this stage little attention is paid

to geometric standards as it is much more important to consider whether a road link

exists at all or, if it does, whether it is passable at all times. 2. The next stage is to build capacity into the road network. Geometric standards

probably have little to contribute to this except in the areas of road width and

gradient. Much more important factors are whether or not a road is paved, or whether

it has sufficient structural strength to carry the traffic wishing to use it.

3. The final stage is to consider operational efficiency of the traffic using the network

and it is at this time that geometric standards become really important.

The designer is faced with the challenge to try and make roads safe no matter which

of these stages of development a road system has reached.

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Traffic engineers/ planners attempt to provide capacity for observed or predicted travel demand by either building new transportation systems or upgrading existing transportation systems.

The improvement of existing transport systems, makes the adjacent and nearby lands more accessible, hence, more accessible.

Building new transportation facilities leads to further increases in landuse development, which in turn results in higher transportation demands.

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Building or upgrading works will either enhance mobility or accessibility or both.

Mobility- Refers to the ability to travel to many destinations.

Accessibility- Refers to the ability to gain entry to a particular site/ area.

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The proximity of a land to a major highway and public transportation facilities is a major factor in determining its value.

A good transportation system must provide for both mobility and accessibility and should be designed to separate both functions to the extent possible to ensure both safety and efficiency.

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Highways systems- mobility is provided by facilities such as freeways, expressways, primary and secondary arterials.

Accessibility is provided by local street networks, which serve only through vehicles (mobility).

Most classes of highway serve both functions to some degree.

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Road hierarchy and function-

ORN 6

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Road hierarchy and function

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Access Roads

Access roads are the lowest level in the network

hierarchy. Vehicular flows will be very light and will be

aggregated in the Collector road network. Geometric

standards may be low and need only be sufficient to provide

appropriate access to the rural agricultural, commercial and

population centres served. Substantial proportions of the total

movements are likely to be by non-motorised traffic.


Collector Roads

Collector roads have the function of linking traffic to

and front rural areas, either direct to adjacent urban centres, or

to the Arterial road network. Traffic flows and trip lengths

will be of an intermediate level and the need for high

geometric standards is therefore less important.


Arterial Roads

Arterial roads are the main routes connecting national

and international centres. Traffic on them is derived from

that generated at the urban centres and from the inter-

urban areas through the Collector and Access road

systems. Trip lengths are likely to be relatively long and

levels of traffic flow and speeds relatively high.

Geometric standards need to be adequate to enable

efficient traffic operation under these conditions, in

which vehicle-to-vehicle interactions may be high.

Documents

LECTURE 2