Introduction to Transportation Planning and engineering

The Nepal Road Standard 2070 (NRS 2070, Department of Roads) classifies the public roads of Nepal mainly by function and administrative responsibility into the Strategic Road Network (SRN) and the Local Road Network (LRN).

1. Strategic Road Network (SRN) - under the Department of Roads

• National Highways (H): the main arterial roads, running east-west or north-south, linking the national capital, regional centres, zones/provinces, major economic centres and international border points. Numbered H01, H02, ... (e.g. Mahendra Highway H01). They carry the highest traffic and have the highest design standard.
• Feeder Roads (F): link district headquarters, major production/tourism centres, and important towns to the National Highways. Numbered F001, F002, ...

2. Local Road Network (LRN) - under local governments

• District Roads: Core district roads connect the district headquarters/important centres to the SRN or to other core roads; Other district roads connect smaller centres to the core network.
• Urban Roads: roads inside municipalities (arterial, collector, local streets) under the municipality.
• Village (Rural) Roads: link villages to the district road or to the nearest market; lowest traffic and lowest standard.

Classification table

Other bases of classification

• Design classes / design speed: NRS 2070 sets design standards (design speed, carriageway and shoulder widths, formation width, maximum gradient) according to road class, terrain (plain, rolling, hilly, mountainous) and traffic volume.
• Surface type: paved (bituminous, concrete) and unpaved (gravel, earthen) roads.
• Right of way: NRS 2070 fixes road-width/right-of-way by class (for example, the widest for National Highways).

The figures (widths, speeds) vary with terrain and traffic, so a designer must read the exact table in NRS 2070 for the road class in question.

Road transport is the movement of people and goods on roads using vehicles (buses, trucks, cars, two-wheelers) and non-motorised means.

Advantages of road transport over other modes

1. Door-to-door service: goods and people can be picked up and delivered at the exact origin and destination; rail, air and water need terminals.
2. Flexibility: route, time and speed can be changed any time; no fixed timetable is compulsory.
3. Low initial cost: a road costs much less per km than a railway, airport or ropeway, and can be built in stages (earth, gravel, then paved).
4. Suits short and medium distances: quick and economical for 0-500 km trips.
5. Feeder to other modes: rail stations, airports and river ports are reached by roads.
6. Easy to construct in difficult terrain: gradients up to 12% are acceptable in hills, whereas railway gradients must be below about 2%.
7. Employment and local development: local labour and materials can be used; maintenance by local communities is possible.
8. Small loads allowed: suitable for small quantities of goods and perishable items.

Why road transport is the most relevant mode in Nepal

• Topography: about 83% of the land is hill and mountain. Railways need gentle gradients and large tunnels/bridges, which are very costly; roads can follow the contour with hairpin bends.
• Scattered settlements: population and villages are spread over hills and the Terai, so door-to-door service is needed.
• Low capital: Nepal is a developing country; roads need less investment than rail, air or waterways. Rivers are steep and not navigable.
• Landlocked country: goods from India (Kolkata, Visakhapatnam) and China must pass through border roads.
• Air transport is expensive and cannot reach every place; it is used mainly for remote areas and tourism.
• Social and economic benefits: roads give access to markets, schools and health posts and raise the income of rural people.
• Present practice: more than 90% of passenger and freight movement is by road.

Conclusion: because of difficult terrain, scattered population and limited funds, road transport is the most feasible and practically the only widely available mode in Nepal.

A transportation system is the combination of fixed facilities, vehicles and operating rules that move people and goods from one place to another.

Main components

1. Way (infrastructure/track): the path on which movement takes place - road, rail track, air route, waterway, pipeline.
2. Terminals: points where journeys begin and end or where change of mode takes place - bus park, railway station, airport, port, truck terminal.
3. Vehicles (carriers): the units that carry load - bus, truck, train, aircraft, ship.
4. Motive power (prime mover): the energy source driving the vehicle - petrol/diesel engine, electric motor, jet engine, steam.
5. Operating (control) system: traffic rules, signals, signs, time-tables, licensing, communication and management that keep movement safe and orderly.
6. Users / human element: passengers, drivers, shippers - their needs and behaviour decide the demand.

 Origin --> [Terminal] --> [Way + Vehicle] --> [Terminal] --> Destination
                 ^             ^                    ^
                 |  Motive power + Control system   |

Characteristics of a transport system

• Demand (derived demand: people travel to reach an activity) and supply (capacity of the facility).
• Speed, capacity and safety of the mode.
• Cost: capital, operating and user cost.
• Accessibility and reliability (frequency, punctuality).
• Comfort and convenience; environmental impact (noise, pollution, energy use).
• Flexibility of route and schedule.

A mode of transport is the means or medium by which people and goods are moved. The five main modes are road, rail, water, air and pipeline (with ropeways and cable cars as special cases).

1. Roadways

• Use roads; vehicles run on their own wheels.
• Door-to-door service, flexible, cheap to build; best for short and medium haul.
• Limits: lower capacity, higher accident and pollution rates, high cost for long haul.

2. Railways

• Use steel track; high capacity, low operating cost per tonne-km, suitable for bulk goods and long-distance travel.
• Limits: very high capital cost, fixed route and timetable, needs gentle gradients (about 1 in 100), terminal handling needed.

3. Waterways

• Inland (rivers, canals) and sea/ocean transport.
• Cheapest for bulk cargo and heavy goods; very low energy use.
• Limits: slow, depends on natural water routes and weather, needs ports.

4. Airways

• Fastest mode; useful for long distances, urgent, high-value goods and passengers; reaches remote areas.
• Limits: highest cost per tonne-km, small capacity, depends on weather, large airport cost.

5. Pipelines

• For liquids/gases (oil, gas, water); continuous, safe, low operating cost.
• Limits: only for fluids, fixed route, large initial cost.

6. Ropeways / cable cars

• Used in steep mountain terrain (Kathmandu-Manakamana, Chandragiri); good for hills.

In Nepal, road is dominant, air is important for remote hills, and ropeways serve special cases; rail and inland waterways are still minor.

Urban road patterns are the arrangements of streets and arterials that form the road network of a city. The common patterns are listed below.

1. Rectangular (grid-iron) pattern

  |   |   |   |   |
--+---+---+---+---+--
  |   |   |   |   |
--+---+---+---+---+--
  |   |   |   |   |

• Roads cross at right angles forming rectangular blocks.
• Advantages: simple, easy land subdivision and direction finding, many alternate routes.
• Disadvantages: many 4-way junctions (more conflicts), long travel between diagonal points, monotonous. Example: Chandigarh, Kathmandu New Road area.

2. Radial (star and circular) pattern

      \   |   /
       \  |  /
   ----- (CBD) -----
       /  |  \
      /   |   \

• Roads radiate from the central business district (CBD).
• Advantage: direct access to the centre. Disadvantage: traffic congests at the centre, poor connection between radial arms.

3. Radial-circular (ring-radial) pattern

        ___________
      /   _______   \
     /   /  \ /  \   \
    |   |--- O ---|   |
     \   \__/ \__/   /
      \_____________/

• Radial roads plus one or more concentric ring roads. Ring roads divert through traffic from the centre. Example: Delhi, Kathmandu Ring Road.

4. Radial-web (spider-web) pattern

• Radials linked with circumferential roads of polygon shape; similar to ring-radial but with direct links.

5. Hexagonal pattern

• Roads form hexagons with three-way junctions only; reduces conflict points and gives shorter routes; difficult to lay out.

6. Linear (ribbon) pattern

• City grows along a main road or river (e.g. along a highway); simple but the main road becomes overloaded.

7. Delta (triangular) or irregular pattern

• Mixed pattern developed over time with the terrain (typical in old Nepali towns like Bhaktapur, Patan).

Road (highway) planning is the process of studying present and future travel demand, selecting the roads to be built or improved, fixing their priority and standard, and preparing a programme within the available funds.

Objectives

1. To plan a systematic road network so that all important places are connected economically.
2. To fix priorities - which roads to build first - using a scientific basis such as benefit-cost ratio and traffic volume.
3. To estimate future traffic and provide enough capacity and a suitable design standard.
4. To use available funds and resources in the most economical way.
5. To provide safe, fast, comfortable and economical travel for the road users.
6. To reduce the total transport cost (vehicle operating cost, travel time, accidents).
7. To integrate roads with other modes and with land use and regional development.
8. To keep environmental and social impacts (land acquisition, pollution, resettlement) small.
9. To plan for maintenance and future expansion of the network.

Short note

Road planning is done in stages: (1) road survey (inventory, traffic and economic data), (2) analysis of data to forecast the demand, (3) preparing alternative plans and evaluating them, (4) fixing the priority and a phased programme (e.g. 5-year or 20-year plan), (5) implementation and review. In Nepal the Department of Roads prepares the Strategic Road Network master plans and the Road Sector Development Plans, and the local governments prepare District Transport Master Plans for the local roads.

Transportation moves people, goods and information; it is the backbone of social and economic life of any country.

Economic role

• Trade and market: takes raw materials to industry and products to markets; allows large-scale production and regional specialisation.
• Employment and income: gives jobs in construction, driving, repair and trade; raises rural income.
• Agricultural development: farm produce reaches markets before it spoils, and inputs (fertiliser, seed) reach farmers.
• Industrial development: industries are located where transport is available.
• Tourism: access to Pokhara, Lumbini, Everest region etc. earns foreign currency.
• Land value: land near roads gains value.

Social role

• Access to health, education and services; helps in disaster relief.
• National unity: links distant regions and communities, helps cultural exchange.
• Improves living standard and reduces isolation of remote areas.
• Allows people to move for jobs and settlement.

Political and defence role

• Administration and security forces can reach all areas; roads to the border are strategically important.

In the development of a country

Developed nations have dense transport networks. For Nepal, the east-west Mahendra Highway, north-south corridors (Kodari, Kerung, Kaligandaki) and the strategic roads are the base of national development. But poor transport planning can also give accidents, pollution and congestion, so planning must be balanced.

Public transport is a shared service open to everyone on payment of a fare (buses, trams, trains, micro-buses, metro). Private transport is owned and operated by individuals for their own use (cars, motorcycles, bicycles, own vehicles).

Public transport is more efficient in cities; private transport gives convenience. A good policy balances both and gives priority to public transport.

John Loudon McAdam (1756-1836), a Scottish engineer, is called the pioneer of modern roads because he introduced a scientific and economical way of road construction in the early 19th century.

His main contributions:

• Roads need no heavy foundation; the natural subgrade, kept dry and well drained, carries the load.
• Road made of compacted layers of angular broken stone (about 250 mm total, graded: 50 mm size for base, 25 mm for top), which interlock and bind with their own dust, compacted by traffic.
• A camber (about 1 in 36) and side drains to shed water quickly.
• Showed that the thickness should be decided by the need to protect the subgrade from moisture and not by the weight of stones.

Because of this, roads became cheaper and smoother than the old Telford type. His water-bound macadam is the base of today's bituminous macadam and the road surface used all over the world.

Transportation planning is the systematic process of studying present and future travel demand and deciding the facilities (roads, terminals, services) and policies needed to meet it safely, economically and with minimum harm to the environment.

Steps (briefly)

Setting goals -> data collection (inventory, traffic, socio-economic) -> forecasting demand (trip generation, distribution, mode choice, assignment) -> preparing and evaluating alternatives -> selecting the plan -> implementation and monitoring.

Importance

1. Efficient use of funds: projects are chosen in order of benefit-cost ratio, so scarce money is not wasted.
2. Meets future demand: forecasts growth so that roads do not become congested early.
3. Reduces congestion, accidents and pollution by planning network, public transport and traffic management.
4. Balanced regional development: connects backward areas with markets and services.
5. Integrates land use and transport, so that new development gets access and does not overload old roads.
6. Mode coordination: road, rail, air and public transport work together.
7. Saves time and operating cost for the users and the nation.
8. Gives a framework for private investment and for good policy and legal decisions.
9. Environmental and social protection by studying impacts before the work starts.

Highway engineering deals with the planning, design, construction, operation and maintenance of roads so that people and goods move safely, quickly and economically.

Scope

1. Highway planning: road surveys, traffic studies, demand forecasting, fixing priorities, economic evaluation.
2. Highway alignment and survey: map study, reconnaissance, preliminary and detailed survey.
3. Geometric design: cross-section, horizontal and vertical alignment, sight distance, intersections.
4. Pavement design: subgrade, base, sub-base and surface layers (flexible and rigid).
5. Highway materials: soil, aggregate, bitumen, cement and their tests.
6. Highway drainage: surface, sub-surface drains, culverts and cross-drainage works.
7. Highway construction: earthwork, pavement layers, structures, quality control, equipment.
8. Traffic engineering: studies, regulation, signs, signals, intersection control, road safety, parking.
9. Highway maintenance and management: routine, periodic and emergency maintenance; pavement management.
10. Highway economics and finance: cost-benefit analysis, road user cost, funding and toll.
11. Hill road engineering, landslide control and bio-engineering (important for Nepal).
12. Environmental and social aspects: EIA, land acquisition, resettlement.
13. Highway administration: legislation, road classification, standards (NRS 2070).

Forms of urban road network

1. Grid-iron (rectangular): parallel roads cross at right angles.

  |   |   |   |
--+---+---+---+--
  |   |   |   |
--+---+---+---+--

Simple and flexible, but many conflict points and long diagonal trips.

2. Radial (star): roads spread from the central business district (CBD) like spokes.

     \  |  /
   ---- O ----
     /  |  \

Gives direct access to the centre but causes congestion there.

3. Radial-circular (ring-radial): radials joined by one or more ring roads.

    .-----------.
   /   \  |  /   \
  |  ---- O ----  |
   \   /  |  \   /
    '-----------'

4. Hexagonal: three-way junctions only; fewer conflicts but difficult to set out.

5. Linear (ribbon): development along one main axis (e.g. a highway or river).

6. Irregular/organic: grows with the terrain and history, as in old Kathmandu valley towns.

How a ring road reduces congestion in the city core

A ring road is a circumferential road around the city that connects the radial roads outside the central area.

1. Diverts through traffic: vehicles which only pass the city (trucks, inter-city buses) use the ring instead of entering the core.
2. Links radial roads directly, so traffic going from one suburb to another need not pass through the centre.
3. Reduces vehicles, noise and pollution in the CBD and gives space for pedestrians and public transport.
4. Improves access to the outskirts and helps controlled development of the city fringe.
5. Gives a high-speed alternative route and reduces travel time and accidents.
6. Helps freight movement: heavy vehicles can be restricted in the centre in day time.

Example: the Kathmandu Ring Road (about 27 km) carries traffic around the old city and the core.

The land use-transportation cycle shows that land use and transport affect each other in a repeated loop.

   Land use (houses, shops, offices)
        |                      ^
  creates trips            changes
        v                  accessibility
   Travel demand     <--  and land value
        |                      ^
        v                      |
   Transport facilities (roads, transit) 

Steps of the cycle

1. Land use generates trips: the type, size and location of activities (residential, commercial, industrial) decide the number of trips and their origin and destination.
2. Trips create travel demand on the transport network, leading to traffic and congestion.
3. Transport facilities are built or improved (new roads, public transport) to meet the demand.
4. Accessibility improves along the new facility, so some areas become more attractive.
5. Land use changes: land value rises, new houses, shops and industries are built near the facility, so land use changes.
6. New land use creates new trips, and the cycle starts again.

Example

A new highway is built to a town -> access improves -> land near the highway is developed for shops and housing -> more trips -> more traffic -> the road needs widening.

Importance

Transport and land use planning must be done together; otherwise urban sprawl, congestion and poor access result.

Both are old types of road construction in the early 19th century. Telford (Thomas Telford, 1757-1834) used a heavy stone foundation; Macadam (John McAdam) used compacted broken stones directly on the subgrade.

Sketches

  Telford section                 Macadam section
  ~~ 40mm  wearing coat ~~        ~~ 25 mm stone (top) ~~
  == 100mm broken stone ==        == 50 mm stone ======
  == 100mm broken stone ==        == 50 mm stone ======
  ## hand-set foundation ##       == 50 mm stone ======
  ## stones 170-250 mm  ##        
  ---- subgrade ----              ---- subgrade (kept dry) ----

(Typical thicknesses; Telford total about 400-450 mm; Macadam about 250 mm.)

Comparison

Why Macadam is superior

• Needs much less material and labour, so costs less.
• Quicker to build and easier to repair.
• Its principle (good drainage, camber, compacted angular aggregate) is still the basis of modern roads; Telford's heavy base is unnecessary when the subgrade is dry and well drained.
• It was easily improved to bituminous macadam by adding tar or bitumen.

Historical development of roads in Nepal

• Early period: only foot trails and mule tracks existed for centuries, linking the Kathmandu valley with Tibet and India. Trade routes through Kuti and Kerung were used by merchants and traders.
• Rana period (1846-1951): some roads in the Kathmandu valley; Chandra Shamsher built the Kathmandu-Bhimphedi route with ropeway links, and the first motorable roads were limited to the valley and the Terai near the Indian border (the first vehicles were carried to Kathmandu on shoulders).
• After 1951: planned development started. The first major motorable road, Tribhuvan Rajpath (Kathmandu-Bhimphedi-Hetauda-Birgunj/Raxaul, about 188 km), was built with Indian help (completed 1956). Then the Kathmandu-Kodari Araniko Highway (China, 1967), Prithvi Highway (Kathmandu-Pokhara, 1973), Siddhartha Highway (Pokhara-Sunauli) and the East-West Mahendra Highway (about 1,000 km, built in phases from the 1960s onwards).
• Periodic plans since 1956 gave priority to roads; the Department of Roads (DoR) was formed in 1970s; the Nepal Road Standard (first in 1970s, revised as NRS 2070) guides design.
• Later, rural and district roads grew with district and village development programmes and the Local Road Network.

Present state

• The Strategic Road Network is about 14,000-17,000 km (as per DoR statistics; exact length changes every year) and the total road network, including local roads, is many times larger.
• Many National Highways are only partly black-topped; some feeder roads are gravel or earthen, and some hill roads are not all-weather.
• Problems: landslides and floods, weak maintenance, limited funds, high accident rate, and many roads not built to design standard.

Government plans

• Complete missing links of the Postal highway (Hulaki Rajmarg) and the Mid-hill highway (Pushpalal Lokmarg) and several north-south corridors to the Chinese and Indian borders.
• Kathmandu-Terai (Madhesh) Fast Track expressway and widening of Mahendra Highway.
• Make all district headquarters connected by black-topped roads and reduce travel time between major cities.
• Improve maintenance through the Road Board and sector programmes, with road safety and bio-engineering measures.
• Strengthen local roads through provincial and local governments (details change with national plans, as per the current periodic plan).

Public transport should be given priority over private transport because it serves more people with less cost, space and harm.

1. Road space efficiency: one bus carries 40-60 persons on the road space of 2-3 cars. Roads of limited width, as in our cities, move far more people when buses are favoured.
2. Reduces congestion: fewer vehicles on the road, so time loss and fuel waste fall.
3. Lower cost per passenger: both for the user and the country; the fuel imported per passenger-km is much less.
4. Equity: the poor, students, elderly and women who cannot afford a vehicle get mobility.
5. Less pollution and noise: lower emission per passenger-km; electric buses and trolleys can reduce it more.
6. Fewer accidents per passenger-km.
7. Less parking land: cities need less land for parking and more for people and green space.
8. Saves foreign exchange, as petrol, diesel and private vehicles are imported.
9. Supports compact, efficient land use and economic activity around transit stops.

Hence, planners improve bus service, bus lanes, terminals and fares, and restrict private cars where public transport is available.

Merits of railway over air

1. Lower cost per passenger and per tonne-km, so cheaper for bulk and heavy goods.
2. Large capacity: can carry thousands of passengers or large goods at a time.
3. Less affected by weather (fog, wind), so more reliable.
4. Cheaper terminals: stations are cheaper than airports and nearer to the city.
5. Less fuel use per tonne-km and more environment-friendly if electrified.
6. Safer in terms of casualties per passenger-km, and more space and comfort on long trips.
7. Can serve many intermediate stations along the route.

Demerits of railway compared with air

1. Slower; much more time for long distances.
2. High investment in tracks, bridges and tunnels, especially in rough terrain; fixed route.
3. Cannot reach mountains, islands or places without track; air can reach remote areas directly.
4. Not suitable for urgent and perishable high-value goods.
5. Land acquisition needed for the entire length.
6. Needs gentle gradients, so long detours in hilly country.

For Nepal, air transport is more practical for remote hills while rail is limited to the Terai (proposed Raxaul-Kathmandu and East-West railways).

Advantages of railway over road

1. High capacity and low cost per tonne-km for bulk goods over long distances.
2. Lower energy use and operating cost per tonne-km; electric traction is possible.
3. Safer per passenger-km, with fewer accidents and less pollution.
4. Less congestion; the track is separate from other traffic and has its own right of way.
5. Reliable and punctual, with low effect of weather; good for long-distance passengers.
6. Longer life of the track; low road-wear damage.
7. Comfortable long journeys with space to move, sleep and carry large luggage.

Disadvantages of railway compared with road

1. Very high capital cost for tracks, stations, bridges and tunnels.
2. No door-to-door service; transhipment at the station adds cost and time and gives extra loss/damage.
3. Fixed route and timetable - low flexibility.
4. Unsuitable for short distances and small loads.
5. Needs gentle gradient (about 1 in 100) and large curves; difficult in hills.
6. Long construction time and large land acquisition; needs trained manpower.
7. Maintenance of track and rolling stock is costly.

Because of its flexibility and low initial cost, road is better in the hilly Nepal; rail suits the Terai corridors with heavy freight.

Macadam construction (water-bound macadam, WBM) is a method of building roads from compacted layers of clean, angular broken stone laid directly on a well-drained, cambered subgrade, described by John McAdam about 1820.

Principles

• The road does not need a heavy stone base; the subgrade supports the load if it is kept dry.
• Stones are angular, of uniform size and compact so that they lock together; the fine dust and water bind them.
• The surface is cambered (about 1 in 36) with side drains so water drains away quickly.

Sketch

        crown (camber 1 in 36)
         _______.-------._______
   ~~~~ |  top layer 25 mm stone  | ~~~~
        |  layer 2: 50 mm stone   |
        |  layer 1: 50 mm stone   |
   ======= compacted subgrade ========
   drain                          drain

Total thickness about 250 mm (in layers of 75-100 mm in later practice).

Method

1. Prepare and compact the subgrade to a camber, with drains.
2. Spread the first layer of broken stone (size 50-75 mm), roll it and let traffic or rollers lock the stones.
3. Spread the next layer of smaller stone (25-40 mm) and roll with water; fine screenings fill the voids.
4. Complete the top layer, sprinkle dust or screenings, water and roll again.
5. Later improved with tar or bitumen (bituminous macadam), which is today's base for flexible pavements.

Telford construction was developed by the Scottish engineer Thomas Telford (1757-1834) in the early 1800s. It builds the road on a strong foundation of large stones to carry the load and keep out moisture from the subgrade.

Features

• Foundation layer: large stones (about 170-250 mm), set by hand on edge with the broader face down and narrower end up; gaps are filled with small stones and well rammed.
• Middle layer: about 100 mm of broken stone (about 65 mm size) over the foundation.
• Top layer: about 40 mm of smaller stone (about 25 mm) with binding material.
• The subgrade is nearly flat or slightly cambered; the cross slope is made by the varying thickness of the stones; the crown is about 1 in 45 to 1 in 60, with side drains.
• Total thickness about 400-450 mm.

   ___ 40 mm top layer ___
   === 100 mm broken stone ===
   ##### hand-set stones #####
   ------ flat subgrade ------

Merits and demerits

• Strong, durable and good for weak soil.
• But costly and slow because of skilled hand-setting, so Macadam's cheaper method replaced it.

Long-term transport planning looks ahead 15-25 years and is built on a few basic philosophical elements (principles).

1. Systematic and comprehensive approach: the whole transport system (all modes, users, land use) is studied together and not road by road.
2. Goals and objectives first: the community decides what it wants (mobility, safety, economy, environment) before facilities are chosen.
3. Forecasting: demand is predicted using population, income, land use and vehicle growth.
4. Alternatives and evaluation: several plans are prepared and compared by cost-benefit and other criteria such as social and environmental effects.
5. Continuity (continuing process): planning is regularly updated as conditions change - plan, implement, monitor, review.
6. Co-operation and public participation: government, planners, users and local people take part.
7. Land use-transport integration and intermodal coordination.
8. Sustainability and flexibility: the plan should protect the environment, use resources wisely, and be staged so that it can adjust to future change.
9. Financial feasibility: the plan must be within available funds and be implementable.
10. Equity: benefits for all groups, including the poor and the disabled.