4 Description of Feasibility Study Tasks

Chapter 6 – HCBRT System Design

6.1 NETWORK AND ROADWAY

This section should present the conceptual and feasibility designs and the principal elements for the HCBRT busway and corridor.

6.1.1 Conceptual Design: The conceptual design relates ideas of how the HCBRT system will work, where it will operate/run, who will benefit from the implementation, how it will be operated and what other road works or urban design improvements need to be incorporated in the project.

Based on the basic elements involved, estimates need to be made on how much the infrastructure will cost, how many bus units will be needed and what will be the operating cost. From this data, an estimate can also be made of the level of fares needed to cover operating costs, or the level of subsidy required to provide for the intended demand.

It is also important that the suitability of HCBRT for a particular metropolitan area should be carefully examined with phased introduction of the system proposed if necessary to reflect physical, institutional, and regulatory constraints. Options available for such cases include:

  • Exclusive corridors or corridors with mixed traffic
  • ‘Open’ or ‘closed’ systems
  • Single operator or multiple operators (with or without common ticketing)
  • Bus technology and capacity

It should be noted, however, that technology that works well at low volumes can cause serious problems as passenger flows increase. Some typical examples are the use of too many conventional buses or routes on BRT busways, or the payment of fares – even with smartcards – on the bus units.

6.1.2 Demand Estimation: If O-D data is available, this can be used to aid in demand evaluation, if not, the corridor demand can be obtained directly from traffic counts. The inherent flexibility of bus systems, and the direct link between their demand and costs, permits a wide margin of adjustment.

6.1.3 Network/Corridor Assessment, Selection of Location on the Road Width: Construction costs of the busway can be kept to reasonable levels as articulated buses can handle ramps of up to 10% and turn on a minimum internal radius of 12 metres. (18m articulated units can corner, they have a shorter wheelbase than 12 metre units and their turning radius is actually less.)

  • The road median can be used as part of the station area with a minimum of road works;
  • The use of contra-flow lanes (normally highly dangerous for pedestrians) to access the median is eliminated;
  • One station can serve both busway lanes, hence the overall road width needed for the busway is less;
  • Station infrastructure and maintenance costs are lower, as are staffing and security costs;
  • There is no conflict with parked cars or loading/unloading vehicles;
  • There is no conflict with vehicle access/garage curbs;
  • Potential conflicts at openings of the median can be eliminated by closing these gaps or banning right turns; and
  • Pedestrian and 2-wheeled conflicts can be minimized by using either a high curb on the median or by a fence.

6.1.4 Geometric Design of the Corridor: The information on infrastructure would be collected by homogeneous section, which should be defined at the Conceptual Stage.

  • Length of the road
  • Geometry of the section: number and width of lanes; sidewalks
  • Physical state of the pavements
  • Traffic circulation
  • Location of traffic lights and their phases
  • Inventory of vertical signs
  • Inventory of horizontal signs
  • Bus stops and infrastructure
  • Geometry of intersections

This design should also consider the designs for NMVs and pedestrians, including alternative cross-sections including NMVs tracks, pedestrian facilities, plan/profile for typical sections.

6.1.5 Pavement design: consideration of design period, traffic, sub-grade strength design, drainage arrangement: At junctions and stations the pavement should be reinforced concrete (40cm) in order to support the repeated loads during braking and accelerating. If the busway is a completely new pavement, then a rigid concrete option is recommended; where an existing highway is being adapted, the most cost-effective solution may involve conserving the lower-loaded running sections of the flexible pavement.

6.1.6 Traffic Management: Traffic management measures along the planned BRT corridors should be considered. This covers motorized traffic, 2-wheeled vehicles and pedestrians.

  • Traffic management on roads where the BRT will operate;
  • Traffic management on main roads and/or secondary roads that influence the operation of the new routes;
  • Flows management at conflicting intersections including traffic signals with priority to BRT;
  • Measures for bicycles and signage;
  • Measures for pedestrians and safety;
  • One-way arrangement parallel to the BRT corridor if necessary.).

6.1.7 HCBRT Station Proposed: A sample design for the proposed HCBRT stations should be made, based on local demand and international standards. Station design for pre-paid, at-floor boarding requires that the platforms be set about 96 cm above the pavement level (depending on the units). Low-floor boarding is a possibility, providing that entry is pre-paid. When fares are collected on entry – or even when a smartcard reader is placed on the bus – boarding times are greatly increased and system capacity is lost.

6.1.8 Street Lighting, Furniture and Urban Landscaping: This should present the new urban furniture and the renewal of green/public areas. This aspect of modern bus systems has been included in many successful projects and deserves special attention in this final phase.

6.1.9 Projects for Traffic Diversions: The construction of a surface mass transit system will often require the temporary diversion of traffic, with additional congestion and operating costs. Any major changes in the traffic system should be highlighted at this stage.

6.1.10 Relocation of existing services/utilities: If this is part of the project, these should be shown together with block cost estimates.

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6.2 PUBLIC TRANSPORT CORRIDOR DATA

This section should present the feasibility level public transport data needed for a BRT corridor design.

6.2.1 Initial Data on Supply of Public Transport Services: The data needed to characterize the routes operating in the area of influence of the corridor are:

  • Routes by length, frequency / headway at each critical section of the route and by direction, peak and off-peak;
  • Number of daily trips;
  • Journey times (peak and off-peak) for the whole corridor;
  • Delays, indicating times and causes;
  • Stopping times; and
  • Average passenger waiting times at stops.

6.2.2 Fleet Data: This includes:

  • Number of vehicles in operation on each route, classified by type and nominal capacity;
  • Age of each vehicle; and
  • Seat layouts, doors, circulation, ticket collecting mechanism, handrails, noise levels (internal and external), emissions, etc.

6.2.3 Public Transport Demand: The data presented should cover:

  • Daily demand for each route on the corridor;
  • Daily demand on each section of the corridor;
  • Demand per route in peak and off-peak periods;
  • Average distance and trip time for each user type (by gender if required);
  • Average walking distance for each user type;
  • Turnover indexes;
  • Transfers (if 2 units are needed to make the trip or if a major transfer facility is involved);
  • Areas of trip origins on the corridor; and
  • Areas of trip destinations on the corridor.

The sources for some of this data can be:

  • Visual demand surveys;
  • Boarding/Alighting surveys; and
  • Origin-Destination surveys.

6.2.4 Public Opinion: A public opinion survey of a valid sample of the total passenger demand (work day) on the corridor is needed to identify the basic socio-economic groups and their views. This opinion survey should show how users perceive services in terms of general quality of service, waiting times, physical state of the vehicles and treatment by drivers. The question of cost is usually not included, since the concept of “reasonable, fair or affordable” is difficult to apply to a local monopoly.

6.2.5 Emissions: Information on the release of emissions of global and local pollutants due to the poor quality of the existing transport should be given, which can thus be compared with the new HCBRT system – once in place.

6.2.6 Operational Design of Busway and General Traffic: The operational design of the traffic in the corridor consists in showing how this will be part of the functional design, including signals/phasing, specifications of traffic management measures and materials.

All traffic management measures should be considered to be secondary to the public transport network. In other words, the network and its operational needs are established and the necessary traffic management is then arranged to fit the network. This policy has to be established openly to avoid local political pressures, such as requests to change street direction or keep a conflicting median gap open for a local “authority”. Conflicting left-hand turns should be eliminated where possible;

All intersections with the busway should be controlled by traffic signals, preferably with priority for units using the busway. At sites of high conflict these controls should be enforced by traffic police in order to minimize the risk of units being involved in accidents. This does not imply that traffic police can override the signals. These signals should be programmed for minimum passenger as well as vehicle delay and, if spaced less than 300–400m, should offer synchronization for the trunk routes;

To keep public transport lanes free from private cars and motorcycles, the lanes should be physically segregated /separated, with adequate drainage. Penalties for using this reserved space should be high, as this will minimize encroachment by other users. Good design can reduce it and simplify police enforcement. When using a binary corridor approach (2 one-way streets), with the busway/lane on the left, pedestrian and 2-wheeled access (and hence risk) should be kept to a minimum by using a low fence, preferably with a “green zone” – a strip of grass/bushes.

6.3 Vehicles, Services and Operations

This section should present the choice of bus technology and basic operational system

6.3.1 Bus Type Choice and Detailed Specification: For most HCBRT systems this would be a low-emission (Euro III or similar) 18m articulated bus. Floor height may be Low/Semi-Low/or High. Card readers on units are not advisable for high capacity systems (see Annex 1). HCBRT bus units can have doors on the left or right. For India, where traffic is on the left, the best arrangement for an articulated unit is 4 doors, 110cm wide, and located on the right side of the unit for the system which includes central boarding. The fuel most often used is low-sulphur (metropolitan) diesel – often with bio-fuel additives. This section should include any reasons for choosing the particular unit type and specification – particularly if it differs from international norms.

Normally specifications would include:

  • Chassis type and nominal capacity;
  • Transmission (automatic on trunk routes and all busways);
  • Suspension (air suspension is preferable and obligatory on all busways with at-floor loading in order to maintain the exact height of the unit in relation to the concrete pavement);
  • Specification of environmental contamination with reference to EPA or similar standards;
  • Number of doors and location;
  • Type and dimensions of seats;
  • Corridor circulation;
  • Disposition and height of handrails;
  • Special access mechanisms;
  • Fare collection mechanism (if used); and
  • Useful (working) life of the vehicle.

6.3.2 BRT Services: If a 7 metre busway is used (or a 3.6m median lane), then overtaking in a pedestrian-rich environment will be dangerous. Services will therefore be all-stopping. If overtaking is allowed on specific sections – tightly controlled – then there may be a case for Direct or Express Services. Trunk routes which cross the main central zones – between two or more Integration Terminals – avoid the need for expensive central area terminals and offer greater ‘system coverage’ than radial systems.

6.3.3 Functional Design: The Feasibility Study will produce a Functional Design. This will normally be prepared in AUTOCAD format. If this database is not available, then maps on the same scale, based on aerial or satellite photographs can be used. This design should show how all routes on the corridor will connect to terminals and other mass transport modes and how the traffic network will operate.

Determination of Types of Service and Operating Parameters

The Functional Design should also show:

  • Types of route: trunk, feeder, conventional, complementary, etc.;
  • Types of vehicle for each route;
  • Journey cycle times of the routes;
  • Operating speeds; and
  • Form of payment.

6.3.4 Fleet Requirements: This should include a description of the following items:

  • Relationship between the operational design and the corridor demand
  • Method used to calculate maximum and minimum frequencies, journey cycle times per route, operational speed and nominal capacity of the vehicles
  • Analysis of peak and off-peak periods
  • Level of service offered to users during different periods of the day

The final result should be the total fleet size, per type, as allocated by route during the peak hour, with an estimated daily run-out mileage for each unit type. This can then be used to estimate overall operating cost.

6.3.5 Rationalization of all Bus Flows on the Corridor: There can often be a negative reaction from the public when the HCBRT system is seen to be taking up scarce road space without removing the long bus queues still remaining at the kerbside. The Feasibility Study should indicate what conventional bus flows will still operate on the corridor together with the HCBRT busway.

6.3.6 System of Procurement: This should cover the question of which company or department will be involved in the procurement of units, how the tendering process will be handled, guarantees of transparency and the question of taxes and any import duties.

6.3.7 Detailed Public Presentation: Any mass transit scheme will have a radical impact on the lives of thousands of city inhabitants. The functional design should also include the elements needed for a professional public relation presentation. Geometric designs and maps are often incomprehensible to the general public; architects’ perspective drawings and digital animation can be useful tools.

6.4 Terminals

This section should cover the planning, design, costing and mode of operation of the HCBRT terminals and parking facilities along the corridor.

6.4.1 Locations and Area: These integration terminals should be located at key points on trunk routes, preferably some 7–12km from the central area (or trunk mid point), allowing rationalization of conventional routes into trunk and feeder sections.

Terminal interchange design also has to be of a high standard, with good pedestrian access, using covered platforms of at least 6m width, preferably with the most used routes operating on both sides of the platform to minimize walking distances. When moving from one platform to another, passengers should either use a subway (for large volumes) or a 4m wide pedestrian crossing (normally raised to almost the height of the platform as a traffic calming device).

The system should offer new travel options at interchanges. It has been shown that in all successful HCBRT systems passengers see the interchange as a benefit (greater accessibility) rather than a transfer penalty.

A useful rule-of-thumb based on the dimensions of the interchanges operating in Latin America is to estimate a total interchange area of 360 sq m for each route using 12m units and 500 sq m for routes using 18m articulated units.

The Functional Design of Transfer/ Integration Terminals should be given, showing:

  • Internal circulation of vehicles
  • Passenger circulation
  • Traffic and Pedestrian Flows entering and leaving the station or terminal
  • Points of ticket and unit control
  • Connection points with other modes

The stations and transfer terminals should include facilities for special needs, parking for bicycles and/or private vehicles.

6.4.2 Setting up of Common Utility Offices at Terminals/Major Interchange Points: This has been used successfully in many countries for the payment of bills, taxes, obtaining documents etc.

6.4.3 Platform Dimensioning: The operational aspects of Integration Terminals consist in determining the access and circulation of vehicles and passengers, areas of passenger accumulation, layout of platforms and mechanisms of operational control. Normally platforms are dimensioned, taking into account the intervals and the layover time of each route. Bearing in mind the need for future expansion, reserve platform areas should also be provided.

To obtain the number of platforms, the average arrival interval is considered for all routes. Normally five minutes is sufficient for the off loading and embarking of passengers. To provide a better distribution of routes for available platforms in the terminals in this stage, a minimum of one platform for each feeder route should be adopted, thus allowing a greater level of comfort inside the terminal, facilitating the identification of the routes and allowing for the formation of orderly queues. Feeder route platforms can be 4m, with units stopped on one side.

6.5 Feeder Network and Infrastructure

This section should detail the proposed feeder services.

6.5.1 Feeder Services Planned

In most cases the feeder routes will be strongly related to the parts of the old conventional routes not covered by the trunk route system. Headways should be – at most – 10 minutes; hence, it is common for a unit to be allocated to each feeder route. In some cases a single unit may cover more than one feeder route. If demand is small, then lower cost vans may be operated on the feeders.

6.5.2 Parking for Para-Transit Facilities

At some terminals there may be a need for para-transit feeder services that are not fully integrated. These would use platforms designed as part of the terminal area.

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