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2.3.3 Advantages and Disadvantages

Whilst PTAL is a simple calculation (easily performed by a spreadsheet) that offers an obvious

indication of the density of public transport provision in an area, it suffers two key problems:

• It does not take into account where services actually go to – for example, a bus that runs every 10

minutes to the bottom of the road is considered better than a bus that runs every twelve minutes

to the city centre.

• The use of arbitrary cut-offs to exclude more distant service access point’s underestimates the

ability to access locations just outside those cut-off distances. For example, a point 960m from

King’s Cross Station (a major public transport station) could have a PTAL of 6, whilst a point 961m

from the same station could have a PTAL of 1 or 2.

Accessibility modelling has been proposed as a solution to these problems. It uses GIS to calculate

door-to-door travel times by public transport to a grid of points around the point of interest, resulting in

a set of isochrones – journey time contours – within which the number of workplaces, households or

residents can be calculated using census data. This method takes into account many more factors

than PTAL, however is much more time-consuming and requires expensive software.

2.3.4 Other Similar Models Applied Internationally

• Land Use and Public Transport Accessibility Index – State of Queensland, Australia19

Queensland Transport has been developing an innovative planning tool that assists planners, policy

makers and development assessors make decisions about future growth and transport.

Called the Land Use and Public Transport Accessibility Index (LUPTAI), the planning tool measures

how easy it is to access health, education, banking, shopping and employment through walking or

public transport, within a specific geographic area.

The concept of 'accessibility' has become increasingly important to transport planning in recent years.

It takes into account people's opportunities to reach commonly used services. Successful

consideration of accessibility, therefore, could result in reduced car use and contribute to a more

sustainable transport system.

The tool uses Geographical Information System (GIS) software to generate a map that gives a visual

representation of the opportunity to reach destinations through public transport, walking or a

combination of both. A five-colour scale shows the level of access for any given area. Data sets about

the locations of services are entered into the system, which produces a map that highlights areas of

None, Poor, Low, Medium or High accessibility.

19

The State of Queensland (Queensland Transport) 2005

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The State of Queensland LUPTAI will assist planners and decision-makers at the state and local level

to:

• determine where to focus urban growth

• maximise land use and transport integration

• assess large scale developments

• assist in writing policy, and

• establish funding priorities.

Users will be able to visualise the impact their projects will have on achieving accessible communities.

LUPTAI is an ideal way to aid decisions about targeting population densities. Contrasting the

traditional method of measuring accessibility by road distance, it is the first of its kind to consider

public transport as a means of access, rather than a facility to be accessed. LUPTAI is being piloted

through a number of applications and is being developed to become "leading edge" new technology.

2.4 Precinct Roads Masterplan

The requirements as set out in the previous paragraphs emphasize the urgent need for the

development of a roads masterplan for the Marlboro GRRL precinct area. A comprehensive roads

master plan for the Marlboro area should be developed within the framework as provided by this

document.

The roads masterplan will be used with the development of a traffic impact assessment as well as with

the development of a travel plan. It must protect the existing and future function of each road and

should span the entire road reserve to include all modes. It should highlight the areas where upgrades

are required and where restrictions should be imposed.

The plan should be developed in the context of existing zoning and land-use as well as future zoning

and land-use. The City’s functional road hierarchy should also serve as primary input although it may

be revised as part of the masterplan development process. The masterplan should furthermore take

cognisance of the park and ride sites, the estimated carrying capacity of all modes (spare capacity),

pedestrian walking contours, access management strategies, planned road upgrades and planned

public transport upgrades.

The Gauteng Policy for Traffic Impact Assessments as discussed in section 0, does allow for a

prospective developer to undertake such a study on behalf of the municipality in its absence. The fees

for this study would be deductible from the developer’s bulk contribution. It is therefore prudent that

the City takes control of this process pro-actively, before development pressures catch up on this

requirement.

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2.5 Bulk contributions20

2.5.1 Purpose and Basic Content

The purpose of the bulk contribution policy is to define responsibilities with regard to the provision of

municipal road infrastructure required by developments in Gauteng Province. The policy will serve as

an interim policy until such time the planned Gauteng Planning and Development Act and Regulations

are promulgated and a final policy adopted.

For the purpose of this UDF, some important elements of the interim policy are:

• Responsibilities are defined with regard to the provision of municipal road infrastructure required

by developments;

• The person or body making an application, is responsible for the provision and installation of

internal roads and to contribute to the cost of external roads (the definitions of which are defined in

the Interim Policy);

• Engineering service contributions must be equitable and fair to both new entrants and existing

residents;

• The full cost of roads required to accommodate developments, must be recovered by means of

engineering service contributions.

• A municipality may allow rebates to applicants as incentives for the promotion of development

objectives;

• The municipality shall, where possible and practical, allow the applicant to make an offer to

provide and install external road infrastructure in lieu of monetary contributions, either partially or

fully;

• Contributions to external roads shall first be used for payment of land provided by the applicant for

external roads and secondly for improving external road infrastructure to the extent deemed

necessary by the municipality to accommodate the development;

• The municipality will establish a road contributions account;

• If a development is located near the boundary of a municipality, the engineering service

contribution will be divided between the adjacent municipalities.

• The contributions to external roads consist of two components, namely a basic external road

contributions and a boundary road component.

• Parameters for the calculation of the calculation of engineering service contributions will be

provided in the Data Manual for Engineering Service Contributions and Traffic Impact

Assessments in Gauteng. The municipality will also annually publish costing rate parameters.

20

Draft Interim Policy for Engineering Service Contributions to Municipal Road Infrastructure in

Gauteng, Gauteng Transport Co-ordination Committee (TCC), May 2007

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2.5.2 Relevance to Transportation UDF

The proposed methodology, as prescribed by the Bulk Contributions Policy document should be

adhered to and adopted by the City as a matter of priority. The policy ties in with the aforementioned

new Policy on the development of Traffic Impact Investigations for Gauteng.

The adoption and application of this methodology should eliminate many ambiguities and uncertainties

that exist with the application and charging of bulk contributions. Where particular leverage exists

within the Bulk Contribution Interim Policy, is in the allowance for rebates by the municipality to

promote development objectives.

The development of traffic assessments and travel plans as discussed in this transportation UDF,

provides the prospective developers in the Marlboro GRRL precinct area with the ability to negotiate

for such rebates, based on the content of this framework document (as provided in sections 0, 0, 0, 0

and Error! Reference source not found.).

Basic external road contributions will be calculated based on vehicle kilometres per hour (capacity

component) as well as vehicle E80 axle-kilometres per day (strength component). Both of these

aspects will be affected directly through the application of the principles as suggested in this

framework document.

Over and above this direct saving, further rebates may be affected by the City in favour of a

demonstrated approach towards measures to reduce vehicle trips, as suggested by the development

of a Travel Plan (section Error! Reference source not found.). This rebate may also be applied to

the boundary road contribution which, in terms of its calculation methodology, will not have a direct

saving component as a result of reduced trips.

Many innovative incentive schemes are used abroad and good examples (best practice) exist of these

methodologies. Many of these initiatives have successfully managed to encourage the private sector

(on a large scale) to partake actively in the management of congestion on public roadways. They

strive towards the creation of public-private partnerships have been sited as one of the key ingredients

required for the sustainability of the transportation system in the City.

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PART 6 – IMPLEMENTATION

The management of nodes and the development that occur within them is vital for a City.

The following are important issues that will need to be managed:

• Monitoring and management of nodes to prevent an oversupply.

• The design approach should focus on integrating various parts of the node in one cohesive whole,

as well as integrating the node within its surrounding environment through adequate pedestrian

linkages.

• Maintain the public environment and infrastructural services up to such a standard that the

maturity of the node could be maintained. Monitoring should consequently take place to identify

and rectify any problems as soon as they occur. Infrastructure and services sufficiently support the

needs of the node and can be upgraded as intensification of the node occurs.

• Manage as a cohesive entity not separate properties.

• Implement a focused programme to upgrade and maintain the public environment at the highest levels.

• Align management interventions with the RUMP process in the regions.

The design codes that will follow are but one management element that should be put into place.

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6.1 Management Guidelines: Transportation

Although good information is available for the Marlboro precinct, development will be guided by

market forces and the exact make-up of the development environment may change from what is

currently foreseen.

The defining elements are therefore provided within a theoretical framework that relates to the class of

road on which it should be implemented. This enables planners and officials to apply the logic and

recommended design code contained in this chapter, beyond the boundaries of this report.

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Class 2 Road

SELECTED ROADWAY ELEMENT DESIGN CODES FOR MARLBORO PRECINCT

CLASS 2 ROAD

Development Cell Circulation

Road Hierarchy

Kerb Radii (Turning Vehicles)

Description: Primary arterial routes providing vehicular mobility with limited off-street access. These roads serve a global / city wide mobility function connecting places of importance throughout the city. These roads are generally forming the ring roads around precincts providing external circulation but do not traverse the precinct itself. Street Classification: Oxford Drive Jan Smuts Drive Bolton Road Characteristics: 1. Speed: 70 – 80 km/h 2. Vehicle volumes: 1750 – 5000 veh/hr 3. Geometry: Dual carriageway (median separated).

Exceptions to the rule exist. 4. Turning Radii: > 10m < 12m 5. Level of Access: LOA 1 – LOA 3 (Limited off-street access) 6. Parking: Off-street (No on-street parking permitted) 7. Surfacing: Road surfacing materials generally should

promote vehicular mobility. Therefore predominantly asphalt is recommended. Alternative surfacing could be considered at intersection with high pedestrian conflicting movements or along public transport routes with dedicated lanes.

Sight Distances

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PEDESTRIAN USERS Conceptualisation of Mid-block Crossings

A: Mid-block Crossing Signal Layout

B: Lighting of Mid-Block Crossings

Mid Block Pedestrian Crossings Signal Layout (Refer to A): Provide signalized mid-block crossings along Class 2 routes with S11 signal heads and pedestrian demand push-buttons. Audible signals to be implemented for sight impaired road users. RTM 4 pedestrian crossing lines to be implemented (minimum width 2.3m / desirable width 5m) Signal heads to be placed 3m from RTM1 stop line. W306 signs to be provided leading up to mid-block crossings. Road Lighting (Refer to B): Street lighting to be provided as per NDoT Pedestrian Guideline Standard (Illustrated adjacent). Kerb Transitions (Refer to C): Kerb ramps must be implemented at all crossing points to accommodate for wheelchair users and sight impaired pedestrians. C: Kerb-Ramp Details

Application Areas: Bus Rapid Transit (BRT) Median station locations High volume pedestrian crossing points that occur mid-block between two land-use attractors (Where intersection spacing is longer than 300m apart.

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PEDESTRIAN USERS (Continued…/) A: Pedestrian Signal Scramble Phase B: Intersection and Signal Layout

Staged Intersection Crossing Dimensions

D: Kerb Transitions

Intersection Crossings: Pedestrian Signal Applications: Three types of pedestrian signal applications are recommended for precinct intersections: Standard Pedestrian Phase Scramble Pedestrian Phase (Refer to A) Early Start Pedestrian Phase Intersection and Signal Layout (Refer to B): Provide signalized pedestrian crossings at all Class 2 route intersections with S11 signal heads and pedestrian demand push-buttons. Audible signals to be implemented for sight impaired road users. RTM 3 pedestrian crossing lines to be implemented (minimum width 1.5m / desirable width 3m) Interlocking pavers or coloured asphalt is recommended at Class 2 junctions serving as gateways to the precinct (indicates higher pedestrian volumes and entrance to the precincts). Staged crossings should be considered. Minimum median width for staged crossings 2m. Road Lighting (Refer to C): Street lighting to be provided as per NDoT Pedestrian Guideline Standard. C: Intersection Lighting

Kerb Transitions (Refer to D): Kerb ramps must be implemented at all crossing points to accommodate for wheelchair users and sight impaired pedestrians.

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PEDESTRIAN USERS (Continued…/)

Application Areas: Road intersection between Class 2 roads and any other road class (Generally Class 3 or 4) NB: Provide pedestrian crossings on left-slip lanes where high vehicle speeds conflict with pedestrian crossings.