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T.P.D.M. V.2.3
(Al/2001)
3.11 Single Track Access Roads
3.11.1 Introduction
3.11.1.1 In many rural and urban fringe areas there are small isolated developments which will only
generate low vehicular and pedestrian flows and to which it would be both difficult and
expensive to construct normal two lane roads. In such cases a single track access road with
passing bays may be adequate.
3.11.1.2 Many single track access roads have already been constructed, both legally and illegally, and
where properly planned have been found to operate efficiently. The main reasons for a
single track road not working efficiently are:
(i)
(ii)
(iii)
(iv)
(v)
Inadequate provision of passing bays which are not intervisible.
Inadequate provision of parking spaces resulting in passing bays, footpaths, verges or
even the road being used for illegal parking.
Excessive or unsuitable land uses resulting in high traffic flows,
Motorists driving too fast.
Road works or other construction works requiring partial/complete closure of the
road.
3.11.1.3 This section sets out guidelines for the planning and design of single track access roads.
Where a desirable minimum is given, this is normally the absolute minimum for a design
speed of 50km/h, whereas the absolute minimum quoted is that for a design speed of
30km/h.
3.11.1.4 It should be noted that some of these traffic engineering standards are lower than for normal
roads. However, within the constraints imposed when upgrading existing tracks, it is
appreciated that difficulty may still occur in fully achieving the new standard. The designer
should consider together with the Traffic Engineer the relevant implications and agree
whether a lower standard improvement is acceptable.