Policy instruments (3) - Transport Policy and Planning in Great Britain - page 225

on a motorway but does not indicate alternative routes if these would involve using
'local' roads (and hence potentially worsen conditions on them). Similarly the Agency
is investigating ramp metering (i.e. introducing signalised controls at motorway access
points to ensure that its overall volume of traffic is kept within capacity) but this
potentially could create havoc in the management of local networks. A consultation
exercise has been initiated between the Highways Agency and local authorities
in relation to the north-western part of the M25 (where widening to four lanes
commenced in 2008) in an attempt to 'lock in' the benefits of the investment and to
link Agency and local authority control systems 'to produce a better net outcome than
would otherwise be the case' (LTT 448).
14.5 Control of on-street parking
Traditionally highways have served two main functions - to provide for the passage
of traffic and to offer the means of access for servicing adjacent properties. Much
development built before the era of statutory planning control lacks provision within
the curtilage of the site to accommodate the storage of vehicles and for loading and
unloading goods. On-street parking and loading from the kerbside is utilised instead.
Kerbside facilities may also be used for parking by visitors, for picking up and setting
down passengers and for associated waiting. In residential areas with conventional
streets the carriageway typically continues to be used for delivery vehicles and for a
proportion of both residents' and visitors' parking.
In streets with an important traffic function or with frontage uses which generate
significant numbers of access vehicles kerbside parking may be controlled for one or
more of the following main reasons:
• to prevent obstruction (of traffic or access) and to ensure safe operating conditions
• to encourage the use of off-street facilities
• to ration the available on-street space between competing users.
In controlled areas parking is prohibited at and approaching junctions to ensure
adequate sightlines, to maximise throughput at signalised intersections and to protect
turning opportunities for larger vehicles. All stopping is banned in the vicinity of
pedestrian crossings and may be banned at bus stops.
How far remaining kerb-side space is utilised and whether and how it is rationed
will depend on the availability of alternative off-street space (public and private)
within an area and on local authorities' overall parking strategies. Particularly in
commercial centres the total parking provision may deliberately be kept below the
potential demand, particularly for long-stay commuter spaces, as a means of limiting
the volume of traffic with a central destination and thereby aiding congestion or
environmental objectives.
Control of on-street parking is exercised through orders made under the 1984 Road
Traffic Regulation Act and subsequent amendments. Waiting may be prohibited along
defined sections of road for all or part of specified days of the week and any permitted
waiting may be subject to a time limit and/or charge. Additionally restrictions may be
placed on kerbside loading and unloading although normally these are for shorter peak
periods only in order to minimise inconvenience to local businesses. (These periods
may coincide with the operation of a peak-time kerbside bus lane.) The presence of
waiting and loading restrictions is indicated by yellow line markings along the edge