technical note: traffic calming measuresparishes.lincolnshire.gov.uk/files/parish/683/... ·...
TRANSCRIPT
Traffic Calming Measures – November 2015
Thorpe-on-the-Hill Town Council
Ththor/140837 1
1.0 Introduction
1.1 This Technical Note has been prepared by Motion on behalf of Thorpe-on-the-Hill town council to address
concerns relating to the speed of traffic through the village of Thorpe-on-the-Hill. The village is shown in
context with its surrounding highway network on Figure 1.1.
1.2 Thorpe-on-the-Hill is located approximately 12 kilometres south west of Lincoln in between the A46 and the
A57 and is often used by road users as a cut through between the two major roads. The area surrounding
Thorpe-on-the-Hill is generally rural and agricultural in nature.
1.3 The road into Thorpe-on-the-Hill from the south, Fosse Lane, the road that approaches from the south east,
Middle Lane, and the road that approaches from the north, Station Road have a 7.5 tonne weight restriction
in place, meaning that heavy goods vehicles are prohibited from travelling through the village.
Observations of residents suggest that this is a restriction that is not always obeyed.
1.4 The speed limit through the village is set at 30mph, however from the results of speed surveys undertaken
in 2012 it is understood that 85th percentile speeds are as high as 40mph, this is something that is
reinforced by observations of residents. These high speeds are not suited to the residential nature of the
area and have caused safety concerns amongst residents and other road users.
1.5 For a village of this nature, it is important that residents feel safe walking around the local area and
generally, people will only consider walking or cycling on rural or minor roads, if the perception of danger is
reduced. Despite the fact that generally, road traffic casualty rates are falling, they are not falling as
significantly on rural roads. The link between crash severity and speed has been well documented; it is
accepted that the safety risk to road users is directly related to traffic speeds. The way these problems are
tackled can, if done properly, enhance the quality of life for many people.
1.6 This note goes on to consider the technical aspects of reducing speeds through the village.
2.0 Speed of Approach
2.1 To formally assess the speeds of the roads that run into Thorpe-on-the-Hill, Automatic Traffic Counters
(ATCs) were laid on roads approaching the village for a 7-day period. Full outputs of the ATC results are
provided at Appendix A.
Road/Approach Weekday average 85th
Percentile Speed Daily Average Flow
(One Direction)
Middle Lane
Westbound towards Thorpe-on-the-Hill (30mph)
37.6 1268.8
Fosse Lane
Northbound towards Thorpe-on-the-Hill (30mph)
38.2 1120.6
Station Road
Southbound towards Thorpe-on-the-Hill (40mph)
47.8 1761.8
Table 2.1 Summary of ATC Surveys (2012 data)
2.2 Table 2.1 shows that the speeds on approach to Thorpe-on-the-Hill are approximately 10mph in excess of
the speed limit. In order to reduce speeds, a proposed suite of measures are outlined in section 3.
8 Duncannon Street
London
WC2N 4JF
Tel: 020 7031 8141 www.motion-uk.co.uk
Technical Note: Traffic Calming Measures
Project: Thorpe-on-the-Hill
Prepared by: Matthew Stimpson
Approved by: Damian Tungatt
Date: 17/11/2015
Traffic Calming Measures – November 2015
Thorpe-on-the-Hill Town Council
Ththor/140837 2
3.0 Proposed Measures
3.1 Following a review of the local area, the range of traffic calming measures have been reviewed and the
following measures have been proposed for Thorpe-on-the-Hill. Motion drawings 140837-01, 140837-
03,140837-06 show the existing gateway arrangements whilst Motion drawings 140837-02, 140837-04,
140837-05 and 140837-07 show the proposed arrangements.
Gateways
3.2 Progress has been made at developing the Gateways at Thorpe-on-the-Hill by introducing cartwheels with
the name of the village highlighted along with the application of red surface treatment at the points at
which the 30mph speed restriction comes into force on the roads that lead into Thorpe-on-the-Hill.
3.3 Gateways are becoming a feature of traffic calming schemes at the approach to settlements but they may
also be useful in rural areas to highlight to drivers that they are entering an area of changed use or
character, such as an entrance to a length of traffic-calmed road which may involve physical measures such
as carriageway markings and signing and/or a change of speed limit. It is proposed that the progress that
has been made with the Gateways at Thorpe-on-the-Hill is built upon with the intention to increase the
effectiveness of them.
3.4 When designing Gateways, it is important to achieve a good balance between ‘visual impact’ and the local
environment. The existing cartwheels are a very good example of this as gateways can be designed using
local sympathetic materials whilst still conveying the required message to drivers. Speed reductions at
more muted Gateways have been shown to be lower than at sites with bolder designs.
3.5 At the change of speed restriction heading into the village on Fosse Lane and Middle Lane there are already
cartwheels with the village name highlighted, in situ adjacent to the entry lanes. The placement of these is
intended to create more a sense of a gateway to the village and therefore make motorists reduce speed on
the basis that they are entering a residential area. The gateways can be improved by placing planters
either side of the road, in order to increase the presence of the gateway and therefore the effectiveness.
The planters can be placed on the existing verge and will need to be below 0.6 metres in height so as not
to restrict visibility to nearby accesses.
Rumble Strips
3.6 On approach to the gateways on Fosse Lane, Middle Lane and Station Road surface texture can be laid in
strips to give an intermittent rumble effect which can be successful in alerting motorists to a hazard, speed
limit or change in surroundings. This type of rumble strip material should maintain or exceed required
standards of skid resistance.
3.7 At Thorpe-on-the-Hill, it is recommended that the surface is installed across both lanes of the carriageway
so that motorists are not tempted to change lanes to avoid the surface treatment. An innovative use of a
traditional ‘rumble’ device can be the installation of a cattle grid (or imitation version) which will cause the
same effect to a motorist, but with a bypass, plates or bridging sections for cyclists and horse riders.
3.8 All ‘rumble’ devices should be installed well away from residential property or residents should be consulted
prior to their installation. Possible ground borne vibration can occur or noise can result if the route is
regularly used by heavy vehicles.
3.9 Lincolnshire County Council has previously adopted bar markings as a part of their traffic calming package
of measures which forms a type of rumble strip. These are formed by installing transverse bar markings
and reapplying the roadmarking material to create height and produce a ‘rumble strip’. These should not be
placed on bends or steep gradients due to the risk of loss of traction. The skid resistance of the markings
should also be within the specifications set out for the material. The strips must also finish at least 750mm
from the edge of the carriageway so that cyclists can avoid them. Lincolnshire County Council’s
specification for bar markings is provided at Appendix B.
Traffic Calming Measures – November 2015
Thorpe-on-the-Hill Town Council
Ththor/140837 3
3.10 It is recommended that rumble strips are installed on the approach to the gateways to alert the motorist of
the traffic calming measures ahead, so as they can reduce their speed gradually.
Road Narrowing
3.11 The design and application of this type of traffic calming measure has been more scientifically appraised
and the results widely monitored and assessed. The effectiveness is therefore more predictable. In villages
where this type of scheme has been installed, studies have shown that typically both the frequency and
severity of injury accidents can be reduced between 25%- 50% (compared with national trends around
7%). This relates to a general speed reduction of 12mph in some cases with the use of single lane
chicanes.
3.12 Beyond the gateway on Fosse Lane on approach to the village, Fosse Lane continues to be a straight road
in nature and may encourage motorists to increase speed following the gateway. Therefore, it is
recommended that a priority buildout is installed approximately 145 metres north of the gateway. This
restriction gives priority to southbound traffic whilst northbound traffic has to give way. A 1 metre cut
through is provided for cyclists. A diagram showing an indicative priority build out arrangement on Fosse
Lane is shown on Motion drawing number 140837-05, attached.
Street Lighting
3.13 So as to keep motorists alerted of the traffic calming measures whilst it is dark, it is recommended to
provide street lighting at the gateways; this is a measure that contributes to the presence of the gateway
as well as notifying drivers that they are entering a built-up area whilst dark. This measure is been seen
the image below.
Google Image of streetlit gateway in Beaford, Devon.
Traffic Calming Measures – November 2015
Thorpe-on-the-Hill Town Council
Ththor/140837 4
4.0 Costings
4.1 Typical costs associated with the measures outlined in Section 3 are provided in Table 4.1. Please note that
these costs are per feature.
Measure / Costs
Buildout (approx. 8 sq.m)
Precast Concrete Blocks 65mm thick @ £70/m2: £560
HB2 Kerbs @ £40/m: £240
55mm regulating (1.1 tonnes): £240
Preliminaries @ 15%: £155
Contingencies @ 20%: £205
Total: £1,400
Road Markings
Road markings call out charge: £1000
50m Road Markings @2/m: £100
Preliminaries @ 15%: £165
Contingencies @20%: £220
Total: £1485
Bar Markings
High Friction Surfacing @ £130m2: £1950
Preliminaries @ 15%:£300
Contingencies @ 20%: £390
Total: £2640
Lighting Columns
2 x new 5-8m Street Lighting Column @ £2500 each: £5000 (pair)
Preliminaries @ 15%: £750
Contingencies @ 20%: £1000
Total: £6750
Table 4.1: Costings of measures
5.0 Summary and Conclusion
5.1 This note is summarised as follows:
► Vehicle speeds on approach to Thorpe-on-the-Hill are on average 10mph greater than what they should
be. Therefore, it is recommended that the physical traffic calming features of the village are upgraded
to encourage lower speeds;
► It is recommended that the existing gateways are upgraded to include the installation of street lighting
along with some other measures, such as installing planters on one/both sides of the road.
► It is recommended that rumble strips are installed in advance of the gateways to alert motorists to the
change in conditions and promote a gradual reduction in speed; and,
Traffic Calming Measures – November 2015
Thorpe-on-the-Hill Town Council
Ththor/140837 5
► Fosse Lane continues to be straight in nature following the gateway, so to discourage
northbound/incoming motorists to increase speed after passing through the gateway, it is
recommended that a priority buildout is installed, where southbound/ outgoing traffic will have priority.
Figures
n o r t h
L:\Projects\ththor 140837\Figure 1.1.dw
g
Drawing: Revision:
Title:
Project:
232 High Street
Guildford
Surrey
GU1 3JF
T: 01483 531 300
Golden Cross House
8 Duncannon Street
London
WC2N 4JF
T: 020 7031 8141
www.motion-uk.co.uk
Scale: (@ A4)
Thorpe on the Hill
NTS
Figure 1.1-
Village gateway
Village gateway
Village gateway
8
Drain
23.0m
n o r t h
Drawing: Revision:
Title:
Project:
232 High Street
Guildford
Surrey
GU1 3JF
T: 01483 531 300
Golden Cross House
8 Duncannon Street
London
WC2N 4JF
T: 020 7031 8141
www.motion-uk.co.uk
Scale: (@ A4)
L:\Projects\ththor 140837\D
raw
ings\140837-01.dw
g
© Crown Copyright 2012. All rights reserved. Licence number 100043407
Thorpe-on-the-Hill
Middle Lane
Existing Gateway Arrangement
1:500
140837-01-
Location of
Cartwheel
8
Drain
23.0m
n o r t h
Drawing: Revision:
Title:
Project:
232 High Street
Guildford
Surrey
GU1 3JF
T: 01483 531 300
Golden Cross House
8 Duncannon Street
London
WC2N 4JF
T: 020 7031 8141
www.motion-uk.co.uk
Scale: (@ A4)
L:\Projects\ththor 140837\D
raw
ings\140837-02.dw
g
© Crown Copyright 2012. All rights reserved. Licence number 100043407
Thorpe-on-the-Hill
Middle Lane
Proposed Gateway Arrangement
1:500
140837-02-
Location of
Cartwheel
Proposed bar markings as per
Lincolnshire CC typical detail
number TD7/26/23
Lighting Columns
16.2m
n o r t h
L:\Projects\ththor 140837\D
raw
ings\140837-03.dw
g
Drawing: Revision:
Title:
Project:
232 High Street
Guildford
Surrey
GU1 3JF
T: 01483 531 300
Golden Cross House
8 Duncannon Street
London
WC2N 4JF
T: 020 7031 8141
www.motion-uk.co.uk
Scale: (@ A4)
Thorpe-on-the-Hill
Fosse Lane
Existing Gateway Arrangement
1:500
140837-03-
Location of
Cartwheel
1
1
16.2m
n o r t h
L:\Projects\ththor 140837\D
raw
ings\140837-04.dw
g
Drawing: Revision:
Title:
Project:
232 High Street
Guildford
Surrey
GU1 3JF
T: 01483 531 300
Golden Cross House
8 Duncannon Street
London
WC2N 4JF
T: 020 7031 8141
www.motion-uk.co.uk
Scale: (@ A4)
Thorpe-on-the-Hill
Fosse Lane
Proposed Gateway Arrangement
1:500
140837-04-
Location of
Cartwheel
Location of
Planters
Proposed bar markings as per
Lincolnshire CC typical detail
number TD7/26/23
Lighting Columns
1
1
27
FO
SS
E
18.5m
6
LA
NE
FO
SS
E
n o r t h
© Crown Copyright 2012. All rights reserved. Licence number 100043407
L:\Projects\ththor 140837\D
raw
ings\140837-05.dw
g
232 High Street
Guildford
Surrey
GU1 3JF
T: 01483 531 300
Golden Cross House
8 Duncannon Street
London
WC2N 4JF
T: 020 7031 8141
www.motion-uk.co.uk
Scale: (@ A3)
Drawing: Revision:
Title:
Project:
Notes:
Thorpe-on-the-Hill
Fosse Lane
Proposed Priority Buildout
140837-05 -
1:500
See Insert A
Scale 1:250 @ A3
Inset A
Proposed
priority
buildout
Reflective bollards
25.6m
3
3
7
0
Threshing
n o r t h
L:\Projects\ththor 140837\D
raw
ings\140837-06.dw
g
Drawing: Revision:
Title:
Project:
232 High Street
Guildford
Surrey
GU1 3JF
T: 01483 531 300
Golden Cross House
8 Duncannon Street
London
WC2N 4JF
T: 020 7031 8141
www.motion-uk.co.uk
Scale: (@ A4)
Thorpe-on-the-Hill
Station Road
Existing Gateway Arrangement
1:500
140837-06-
25.6m
3
3
7
0
Threshing
n o r t h
L:\Projects\ththor 140837\D
raw
ings\140837-07.dw
g
Drawing: Revision:
Title:
Project:
232 High Street
Guildford
Surrey
GU1 3JF
T: 01483 531 300
Golden Cross House
8 Duncannon Street
London
WC2N 4JF
T: 020 7031 8141
www.motion-uk.co.uk
Scale: (@ A4)
Thorpe-on-the-Hill
Station Road
Proposed Gateway Arrangement
1:500
140837-07-
Proposed bar markings as per
Lincolnshire CC typical detail
number TD7/26/23
Lighting Columns
Appendix A
ATC Results
Appendix B
Lincolnshire CC Bar Markings Specification