Technical Note: Traffic Calming Measuresparishes.lincolnshire.gov.uk/Files/Parish/683/... ·...

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



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.



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.



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


Contingencies @20%: £220

Total: £1485

Bar Markings

High Friction Surfacing @ £130m2: £1950

Preliminaries @ 15%:£300


Total: £2640

Lighting Columns

2 x new 5-8m Street Lighting Column @ £2500 each: £5000 (pair)



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,



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)


raw

ings\140837-02.dw

g


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


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


1:500

140837-03-

Location of

Cartwheel

1

1

16.2m

n o r t h


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


1:500

140837-04-

Location of

Cartwheel

Location of

Planters



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



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


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


1:500

140837-06-

25.6m

3

3

7

0

Threshing

n o r t h


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


1:500

140837-07-



number TD7/26/23

Lighting Columns

Appendix A

ATC Results

Appendix B

Lincolnshire CC Bar Markings Specification

Technical Note: Traffic Calming Measuresparishes.lincolnshire.gov.uk/Files/Parish/683/... ·...

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