development road specification and construction amended february 2009

8/2/2019 Development Road Specification and Construction Amended February 2009

1/162

Version 2.0 28 May 2009

Lincolnshire County Council

DEVELOPMENT ROADSPECIFICATION AND

CONSTRUCTION2008

To be used in theConstruction of Development Roads

which are to becomeHighways Maintainable at the Public Expense

Lincolnshire County CouncilCity HallBeaumont FeeLINCOLN LN1 1DN

www.lincolnshire.gov.ukL.C.C.


2/162


INTRODUCTORY STATEMENT

This document supersedes Development Road Specification and

Construction and Design Standards for Industrial Estate Roads 1999 andversions 1.0 and 1.1 of this edition

It should be read and used in conjunction with the Lincolnshire Design Guidefor Residential Areas.

Electronic copies of this Specification can be found on the County Councilwebsite, LCC Connects:-

www.lincolnshire.gov.uk on which type Development Road Specificationin thesite searchwhich links to Highways Developmentwhich in turn enables this

specification to be downloaded.

This Specification will be subject to review and amendment. The version ofthe Specification, including the Key Construction and Inspection StageCertificates (Appendix 1) current at the time of signing the Section 38agreement, will apply to works covered by that agreement.

Version 2.1 of this document is the third revision and is dated 28 May 2009.The changes introduced by this version are indicated by a vertical line in theright hand margin.


3/162


CONTENTS

Clause Page NoGENERAL GUIDANCE NOTES

IntroductionPlanning PermissionRoad LayoutVertical AlignmentDisposal of Road Surface WaterDrawingsInspection, Testing and ReportingPermanent Traffic Signs and Road MarkingsWorks Within the Public HighwayCDM RequirementsSpecifications, Codes of Practices EtcCommuted Maintenance Payments

111112234555

1. CONSTRUCTION STANDARDS1.1 General Principles 61.1.1 Conformity of Standards 61.1.2 Variation of Approved Details 61.1.3 Construction Charts 61.1.4 Roads Carrying Over 2.0 m.s.a. 61.1.5 Concrete Roads 61.1.6 Site Investigation 61.1.7 Sub-grade 81.1.8 California Bearing Ratio Test (C.B.R.) 81.1.9 Carriageway Construction Thickness (Frost Susceptibility) 81.1.10 Laboratory Results and Test Reports 91.1.11 Contaminated Land 9

1.1.12 Plate Bearing Tests 91.1.13 Approved Suppliers, Test Methods and Working Standards 91.1.14 Trafficking of Binder Course 101.1.15 Trafficking of Roads, Contamination and Storage of Materials 101.1.16 Kerbing 101.1.17 Minimum Depth Flexible Construction 111.1.18 Commuted Maintenance Payments 12

General Sectional Detail (Figure 1/1) 141.2 Sub-base 151.3 Binder Course 151.4 Surface Course 151.5 Footway Construction 15

Junction Detail with existing Carriageway (Figure 1/2) 16

Domestic Vehicle Crossings (Figure 1/3) 17Heavy Duty Access Crossing (Figure 1/4) 18

1.6 Vehicle Access Crossings 191.7 Waiting Bay or Layby Construction 191.8 Tactile paving at crossings for pedestrians 19

Dropped Kerb Detail (Figure 1/5) 20Use of Tactile Paving (Figure 1/6) 21

1.9 Small Block Pavers 22Construction Chart 1 (Up to 0.25 m.s.a.) Normal Flexible Construction 23Construction Chart 2 (Up to 0.25 m.s.a.) Min. Depth Flexible Construction 24Construction Chart 3 (Up to 0.25 m.s.a.) Small Block Paver Construction 25Construction Chart 4 (Up to 2.0 m.s.a.) Normal Flexible Construction 26Construction Chart 5 (Up to 2.0 m.s.a.) Min. Depth Flexible Construction 27

Construction Chart 6 (Up to 2.0 m.s.a.) Small Block Paver Construction 28


4/162


Clause Page No

2. TYPICAL SECTIONS THROUGH CARRIAGEWAY EDGEAND FOOTWAY EDGE

2.1 Carriageway, Kerb and Footway Detail Charts 1, 2, 4, and 5 (Figure 2/1) 292.2 Carriageway, Kerb and Footway Detail Chart 3 and 6 (Figure 2/2) 29

2.3 Carriageway, Kerb and Footway Detail Shared Surface Road Plan(Figure 2/3)

30

2.4 Carriageway, Kerb and Footway Detail Shared Surface Road Section(Figure 2/4)

31

2.5 Channel Block and Kerb Detail (Figure 2/5) 322.6 Service Margin Detail Shared Surface (Figure 2/6) 322.7 Chart 1 Type Road Utilising Alternative Method of Kerb Installation

(Figure 2/7)33

(Two Stage Construction; Kerbing to be added at a later stage)

3. TRAFFIC AND SAFETY MEASURES DURING CONSTRUCTION3.1 Temporary Traffic Signs 343.2 Control of Traffic 34

3.3 Temporary Diversion of Traffic 343.4 Safety Codes 343.5 Excavations 343.6 Materials on the Highway 343.7 Mud, etc. On the Highway 34

4. SITE CLEARANCE4.1 Clearing site 35

5. DRAINAGE5.1 General principles 36-375.2 Design-Layout 37-385.3 Connections to existing drains or public sewers 395.4 Hydraulic Design 39-405.5 Pipes, Couplings, Fittings and Ancillary Products 41-425.6 Manholes 42-435.6.12 Step Rungs 435.6.13 Ladders 445.6.15 Safety Chains 445.6.20 High Strength Concrete Topping to Inverts and Benchings 445.6.23 Access to inverts greater than 600mm diameter 445.6.24 Rocker Pipes 44-455.6.26 Warning Signs 45

Figure 5/1 Typical manhole detail Type A 46Figure 5/2 Typical manhole detail Type B 47

Figure 5/3 Typical manhole detail Type C 48Figure 5/4 Typical manhole detail Type D 49Figure 5/5 Access to Invert for Pipe Diameter Exceeding 600mm 50Figure 5/6 Typical Outfall Safety Grille 51

5.7 Gullies and Connections 52Figure 5/7 Typical gulley details 53

5.8 Brickwork and Blockwork 545.9 Covers and Frames 54-565.10 Excavation for drainage works 565.11 Backfilling of trenches and filter drains 56-575.12 Pipelaying 585.13 Bedding, laying and surrounding of pipes 58-605.14 Inspection testing and cleansing 60-62


5/162


Clause Page No6. EARTHWORKS6.1 Formation Level 636.2 Topsoil 636.3 Soiling, Grassing and Turfing 636.4 Embankments and Cuttings 63-64

6.5 Dispersal of Standing Water 646.6 Excavations Within Proposed Highway Limits 646.7 Ground Improvement 64-666.8 Granular Fill 66-68

7. ROADWORKS - OVERALL REQUIREMENTS7.1 Horizontal Alignment, Surface Levels, Layer Thicknesses and Surface

Regularity69-70

7.2 Compaction of Bituminous Materials 70-727.3 Cold Weather Working 727.4 Use of Surface by Constructional Plant 727.5 Rectification 72

8. SUB-BASE8.1 Type 1 Aggregate for Sub-Base 73-758.2 Plate Bearing Tests 76

9. FLEXIBLE SURFACINGGeneral 77

9.1 Dense Binder Course 779.2 Tack Coat 779.3 Close Graded Surface Course for carriageways 779.4 Dense Surface Course for footways 779.5 Rolled Asphalt Surface Course 779.6 Coated Chippings 78

9.7 Joints in Bituminous Construction 789.8 Recycled Material 789.9 Residual Binder Penetration 799.10 Coloured Surfacing for Conservation Areas and Other Environmentally

Sensitive Areas79

9.11 Thin Surface Course Systems 799.12 Annex B BS EN 13108-1 Asphaltic Concrete - Specification 80-889.13 Annex C BS EN 13108-4 Hot Rolled Asphalt - Specification 89-93

10. SMALL BLOCK PAVERS, KERBS, CHANNELS AND EDGINGS10.1 Kerbs, Channels and Edgings (Standard) 9410.2 Small Block Pavers: Concrete Block Paving 9410.3 Small Block Pavers: Clay Pavers 94-95

10.4 Small Block Pavers: Laying Course 95

11. CULVERTS AND SMALL RETAINING WALLSGeneral 96

11.1 Design and Technical Approval Requirements 9611.2 Specification 9611.3 Basic Design Principles 96-9711.4 Design Guidance 97

12. CONCRETE12.1 Concrete Mixes 9812.2 Cold Weather Working 9912.3 Transport and Placing 99

12.4 Compaction of Concrete 9912.5 Curing of Concrete 99

13. BRICKWORK


6/162


Clause Page No13.1 Brickwork: General 10013.2 Exposed Joints (i) Pointed Joints

(ii) Unpointed Joints100100

13.3 Cold Weather Working 10013.4 Facing Brickwork 100

14. STREET LIGHTING14.1 Approval 10114.2 Services 10114.3 Standards 10114.4 Installation 10114.5 Completion and Commissioning Maintenance 101-10214.6 Commuted Sums 102

15. PLANTING15.1 Planting Within Verges 10315.2 Trees 10315.3 Tree Planting Detail (Figure 15/3) 104

16. INDUSTRIAL DEVELOPMENT ROAD LAYOUT PARAMETERS16.1 Heavy Industrial Estate Road 105

17. PUBLICATIONS17.1 British Standards 106-10717.2 Other Publications 108-109

18. APPENDICESTitle page 110

18.1 Appendix 1 Key Construction and Inspection Stage Certificates 111-152Appendix 2 Section 38 Highway and Drainage Design Check 153-156


7/162


GENERAL GUIDANCE NOTES

INTRODUCTION

Local Authorities, other bodies or persons developing land involving the construction of Development

Roads and streets must apply in writing to the Highway Authority prior to undertaking the work, andthereafter comply in full with the requirements of this document. Any variations that may be requiredby or agreed with the Highway Authority shall be in writing. Attention is drawn to Appendix 2, Section38 Highway and Drainage Design Check. This lists the essential information required to enable aSection 38 Agreement to be processed.

PLANNING PERMISSION

Before making application to the Highway Authority, the Developer should first obtain planningpermission from the District Council concerned for the proposal as a whole. Application for this, orapproval of reserved matters in the case where an outline planning permission has already beengranted, must be made to the District Council on the appropriate form obtainable from the District

Council Offices.

The Planning Authority will need to be satisfied before granting planning permission for developmentinvolving the construction of roads, that those roads will be laid out, constructed, drained, lit, markedand signed in such a manner that they can be taken over by the Highway Authority for maintenanceat the public expense. Prospective developers are advised, therefore, to consult the HighwayAuthority, if in doubt, when preparing application drawings for submission to the Planning Authority.

A Developer must ensure that the proposal as a whole also meets requirements under any otherlegislation administered by the relevant District Council, or Lincoln City Council.

ROAD LAYOUT

The general layout and design of the new roads shall comply with the Lincolnshire Design Guide forResidential Areas.

VERTICAL ALIGNMENT

The minimum longitudinal fall for highways, without channel blocks should be 1 in 150, and withchannel blocks 1 in 250 (see Clause 10.1).

In addition developers shall ensure that the first section of any side road falls away from the road it isconnecting to. If general topography requires it to rise, this change of direction should take placeafter the first set of gullies. This is to ensure a 'false channel' with associated drainage problems isnot created in the bellmouth of junctions. See Figure 1/2.

DISPOSAL OF ROAD SURFACE WATER

The normal process for the drainage of developments is that the Developer enters into an agreementwith the appropriate sewerage undertaker under Section 104 of the Water Industry Act 1991 for thedesign and construction of the foul and surface water sewers, which are ultimately adopted by thesewerage undertaker as public sewers. The Highway Authority in these circumstances normally onlyadopts the road gullies and the connections to the surface water sewer.

When a developer is considering using highway only drainage infrastructure on a development theHighway Authority must be contacted at an early stage to determine the principles that the HighwayAuthority is likely to agree to prior to commencing any detailed design for a particular site.

Prospective Developers must establish that road surface water can be disposed of satisfactorily by

means of an outfall approved by the Highway Authority, also establishing that they have the legalcapacity to make such provision and to secure any necessary easement for the Highway Authority.


8/162


DRAWINGS

In addition to obtaining planning permission from the District Council, road constructional details mustbe approved in writing by the Highway Authority before any roadworks start. In the first instance, theDeveloper must provide two complete copies of the drawings and details of the proposed road orstreet as follows (and as shown illustratively on pages 125 & 126 of the Lincolnshire Design Guide for

Residential Areas):-

- Estate location to scale note less than 1:2500;

- the road, the subject of the application, to a scale not less than 1:500 including full details ofsurface and foul water drainage, street lighting proposals, carriageway markings and signsand all mains and services within the proposed highway;

- longitudinal sections including surface and foul water drainage to a horizontal scale not lessthan 1:500 and to a vertical scale of 1:100;

- typical cross sections of construction proposed and all other details in accordance with thetypical detail drawings given in this Specification;

- cross sections of the road at intervals of not greater than 30 metres and to a scale of 1:100

horizontal and 1:50 vertical where the adjoining site levels vary 0.5 metres from finishedfootway levels. The cross sections must extend to the building line of the proposedproperties;

- the following note shall be incorporated on all drawings submitted:- The specification in allrespects shall be in accordance with the current Lincolnshire Design Guide for ResidentialAreas and Development Road Specification and Construction publications in force in theCounty at the time of construction.

- upon completion and before the development is entered into the maintenance period, thedeveloper shall carry out an as built drainage and carriageway level survey and provide theCounty Council with as built drawings showing the as built levels plotted against the designsections to demonstrate compatibility with the design and to ensure that minimum falls areachieved.

INSPECTION, TESTING AND REPORTING

Developers are reminded of the requirement to enter into a Section 38 Agreement with theHighway Authority. Any works carried out prior to such an Agreement will not be adoptedunless the Developer can prove their acceptability by means of additional testing andinterpretive reports. In such cases the County Council must ensure that construction hasbeen carried out to an acceptable standard as required by this specification.

All requirements of this document must be demonstrated to have been met. There must bedocumentary evidence of a site investigation that demonstrates all the requirements of thisspecification have been met.

Where works have not been inspected and tested, the County Council will requireretrospective investigation and reporting; as detailed in Appendix 1 at the developers cost,before an adoption agreement will be considered. If such works are found to be defective,they will be required to be replaced at the Developers expense. All additional testing costsshall be borne by the Developer. In addition, the County Council would require the developerto pay a sum to be determined by the County Council to meet possible future risk to theAuthority due to the lack of inspection, testing and certification at the correct stage. Whereworks have been carried out prior to the developer entering into a Section 38 Agreementpayment will be required before the agreement is signed.

The developers attention is drawn to the certification process which the County Council now operatesfor development roads and the requirement; in accordance with the Section 38 Agreement, to have anominated person who is responsible for managing construction and quality of the development. This


9/162


person will be responsible for notifying in good time (a minimum of 5 working days notice) andproviding facility for the authorised representative of the County Council to carry out the initialinspections and tests and obtain the subsequent certificates for the 8 key stages of construction and 2key stages of inspection as detailed below:-

Key Stage of Construction 1 Drainage Key Stage of Construction 2 Site Investigation/Formation/Earthworks/Geotextile Key Stage of Construction 3 Carriageway Sub-base Key Stage of Construction 4 Kerbing and Channelling Key Stage of Construction 5 Carriageway Binder Course Key Stage of Construction 6 Footways and Edging Key Stage of Construction 7 Block Paved Areas Key Stage of Construction 8 Carriageway Surface Course Key Stage of Construction 9 Pre-Maintenance Period Inspection Key Stage of Construction 10 Pre-Adoption Inspection

Should the developer fail to give sufficient notice (a minimum of 5 working days) and provideadequate facility for an authorised representative of the County Council to inspect test and certificatethe above key stages of construction at the correct time, the County Council will require retrospectivetesting to be carried out at the Developers expense and in addition the Developer will be required to

pay sums to the County to meet any possible future risk to the Authority due to any lack of properinspection and testing at the appropriate stages. Appendix 1 of this specification has examplecertificates and details of the inspection, testing and certification process.

PERMANENT TRAFFIC SIGNS AND ROAD MARKINGS

Where it is deemed by the Highway Authority that, in the interests of highway safety and/or requiredby regulations, traffic signs are required to be erected and/or road markings need laying, as part ofthe development Developers will have to provide them at their cost.

All traffic signs shall be designed and erected in accordance with the current Traffic SignsRegulations and General Directions, the Traffic Signs Manual and any amendments and extensionsthereof.

For Directional, informatory or warning signs with supplementary plates, a detailed drawing of thesigns face must be provided to Traffic Signs Section for approval guidance may also be given onthe required signing by this section if necessary.

All traffic signs shall have a minimum guaranteed life of not less than 7 years; this guaranteed lifemust be not less than 10 years for Class 1 or Micro prismatic materials.

Road markings shall be in accordance with BS EN 1436 and shall have the following minimumstandards of performance for a minimum period of 2 years from the date of application.

Table G/1 Performance Standards for Road Markings

Property BS EN 1436Reference

Requirement* Value

Colour Table 6 1. White

2. Yellow ClassY1, Y2

X, Y co-ordinates given

X, Y co-ordinates given

LuminanceFactor

Table 5 1. Class B22. Class B1

0.30.2

SkidResistance

Table 7 1. Class S12. Class S1

4545

Retroreflectivity Table 2 Class of RL fordry markings

1. Class R22. Class R1

10080

Retroreflectivity Table 3 Class of RL forroad markings inconditions of wetness

Class RWD No Requirement

* Note: 1 = White, 2 = Yellow


10/162


WORKS WITHIN THE PUBLIC HIGHWAY

Any necessary off site excavations carried out in the existing public highway will require permits underthe New Roads and Street Works Act (NRSWA) 1991 and/or permission under the Highways Act1980. These works will also be subjected to the notification requirements for Traffic Management Act2004. Details of these requirements and permit applications can be obtained from The Director for

Development.

Any activity that has the potential to cause delay or disruption or any works that involve breaking upthe Highway is Registerable works and must be notified.

Should the developer fail to give sufficient notice he may be required to pay a Fixed Penalty Notice(FPN). Fixed penalty notice offers the developer the opportunity to discharge any liability toconviction for a noticing offence, by payment of the penalty. However, the Highways Authority retainsthe power to take an alleged offender to the Magistrates Courts, instead of giving an FPN. Theobjectives of the FPN system are to encourage accurate and timely notices and to improve co-ordination of the works with the aim of minimising delays and disruption arising from roads andstreetworks.

Such permits and permissions will only be granted by the County Council as Highway Authority oncethe Developer has signed and completed the Section 38 Agreement. Should the developer enteronto the existing highway in advance of this, then their excavations will be considered illegalinterference with the highway and appropriate enforcement action will be instigated.

All works conducted within the public highway must be carried out and maintained to the satisfactionof the Highway Authority.


11/162


CDM REQUIREMENTS

In accordance with Regulation 20/2 of the CDM Regulations 2007, once their site is adoptedDevelopers must pass to the Highway Authority their Health and Safety file, including any as builtdrawings for any structure, i.e. culverts, highway drains and the road itself. The Developers CDM co-ordinator should ensure the Highway Authority is given this file which must include factors whichcould influence future maintenance e.g. land contamination areas, maintenance of drains and

culverts, etc.

SPECIFICATIONS, CODES OF PRACTICES ETC

References made to Specifications, Codes of Practices, etc are current at the time of publication.Where any are superseded by new documents reference shall be made to the most up-to-dateedition.

COMMUTED MAINTENANCE PAYMENTS

In the event of Developers proposing alternative materials and features to those detailed in thisspecification attention is drawn to Clause 1.1.18. Such materials and features are often moreexpensive to replace and or have a shorter lifespan than those specified. In view of this the HighwayAuthority makes a charge to cover the additional maintenance costs for such materials and features.


12/162


1. CONSTRUCTION STANDARDS

1.1 GENERAL PRINCIPLES

1.1.1 Conformity of Standards

The construction methods, materials and standards adopted shall conform with the followingexcept where varied by this specification:-

(i) The relevant British (and relevant European) Standard specification(ii) The Highways Agencys current Specification for Highway Works(iii) TRL Laboratory Report 1132 - The Structural Design of Bituminous Roads(iv) The Highways Agencys current Pavement Design and Maintenance Manual

(Volume 7)(v) Lincolnshire County Council Highways and Planning Directorate Code of Practice -

Highway Works: Standards, Materials, Testing - HT/14/1/94.

1.1.2 Variation of Approved Details

Details shall be to the satisfaction of the Highway Authority and any variation from the detailsapproved must be communicated in writing and agreed in writing prior to the variation workbeing undertaken.

1.1.3 Construction Charts

Construction Charts 1, 2 and 3 shall be used for Housing Development Roads carrying up to0.25 million standard axles (m.s.a.). Construction Charts 4, 5 and 6 shall be used forHousing Development Roads carrying between 0.25 m.s.a. and 2.0 m.s.a. and all LightIndustrial Roads. The charts set out minimum standards of carriageway construction relatedto the bearing capacity of the sub-grade (CBR) and the weight and volume of the traffic usingthe particular road.

1.1.4 Roads Carrying Over 2.0 m.s.a.

The requirements of this specification apply to all Development Roads. Those intended toserve anticipated traffic categories in excess of 2.0 m.s.a. over a 40 year lifespan will requireindividual carriageway designs using the principles incorporated in TRL Laboratory Report1132 or the Highways Agencys current Pavement Design Manual (Volume 7). In theseinstances the Construction Charts in this specification are superseded. The materials to beused remain those detailed in this specification.

1.1.5 Concrete Roads

The construction charts do not include concrete roads and unless the Developer can produce

overriding reasons for their use, they will not normally be permitted. If instances do arisewhere concrete construction is to be used, the design must be in accordance with theHighways Agencys current Pavement Design and Maintenance Manual (Volume 7). Thedesign must be approved in writing prior to construction commencing and due to the amountof supervision and quality control tests necessary in the use of concrete, the HighwayAuthority will levy an additional supervision charge on an actual cost basis. The surface ofany such concrete road shall be bituminous surface course, the details of which shall beapproved by the Highway Authority in advance of construction commencing.

1.1.6 Site Investigation

It is important that the site investigations carried out are adequate in extent and quality. Thesite investigation must be in accordance with BS 5930 : 1999 and where appropriateBS10175:2001. The following items must be included within the report together with anyother relevant information and an interpretative section.


13/162


a) The proposed works covered by the report; i.e. highway design,

b) Site Description; to include descriptions of topography, boundaries, access,vegetation, water features, ditches, the presence of any structures or anything elsewhich may be of importance to the future use of the site.

c) Geology; a prediction of the sites geology which includes reference to BritishGeological Survey publications. In the section of the report which discusses thefindings, a cross reference to the predicted site geology and found site geology mustbe made. All exploratory hole logs must summarise the interpreted geology for eachstratum.

d) History; where there is evidence that a site has been subject to pre-development orhas become derelict, reference to present and past Ordnance Survey maps will bedeemed necessary. Other undeveloped sites may not warrant such investigation,unless subsequent intrusive work reveals evidence of previous development.

e) Site Work; details of exploratory holes and/or trial pits excavated at the site.Exploratory holes should normally be spaced between 50m and 100m adjacent to theline of the proposed carriageway and encounter all the soil types on the site.Sufficient samples of each soil type must be taken from appropriate depths andtested at the relevant natural moisture content. For CBR testing, samples must betaken from the anticipated formation level to 0.5m below, except where there aredifferent soil types when the weakest material must be sampled and tested. In-situand laboratory testing should be undertaken as appropriate. Additional exploratoryholes should be undertaken where ground conditions are variable; particularly wherethey are weak.

f) Made Ground/Fill; the full depth and nature of made ground or fill shall be proven.Further intrusive work may be necessary to qualify and quantify the nature of thismaterial along the line of the proposed adoptable road. Further work may benecessary in line with part h) below and Clause 1.1.11 (Contaminated Land).

If CBR tests are not undertaken during the site investigation, the CBR value shall beassumed to be below 1% and the construction thickness provided as shown onCharts 1-6. This can only be assumed to be the case if the site investigation indicatesthe ground to be suitable. Obviously costs can be saved by conducting CBR tests.

g) Laboratory Work; must include an indication of where the testing was carried outand a comment on the accreditation status for each test.

When assessing the ground for chemical content that is destructive to concrete thestandard used to assess this is BRE Special Digest 1:2005. Concrete in Aggressive

Ground. This digest classifies sites that might contain chemicals that are harmful toconcrete as Brownfield (C5.1.3) and those that are not as Greenfield. Brownfieldsites are sites or parts of sites that have had industrial development, storage ofchemicals (including farms) or deposition of waste, (including leachate) containingaggressive chemicals. When the history of the site is not know it should also beclassified as Brownfield.

h) Contamination; the site must be classified as brownfield or greenfield. Allbrownfield sites must be subject to contamination testing and an environmental riskassessment. Testing for contaminants on greenfield sites need only be carried out ifa specific reason to do so is identified. Further details are given in clause 1.1.11.

i) Infiltration Rate Testing and Soakaway designs; compliance with the requirements

of section 5 will be expected where the use of highway soakaways have previouslybeen agreed with the Authority.


14/162


The site investigation will need to include description of the testing process used, testresults, and the means of determining the infiltration rate(s). Subsequently, designcalculations and drawings will need to be submitted for approval.

1.1.7 Sub-grade

The construction charts give alternative construction treatments for localised soft spots. If

either the sub-grade or soft spots have a CBR below 1% then specialist advice is required.It may be necessary to provide sub-grade drainage or other soil strengthening techniquessuch as incorporating a geosynthetic product (Clause 6.7.1) or stabilisation (Clause 6.7.2).

The depth and type of treatment and the form of construction of the carriageway to beused must be agreed before the work commences.

A Developer may consider the use of a geosynthetic product which has two principal uses ina pavement foundation. The first is as a separator between the sub-base and sub-grade.The second is as a foundation reinforcing agent which can reduce the sub-base thicknesswith consequential economies in construction.The type of geosynthetic product to be used, its purpose and any proposed reduction in sub-base thickness must be agreed before construction commences (Clause 6.7.1).

1.1.8 California Bearing Ratio Test (CBR)

CBR samples must be recovered in conjunction with a site investigation carried out inaccordance with Clause 1.1.6. The relevant CBR compaction method is described in BS1377 (1990) Part 4 Clause 7.2.4.4 Method 5. Where more than 25% of material is retainedon the 20mm sieve, advice shall be sought from a suitably qualified engineer. The engineerwill advise the laboratory on what action to take with the material >20mm. The sample to betested is to be a representative sample taken between the anticipated formation level and0.50m below formation and should be compacted with a 2.5kg hammer and normally testedwith six 2kg surcharge weights. A CBR result for the top and bottom of the compactedsample shall be reported.

The developer shall propose Design CBR(s) based on the Laboratory CBR results and therevealed ground conditions. These shall take into account allowances for cohesive sub-grades (details below).

The proposed design CBR will be agreed by the Highway Authority in order to derive theappropriate construction thicknesses given in Charts 1 6 (pages 22 to 27). In mostinstances, the worst CBR result will be used for the site as a whole, but a sub-gradeinspection may be necessary to define where changes in design CBR values are to be used.(i.e where ground conditions change).

As cohesive (or clayey) soils are moisture susceptible, the strength of clayey sub-grades mayvary due to changes in water content before or after construction. In the absence of evidenceto the contrary the maximum acceptable design CBR on cohesive sub-grades on estateroads is 3% (up to 0.25msa Charts 1 to 3) and 2% on major estate roads (up to 2msa Charts4 to 6).

1.1.9 Carriageway Construction Thickness (Frost Susceptibility)

When CBR tests have been carried out, the thickness given in the tables may be used.Additionally, if tests show the sub-grade to be non frost susceptible, then further economies inthe thickness may be made. In such cases any proposed reduction in sub-base thicknessmust be agreed before construction commences.

For frost heave, materials shall be tested in accordance with BS 812: Part 124 as amendedby Clause 801 of the Specification for Highway Works Volume 1 May 2007 except that the

use of the silica sand and limestone filler reference specimens is not mandatory.

Materials are classified as non frost susceptible if the mean heave is 15.0mm or less.


15/162


1.1.10 Laboratory Reports and Test Results

The Highway Authority will accept reports containing test results only from UKAS AccreditedLaboratories which are specifically accredited for the tests in question. The County CouncilsMaterials Laboratory - Lincs Laboratory will offer further advice on this matter if requested todo so, and are able to carry out materials testing and consultancy work on a rechargeablebasis. Lincs Laboratory is a UKAS Accredited Laboratory (Testing No 0699).

Correspondence should be addressed to:- The Laboratory Manager, Lincs Laboratory, StGeorges Lane, Riseholme, Lincoln LN2 2LQ, telephone: (01522) 530355, fax: (01522)510573 or E-mail [email protected]

1.1.11 Contaminated Land

This is any land that contains substances which, when present in sufficient quantities orconcentrations, are likely to cause harm, directly or indirectly to man, to the environment or onoccasions to other targets. In the event of the Developer or any individual working on theDevelopers behalf encountering or having suspicion of encountering contaminated ground,the Highway Authority shall be informed at the earliest opportunity. Any contaminated land

encountered will need to be investigated and reported in accordance with Clause 1.1.6.This is relevant for all previously developed sites and filled sites.

A Stage 1 Environmental Desk Top Study shall be undertaken if there is any suspicion ofcontamination. This will include an assessment of the following:i) history of past useii) visible signs of contamination or dumpingiii) local and other information revealed about the siteRisk of harm will be assessed using the source-pathway-receptor model.

If the Desk Top Study identifies significant risk of harm to the construction, environment,workforce, visitors, and end users then a Quantitative Environmental Risk Assessment,which includes relevant testing for contamination, shall be undertaken.

The action to be taken from this quantitative assessment of risk will be:

i) Little or no risk no action.ii) Significant or real risk some action to mitigate or reduce risk.iii) Very significant or serious risk action to remove the hazard or pathway.iv) Highly significant or very serious risk removal of hazard will take priority over

construction considerations.

1.1.12 Plate Bearing Tests

It is important that unbound granular materials are not segregated and are adequatelycompacted. Attention is specifically drawn to Clause 8.1. The Highway Authority will carryout Plate Bearing Tests or Light Drop Weight Tests to ensure compliance with this

requirement.

1.1.13 Approved Suppliers, Test Methods and Working Standards

All materials shall be obtained from a source currently approved by the Highway Authority.The current list of suppliers is maintained by Lincs Laboratory and can be accessed viahttp://microsites.lincolnshire.gov.uk/LincsLab/section.asp?catId=3220. Developers areadvised to ensure that contractors working on their behalf are experienced in working to thestandards required by the Highway Authority.Prior to conducting tests on behalf of the Developer, the Test House shall submit details ofthe Test Procedure to be used to the Lincs Laboratory. Testing shall not take place until theTest House has received approval for the proposed Test Procedure.

Developers are required to inform the Highway Authority of proposed material suppliers andsources and sub-contractors to be used, prior to the commencement of any such elements ofwork being conducted.


16/162


1.1.14 Trafficking of Binder Course

The Developers attention is specifically drawn to the effect of trafficking exposed bindercourse materials prior to the application of the final surface course. The binder course shallbe thoroughly cleaned and a tack coat to Clause 9.2 applied prior to the laying of the surfacecourse. It may be necessary to use high pressure washing equipment if heavy contaminationhas occurred. Prolonged exposure to trafficking may result in the binder course becoming so

adversely affected that its replacement will be necessary prior to laying the surface course.The use of sealing grit to BS EN 13108-1 and Annex B of this specification to protect thebinder course if it is likely to be significantly trafficked is permissible. All traces of sealing gritshall be removed prior to the application of the surface course.

1.1.15 Trafficking of Roads, Contamination and Storage of Material

Traffic in connection with the related housing/building development must not use roads untilconstructed to the requirements of this specification. It is important that materials used in theconstruction of the areas to be adopted are not contaminated. Control should be such thatonly vehicles and plant associated with the roadworks be allowed to traffic the formation leveland sub-base layers before and during construction. Formation that is damaged and sub-base that becomes contaminated by materials used in adjoining building works, top soil, clay,

etc will not be adopted. At no stage during the construction of carriageways shall materialsassociated with the adjoining building works be stored thereon.

1.1.16 Kerbing

Kerbs shall be installed prior to the full depth of the carriageway binder course beingplaced, unless the alternative working practice detailed below is employed followingagreement, in advance, with the Highway Authority.

The Developers attention is drawn to the need to protect laid lengths of kerbing, channelsand edgings. It may be necessary for this protection to take the form of a physical barriersuch as concrete over protection with a polythene or geotextile membrane.

All damaged kerbs, channels and edgings shall be replaced prior to the application ofcarriageway or footway final surface course. Where more than 4 separate kerbs, channelsor edgings are damaged within any 10m length, the entire 10m length must bereplaced, using undamaged kerbs, channels or edgings in accordance with the specification.

Where it becomes necessary to replace kerbing, channels or edgings damaged following theapplication of final surface course to footway or carriageway, a minimum 2m length of SurfaceCourse, full width of the footway, shall be replaced. If damage is caused to the adjacentcarriageway surface course the surface course shall be replaced for a minimum of 5m for halfthe width of the carriageway. This Clause shall also apply where the Developer wishes tomake minor changes to laid kerbing e.g. when adjusting the position of a vehicular crossing.

The kerb/channel bed, on development roads shall, always be laid separate to the backing asshown on the typical sections through carriageway edge details; drawings 2.1, 2.2, 2.5, 2.6and 2.7. This is due to the high level of kerb damage experienced on development roads andthe resulting need to replace kerbs at a late stage of construction whilst causing the minimumdamage to the overall construction. In addition should the alternative kerb installationmethods below be employed then the separate kerb bed/race can be utilised as level controlfor the first layer of binder course.

For roads constructed in accordance with Construction Chart 1 the alternative method ofkerb installation (two stage construction; kerbing to be laid at a later stage) is as follows:-

The initial layer of binder course shall be 70mm thick.

Kerbing to be installed prior to laying a further 60mm layer of binder course and the 40mm ofsurface course.

Kerb bed/race laid prior to initial layer of binder course to assist with level control.


17/162


Where the CBR of the sub-grade is less than 1% specialist advice must be sought inaccordance with Clause 1.1.6, with a bespoke design being employed. Lincs Laboratory shallbe consulted in these circumstances.

The alternative kerb installation method (two stage construction kerbing to be laid at

a later stage) for roads constructed in accordance with Construction Charts 2, 4 and 5 is asfollows:-

Any appropriate combination of binder course layer thicknesses in accordance with thisSpecification may be used providing:-

The initial binder course layer shall not be thinner than 110mm.

All subsequent layers of binder course must be at least 60mm thick with at least one 60mmlayer being placed after the installation of the kerbing.

The overall specified thickness of binder course shall be increased by 10mm.

Where the CBR of the sub-grade is less than 1% specialist advice must be sought inaccordance with Clause 1.1.6, with a bespoke design being employed. Lincs Laboratory shallbe consulted in these circumstances.

Should a Developer wish to employ an alternative method of kerb installation as detailedabove, this should be shown on the typical sections and drawings submitted for approvaldetailing the construction details and processes to be employed and the combination of layerthicknesses to be used. Particular account, by the Developer, shall also be made of thefollowing points:-

Additional construction layer interfaces are being introduced and attention is drawn to therequirement to achieve bond between all bituminous layers in accordance with Clause 7.2.

Attention is drawn to the general requirement for all carriageway binder course to be 40/60grade material in accordance with Clause 9.1.

Attention is also drawn to the requirements of Clause 7.4, in that constructional plant shall besuitable in relation to the thickness of the pavement course to be traversed so that damage tothe pavement course of the carriageway or the sub-grade material is not caused. The firstlayer of binder course must not be damaged or over stressed by construction plant.

1.1.17 Minimum Depth Flexible Construction

Charts 2 and 5 provide alternative flexible designs based on the principle of replacing someof the granular foundation with bituminous material, known as bituminous replacement.Highway construction practice on these thin foundations will have to be reviewed, normalprocedures may not be appropriate due to the reduced ability of the foundation to carryconstruction traffic e.g. tracked rather than wheeled pavers to lay the binder course.Construction must be phased such that any excavated area is covered the same day withsub-base and this protected to prevent the ingress of water.

The sub-base shall conform with Clause 8.1 and shall be Type 1. Since part of the normalgranular foundation has been replaced with bituminous material the in-situ CBR requirementon top of the sub-base is not appropriate. Instead the sub-base shall comply with the in-situdensity requirement stated in Clause 8.1. This sub-base layer is not designed to carry otherconstruction traffic.

When the sub-grade CBR is 3% or less consideration should be given at the site investigation

stage to incorporate a geosynthetic separator at the sub-grade/sub-base interface. Minimumdepth flexible construction is not permitted on any site where the site investigation hasidentified a risk from soil shrinkage and heave.


18/162


The two design charts provide for frost protection when the sub-grade is classified as frostsusceptible. Additional bituminous material has been included to provide the protectionrather than increasing the thickness of non-frost susceptible Type 1 sub-base as in thenormal flexible charts. Research has revealed that dense bituminous material offers addedprotection due to its increased insulating effect and by limiting water penetration into thepavement structure.

1.1.18 Commuted Maintenance Payments

Alternative materials and features to those detailed in this specification are often moreexpensive to replace or have a shorter service life to those specified.

The additional costs associated with assessing such alternatives, including testing,will normally be borne by the proposer and the County Council will require certaincommuted sums to be paid by the developer for additional maintenance costs asfollows:-

i) Surface Water Drainage Systems including Soakaways and SustainableDrainage Systems (SuDS)

Normally, developers enter into Section 104 Agreements (of the Water Industry Act1991) with the sewerage undertaker for the design and construction of the foul andsurface water sewers, which are ultimately adopted by the sewerage undertaker aspublic sewers. The Highway Authority in these circumstances normally only adoptsthe road gullies and the connections to the surface water sewer. This is reflected inthe RSG which does not account for costs incurred from the adoption of highway onlydrainage infrastructure.

Therefore, where the Highway Authority is to adopt highway only drainageinfrastructure, the developer will be required to pay a commuted sum for maintenanceof the entire system other than the gullies and connections. This is also the case inthe circumstances where soakaways and SuDS are considered for adoption.

For clarity, the Highway Authority will not consider for adoption any systems whichcollect roof, cartilage water and/or land drainage.

ii) Non-Standard Surfacing and alternative materials.

Where materials that are not within the current specification adopted by the HighwayAuthority are used in surfaced areas, a commuted sum for maintenance will berequired.

iii) Structures and other extra over items

Highway structures (retaining walls, culvers, bridges etc), public transportinfrasturture, landscaping, trees and shrubs, and special features such as noisefencing are considered as extra over standard adoptable works. These will requirecommuted sums for their maintenance costs.

iv) Street lighting, street furniture, traffic signals and signs

Where the developer requires installations, finishings, materials, features etc., whichwould incur additional maintenance or replacement costs (when compared with thoserequired by the Highqwy Authoritys current specification), a commuted sum for theadditional maintenance cost will be required.

v) Structures

Areas of construction, grass etc which are not required in the opinion of the Highway


19/162


Authority for the safe and satisfactory functioning of the highway will require thepayment of a commuted sum for maintenance where they are being adopted.

Examples include verge outside visibility splays, areas of construction outside anormal turning head etc.

Where items, as listed above, in this clause are proposed, the developer will beinformed that a commuted maintenance payment will be written into the Section 38Agreement.


20/162


Geotextile

Topsoilbelowseededverge

RoadGulley

SurfaceWaterSewer-WaterAuthority

HighwayDrain-LincolnshireCountyCouncil

FootwayGu

lley

FoulWaterSewer-WaterAuthority

Subbase

Bindercourse

SurfaceCourse

1in40

1in40

1in250

1in150

1in25

ChannelBlock/Kerb

jointstobe

staggeredon

straights.

FIGURE 1/1 - GENERAL SECTIONAL DETAIL(NB REFER TO SPECIFIC DETAILED SPECIFICATIONS)

1in30

See Drawing Ref Clause1.6(a) for detail


21/162


1.2 SUB-BASE

Sub-base shall conform with Clause 8.1 and shall be Type 1. A minimum in-situ CBR valueof 20% will be required on all roads except for Development Roads intended to serve heaviertraffic categories (i.e. loading in excess of 0.25 m.s.a.) where the in-situ CBR value should beat least 30%. CBR values shall be determined by Plate Bearing Tests in accordance withClause 8.2.

For carriageways and footways, not more than one in ten field dry density determination, asdetailed in BS 1377:Part 9, (clause 2.2) shall be less than 90% of the maximum dry densityfor that particular sub-base as determined by the vibrating hammer test in BS EN 13286-4.

1.3 BINDER COURSE

For carriageways, Binder Course materials shall be 20mm size recipe mix Dense BinderCourse (AC 20 Dense bin 40/60 rec) to Clause 9.1 and shall be laid in a single layer orcombination of layers not less than 50mm in thickness nor greater than 110mm in thickness.Compaction must be in accordance with Clause 7.2 to a void content within the range 2%-8%and all layers must be bonded together.

1.4 SURFACE COURSE

For Charts 1 and 2 the Surface Course shall be 40mm of 10mm size Close Graded SurfaceCourse (AC 10 close surf 100/150) to Clause 7.3. It must be compacted in accordance withClause 7.2 to a void content within the range 2%-10%.

For Charts 4 and 5 the Surface Course must be 40mm of Hot Rolled Asphalt (HRA 30/14Fsurf 40/60 des) to Clause 9.5 to a void content within the range 2%-6%. Exceptionally 40mmof a Lincolnshire County Council approved thin surface course system may be used in placeof hot rolled asphalt. The Developer must obtain the agreement of the Highway Authority forthe use of the particular thin surface course system at an early stage.

The Surface Course must be bonded to the Binder Course.

1.5 FOOTWAY CONSTRUCTION

This shall comprise:-

a) Bituminous Surfacing

100mm of Type 1 sub-base to Clause 1.2

100mm of 20mm size Dense 40/60 or 100/150 Binder Course (AC 20 Dense bin rec) toClause 9.1 compacted to a void content within the range 2%-10%.

25mm of 6mm size Dense 100/150 or 160/220 Surface Course (AC 6 close surf) to Clause9.4 compacted to a void content within the range 2%-10%.

The Surface Course must be bonded to the Binder Course.

b) Block Paved Footways

100mm of Type 1 sub-base to Clause 1.2.

60mmof 20mm Dense Binder Course (AC 20 Dense bin 40/60 or 100/150 rec) to clause 9.1compacted to a void content within the range 2% - 10%.

30mm laying course of bedding sand to Clause 10.4.

60mm small unit block pavers to Clause 10.2 or 10.3. Jointing sand shall be to Clause 10.4.

Block paved footways are only permitted where the adjacent carriageway is constructed withblock pavers to Chart 3 or Chart 6.


22/162


FIGURE 1/2 - JUNCTION DETAIL WITH EXISTING CARRIAGEWAY

"R"

Tactile paving

Kerbs to be dropped at intersection withfootway to 25mm upstand or flush where

tactile paving required

Side road junction to fall away from the main

carriageway

Gully

Design to ensure a minimum fall along the channel of 1 in 250 wherechannel blocks are used or 1 in 150 where channel blocks are not used


23/162


ST3

Concrete

380

150

150

150mm

min.

125x150DroppedKerb

Gra d

ie n

t1

in

25

1 1 0110

SectionA:A

SeeCla

use1.6

MortarBed

Gradie

ntto

be

1i

n3

0

2.4

m

MinimumStandards

3Droppedkerbsforasingle

crossing

7Droppedkerbsforapaired

crossing

Fornarrowroadsorwheregeometrydictates4

ormorekerbswillbereq

uired

A

A

Gradie

ntto

be

1i

n2

5

Min6.0m

FIGURE 1/3 - DOMESTIC VEHICLE CROSSING(REF. CLAUSE 1.6(A))

25


24/162


Wid

thVaries

1in25

Highway Boundary

"R"

125 x 255 P.C. Concrete Channel

Blocks if restraint not otherwise present

Kerb tops and channel blocks flush at

this point

Verges may be ommitted

125 x 255 P.C. Concrete Channel

Blocks required if installed along

adjacent carriagewayand/or adjacent

carriageway is not surfaced with hot

rolled asphalt

P.C. Concrete kerbs laid to radius "R"

as specified by planning condition

Tactile paving

All Dimensions given in mm.

Kerbs to be dropped at intersection with

footway to 25mm upstand or flush if tactile

paving required

FIGURE 1/4 - HEAVY DUTY VEHICLE ACCESS CROSSING(Ref Clause 1.6(a))


25/162


1.6 VEHICLE ACCESS CROSSINGS

(A) Light Duty (Domestic) crossings

150mm of Type 1 sub-base to Clause 1.2. (NB where the CBR value of the sub-grade is below 2% an approved geosynthetic layer to Clause 6.7 will be required tobe placed on the sub-grade). On certain sites the depth of topsoil may exceed

275mm. On such sites topsoil containing organic matter, roots, etc. shall be removedand replaced with Type 1 sub-base in accordance with Clause 1.2.

100mm of 20mm size recipe mix Dense Asphaltic Concrete Binder Course to Clause9.1 compacted to a void content within the range 2%-10%.25mm of 6mm size Dense Asphaltic Concrete Surface Course to Clause 9.4compacted to a void content within the range 2%-10%.

The joint between the access crossing and the carriageway shall be formed with125mm x 150mm precast concrete kerbs on a 150mm x 380mm base of ST3(15N/mm) concrete (approx. 1 cement:2 sand:4 aggregate by volume mix). A125mm x 150mm x 225mm taper kerb will be required on each side of the crossingalong the carriageway edge.

The highway boundary shall be delineated across the access crossing with 50mm x150mm square cut precast concrete edging on a 75mm x 330mm base of ST3(15N/mm) concrete, and where there is no footway the edges of the access crossingshall also be delineated with the same edging and base (see Drawing Ref Clause1.6(A)).

(B) Heavy Duty Vehicle Access Crossings

The construction and thickness shall be the same as the adjacent carriageway withthe proviso that in all cases the surface course shall be hot rolled asphalt to Clause1.4. Radii kerbing shall be used each side of the crossing, dropped at the point ofintersection with adjacent footways and tactile paving shall be provided each sidewhen required (see Drawing Ref Clause1.6 (a).

Channel blocks, not dropped kerbs shall be used at the front of these crossings ifchannel blocks are installed along the adjacent carriageway and/or the adjacentcarriageway is not surfaced with hot rolled asphalt. Channel blocks shall be installedat the rear of such crossings unless alternative restraint is available.

(C) Small Block Pavers

Small unit paver construction will be permitted for access crossings only when theadjoining footway is of that construction type. The materials utilised and thicknessemployed in the crossings shall be the same as the adjoining carriageway.

1.7 WAITING BAY OR LAY-BY CONSTRUCTION

Construction shall normally be as for the adjoining carriageway.

1.8 TACTILE PAVING CROSSINGS FOR PEDESTRIANS

Blister tactile paving crossing points shall be provided at all junctions, crossings at linkfootways and at kerb to kerb flat top road crossings.

Tactile paving shall be Dimple blocks, either 450mm x 450mm x 50mm, 400mm x 400mm x

50mm or dimpled 100mm x 200mm x 60mm paving blocks. The surface colour shall be buff.


26/162


FIGURE 1/5 - DROPPED KERB DETAIL PRIOR TO INSTALLATIONOF BLISTER SURFACE

Rear of footwayStandard kerb

Taper/dropper kerb

Central channel blocks min1.8m to be flush with

carriageway surface

To enable standard dropper kerbto be used a larger joint may be

necessary for kerbs be flush with

the carriageway as specified

Kerb Carriageway

Footway

Variable width as specified but must notbe less than that required to achieve a

maximum gradient of 8% (1:12)

Preferred carriageway surface level

Minimum carriageway surface level

Footway

Notgreaterthan6mm


27/162


FIGURE 1/6 - USE OF TACTILE PAVING AT PEDESTRIANCROSSING POINTS

6m

radiu

s

FLAT TOP HUMP

1.8m

CROSSING POINT AT RAISED PLATFORM

CROSSING POINT AT LINK FOOTWAY

1.2m

min

1.2mm

in

1.2m min

450 x 450 Tactile

slabs

UNCONTROLLED CROSSING POINT ATJUNCTION

6mradius

UNCONTROLLED CROSSING AWAY FROM

JUNCTION

800mm


28/162


Tactile paving shall be installed in the line of travel, along the full length of a minimum of 1.6mflush dropped channel blocks. Flush kerbs to comprise 152mm x 152mm precast concretechannel blocks. The depth of the paving will be at least 1.6m or 400mm depending on itslocation (see drawings on page 17). The back edge of the tactile paving surface shall be atright angles to the direction of crossing

Developers shall take care not to locate service boxes (e.g. BT) where tactile paving isrequired.

1.9 SMALL BLOCK PAVERS

Concrete blocks and clay pavers shall comply with Clause 10.2 and 10.3. They shall be laidin accordance with the requirements of BS 7533-3.

Herringbone bond pattern is required for all block paved areas. Only rectangular shapedblocks will be permitted.

The layout of blocks/pavers and details at edges, manholes, gullies and other openingsshall be as recommended by the supplier and agreed with the Highway Authority in

advance of laying.

The developer may traffic the carriageway after the placement of the bituminous bindercourse across the full width of the carriageway provided that the thickness of the bindercourse is in accordance with the relevant Construction Chart.

When the block paver construction is to be completed prior to building being commencedthen the thickness of the binder course layer quoted in Construction Chart 3 for roads up to0.25 m.s.a. may be reduced to 60mm. The sub-base shall be correspondingly increased by30mm in such cases.

Laying course (bedding) and jointing sand used in conjunction with small block pavers shallbe in accordance with Clause 10.4.


29/162

Version 2.0 23

CONSTRUCTION CHART 1

ROADS UP TO 0.25 m.s.a. - NORMAL FLEXIBLE CONSTRUCTION

SUB-GRADENote 1

SUB-BASE (mm) SURFACING (mm) T

Design

CBR

Without

geosynthetic

With

geosynthetic

Binder Course Surface Course

Below 1% & soft spots1%2%3%4%

Note 7

5%Note 7

6-15%Note 7

Above 15%Note 7

Not suitableNot suitable

400310300300300300

710Notes 2&3

440

340300300

Note7

300Note 7

300Note 7

300Note 7

Notes 4&5110110110110110110110110

4040404040404040

Note 1 See Clauses 1.1.6, 1.1.7 and 1.1.8Note 2 See Clause 1.1.6 Assumes no improvement is possible using either sub-soil drainage or soi

410mm of 6F5 Capping Layer Granular Fill to clause 6.8 and 300mm of Type 1 sub-base. Theto 620mm if all Type 1 sub-base is used.

Note 3 For soft spots and sub-grades with a CBR of less than 1% the geosythetic shall be an approNote 4 May be laid in one layer.Note 5 Initial Binder Course layer thickness 70mm if the alternative kerbing installation method (tw

laid at a later stage) is used. Total Binder Course thicknessbecomes 130mm in these circuNote 6 Total thickness to be increased by 20mm above these values if the alternative kerbing insta

See Clause 1.1.17.Note 7 The use of a geosynthetic with a sub-grade with this bearing capacity offers no advantage or e


30/162

Version 2.0 24


ROADS UP TO 0.25 m.s.a. - MINIMUM DEPTH FLEXIBLE CONSTRUCTION(See Clause 1.1.18)

SUB-GRADENote 1

SUB-BASE (mm) SURFACING

DesignCBR

Non-frostsusceptible

Type 1Binder Course Surface Course

Below 1% & soft spots1%2%3%4%5%

6-15%

Above 15%

Note 2Note 2

150150150150150

150

Note 3200200200200200200200

200

40404040404040

40

Note 1 See Clauses 1.1.6, 1.1.7 and 1.1.8Note 2 See Clauses 1.1.6 & 1.1.18

Requires at least 150mm Type 1 Sub-Base plus an approved sub-soil strengthening techniqueNote 3 Initial Binder Course layer thickness 110mm if the alternative kerbing installation method (t

laid at a later stage) is used. This may be laid in one layer. The total thickness of Binder Cocircumstances. See Clause 1.1.17.

Note 4 Initial Binder Course layer thickness 110mm if the alternative kerbing installation method islayer. The total thickness of binder course becomes 200mm in these circumstances. See Cla

Note 5 Alternative kerbing installation method not appropriate in these circumstances.Note 6 Total thicknesses becomes 400mm if alternative kerbing installation method used.


31/162


32/162

Version 2.0 26


ROADS UP TO 2.0 m.s.a. - NORMAL FLEXIBLE CONSTRUCTION

SUB-GRADENote 1

SUB-BASE (mm) SURFACING (mm) TOTAL TH

Design

CBR

Without

geosynthetic

With

geosynthetic

Binder

Course

Surface

Course

Withou

geosynthe


Note 6

5%Note 6

6-15%Note 6

Above 15%Note 6

Not suitableNot suitable

400310260230230230

710Notes 2&3

440340300260

Note6

230Note 6

230Note 6

230Note 6

Note 4180180180180180180180180

4040404040404040

Not suitabNot suitab

620N

530N

480N

450N

450N

450N

Note 1 See Clauses 1.1.6, 1.1.7 and 1.1.8Note 2 See Clause 1.1.6 - Assumes no improvement is possible using either sub-soil drainage or soil


Note 3 For soft spots and sub-grades with a CBR of less than 1% the geosythetic shall be an approNote 4 Initial Binder Course layer thickness 110mm if the alternative kerbing installation method (t

laid at a later stage) is used. This may be laid in one layer. The total thickness of Binder Cocircumstances. See Clause 1.1.17.

Note 5 Total thickness increased by 10mm above these values if the alternative kerbing installatioSee Clause 1.1.17.

Note 6 The use of a geosynthetic with a sub-grade with this bearing capacity offers no advantage or e


33/162

Version 2.0 27


ROADS UP TO 2.0 m.s.a. - MINIMUM DEPTH FLEXIBLE CONSTRUCTION(See Clause 1.1.18)

SUB-GRADENote 1

SUB-BASE (mm) SURFACING (mm)

DesignCBR

Non-frostsusceptible

Type 1Binder Course Surface Course W

Below 1% & softspots1%2%3%4%5%

6-15%Above 15%

Note 2Note 2

150150150150150

150

Note 3260260260230220210200

200

40404040404040

40

Note 1 See Clauses 1.1.6, 1.1.7 and 1.1.8Note 2 See Clause 1.1.6

Requires at least 150mm Type 1 Sub-Base plus an approved sub-soil improvement techniqueNote 3 Initial Binder Course layer thickness 110mm if the alternative kerbing installation method (t

laid at a later stage) is used. This may be laid in one layer.The total thickness of Binder Course is increased by 10mm in these circumstances. See

Note 4 Total thickness increased by 10mm above these values if the alternative kerbing installatioSee Clause 1.1.17.


34/162

Version 2.0 28


ROADS UP TO 2.0 m.s.a. - BLOCK PAVER CONSTRUCTION

SUB-GRADENote 1

SUB-BASE (mm) SURFACING (mm) TO

Bearing

Capacity(CBR)

Without

geosynthetic

With

geosynthetic

Binder Course Laying

Course

Block

Paver g


Note 4

5%Note 4

6-15%Note 4

Above 15%Note 4

Not SuitableNot Suitable

400310260225220220

710Note 2

440

340300260

Note4

225Note 4

220Note 4

220Note 4

120120120120120120120120

3030303030303030

8080808080808080

NN

Note 1 See Clauses 1.1.6 & 1.1.7Note 2 See Clause 1.1.6 - Assumes no improvement is possible using either sub-soil drainage or soil


Note 3 For soft spots and sub-grades with a CBR of less than 1% the geosythetic shall be an approNote 4 The use of a geosynthetic with a sub-grade with this bearing capacity offers no advantage or e

Ref: BS7533 Guide for structural design of pavements constructed with clay or concrete block


35/162

Version 2.0

28 May 2009

29

FIGURE 2/1 & 2/2 - TYPICAL SECTIONS THROUGH

CARRIAGEWAY EDGE AND FOOTWAY EDGE

2/1 CHARTS 1,2,4,& 5 Type Roads

2/2 CHART 3 & 6

330

ST3 Concrete

120

50 x 150 Precast concrete edging

Small Kerb Unit on

a mortar bed

ST3 Concrete

100

150

150

2 Rows laid in stretcher bond

Blocks laid in

herringbone bond

30mm Bedding Sandlaying course

1.8m

ST3 Concrete

120

50 x 150 Precast concrete edging

330

110

255 x 125 Precast concrete kerb

Mortar Bed150

75

380

50

FOR CARRIAGEWAY AND FOOTWAY DETAILS SEE SECTION 1 CHARTS 1 TO 6

100

150

Version 2.1 - 20/1/2009


36/162Version 2.0 28 May 200930

FIGURE 2/3 - SHARED SURFACE ROAD PLAN

RAMP

1.8m

900mm

WIDE

ACCESSTODWELLING

VEHICLE

ACCESS

PED.ACCESS

1.8m

SERVICE STRIP

1.8m

SERVICE STRIP

MAXIMUMGRADIENT

TOWARDS

CARRIAGEWAY1:12

1:25GRADIENT

TOWARDS

CARRIAGEWAY

GRASS

GRASS

700mm

1.8m

1.8m

FOOTWAY

1.8m

FOOTWAY

110mm

KERB FACE

FLUSH

KERB FACE

2 No. ROAD HUMP

MARKINGS TO DIAG.1062

25mm KERB

FACE

SHARED ROADSURFACE

25mm KERB

FACE

EDGINGS

EDGINGS

MAXIMUMGRADIENT

TOWARDS

CARRIAGEWAY1:12

EDGE OF HIGHWAY TO

BE MARKED WITH

CONTINUOUS

CONCRETE EDGINGS

NO TACTILE PAVING

REQUIRED

KEY

AREA TO BE BLOCK PAVED

AS MAIN FOOTWAY CONSTRUCTION

NOTES:

1. DIAG.557.1 ROAD SIGN TO BE

ERECTED PRIOR TO RAMP.

2. TACTILE PAVING SHOULD NOT BE

USED ON SHARED SURFACE ROAD.

A

A

A

A

140mm - AC20 Dense Bin 40/60 Rec

SUB BASESUB BASE

Top of kerb

110mm

Kerb

face

25mm mortar bed

200 x 200 x 220 Transition Blocks

150 x 125 PCC Kerb - 25mm face

RAMP DETAIL - Section A:A Transition Blocks

700mm25mm mortar bed

SUB BASESUB BASE

Top of kerb

110mm

Kerb

face

25mm mortar bed

150 x 125 PCC Channel Block

150 x 125 PCC Kerb - 25mm face

RAMP DETAIL - Section A:A Channel Blocks

700mm

25mm mortar bed

140mm - AC20 Dense Bin 40/60 Rec


37/162Version 2.0 28 May 200931

FIGURE 2/4 - SHARED SURFACE ROAD SECTION

DESIGNEDVERTICAL

ALIGNMENT

DESIGNEDVERTICAL

ALIGNMENT

TOPOFKERB

Y=1No.1/24GRADEDROPPERKERB

85mm

25mm

25mm

Y

Y

ENDOFFOOTWAY

110mm

700mm

110mm

900mmPEDESTRIAN

ACCESSTODWELLING

VEHICULARACCESS


38/162Version 2.0 28 May 200932

FIGURE 2/5 - CHANNEL BLOCK AND KERB DETAIL

255 x 125 Precast concrete kerb

FIGURE 2/6 - SERVICE MARGIN DETAIL

SHARED SURFACE

Minimum 100 topsoil and then turved

or seeded

Highway boundary marked by continuous

concrete edgings(To be installed prior to occupancy of dwellings)

Minimum 1800

Minimum 100 topsoil and then turved or

seeded

Minimum 300

FIGURE 2/5 CHANNEL BLOCK AND KERB DETAIL

250 x 125 Precast channel block

ST3 Concrete

110

Mortar Bed150

625

Alternative detail where swale drainage is used


39/162Version 2.0 28 May 200933

FIGURE 2/7 - Chart 1 Type Road Utilising AlternativeMethod Of Kerb Installation (Two stage construction;

kerbing to be added at a later stage)

FOR CARRIAGEWAY AND FOOTWAY DETAILS SEE SECTION 1 CHARTS 1 TO 6

ST3 Concrete150

15015

0

50 x 150 Precast concrete edging 255 x 125 Precast concrete kerb

ST3 Concrete

Mortar (25mm)

100

150

150

100

70Initial Binder Course

Binder course laid 50mm

wider to allow for futuretrimming to accept kerbs

STAGE 1

Kerb bed/race laid to assist

level control

STAGE 2

40mm Surface Course60mm Binder course

Laid at a later stage

70mm

Initial Binder

course

Binder course saw cut back to accept kerbs

(Sealant material to be agreed according to

width to be infilled)

1.8m

120

330

100

100

110

Version 2.1 - 20/1/2009


40/162Version 2.0 28 May 200934

3. TRAFFIC AND SAFETY MEASURES DURING CONSTURCTION

3.1 TEMPORARY TRAFFIC SIGNS

The Developer shall erect and maintain on the site and on the approaches to the site all trafficsigns and traffic control signals necessary for the direction and control of traffic. The signsshall conform to the current Safety at Street Works and Road Works Code of Practice andwhere applicable The Traffic Signs Manual Chapter 8 Traffic Safety Measures and Signs for

Roadworks and Temporary Situations. The signs shall be reflectorised and kept clean andlegible.

3.2 CONTROL OF TRAFFIC

If, during any part of the construction, it becomes necessary to restrict or interfere with the flowof traffic on the public highway, then approval and approval must be obtained from theHighway Authority. A minimum of two weeks notice will be required for such approval.Notification lead in times that may be longer are subjected to the duration of the works inaccordance with the Traffic Management Act 2004.

Where traffic signals are required, a minimum of two weeks notice is also required from theDivisional Highways Manager as above. For Trunk Roads this notice is extended to six weeks

and approval is required from the Highways Agencys Trunk Road Agent.

Three or four-way temporary signals will require separate approval by the Traffic SignalsEngineer and require a minimum of four weeks notice.

3.3 TEMPORARY DIVERSION OF TRAFFIC

The Developer shall construct temporary diversion ways wherever the works will interfere withexisting public or private roads or other ways over which there is a public or private right orway for any traffic, including pedestrians. Any diversion shall be suitable in all respects for thetype and volume of traffic requiring to use it. It shall be constructed in advance of taking upthe existing way and regularly maintained.

3.4 SAFETY CODES

The Developer shall comply with the current Safety at Street Works and Road Works Code ofPractice and where applicable The Traffic Signs Manual Chapter 8 Traffic Safety Measuresand Signs for Roadworks and Temporary Situations and all of the relevant current safetystandards.

3.5 EXCAVATIONS

The Developer shall ensure that all excavations on the site and on the approaches to the siteare adequately signed, fenced and supported.

3.6 MATERIALS ON THE HIGHWAY

No building materials etc. shall be stored on the public highway, without the permission of theHighway Authority. Care should also be taken not to impede visibility at junctions through theinappropriate storage of materials on site.

3.7 MUD, ETC., ON THE HIGHWAY

Developers are reminded that under the Highways Act 1980, they are responsible for ensuringthat the existing public highway is kept clear from mud, stones, silt, etc. at all times.

Every effort should also be made to keep sites, where dwellings are occupied, in a safe andtidy condition.


41/162Version 2.0 28 May 200935

4. SITE CLEARANCE

4.1 CLEARING SITE

Trees, stumps and tree roots within the proposed highway shall be removed. Holes left by thedemolition of buildings, by uprooting trees etc., shall be filled in accordance with Clause 5.6.


42/162Version 2.0 28 May 200936

5. DRAINAGE

5.1 GENERAL PRINCIPLES

5.1.1 The normal process for the drainage of developments is that the Developer enters into anagreement with the appropriate sewerage undertaker under Section 104 of the WaterIndustry Act 1991 for the design and construction of the foul and surface water sewers,

which are ultimately adopted by the sewerage undertaker as public sewers. The HighwayAuthority in these circumstances normally only adopts the road gullies and the connectionsto the surface water sewer.

This reflects the consideration that Government funding to Highway Authorities does notaccount for additional costs that would be incurred from the adoption of highway onlydrainage infrastructure. Also, it is not possible for Highway Authorities to demand ongoingcharges (as is the case for sewerage undertakers who charge sewerage rates) from thosewho benefit from such arrangements.

Notwithstanding the above where a developer is considering using highway onlydrainage infrastructure on a development they must contact the Highway Authority atan early stage to determine the principles that the Highway Authority is likely to agree

to prior to commencing any detailed design for a particular site.

5.1.2 In view of the above, where the Highway Authority is to adopt certain highway onlydrainage infrastructure (other than for gully connections) the developer will berequired to pay Commuted Maintenance payments calculated by the HighwayAuthority. The Highway Authority will not consider for adoption any systems whichcollect roof, curtilage water or land drainage.

The Developers attention is drawn to Clause 1.1.11 and where contaminants are presentthey are to detail their effect on the proposed highway drainage infrastructure and anypotential health risk to Highway Authority staff and their contractors during maintenanceoperations (including excavation).

The Developers attention is drawn to the list of information required to commence adrainage design check. The list is included in Appendix 2, Highway and Drainage DesignCheck. Failure to provide the information requested will delay the processing of thesubmission.

The Developer shall submit the designers risk assessments for the design, operation andmaintenance of the highway drainage system.

5.1.3 Pumping Stations and rising mains will not be considered for adoption as part of a highwaydrainage system.

5.1.4 Sustainable Drainage Systems (SuDS) and above-ground attenuation systems have beenproposed as solutions for dealing with surface water flows in environmentally friendly ways;however, the Highway Authority is generally constrained to only accepting pipe systems foradoption.

5.1.5 Should a developer wish to propose a SuDS or above-ground attenuation system solution tosurface water drainage of a development, they should contact the Highway Authority at anearly stage to discuss the likely acceptability of such proposals and any requirements andsafeguards which the Highway Authority may wish to be in place. These include:

a) highway drains should have a hydraulically free discharge into any SuDS or above-ground attenuation device;

b) above-ground attenuation devices should have a high level weir at the outlet, setbelow the invert level of the incoming highway drain;

c) adequate administrative arrangements for the future maintenance of the facility; withan appropriate authority or agency.

d) a Deed of Grant of Rights for the Highway Authority to discharge water into the SuDSor attenuation facility in perpetuity;


43/162Version 2.0 28 May 200937

e) sufficient design capacity to accommodate the requirements of Clauses 5.4.1 to 5.4.8.

5.1.6 Soakaways may be considered for adoption in exceptional circumstances but only on smallsites of less than 10 dwellings where there is no positive outfall within reasonable proximityto the site as they have a relatively short life and for the reasons stated above a commutedsum will be required.

Soakage tests and highway soakaway designs shall be in accordance with criteriastipulated by the Highway Authority.

Infiltration rate tests and highway soakaway designs shall be in accordance with the criteriastipulated by the Highway Authority and such designs shall adhere to the findings andrecommendations of an appropriate and acceptable site investigation report (clause1.1.6(i)).

Where a developer is considering soakaways in an area with a naturally high ground waterlevel they will be required to submit records of groundwater levels obtained from a reliablesource for the previous 12 months or any other period stated by the Highway Authority.

There shall be a minimum 1m clearance between the underside of the soakaway and highestground water level.

Soakaways should be located within an area to be adopted by the Highway Authority. In exceptional circumstances they may be located within an area of Public Open space thatis to be maintained by the District Council, subject, of course, to the written approval of theDistrict Council. Soakaways will not be permitted within 5 metres of building foundations,within 2 metres of the carriageway, within 1 metre of any service or area required forservices nor within areas of fill. Soakaways will not be permitted beneath the carriagewayitself. The Developers attention is drawn to the requirements of Building Regulations withregard to the location of soakaways.

5.1.7 Notwithstanding the above, any approved soakaways would need to accommodate therequirements of Clauses 5.4.1 to 5.4.8.

5.1.8 A Consent to Investigate and to Discharge licence may be required by the EnvironmentAgency for soakaways, and where this is the case, a copy of the Agreement must be givento the Highway Authority before approval is given. Details of relevant consents fordischarge and wayleave/easements must be submitted to the Highway Authority forconsideration before approval is given.

5.2 DESIGN LAYOUT

5.2.1 All highway drainage systems shall be situated within land which is to be adopted by theHighway Authority. The only exception being where the development is to drain to a remoteoutfall away from the development. In this instance, where the final outfall pipe leaves the

development, it may by agreement cross third party land and will be subject to the requiredwayleaves/easements and consents which will need to be provided to the HighwayAuthority.

Only in exceptional circumstances will elements of the highway drainage system bepermitted within an area of public open space, subject to the written approval of the DistrictCouncil. Where such circumstances do arise, the land owner (Developer) will be required toprovide a Grant of Easement giving the Highway Authority right of access at all times forrepair and maintenance purposes.

Where easements, wayleaves, consents and the like are necessary the Developer isrequired to submit a draft of any such document to the Highway Authority. Technicalapproval will not be granted until the documents have been approved. Should the

circumstances of the easements, wayleaves, consents and the like change followingapproval the Highway Authority must be notified in writing immediately. In thesecircumstance the Highway Authority reserves the right to rescind technical approval untilnew easements, wayleaves, consents and the like have been submitted and approved.

Easement details are detailed in Clause 5.2.4


44/162Version 2.0 28 May 200938

5.2.2 Manholes and sewers should be sited with due regard to public utility services. A manholeshould be built at every change of alignment or gradient; at the head of all pipe runs; atevery junction of two or more pipes (other than gully connections); wherever there is achange in the size of the pipe. Manholes should not be further apart than 100m.

5.2.3 When in a highway, the outside of the pipe should be in the vehicle carriageway (notfootway) and be at least 1m from the kerb line. The outside of manholes should be at least0.5m from the kerb line.

5.2.4 Minimum easement widths are shown in Table 5/1. Where other pipe layouts are proposedi.e dual systems, advice must be sought from the Highway Authority.

Table 5/1

Minimum distances of buildings and structures from prospective highway drains

SewerDiameter

Up to449mm

diameter450 749mm 750 - 924

925 andabove

Boxculverts,the greater

ofDepth to

invert3.0m

Seek advice Seek advice Seek advice Seek advice Seek advice

There shall be no physical obstructions or structures on, above or below the easement routewith the exception of minor services and simple fencing that may cross the route

perpendicularly.

Developers shall seek the advice of the Highway Authority when the easement is to belandscaped as there may be restrictions on layout and species allowed. This should beconsidered when the developer submits landscaping proposals with his planningapplication.

Where pipe lengths are located outside the adoptable public highway manholes andancillary structures shall be accessible by conventional sewer cleaning equipment (e.g.Large combination jetting/vacuum unit).

5.2.5 Highway drains laid within highways should have a minimum cover of 1.2m measured from

the top of the pipe barrel to the finished road surface, in order to avoid interference withother underground utility pipes and cables. Where this is not practicable, special protectivemeasures in accordance with Clause 5.13.4 will be required irrespective of pipe crushingstrengths. The design of the pipeline should take account of loading from the passage ofthe Developers construction plant, as well as normal design loading. Highway drains notlaid in the highway should be laid at a sufficient depth to avoid interference with land drainsor cultivation. Cover over the shallowest part of the pipeline structure of 0.9m wouldnormally satisfy this requirement.

5.2.6 The minimum size of highway drains to be adopted is 150mm nominal internal diameter.Pipes/conduits greater than 600mm diameter are classed as highway structures andSection 11 of this design guide applies.

5.2.7 Details of headwalls for highway drain outfalls, shall be submitted for approval by theHighway Authority. Where highway drain outfalls retain a height greater than 600mm or areof an unusual construction they are classed as highway structures and Section 11 of thisdesign guide applies.


45/162Version 2.0 28 May 200939

5.3 CONNECTIONS TO EXISTING DRAINS OR PUBLIC SEWERS

5.3.1 Before entering or breaking into an existing sewer or drain, the Developer must obtain thepermission of the Authority responsible for the pipeline to which the connection is to bemade. Where excavation within the existing public highway is necessary, the permission ofthe Highway Authority must be obtained and a permit to work in the highway under the NewRoads and Streetworks Act must be obtained from the Highway Authority. In addition to thePermit (section 50 licence) the Developer (work promoter) must give the relevant notificationfor the works under the Traffic Management Act 2004. The minimum notification periods aresubject to the duration of the works.

5.3.2 Should a developer wish to drain any part of a proposed development to an existing highwaydrainage system, the developer will be required to submit a full survey of the existing systemtogether with calculations in accordance with clauses 5.4.1 to 5.4.8 to demonstrate itssuitability to accept additional flows. Should it become necessary to improve the existinghighway drainage system within the existing public highway a separate agreement will be

development road specification and construction amended february 2009

Documents