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SPECIFICATION FOR THE REINSTATEMENT OF OPENINGS IN ROADS

SPECIFICATION

S1 Introduction

S1.1 General

This Specification incorporates new terminology which is to be used in future European standards. Readers and practitioners should make themselves familiar with the new terms, as follows:

S1.1.1 An Undertaker executing roadworks shall carry out the excavation and reinstatement in accordance with this Specification. Where this Specification allows alternatives, the Undertaker shall select one of the options allowed. Regardless of which alternative is selected, the Undertaker shall guarantee the performance of the reinstatement to the relevant standard, for the relevant guarantee period.

S1.1.2 The reinstatement shall be carried out using a permitted method incorporating the highest degree of immediate permanent reinstatement appropriate, in the opinion of the Undertaker, to the prevailing circumstances.

S1.1.3 If, at any time during a guarantee period, the reinstatement fails the relevant performance requirements of this Specification, the Undertaker shall carry out remedial action to restore the reinstatement to the as-laid condition. An interim reinstatement shall normally be made permanent within six months.

S1.1.4 The requirements and standards in this Specification apply to roads which are maintainable or prospectively maintainable at public expense. In the case of all other roads, only those relevant parts of this Specification relating to "Surround to Apparatus" and "Backfill" shall apply. Surfacing layers, if any, shall be reinstated, as far as is reasonably practicable, to match the existing construction. In all cases, reinstatement must be undertaken to the reasonable satisfaction of the Authority.

S1.2 Guarantee Period

S1.2.1 The Undertaker shall ensure that the interim reinstatement conforms to the prescribed standards until the permanent reinstatement is completed, and that the permanent reinstatement conforms to the prescribed standards throughout the guarantee period.

S1.2.2 The guarantee period shall begin on completion of the permanent reinstatement and shall run for two years, or three years in the case of deep openings. It should be noted that completion of the permanent reinstatement, rather than the giving of information to the Authority that the reinstatement is completed, is the event that triggers the start of the guarantee period. Failure to give information is an offence under Section 129 (6) of the Act.

S1.3 Road Categories

S1.3.1 Roads are categorised by this Specification into five types, each with a limiting capacity expressed in millions of standard axles (msa) as shown in Table S1.1.

Table S1.1 - Road Categories

S1.3.2 Roads carrying more than 125 msa are not included in this Specification. Reinstatement designs for such roads shall be agreed between the Undertaker and the Authority, on an individual basis.

S1.3.3 Road categories defined in Table S1.1 are based on the expected traffic to be carried by the road over the next 20 years. Each Authority shall categorise its road network on this basis and the Undertaker shall use the most current information available from the Authority. Where an Authority does not classify its roads as required by this Specification, the Undertaker shall determine the classification of all roads, as necessary, and provide a copy of the classification to all parties concerned.

S1.3.4 Valid traffic rates shall be assessed by accurately monitoring commercial vehicles in excess of 1.5 tonnes unladen weight. Traffic growth rates shall be determined from the average of at least three separate assessments carried out over at least three years. Where traffic growth rates are expected to increase significantly, as a result of changing traffic patterns, only predictions generated from a recognised planning process may be used. A zero growth rate shall be assumed until accurate information is available.

S1.3.5 The reinstatement shall be designed using materials specified in Appendices A1, A2, A9, A10 & A11. The overall layer thicknesses shall be as specified in Appendices A3 to A7 for the various categories of road, footway, footpath, cycletrack, verge or unmade ground, and shall be compacted to the requirements of S10 and Appendix A8.

S1.4 Footway, Footpath and Cycletrack Categories

Footways, footpaths and cycletracks are categorised by this Specification as follows:

S1.4.1 High duty - routes where the two way traffic flow of pedestrians and/or cyclists exceeds 22 persons per minute, per linear metre width, for at least half of the working day.

S1.4.2 High amenity - routes surfaced with one of the following materials, and which have been constructed and maintained to a high standard:

1) Modular surfaces chosen specifically for decorative purposes, with special colours, textures or surface finishes.

2) Flexible surfaces with a particular texture or distinctive coloured finish. Such surfaces will usually be situated in conservation, leisure or ornamental areas, pedestrian precincts or where an Authority has maintained high quality paving.

S1.4.3 Other - those that are neither high duty nor high amenity.

S1.5 Excavation and Trench Categories

Excavations and trenches are categorised by this Specification as follows:

S1.5.1 Small Excavations - all openings with a surface area of 2 square metres or less. For the purposes of this Specification, test holes up to 150 mm diameter are not excavations and shall be reinstated in accordance with the requirements of Section S11.

S1.5.2 Narrow Trenches - all trenches of 300 mm surface width or less, with a surface area greater than 2 square metres.

S1.5.3 Deep Openings - all excavations and trenches in which the depth of cover over the buried apparatus is greater than 1.5 metres. Trenches with a depth of cover which is intermittently more than 1.5m for lengths of less than 5 metres are deemed not to be deep openings.

S1.5.4 Other Openings - all excavations and trenches with a surface area greater than 2 square metres.

S1.6 Alternative Options

S1.6.1 An Undertaker may adopt an alternative Specification for materials, layer thicknesses and compaction methods to take advantage of new or local materials and/or alternative compaction equipment, subject to the prior agreement of the Authority, which shall not be unreasonably withheld. There shall be no departure from the performance requirements during the guarantee period.

S1.6.2 Recycled, secondary or virgin materials, or any combination thereof, are permitted by this Specification, provided they meet the performance requirements and any compositional requirements detailed in this Specification for the relevant material layer.

S1.6.3 Stabilised materials shall be permitted for use as surround to apparatus, and at backfill and sub-base layers, provided they meet the relevant performance requirements of this Specification.

S1.6.4 Alternative Reinstatement Materials are described in Appendix A9.

S1.7 Immediate Works

S1.7.1 There are circumstances when it is necessary to immediately reinstate an excavation, regardless of material availability etc., purely to enable traffic or pedestrian movement to occur on a traffic sensitive route. In such circumstances, reinstatements may be completed using excavated or other materials, properly compacted in 100 mm layers, with a minimum surfacing thickness of 40 mm of bituminous material.

S1.7.2 All materials so placed which do not comply with the requirements of this Specification shall be re-excavated and reinstated, to the appropriate interim or permanent standard as specified, as soon as practicable, but within 10 working days, or as agreed with the Authority following the completion of the immediate works.

S1.8 Apparatus within Road Structures

S1.8.1 Undertakers' apparatus greater than 20 mm external diameter will not normally be permitted within road structures.

S1.8.2 Apparatus of 20 mm external diameter or less shall not be permitted above or within 20 mm of the following levels within a road structure, see Figure S1.1:

1) The base (roadbase)/binder course interface in a flexible road.
2) The underside of the concrete road slab in a rigid road.
3) The underside of the modules in a modular road.

Figure S1.1 - Apparatus within the Road Structure

S1.8.3 Where other existing apparatus or surrounds occur within the road structure, the method of reinstatement shall be determined by agreement.

S1.9 Geosynthetic Materials

S1.9.1 Where the Authority knows of the existence of geosynthetic materials it should inform the Undertaker, prior to the commencement of works, so that an appropriate reinstatement method can be agreed.

S1.9.2 If the Undertaker is not informed of the existence of geosynthetic materials prior to the commencement of his works, but notices them during the works, he should inform the Authority immediately so that an appropriate reinstatement method can be mutually agreed. In these circumstances the Undertaker shall not be liable for the repair of any damaged geosynthetic materials caused by him not knowing of their existence.

S1.10 Trees

When working near trees the National Joint Utilities Group publication No 10 "Guidelines for the Planning, Installation and Maintenance of Undertaker Services in Proximity to Trees" (NJUG 10) should be followed. The publication gives comprehensive advice and should be read in its entirety. However, the following is a brief summary of its recommendations:

S1.10.1 Precautionary Area

The Precautionary Area is determined by measuring the girth of the trunk at chest height, multiplying this by 4 and using the resultant figure as the radius of a circle from the centre of the tree. The area inside the circle is the Precautionary Area in which precautions are essential.

S1.10.2 Precautions during Excavation

1) Don't excavate with machinery. Use trenchless techniques where possible, otherwise dig only by hand.

2) When hand digging, carefully work around roots, retaining as many as possible.

3) Don't cut roots over 25mm in diameter, unless the council's specialist agrees beforehand.

4) Prune roots which have to be removed using a sharp tool (e.g.; secateurs or handsaw). Make a clean cut and leave as small a wound as possible.

S1.10.3 Precautions during Reinstatement

1) The backfill should, where possible, include the placement of an inert granular material mixed with topsoil or sharp sand (not builders sand) around the retained roots. This should allow the soil to be compacted for resurfacing without damage to the roots and should secure a local aerated zone enabling the root to survive in the longer term.

2) Backfilling outside the road limits should be carried out using the excavated soil. This should not be compacted but lightly "tamped" and usually left slightly proud of the surrounding surface to allow natural settlement. Other materials should not be incorporated into the backfill.

3) Repeated movement of heavy mechanical plant (excavators etc.) should avoid the Precautionary Area, except on existing hard surfaces, in order to prevent unnecessary compaction of the soil. This is particularly important on soils with a high proportion of clay. Spoil or building material must not be stored in the Precautionary Area.

4) Care should be taken to avoid damage to the trunk and branches from machinery. A tree must not be used as an end stop for leaning paving slabs against after lifting, nor for security chaining of machinery.

S1.11 Conciliation and Arbitration

S1.11.1 This Specification is intended to provide sufficiently detailed guidance to enable agreement on its operation and implementation to be reached at local level. Authorities and Undertakers should always use their best endeavours to achieve a solution to disputes without having to refer them to conciliation. This might be achieved by referring the issue to management for settlement.

S1.11.2 If, however, agreement cannot be reached, the provisions set out in the Code of Practice for the Co-ordination of Street Works and Works for Road Purposes and Related Matters should be followed.

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