Roads Development Technical Guidance
Argyll and Bute Council · 20 June 2024
Back to Environment, Development and Infrastructure Committee — 20 June 2024 and its agenda
Text extracted from the council's PDF. Layout and reading order may differ from the original.
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ARGYLL AND BUTE COUNCIL ENVIRONMENT, DEVELOPMENT AND INFRASTRUCTURE COMMITTEE ROADS AND INFRASTRUCTURE SERVICES 20 JUNE 2024 ROADS DEVELOPMENT TECHNICAL GUIDANCE 1.0 EXECUTIVE SUMMARY 1.1 The Roads Development Framework Technical Guidance provides a single document for new and existing roads aimed at the technical professions, including roads engineers, planners developers and contractors. 1.2 The document provides information on acceptable standards for both new and existing private roads and offers departures from previous standards. 1.3 The Technical Guidance sets out where discretion can be applied, noting that in the majority of cases this must be based on robust data (for example, forecast traffic flows). Offices can also consider local context when departing from standard. 1.4 Overall, the principles set out within the Technical Guidance aim to provide clear guidance to all those working within the profession in Argyll and Bute and seeks to deliver an appropriate balance between the needs of roads, planning, housing and the needs of the travelling public. 2.0 RECOMMENDATIONS 2.1 It is recommended that Members of the Environment, Development and Infrastructure Committee agree to adopt the Roads Development Technical Guidance. 3.0 DETAIL 3.1 The Argyll and Bute Council area is diverse in nature and character; both in population demographics and geometry, as well as features of the road network. It is challenging to find or agree a “one-size-fits-all” framework but it is important and fair that any development framework seeks to provide a broad consistency across the area.
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3.2 The draft Roads Development Technical Guidance, attached under Appendix 1, aims to meet National Policy but tempered to meet the local considerations as a broadly, rural authority. There are occasions where the local context does not provide a practicable adoption of national standards even though the Council may be supportive of its aims. An example of this may be the aspiration to achieve modal shift from private car journeys to walking, wheeling or public transport; however, while this may be achievable to some degree within the larger, more urban settlements, it is the reality that for the vast majority of our geographical area the desired modal shift is not likely to be achieved in the short to medium term. 3.3 The audience of the Technical Guidance is targeted towards ‘technical professionals’ working within the development field, although it is intended that the document will be available to all via the Council’s website. The document does, therefore, use technical standards and language and it may be useful to set out, here, the aim and purpose of the Technical Guidance. 3.4 Firstly, the following definitions may be of use Footway – the right of way is by foot only and it is associated with a carriageway (i.e. it abuts the carriageway). i. Footpath – the right of way is by foot only but is not associated with a carriageway, sometimes may be separated from the carriageway by a verge. ii. Cycle track – the right of way is by pedal cycle only or by pedal cycle and by foot. If contiguous (attached) with a carriageway it may be known as a cycleway, if not, it may also be known as a cycle path. iii. Verge – an area of land abutting the carriageway, normally grassed but may on occasion include planting and flower beds or other landscaped areas. iv. Carriageway – the right of ways above included but also includes a right of way by vehicle. v. Road Corridor – generally, the road corridor includes any carriageway, footway, verge etc. and may also include retaining walls, embankments and so on. 3.5 For new roads and developments, the Technical Guidance should be read alongside the National Roads Development Guide (NRDG). The NRDG is, effectively, the successor document to Strathclyde Regional Council’s Roads Development Guide (“orange book”). The Technical Guidance makes amendments and additions to the NRDG, considering local factors. In addition to this, the Technical Guidance also provides standards for: • Small housing developments (for 1 to 5 dwellings) • Small housing developments (for 6 to 10 dwellings) • Variation of road standards for specific islands • Adoption process for private roads (other than by Roads Construction Consent) • Guidance for developments on existing private road networks
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3.6 In broad terms, the Technical Guidance sets out the principles and standards which will ensure that new and existing roads are safe and convenient to all road users. For prospective adopted roads, the Technical Guidance will ensure that: i. Road layouts are designed to ensure their integration with the local environment, including road design, landscaping and parking. As far as practicable, parking will be provided off-street. ii. Road layout is designed to ensure it meets the need of all users, including the most vulnerable (children, pedestrians, cyclists, & those with mobility issues). iii. The road will be designed to meet the needs of forecast traffic volume and in such a way as to manage speed of vehicular traffic to ensure reduction in incidents and their severity. This will normally be achieved by road geometry (radii etc.) but may also require the installation of physical traffic calming (e.g. chicanes, road humps). 3.7 Alongside NRDG and the Technical Guidance, developers may also need to refer to Designing Streets and the Design Manual for Roads and Bridges (DMRB), these are the National Documents. 3.8 The Technical Guidance has been checked against the Argyll and Bute Council Local Development Plan 2 and is compliant with its outcomes. The Framework will provide planners and developers with a guide on what is likely to be conditioned and the reason why. It is expected that this will enable a smoother course for developers, planners and roads engineers and should improve the work flow when considering planning applications which include road implications, as the rationale for roads conditions etc are clearly explained within the document. 3.9 The following paragraphs set out what each section of the Technical Guidance covers, broadly, and highlights the main amendments to existing guidance or process documents. Local Variations to the NRDG 3.10 The full list of variations is contained in Appendix 1 “Argyll & Bute Council variations to National Roads Development Guide”. Section 2 of the Technical Guidance details the amendments and additions of the NRDG. The key changes are detailed in the subsequent paragraphs. 3.11 A section on “Parking Considerations” has been included within the Technical Guidance. This section outlines the added difficulty and impact of parking on rural or semi-rural roads. The section also highlights minimum bay sizes, the potential for inclusion of cycle parking and potential reductions within town centres with good public transport provision. Table A8 in the document, Car Parking Standards provides the minimum parking standards to be applied.
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3.12 The Technical Guidance also sets out the arrangements when contact should be made and the contact email for cases where Technical Approval is required, Structure approval or where work is required to be carried out on or near the Argyll and Bute Council structural assets (bridges, retaining walls and so on). 3.13 The Technical Guidance includes a section on Sustainable Urban Drainage Systems (SUDS), referring to the Council’s flood management guidance and where the Council will adopt the SUDS drainage into its asset. As a general rule, the Council will only adopt the SUDS drainage when it only contains road surface drainage, and it is located within the road corridor or where servitude rights have been granted for areas outwith the road corridor. There may be other circumstances relating to shared systems where the Council may wish to enter into an agreement with Scottish Water, this would be dependent on local circumstances and would be treated on an individual basis. 3.14 The document also sets out notification processes and related charges for the inspection of new developments. This sets out the minimum notification periods to allow the authority to arrange for quality inspections to be carried out prior at each stage of construction (for example, impaction of the roads sub-base layer prior to the bituminous layer being installed to ensure it has been compacted to the relevant specification). 3.15 The Technical Guidance includes two tables setting out the required visibility sightlines: one for lightly trafficked roads (Table A1), one for strategic and heavily trafficked routes (Table A2). The strategic routes are set out within Appendix 4 of the Technical Guidance, but routes are considered to be carrying heavy traffic if it has a traffic volume of 3,000 Vehicles Per Day (VPD). 3.16 Tables A3 and A4 of the Technical Guidance and the associated text set out the design parameters for urban road link geometry (A3) and rural road link geometry (A4). The tables set out when the Design Manual for Roads and Bridges should be used and where it is appropriate to use the local deviations. Both tables set out the maximum and minimum gradients permitted for road type and design speed. • For urban design, road type includes: o Strategic Route o Main Distributor o Local Distributor o Industrial Access Road o Main Residential Steet o Minor residential street, home-zone, Cul-de-sac • For the rural design, the road type: o A-Class o B-Class o C-Class o Unclassified o Single track access roads
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3.17 This section also sets out an additional restriction for the siting of private accesses in a rural environment, namely that they should not be constructed within 90 metres of a road junction or within 25 metres of an existing private access. 3.18 In most cases, the maximum permitted gradient will be 6%, however the document does allow a local departure from standard to be requested, which must be approved in writing by the Roads Authority. However, in no circumstances will a gradient exceeding 10% be permitted. Note, the 6% maximum gradient will remain as an absolute maximum where the route is a service bus route. 3.19 The Technical Guidance contains a section of industrial estate roads. This is the first Council document to detail the requirements for industrial estate roads. The design detail sets out a minimum carriageway width of 7.3 metres but notes that this may be reduced to 6 metres where commercial vehicle activity is limited. An example of the latter width may be a small unit development with one-way working. Where the narrower width is agreed, the development must be designed in such a manner as to restrict future growth of the site which would result in the road no longer being fit for purpose. 3.20 The industrial estate road section also sets out parking standards for staff and customers (including provision of cycle parking and disabled parking), turning- head detail, gradients, junction spacing, and visibility splays appropriate for larger vehicles. Table A5 sets out the industrial roads link geometry in detail. 3.21 A section was added within the Technical Guidance setting acceptable Housing Court developments (The NRDG is silent on this). Housing courts are permissible up to a maximum of 20 units and must be designed in such a manner with provides adequate servicing arrangements to be made. In addition to this, refuse collection must be provided as communal or centralised waste collection points to minimise disruption to, or create an unsafe practice in regard to the Council waste collection service. The inclusion of housing courts provides another option for developers to provide a reasonable number of units without needing to provide extensive new roads, potentially at high cost. Development Contributions 3.22 Section 3 of the Technical Guidance sets out when and under what powers the Roads Authority can seek contributions from developers. This may include contributions or, indeed, full payment of such items as the provision of new roads to access locked sites, improvements to existing local infrastructure, or commuted sums to pay for future maintenance of block paving or SUDS, for example. This is all under existing legislation, however, it sets out a framework for Officers to use but also makes it clear to Developers and others that this may be a requirement for developments in the future. Finally, if the contributions are not being lodged with the Council (or by some other agreeable process) then the contributions should be captured under Section 75 of town and country planning legislation, agreements as these are heritable with planning permissions.
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Small Housing Developments – 1 to 5 units 3.23 Section 5 of the Technical Guidance captures a previously drafted guidance document but formalises it and brings the sightlines etc. in line with the main body of the Technical Guidance . Most developers within Argyll and Bute will be aware of the previous guidance document, however, it does add detail around commensurate improvements and clarifies that integral garages will not be counted towards the overall parking provision (as they are easily converted to residential space post-construction). Small Housing Developments – 6 to 10 units 3.24 In general, it is desirable for a road serving a development of 6 units or above to be adopted to ensure the rights of the travelling public are protected, so that roads are maintained to a suitable standard and to ensure road safety for all users. 3.25 Notwithstanding the above point, Section 6 details circumstances where it may be appropriate to provide a development up to 10 units but in which the road would not be adopted. This section sets out the standards applicable in this case and outlines the process. This option may be particularly useful to very rural areas but more likely to island communities where the provision of a new public road to adoptable standard may not be achievable or feasible. Where this is deemed acceptable, adequate arrangement must be put in place to ensure the road is maintained in perpetuity (for example, burdens included within the title deeds). Variation of Road Standards for Specific Islands 3.26 As outlined in paragraph 4.24, it is preferred that new roads are adopted, however, Section 6 of the Technical Guidance specifically recognises the difficulties in delivering new roads on certain islands (namely, the islands of Coll, Colonsay, Tiree and Jura). This is particularly relevant in regard to the ability to access hot bituminous material from mainland quarries. 3.27 Section 6, therefore, sets out circumstances where this exemption can be considered and goes on to detail what standard will be acceptable (e.g., the use of concrete or unbound material instead of bituminous). Any road constructed to the standards set out in Section 6 will not be adopted onto the Public List of Roads and will remain private in perpetuity. Adoption of Private Roads 3.28 Section 7 provides an overview of the adoption process for existing private roads. Broadly, it provides detail on the legal background for adoption and what an applicant must include in its submission. This includes evidence that a majority of frontagers support the proposed section of road for adoption, a plan of the existing road layout and the proposed improvements to bring the road to an adoptable standard. With this information, the Roads Authority will
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provide a cost estimate for the works and propose to the frontagers an apportionment of the same. 3.29 Note, there is an existing road adoption policy which can be viewed here Policy for Council contribution towards bringing private roads up to adoptable standards. This policy shall be applied when considering any private road for adoption. Development on existing private road networks 3.30 Section 8 of the Technical Guidance provides a set of principles, intended primarily for roads officers but will be a useful guide for developers and planners alike, for the consideration of proposed developments from existing private roads or tracks. This isn’t intended for recently constructed private roads but for those of an historical nature, for example, an old estate road. 3.31 While the Roads Authorities principal concern will be with the private roads interface with the public road network, any proposed development will be reviewed similarly to any new road. Officers will review existing internal road layouts, widths, provision of passing places for single track roads, appropriate access for emergency services = and ensure the route provides sufficient road safety. 3.32 At the interface with the public road, any proposed development will need to provide (not exhaustive): i. Junctions must be safe, have sufficient sightlines, service bay, be widened out to 5.5 metres for the first 10 metres and be surfaced with bituminous material. ii. In most cases, the development will be required to provide bin store(s) for collection alongside the public road. iii. Notes, SUDS may be required. iv. Provision of turning heads within the internal road network capable of providing safe manoeuvres for service vehicles. Summary 3.33 The Technical Guidance provides a single document for new and existing roads aimed at the technical professions, including roads engineers, planners and developers. 3.34 The document provides information on acceptable standards for both new and existing private roads and offers departures from previous standards (particularly in terms of the number of units which can be served by a non- adopted road and a formal relaxation of material choices on remote islands).
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3.35 The Technical Guidance sets out where discretion can be applied, noting that in the majority of cases this must be based on robust data (for example, forecast traffic flows). Offices can also consider Argyll and Bute’s local context when departing from standard. 3.36 Overall, the principles set out within the Technical Guidance aim to provide clear guidance to all those working within the profession in Argyll and Bute and seeks to deliver an appropriate balance between the needs of roads, planning, housing and the needs to of the travelling public. 4.0 CONCLUSION 4.1 This report summarises the content of the Roads Development Technical Guidance and seeks that the Technical Guidance be adopted and used for future developments which involve either the existing road network or proposed new roads. 5.0 IMPLICATIONS 5.1 Policy – New Technical Guidance for roads development (existing and new). 5.2 Financial – None but may secure contributions from developers for infrastructure improvements arising due to future developments. 5.3 Legal – New Technical Guidance has been reviewed to ensure it meshes with the LDP2. 5.4 HR – None. 5.5 Fairer Scotland Duty: 5.5.1 Equalities - protected characteristics – no concerns. Seeks to improve better access arrangements for those with mobility issues. 5.5.2 Socio-economic Duty – recognises the need for housing and has provided reduced road standards in specific situations. 5.5.3 Islands – remote islands may seek reduced road standard (use of non- bituminous materials). 5.6 Climate Change – construction of new roads has a carbon output, however, the Technical Guidance encourages modal shift, as far as practicable in a rural authority, (through active travel, green plans, cycling and walking etc.) which may have beneficial carbon reduction. 5.7 Risk – provides clarity for those working within the associated technical professions. Technical Guidance should reduce risk overall. 5.8 Customer Service – N/a. 5.9 The Rights of the Child (UNCRC) – None known.
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Executive Director with responsibility for Roads and Infrastructure Services: Kirsty Flanagan Policy Lead for Roads, Transport and Amenity Services: Councillor John Armour May 2024 For further information contact: Jim Smith, Head of Road and Infrastructure Services jim.smith@argyll-bute.gov.uk Stuart Watson, Assistant Network & Standards Manager stuart.watson@argyll-bute.gov.uk APPENDICES Appendix 1 – Road Development Technical Guidance