Appendix C - Ancillary Assets

Overview

The trunk road network includes not just carriageways and structures, but also footways, lighting, traffic signs, drainage networks and much else besides. Ancillary assets cover all trunk road asset types with the exception of the carriageway, road structures and Intelligent Transport Systems (ITS). This section of the RAMP describes asset-specific information that is used to develop the life cycle plan for trunk road ancillary assets, as detailed in ‘Making Asset Life Cycle Decisions’.

Asset Knowledge

The Ancillary Assets

The section below details the trunk road ancillary assets, their definitions and quantities. The inventory records held for ancillary assets comply with the requirements set down in Transport Scotland’s Trunk Road Inventory Manual and are held within our Asset Management Performance System (AMPS).

Fences & Barriers

Fences and Barriers

A barrier which runs alongside the carriageway for screening noise, glare or to prevent access. We have 748 km of fences and barriers across our network. This asset has a lifespan of 20 years.

Traffic Control Barriers

A moveable barrier or gate which can control the flow of traffic or close sections of the road. We have 43 traffic control barriers across our network. This asset has a lifespan of 15 years.

Pedestrian Guardrail

A protective fence usually on the edge of a footway intended to prevent pedestrians from stepping on to the carriageway. We have 42 km of pedestrian guardrail across our network. This asset has a lifespan of 20 years.

Drainage

Balancing Pond

A catchment area to collect surface run-off following heavy rain and control its discharge into a drainage system to prevent flooding. Some ponds hold water permanently; some are largely dry. We have 67,307 m² of balancing ponds across our network. This asset has a lifespan of 20 years.

Catchpit

A chamber with a sump or pit to collect silt or solid material and prevent it from blocking the drains. It may have an access cover or metal grating cover, similar, but larger in size than a gully. We have 9,984 catchpits across our network. This asset has a lifespan of 30 years.

Channel

A narrow longitudinal strip, generally near the edge of the carriageway, constructed to carry and lead away surface water. We have 66 km of channels across our network. This asset has a lifespan of 30 years.

Combined Kerb Drainage

A kerbline that contains a drainage channel inside the block. We have 66 km of combined kerb drainage across our network. This asset has a lifespan of 30 years.

Counterfort Drain

A field drain filled with granular material, which may be laid over a porous or perforated pipe. We have 90,713 m² of counterfort drains across our network. This asset has a lifespan of 30 years.

Ditch

A trench adjacent to a carriageway for drainage, generally running parallel to the carriageway. We have 755 km of ditches across our network. This asset has a lifespan of 15 years.

Filter Drain

A drain surrounded by granular material which remains visible (such as gravel), within which may be laid a porous or perforated pipe. We have 1,614 km of filter drains across our network. This asset has a lifespan of 27.5 years.

Gully

A chamber at the side of the road to collect surface water and trap debris. We have 91,506 gullies across our network. This asset has a lifespan of 25 years.

Grip

A shallow trench across the verge of a road to lead surface water away from the carriageway. We have 33,846 grips across our network. This asset has a lifespan of 5 years.

Piped Grip

A chamber constructed to give access to a drain, sewer or other underground service. We have 15,466 piped grips across our network. This asset has a lifespan of 20 years.

Manhole

A chamber constructed to give access to a drain, sewer or other underground service. We have 32,600 manholes across our network. This asset has a lifespan of 30 years.

Small Culvert

An enclosed channel or large pipe for water to flow under or alongside the road. We have 135 km of small culverts across our network. This asset has a lifespan of 40 years.

Drainage Ancillary Item

Any other drainage asset such as soakaways, headwalls, spillways, sluices and pumps. We have 11,152 drainage ancillary items across our network. This asset has a lifespan of 20–30 years.

Geotechnical

Slopes

Slopes above or below the road; are one of the following:

• Earthwork – an artificial slope often described as an embankment or cutting;
• Land – a natural slope assessed by the Scottish Road Network Landslide Study as posing a risk;
• Rock – an artificial slope, normally a cutting, where the face is rock.

We have 187 km² of slopes across our network. This asset has a lifespan of 50 years.

Protection/Rigid Support

Covers a range of constructions including:

• Retaining walls <1.5m,
• Buttresses,
• Beams, columns, props,
• Dentition,
• Revetments,
• Sprayed concrete facings,
• Riprap and armourstone as toe ballast or erosion protection.

We have 17,704 m² of protection/rigid support structures across our network. This asset has a lifespan of 30 years.

Other Geotechnical Assets

Covers a range of geotechnical measures such as:

• Anchors/Bolts/Dowels,
• Barrier Fencing,
• Debris Traps,
• Granular Replacement,
• Reinforced Soil,
• Rock Netting,
• Soil Nailing

We have 1,464 m² of other geotechnical assets across our network. This asset has a lifespan of 20-50 years.

Lighting and Electricals

Lighting Point

A lighting installation usually consisting of a column, lantern housing and lamp. We have 22,598 lighting points across our network. This asset has a lifespan of 20 years.

Electrical component of Traffic Signs or Bollard

The electrical part of a lit sign or bollard. We have 3,549 electrical components for traffic signs or bollards across our network. This asset has a lifespan of 15 years

Electrical component of Cabinet/Pillar

The electronic, communications or similar equipment contained within a cabinet. We have 2,440 electrical components of cabinets/pillars across our network. This asset has a lifespan of 15 years.

Electrical Ducting and Cable

An underground ducting system to carry electrical cables to electrically powered apparatus. We have 31 km of electrical ducting and cable across our network. This asset has a lifespan of 20 years.

Navigation Aids and Lights

Electrically energised marine navigation radar beacons and lights for Sea and Aircraft. We have 63 navigation aids and lights across our network. This asset has a lifespan of 20 years.

Cable Chamber

A chamber associated with road lighting, traffic signals, detector loops and other apparatus. We have 2,351 cable chambers across our network. This asset has a lifespan of 30 years.

Miscellaneous

Equipment Storage Location

A location other than a depot where equipment and/or materials are stored. We have 17 equipment storage locations across our network. This asset has a lifespan of 15 years.

Salt Bin

A bin containing salt or grit for use during winter conditions. We have 13 salt bins across our network. This asset has a lifespan of 15 years.

Pedestrian & Cycle Facilities

Footway

A part of the road exclusively for the use of pedestrians or pedal cycles. We have 890 km of footways across our network. This asset has a lifespan of 20 years.

Cycle Facility

A part of the road specifically for the use of pedal cycles. We have 26 km of cycle facilities across our network. This asset has a lifespan of 20 years.

Road Markings, Studs & Kerbs

Road Markings

Markings on the carriageway, split into:

• Hatched,
• Longitudinal,

We have 11,803 km of road markings across our network. This asset has a lifespan of 3–5 years.

Road Studs

Studs placed on the carriageway to guide traffic. We have 8,677 km of road studs across our network. This asset has a lifespan of 5 years.

Kerbs

A border, usually upstanding at the edge of a carriageway or hard shoulder. We have 3,526 km of kerbs across our network. This asset has a lifespan of 30 years.

Technology Equipment

Cabinet/Pillar

A cabinet or pillar, usually containing electronic and/or communications, traffic signal equipment or similar equipment. We have 2,602 cabinets/pillars across our network. This asset has a lifespan of 15 years.

Detector Loop

A wire loop embedded in the road surface to detect the presence or speed of a vehicle. We have 2,322 detector loops across our network. This asset has a lifespan of 10 years.

Weather Station

A remote electronic monitoring device to detect road surface and atmospheric conditions to give early warning of ice and frost. We have 159 weather stations across our network. This asset has a lifespan of 12 years.

Traffic Signs & Signals

Bollard

A device placed on a refuge, traffic island or verge to warn drivers of obstructions or to prevent the passage of vehicles. We have 68,624 bollards across our network. This asset has a lifespan of 10 years.

Traffic Sign

Any object or device for conveying to traffic or any specified class of traffic; warnings, information, requirements, restrictions, or prohibitions of any description. We have 59,133 traffic signs across our network. This asset has a lifespan of 10 years.

Reference Marker Post

Physical markers, typically located on the hard shoulder or central reserve, showing the direction to the nearest emergency telephone every 100m on motorway sections. We have 4,340 reference marker posts across our network. This asset has a lifespan of 7 years.

Snow Pole

Poles mounted at the side of the road to aid snow clearing operations. We have 5,397 snow poles across our network. This asset has a lifespan of 10 years.

Traffic Signals

A system of coloured lights for stopping traffic and permitting them to move. Consists of:

• Signal Heads,
• Detectors,
• Pedestrian Push Button,

We have 2,075 traffic signal systems across our network. This asset has a lifespan of 20 years.

Vehicle Restraint Systems

Safety Fence

A continuous barrier erected alongside a carriageway or bridge. We have 1,945 km of safety fences across our network. This asset has a lifespan of 20 years.

Crash Cushion

A crash cushion absorbs energy at a controlled rate; found installed in front of a structure or mounted on the end of a safety fence/barrier. We have 217 crash cushions across our network. This asset has a lifespan of 30 years.

Arrester Bed

Area adjacent to the road filled with a material to decelerate and arrest errant vehicles. We have 313 m of arrester beds across our network. This asset has a lifespan of 20 years.

Landscaping

Bulb Area

An area of naturalised or planted bulbs. We have 129,056 m² of bulb areas across our network.

Grassed Area

A defined area of predominantly grass cover ranging from highly maintained road verges or feature areas to unimproved, low maintenance grasslands which are often more remote from the carriageway or covering embankments or cuttings. We have 29 km² of grassed areas across our network.

Hedge/Hedgerow

Linear planting, may include trees.

• Hedge - intended to be formally shaped and maintained.
• Hedgerow - not intended to be formally maintained.

We have 276 km of hedges and hedgerows across our network.

Scrub

An area of self-seeded vegetation, often comprising gorse, broom, birch, alder and/or bramble up to a height of approximately 3m. We have 6 km² of scrub areas across our network.

Shrub

An area of small to medium-sized woody plants that are generally smaller than trees. We have 215,965 m² of shrub areas across our network.

Tree

A perennial plant with a woody self-supported trunk and branches. We have 2,171 trees across our network.

Wetland

An area of permanent or semipermanent water from open water bodies to boggy ground. We have 45,105 m² of wetlands across our network.

Wildflower Area

An area of sown, naturalised or naturally occurring herbaceous and/or flowering ground cover species. We have 116,172 m² of wildflower areas across our network.

Wildlife Mitigation Area

Intended to mitigate the potential impact of the road or traffic on wildlife. We have 66,345 m² of wildlife mitigation areas across our network.

Woodland

Grouping of predominantly tree species. Can include a shrub and/or a ground cover layer. We have 16 km² of woodland across our network.

Invasive and Injurious Species

An area where there is evidence of Invasive or Injurious species. We have 1 km² of invasive and injurious species areas across our network.

Inspections and Surveys

In addition to the surveys described in ‘Asset Knowledge’, our Operating Companies are required to undertake the following inspections:

Specialist Road Markings Surveys

Includes retro-reflectivity testing to ensure that markings of the line can reflect light from the vehicle back to the driver during the hours of darkness and skid resistance testing to ensure that markings are providing a specified level of surface grip.

Specialist Road Stud Testing

Undertaken to ensure that road studs (often referred to as cats’ eyes), are reflecting light from vehicle headlights during the hours of darkness.

Specialist Drainage Inspections

Generally undertaken using specialist surveying techniques to investigate a potential problem identified through safety or detailed inspections, such as flooding or blockages.

Landscape Opportunities inspections

Undertaken by the Landscape Architect at intervals not exceeding 12 months in order to identify potential opportunities to improve the landscape associated with the trunk road network.

Specialist Woodland inspections

Inspections of woodland and trees are also required at set intervals.

Monitoring Performance

The performance of ancillary assets is monitored by undertaking regular inspections and surveys. The collection of condition data for ancillary assets will enable us to compare the performance of assets across the trunk road network and assess how they are performing over time.

This information is used to inform maintenance strategies and assess how these assets are performing over time, for any defined scenario.

Ancillary Asset Condition

Ancillary assets are categorised by the severity of their defects according to five levels of service or condition categories. These condition categories are ‘excellent’, ‘good’, ‘fair’, ‘poor’ and ‘very poor’. The condition categories developed for footway and cycle facilities and road markings are shown as examples in ‘Footway and Cycleway Condition Categories’ and ‘Gully Condition Categories’ below. Further detail on current ancillary asset condition can be found in ‘Ancillary Asset Condition’

Footway and Cycleway Condition Categories

Excellent

New or nearly new condition with no obvious visual defects. May have obvious signs of disturbance in the surrounding grassed areas indicating recent works.

Good

An even and comfortable surface, free from defects and with few visible signs of surface deterioration. Showing no signs of the original construction works and all surrounding grassed areas returned to vegetation.

Fair

Free from safety defects but poor visual aesthetics. Evidence of initial deterioration, minor cracking, crazing and fretting. Minor isolated spot defects. Poor quality reinstatements including minor differences in level with original surface. Minor settlement/unevenness or filler loss on block paved areas.

Poor

Extensive cracking, failed patching, potholes, standing water (>10mm deep), small areas of depression (>25mm) or slab trips (>20mm). Extensive missing filler and/or loose blocks. Extensive wearing of screed for cycle facilities.

Very Poor

Requires replacement/rehabilitation, life expired. Effects include extensive and severe surface failure, cracking, distortion or slab trips. Complete loss of screed for cycle facilities.

Gully Condition Categories

Excellent (E)

New or nearly new. May show obvious signs of new construction and differences in the condition and colour of the surrounding carriageway surface.

Good (G)

No visual defects with few visible signs of surface deterioration. Very minor signs of weathering.

Fair (F)

Minor rocking and projections. Level different with carriageway not exceeding 10mm. Relative movement under load not exceeding 10mm. Minor differential between component levels. Minor corrosion of ironwork. Minor deterioration of the surface around the cover.

Poor (P)

Projections greater than specified maximum (20mm). Level difference with carriageway exceeding 10mm. Rocking under load, worn covers, major differential in component levels. Moderate corrosion of ironwork. Longitudinal gaps greater than 20mm that may cause danger to cyclists or pedestrians.

Very Poor (VP)

Missing, cracked or broken covers. Rocking grating/cover causing intrusive noise in urban areas. Major corrosion of ironwork. Collapse of chamber, gully frame and/or major deterioration of the surface around the cover.

Customer Satisfaction

Transport Scotland conduct an annual customer survey of users of the trunk road network. Findings include customer satisfaction regarding visibility of road signage (62% either ‘very satisfied’ or ‘fairly satisfied’), provision of lighting along roads (60% either ‘very satisfied’ or ‘fairly satisfied’), provision of signs at decision-making points (60% either ‘very satisfied’ or ‘fairly satisfied’), visibility of road markings (51% either ‘very satisfied’ or ‘fairly satisfied’) and provision of laybys and parking facilities (49% either ‘very satisfied’ or ‘fairly satisfied’).

There are also specific questions covering satisfaction with the general condition of cycle lane surfaces (20%’ fairly satisfied’) and footway surfaces (18% either’ very satisfied’ or ‘fairly satisfied’), with more detail in Figure C-1 and C-2 below.

(Note: Where percentages do not sum to 100%, this may be due to computer rounding, the exclusion of ‘don’t know’ categories or multiple answers.)

Maintenance

Full details of the maintenance requirements for ancillary assets are provided in our Operating Company contracts, (details of which are provided in ‘Our Operating Companies’). Maintenance activities undertaken for ancillary assets typically include:

Cyclic Maintenance

Day-to-day servicing, rather than repair, of assets to keep them operating. Examples include weed control (on footways, cycle lanes, kerbs etc.), pressure jetting of combined kerb drainage, checking tensioning devices on relevant road restraint systems and litter picking.

Reactive Maintenance

Unplanned work normally identified through the inspections described in ‘Inspection and Surveys’ or reports from members of the public. The requirements for defect repairs for all categories of defects are described in the Trunk Road Inventory Manual (TRIM).

Programmed Maintenance

Moderate to major work which aims to improve the condition and functionality of the asset, planned one or more years in advance. For more information, see ‘Scheme / Programme development’.

Winter Service

Transport Scotland undertakes steps it considers reasonable to prevent snow and ice endangering the safe passage of customers utilising the trunk road network. This includes gritting of footways and cycleways.

Analysis

Historical Trends

Funding since 2021 is outlined in Figure C-4 below, along with illustration of the corresponding trend in condition in Figure C-5.

Current State of Our Assets

The condition of trunk road ancillary assets, aggregated under eight asset groups is presented in Figure C-6. Currently 98% of lighting assets, 95% of technology assets, 90% of footways, and 90% of road markings are in ‘excellent’, ‘good’, or ‘fair’ condition.

Investment Scenarios

Further detail to the investment scenarios outlined in 'Investing in Our Network’ is provided below, with a focus on ancillary assets. Figure C-7 visually compares the different investment options and is supported by additional commentary on the removal of backlog and maintenance of condition scenarios.

Budget Required to Remove Backlog

To remove the £256 million ancillary asset maintenance backlog within ten years, an average investment of £110 million per annum is required (excluding CPF). (See Figure 5-7 in the RAMP for more information on the backlog).

Budget Required to Maintain Current Condition

The investment required to maintain trunk road ancillary assets at current condition levels is £83 million per annum (excluding CPF).

Baseline Budget Required to Meet Core Commitments

The minimum funding necessary to ensure road safety for users, in line with statutory obligations and national standards.

Scheme / Programme Development

An annual process of developing works programmes is applied, with draft programmes developed for one and three years ahead. This allows for short and medium-term planning on a rolling basis.

The Operating Companies then meet with Transport Scotland to review the draft programmes and estimates, and indicative budgets are allocated. Detailed estimates can then be developed for each scheme within the one-year programmes and ultimately finances and works orders are agreed and issued before work commences.

The purpose of an ancillary asset scheme is to deliver appropriately designed planned maintenance to improve or renew the asset, based upon its current condition. The treatment undertaken should enable the asset to be reset to a condition that removes the need for further maintenance (besides routine maintenance) during the expected serviceable life of the asset.

Where appropriate, renewals of ancillary assets are undertaken as part of programmed carriageway or structure maintenance schemes as this will reduce disruption to the road user and provide good value for money.

Renewals

Programmed maintenance on ancillary assets is typically of a lesser nature than those undertaken on carriageways and structures, for example:

• Patching and maintenance of footways and cycle lanes
• Replacing roadside kerbs
• Road lighting and electrical work
• Repair and/or replacement of safety fences
• Repainting of road markings and replacement of road studs
• Repair and remedial works to earthworks, embankments and cuttings

Our Operating Companies are required to log all Category 2 defects found during Detailed Inspections in our Asset Management Performance System (AMPS). They are then required to produce short to medium-term work programmes by prioritising, preparing and submitting programmes and bids for the repair of these defects while at the same time taking account of service life and life cycle requirements. Where appropriate, renewals of ancillary assets are undertaken as part of programmed carriageway or structure maintenance schemes as this will reduce disruption to the road user and provide good value for money.