Bath & North East Somerset Council - Highway Structural Maintenance Programme

Highway Structural Maintenance Programme

The annual highways structural maintenance programme is funded from capital expenditure sourced through;

Local Transport Plan Maintenance Block Funding from Central Government
Section 31 Grant Funding
Council Capital Funding

This annual programme of works is segregated into the improvement of a variety of highway assets as follows:

All the works included in the carriageway and footway/footpath programmes are subject to rigorous prioritisation processes with the intention of ensuring that the worst assets are attended to first. Significant work is done in terms of machine and visual surveys, analysis of revenue expenditure and safety inspection records all assessed against network hierarchy in determining priority and treatment to be applied.

Our Street Work team work both internally with other departments and externally with public utility compaines to co-ordinate works across our highway network and those of neighbouring authorities.

Carriageway Improvement Works

Surfacing and Reconstruction Works

These works traditionally involve overlaying or inlaying large areas of carriageway and where necessary carrying out deeper reconstruction on isolated areas where significant structural failure is evident. Coring investigation work is undertaken beforehand to fully assess the work required.

The overlaying of an existing carriageway will involve treating the surface with a tack coat on to which a new surface course is applied. Inlaying is more intrusive as it involves planing and milling of the existing surface followed by the application of tack coat and new surface course. With both processes there is the need to adjust the height and level of all ironwork along the affected length.

Typical surface course materials are Asphalt Concrete (bitumen macadam), Hot Rolled Asphalt or another selected proprietary product selected to meet local site conditions.

Due to the health and safety of both highway users and operative carrying out the works this type of work in most cases necessitates a road closure for the duration. To minimise disruption to highway users these works can on accession be carried out overnight and on weekends. School holidays and local events are considered in the planning and programming of these projects.

Surface Dressing

Surface dressing is a simple and highly cost-effective method of repairing the road surface, which can prevent much more expensive work being needed later. It allows us to maintain a high quality road network on a finite budget.

The process involves spraying the road surface with a coating of hot liquid bitumen, known as a binder. The coating is then covered with clean crushed stone chippings, which are rolled into the bitumen to form a water-resistant, protective layer, which improves skid resistance.

This type of work can only be done in the spring and summer months, when the weather is warm and dry, as the bitumen will not stick to the road in cold or wet conditions. This is a mobile operation and is an efficient process that allows us to reduce the time on site thus causing minimum disruption to local highway users. These works are normally only carried out on the rural roads of our Network as using hot applied binder is not suitable within urban areas.

Micro Asphalt

Micro Asphalt Surfacing consists of bitumen emulsion and aggregate slurry which is laid cold by a specialised machine. The surfacing seals the top surface and improves skid resistance not dissimilar to Surface Dressing.

This type of surfacing is widely used in the urban areas of our Network. The finished surface has a low noise characteristics and good riding qualities; as this is a mobile operation it is an efficient process that allows us to reduce the time on site thus causing minimum disruption to local highway users.

Footway/Footpath Improvement Works

Paving

These works essentially involve the improvement of natural stone or concrete slab paved areas generally concentrated in the City or Town Centres and other shopping areas.

Asphalt Concrete

These works are carried out by excavation and relaying of Asphalt Conrete (bitumen macadam) footway alongside carriageways or on footpaths not associated to a road.

Slurry Sealing

This process is a simple and cost affective method of sealing and tidying up significant areas of footpaths and footways. It is best carried out in the spring and summer months to avoid laying on cold wet surfaces.

Highway Structures Improvement Works

This programme of works is necessary to improve and maintain the Authorities Highway Structures Stock. These are predominantly highway bridges, retaining walls/other retaining structures and culverts under the highway.

Street Lighting Improvement Works

This programme of works involves improvements to Street Lighting and highway electrical assets.

Column Replacement Programme

As part of the Street Lighting Maintenance Programme, every column is given a visual inspection at least once in three years and allocated a Structural Condition Level:

1 GOOD - indicates that there is a possible need for replacement between 15 and 25 years

2 ADEQUATE - indicates a possible need for replacement between 5 and15 years

3 POOR - indicates the possible need for replacement within the next 5 years.

We know that we have a number of columns at any given time which will require replacing within 5 years. However there are also other columns of certain design or age that are very close to life expiry and these are also being changed as soon as is practicable.

Owing to the fact that we are dealing with the older columns it follows that the roads which they illuminate now have lighting levels below the current standards for the present traffic carried. Also the lanterns are usually of the ‘low pressure sodium’ type with poor optical control and a yellow-coloured light. This means that the light is produced in virtually all directions but does not render colours visible.

The opportunity is therefore taken to redesign each road as a new scheme to modern standards which does mean that the new column positions will not necessarily coincide with those existing. A GREATER SENSE OF WELL-BEINGModern lanterns using ‘high pressure sodium’ lamps are utilised, having very good optical control. This enables the light output to be focussed down onto the road and footway with no waste light upwards.

The brackets can be dispensed with, also reducing the visible daytime clutter. The light, being whiter, does enable facial features and colours to be recognised. These latter points contribute to a greater sense of well-being, particularly encouraging people to walk out at night. This in turn can enhance the sense of community.