|Managing the effects of aggregates transport
Local planning authorities have an obligation to manage the transport of aggregates in a way that avoids additional congestion, protects road safety, and minimises environmental damage. This requires a package of measures, rather than a single initiative, and planners and operators will need to look at the whole picture rather than their own operational or regulatory area. Options for preventing and minimising the effects include:
- A Transport Assessment (TA) should be undertaken as part of an Environmental Impact Assessment for the project or as a stand-alone study included in the minerals planning application. A TA should include details of other developments in the area that might cause impacts, as well as baseline and predicted information on road capacity, condition, traffic and congestion.
Consideration of alternatives:
- Alternatives should be considered early and on a case-by-case basis, particularly as some authorities have presumptions against the use of significant lengths of local roads to gain access to major road networks. Where alternative facilities of suitable quality exist and are economically viable, it is important to also consider their negative effects before the optimum transport method is defined.
Routing and traffic management:
- If the TA shows that additional traffic is likely to overload the road network, then road improvements or even new roads to avoid sensitive or congested areas may be required before aggregate transport begins.
- The number, route, condition and timing of vehicle movements should be agreed with the operator. The effects of HGVs on sensitive areas residential areas may be addressed by requiring vehicles to avoid such routes altogether through legally binding or voluntary agreements between the site operator and the mineral planning authority.
- Because the size rather than weight of HGVs causes most damage to verges and passing difficulties and hazards to other road users, highway authorities can limit the size of vehicles permitted to use particular roads during, for example, peak morning and evening rush hours or the start and finish of the school day.
- Convoys of HGVs, especially when traveling through country lanes or residential areas, should be avoided by ensuring that departure times from the site are staggered.
Convoying of lorries increases disturbance in surrounding villages.
Design and construction of site access points:
- Site access points are a critical interface with the wider area and sensible precautions to protect public safety include traffic calming and traffic islands to reduce speeds and discourage overtaking around the entrance; the use of slip roads; and road signs to indicate the entrance and slow-moving vehicles.
Control of fugitive materials:
- To prevent carrying mud, dust or dirt onto the highway, the wheels, undersides and body of HGVs should be cleaned before joining the public highway. The access road should be paved and regularly cleaned to reduce the potential transfer of mud and dust to the public highway.
- Operators should sheet their vehicles, preferably using automatic sheeting systems, to prevent spillage and reduce the potential for the deposition of material on public highways.
Control of noise and vibration:
- Silencers should be well maintained and replaced if they begin to get noisy. Vehicles should ideally be fitted with disc brakes to minimise brake squeal. Noise can be further reduced by fitting rubber bushes between the trailer body and chassis, or clamping the body and chassis together.
Spray cleaning a vehicle before it leaves the site reduces the dust taken out onto the public highway.
- The noise from exhaust and breaking systems may also be significant for vehicles traveling at night and so voluntary speed restrictions can play an important role in the control of noise during these periods.
- The use of slip roads at site access points can minimise the need for rapid acceleration or breaking.
Control of air emissions:
- Low emission engines and regular maintenance and servicing can significantly reduce exhaust emission levels from road-transported aggregates and ensure vehicles meet appropriate standards.
Driving standards and codes of conduct:
- Operators may choose to limit speeds to below the statutory limit on certain routes where speed represents an actual or perceived risk to public health and safety.
- Drivers should take care to ensure their vehicles do not run over or damage verges, curbs and footpaths.
- Vehicles should be parked securely to ensure that they present no hazard or inconvenience to other road users or residents. Operators could provide suitable overnight parking away from sensitive neighbours.
- MPAs can encourage the use of a 'code of conduct' for drivers to help ensure that they follow the routing and timing agreed, observe speed limits, and show appropriate consideration for other road users.
Key facts and quotes
- Regular environmental audits and spot checks of the operator's and subcontractor's vehicles can be used to ensure compliance with conditions laid down by the MPA.
- Traffic noise surveys can determine if excessive noise is being generated by aggregates vehicles.
- Vehicles should be marked clearly with an identification number on the side and tailgate so that drivers contravening any legal or voluntary agreements can easily be identified by the operator or members of the public. A 'How Am I Driving?' or 'Well Driven?' scheme can also encourage good driving.
Transport by HGVs is likely to remain the main means of transporting aggregates in the foreseeable future.
HGVs used to transport aggregates can have significant negative effects on the health, environment, access and safety of those using, and living close to, roads on which they pass.
Managing transport effects requires a package of measures, rather than a single initiative.
References and sources of further information
- ENTEC UK Ltd. 1998. The environmental effects of traffic associated with mineral workings . Report for the Department for the Environment, Transport and the Regions.
- Goodquarry.com - Transport and traffic: Click here
- King, N. 2004. Traffic. Chapter 4 in Environmental Management , The Institute of Quarrying, edited by M S Watkins and M R Smith, ISBN 0-9538003-4-2.
- NECESI/The Environment Practice. 2004. Traffic. Chapter 4 (Section B-I) in Environmental management guidance manual for SME aggregates companies. March 2004. Available from NECESI, University of Durham, Unit 1R, Mountjoy Research Centre, Stockton Road, Durham DH1 3SW.