The objective of the Air Quality section of West Yorkshire’s Local Transport Plan 2006-11 is to limit transport emissions of air pollutants, greenhouse gases and noise, along with mitigating and adapting to the effects of climate change.
Factors that affect Air Quality
Weather conditions: Poor dispersion of air pollutants, caused by temperature inversions or low wind speeds can cause pollutants to become trapped in lower atmosphere resulting in poor air quality. Much better mixing and dilution of the pollutants occur with high wind speeds.
Traffic Flow Characteristics: When traffic flows become congested with frequent stop/start movements, vehicle emissions can be greatly increased and can lead to local air quality problems.
Traffic Composition: Emission factors for vehicles will depend on vehicle class and engine type (HGV, van or car), fuel type and Euro standard (permitted emission rates for vehicle type and age).
Background Concentrations of Air Pollutants: Urban areas will contain higher levels of background pollutants, due to increased traffic densities, congestion and associated vehicle emissions.
Rural and Urban Topography: Valley bottoms and contained street canyons can affect the dispersion of emissions, sometimes leading to elevated concentrations of pollutants. However, on windy days the orientation of valleys and street canyons can induce funnelling, leading to greater dispersion of pollutants.
Heat Wave Conditions/Climate Change: During heat wave conditions, photo-chemical reactions can modify road traffic emissions and produce acidic particulate matter and low level ozone, in areas downwind of conurbations. The frequency of heat wave conditions is likely to increase with climate change.
Legislation
The National Air Quality Strategy (NAQS) 2007 is the UK's response to enact the EU Air Quality Directives that place responsibilities on all Member States. The Strategy describes health based standards and objectives for 10 different air pollutants.
Visit the Department for Environment, Food and Rural Affairs (DEFRA) website for more information about NAQS and EU Air Quality Directives
Urban Air Quality Monitoring
A comprehensive audit of air quality has been instigated by the requirements of the NAQS. Each Local Authority within West Yorkshire has performed a combination of air quality monitoring and modelling, to enable comparison against relevant air quality standards.
Follow links below to view air quality monitoring graphs:
Monitored Nitrogen Dioxide Levels in Urban Areas (17kb pdf)
Monitored PM10 Levels in Urban Areas (16kb pdf)
Visit Local Authority Air Quality web pages for air quality monitoring data and explanations of the pollutants of concern:
Visit Leeds Council Air Quality web pages
Visit Kirklees Council Air Quality web pages
Visit Bradford Council Air Quality web pages
Visit Wakefield Council Air Quality web pages
Visit Calderdale Council Air Quality web pages
All West Yorkshire Local Authorities used a combination of real-time air quality monitoring equipment and diffusion tubes to monitor air quality at specific sites across their Districts. In order to audit air quality across whole of West Yorkshire and for future years, air quality dispersion models were used by each Local Authority.
For full details of each Local Authorities air quality monitoring regime follow the link below:
West Yorkshire LTP2 2008 Progress Report Section 2: Air Quality Update (Draft) (53kb pdf)
Air quality dispersion models require details of pollutant emission sources, which form the emission database. This database includes detailed information regarding traffic flow characteristics and from industrial emission sources. This information was used to help predict air quality across West Yorkshire.
For maps of pollutant concentrations for PM10 (Particulate matter), NOx (Oxides of nitrogen) and NO2 (Nitrogen dioxide) follow the links below:
For map depicting PM10 levels (4.5mb pdf)
For map depicting NOx levels (4mb pdf)
For map depicting NO2 levels (4.5mb pdf)
For further information on predicted background pollutant concentrations
Air Quality in West Yorkshire
Under the NAQS Review & Assessment process, all Local Authorities have identified air quality concerns specific to their district. In cases where relevant air quality standards & objectives are at risk of exceedance, Air Quality Management Areas (AQMA’s) have been declared. In other cases, Areas of Concern (AoC) have been established where the air quality audit process has identified potential problems, but need further evidence to quantify whether an AQMA should be declared. So far, all AQMA’s have been associated with high background levels of nitrogen dioxide from road transport.
Map of AQMA's and AoC can be found in the link below:
West Yorkshire LTP2 2008 Progress Report Section 1: Air Quality Update (Draft) (212kb pdf)
Air Quality Partnerships
Partnership Working
The West Yorkshire districts have worked in partnership with the following regional and national working groups:
- The Yorkshire and Humber Pollution Advisory Council (YAHPAC) – consists of environmental health professionals with a remit of leading on air quality and disseminating good practice.
- Environmental Protection (UK) - a charitable organisation that has played a leading role in environmental protection in the UK, since 1898
- Regional EMAQ events organised by AEA Technology – helps to share information relating to air quality modelling and assessment.
- The Low Emission Strategy Forum (LESF) - chaired by Sheffield City Council to consider low emission strategies for tackling transport related problems the group includes representatives from DEFRA.
- The Low Emission Strategies Development Project - Peer Group Project (Just started) – involves 4 Beacon Local Authorities and 10 other Local Authorities, including Leeds, who will work collaboratively to develop and deploy low emission strategies within their areas.
The West Yorkshire Transport Emissions Group (WYTEG)
The West Yorkshire Transport Emissions Group (WYTEG) chaired by Leeds, was originally set up to pool transport related environmental advice whilst conducting the Strategic Environmental Assessment for LTP2. The group contains expertise from environmental health, sustainability and transport planning, which have specialist knowledge in transport related air quality, climate change mitigation and adaptation and environmental noise. Members from all 5 West Yorkshire districts, the Highway Agency and the Institute of Transport Studies (Leeds University) normally attend the bi-monthly meetings.
Delivering Air Quality
The LTP 2 provides a mix of transport initiatives aimed at reduced reducing local and citywide vehicle emissions, thereby helping to improve air quality across all West Yorkshire Districts. These transport initiatives can be split into 3 main themes, including:
- Traffic demand management techniques
(eg. Promote public transport, priority measures and integrated transport)
- Encouraging more sustainable travel
(eg. Travelwise, travel plans, strategic environmental assessment)
- Actions to reduce vehicle emissions
(Traffic management schemes, use of cleaner fuels & vehicle technologies)
Further information on the West Yorkshire LTP2 Environmental Report / Strategic Environmental Assessment and LTP2 transport initiatives can be seen in the links below:
View the Local Transport Plan 2006-11 Transport Initiatives Flowchart (18kb pdf)
Links to the West Yorkshire LTP2 Environmental Report and Strategic Environmental Relate can be found below:
Read a summary of Local Transport Plan 2006-11 Delivering Air Quality (1mb pdf)
Local Air Quality Management (LAQM)
For information on Local Air Quality Management (LAQM) follow the links below:
LAQM Policy Guidance (England Only)
LAQM Technical Guidance (all of the UK)
LAQM Technical Guidance Support Tools
