9.7 AQMA Mandatory Indicator and Monitoring Process

9.7.1 Monitoring Process for Lancashires AQMAs

In addition to LTP8, each Lancashire AQMA will be monitored individually and the results, combined with outcomes, will be included in Annual Progress Reports. This reporting will use traffic data with a base year of 2004/5 and a target year of 2010/11.

Diffusion tubes are the preferred method of obtaining accurate air quality data. A comparison of observed and modelled results shows that diffusion tubes provide a consistent approach for all Lancashire’s AQMAs, whilst calculated results do not provide a true representation of air quality. Local influences were deemed the source of the differences in concentration levels. Modelling, however, is required to determine the impact of measures from the ‘do nothing’ scenario.

Air quality is modelled using the DMRB Screening Method 1.02 and the results are used to determine the net differences between a ‘do nothing’ and a ‘do something’ scenario. The ‘do something’ includes the effects on air quality from identified packages of work which will form part of the Action Plan of an AQMA. This procedure has been undertaken for Lancaster. As other Action Plan measures are finalised and agreed through consultation, their impacts will be calculated and used to update Lancaster's mandatory indicator and trajectory. This process will be replicated for all AQMAs and included in Annual Progress Reports.

9.7.2 Observed Air Quality Data NOx

Air quality is continuously monitored using diffusion tubes and the results are published by Local Authorities. Diffusion tube locations are carefully chosen to represent an AQMA. Tubes are located either mid link or near the critical junction, dependent on the AQMA. They are generally attached to lampposts or buildings at a height of 2 metres. However, in isolated locations concentrations may be higher or lower than those observed. To take account of over and under-read diffusion tubes, all results are bias corrected to establish their annual mean.

The current trajectory is based on 2 years continuous monitored data. When the results for 2005 (bias corrected) are available, they will be used to update the ‘do nothing’ trajectory.

9.7.3 Traffic Flow

Traffic flow into each AQMA will be monitored between 07:00 and 10:00, as for indicator LTP6. The Average Annual Daily Flow on AQMA links will also be monitored .

Where an AQMA includes highway links that are monitored for indicator LTP6, or are a continuation of those links, it is expected that the LTP6 target will be exceeded. On these links the Council will aim to have no increase in traffic flows during the peak period with a slight reduction during the peak hour. On other links that form AQMAs it is expected that the LTP6 target will be achieved.

9.7.4 Air Quality and Traffic Flows in Lancashire

The following table is the summary of the air quality and traffic data within AQMAs. Where available, individual trajectories are shown. To indicate the overall level of success in improving air quality within Lancashire, combined air quality within Lancashire's AQMAs has been calculated, giving a Lancashire trajectory. A graphical representation of the Lancashire average exposure per resident to oxides of nitrogen is included in the AQMA section in the District chapters.

Table 9.7.4

Air Quality and Traffic Flows on Primary Links within AQMAs
Location and Population within AQMA		Traffic Flow and Air Quality		2003/4 Observed		2004/5 Base year	Trajectory
							2005/6	2006/7	2007/8	2008/9	2009/10	2010/11
Lancaster (Action Planning not complete)
City Centre Gyratory Population 455	NOx mg/m3			43		41	41	40.8	40.6	40.4	40.2	40.1
	AADF	NB SB				20200 16190	20200 16110	20031 15941	19862 15772	19693 15603	19524 15434	18024 16934
	7-10am					3620	3560	3445	3330	3215	3100	3427
Preston (Action Planning in early stages)
Ringway Church Street Junction a = North of Junction b = South of Junction Population 105	NOx mg/m3			41		41
	AADF		a b			37180 26130
	7-10am		a b			3250 2230	3250 2230	3250 2230	3250 2230	3250 2230	3250 2230	3250 2230
Blackpool Road Plungington Road a = South of Junction b = East of Junction c = West of Junction Population 38	NOx mg/m3			36		43
	AADF		a b c			8510 13970 11980
	7-10am		a b c			980 1550 1650	990 1565 1666	1000 1581 1683	1010 1597 1700	1020 1613 1717	1030 1629 1734	1040 1645 1751
South Ribble  (Action Planning in early stages)
A59 Liverpool Road Priory Lane Cop Lane(2) a = West of Junction b = North of Junction c = South of Junction Population 155	NOx mg/m3			25(3)		26
	AADF		a b c			28430 2430 8240
	7-10am		a b c			4460 180 1010	4505 182 1020	4550 184 1030	4595 185 1041	4651 187 1051	4687 189 1061	4734 191 1072
London Road Victoria Road Population 134	NOx mg/m3			50(3)		53
	AADF					37950	37580
	7-10am					6270	6260	6260	6260	6260	6260	6260
Leyland Road Brownedge Road a = North of Junction b = South of Junction Population 229	NOx mg/m3			36(3)		38
	AADF		a b			12800 8720
	7-10am		a b			1680 790	1697 798	1714 806	1731 814	1748 822	1766 830	1783 838
Station Road(2) Population 425	NOx mg/m3			32(3)		33
	AADF						17100
	7-10am						1579	1595	1611	1627	1643	1659
Lancashire Combined (Average)
Average Exposure per Resident(4)	NOx mg/m3		DO		42	42	44	46	47	49	51	53
			RR					45	45	43	41	40

Notes
AADF = Annual Average Daily Flow 2 way, except Lancaster which operates as a gyratory
7-10am = Inbound flow only
DO = Do nothing (applies the Lancashire average current rate of air quality change)
RR = Required reduction to satisfy National Air Quality Strategy objectives
⁽¹⁾ Measures include only those indicated in the Lancaster chapter. Further measures that will be included in the developed Action Plan.
⁽²⁾ AQMAs excluded from average exposure calculation as they would artificially reduce overall values.
⁽³⁾ Values estimated.
⁽⁴⁾ Average Exposure per AQMA resident uses the following equation and is applied to each assessed year.

where n = number of AQMA
and Pop = population of each AQMA.

9.7.5 LTP8: Lancaster Mean Resident Exposure Reduction within AQMA

The following table indicates the calculated air quality impacts from packages of work on the City Centre AQMA. The impact of other schemes will be included when the Action Plan is accepted. A number of the identified schemes in the District Chapters have secondary benefits to air quality. In Lancaster, the Heysham M6 link benefits particular corridors including both river crossings but has only a slight impact on town centre movements and air quality.

Table 9.7.5a

Lancaster: Annual Mean Resident Exposure Reduction within AQMA
Package/Scheme	Reduction NOx mg/m3
Heysham M6 Link	0.1
Lancaster City Centre Air Quality Zone	To be determined
Cycling Demonstration Project	0.1
Personalised Travel Planning	0.3
Morecambe West End Neighbourhood Scheme	Not Applicable
Park and Ride	0.4
ITS	Not Applicable
Total	0.9

The above impacts have been included in the ‘do-something’ trajectory which assumes that traffic growth is restrained and that the measures implemented reduce the AADF. The ‘do-nothing’ trajectory assumes the AADF growth will occur at the same rate as per the previous 5 years. Currently this is 0.2% increase per year.

Improvements to vehicle and fuel technology should make an important contribution to the improvement of air quality within AQMAs. However, their contribution is not being relied upon and their benefits are not included. If the technology benefits were taken into account, they would have sufficient impact to meet air quality objectives in a number of Lancashire’s AQMAs.

The following summary table contains Lancaster's observed annual mean exposure concentration and trajectories for both 'do nothing' and 'do something' situations. The 'do nothing' includes a factored Lancashire trajectory as a comparison. The table also includes the percentage change from base year. The year on year changes will be included in the Annual Progress Reports to showing the level of success in achieving the required change that satisfies the air quality objectives.

Table 9.7.5b

LTP8 Air Quality in Lancaster
Annual Mean Resident Exposure Reduction within AQMA mg/m3
	2003/4 Observed	2004/5 Base year	Trajectory						Notes
			2005/6	2006/7	2007/8	2008/9	2009/10	2010/11
Lancaster observed	43	41	N/A						Observed data 2005 not yet available
Lancaster do nothing		41	41.0	41.1	41.1	41.1	41.2	41.2	Observed base value with calculated year on year traffic growth using DMRB
Lancashire do nothing		41	43	44	46	48	50	52	Lancashire average trend factored to Lancaster’s base year
Lancaster do something		41	41	40.8	40.6	40.4	40.2	40.1	Includes the impacts of the identified Lancaster District packages/schemes. Assumes uniform reduction over time.
Changes in Annual Mean Resident Exposure within AQMA % change from base year
		2004/5	2005/6	Trajectory					% Increase per year
				2006/7	2007/8	2008/9	2009/10	2010/11	Min	Max	Ave
Lancashire do nothing		0	3.7	7.3	12.2	17.1	22	26.8	3.6	4.8	4.5
Lancaster do nothing		0	0	0.2	0.2	0.2	0.5	0.5	0.0	0.3	0.1
Lancaster do something		0	0	-0.5	-1.0	-1.5	-2.0	-2.4	-0.4	-0.5	-0.4

9.7.6 Risk Management of Air Quality Projects

Our Risk Management Strategy is described in detail in section 6.2. This overriding strategy will ensure that we deliver our air quality and other targets.

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