DMUG 2016 - Nigel Bellamy, Highways Agency

DMRB - Air Quality

Nigel Bellamy

DMUG 2016

Outline

Highways England Guidance

DMRB Assessment Best Practice

– Traffic Data

– Monitoring

– Modelling

New DMRB AQ Model Tools Overview

Highways England Guidance Updates


Timeline since HA207/07

20092007 2011 2012 2013 2014

DMRB AQ

Chapter

HA207/07

LAQM (TG09)

IAN 170/12

Long Term

TrendsIAN 174/13 Advice

on Significance

EFT v4 EFT v5

Defra’s Report

on NOx & NO2

Trends

2015

IAN 185/15 Link

Speeds & Speed

Bands released

IAN 175/13

Compliance Risk

Assessment

EFT v6EFT v5.2

2016

LAQM

TG(16)


• Drive early collaboration between Traffic and AQ Teams;

• Identify risks at an early stage;

• Work to mitigate risk where possible, although this is an ongoing process

through the assessment;

• Monitoring to inform risks and to evaluate mitigation measure effectiveness;

• Proportionality of assessment whilst ensuring assessment is Robust;

• Right modelling for the assessment.


• Needs to be more Risk Based;

• Guidance to include flow charts to aid the user in relation to what the

assessment requires;

• Ensure that the AQ assessments are proportionate to the risk;

• Greater emphasis on mitigation.


DMRB Assessment Best Practice Traffic Data

• Fit for purpose

• Study Area

• Time Periods

• Scenarios

• Data Requests

• Check & Challenge


Monitoring

– Programmed early

– Critical to verification

– Targeted coverage

• AQ Risk

• Dispersion characteristics

• Gradients

• Backgrounds

• Habitat sites

• Co-location

Targeted coverage

– On-going review


Monitoring Safety

– Risk Assessments

– Working at Height

– Lone Working

– Chapter 8

– MAC Inductions

– Weather

Bad site pic


Air Quality Modelling - Emissions

– Diurnal emissions profile important

– Meteorology vs emissions

– Traffic flows vs HDVs

AM: 07:10:00

IP: 10:00 – 16:00

PM: 16:00 – 19:00

OP: 19:00 – 07:00



– 4 Periods

– Temporal emissions profile

– Direct representation of traffic models

– Enables mitigation modelling

AM: 07:10:00

IP: 10:00 – 16:00

PM: 16:00 – 19:00

OP: 19:00 – 07:00

AM: 07:10:00

IP: 10:00 – 16:00

PM: 16:00 – 19:00

OP: 19:00 – 07:00

AM: 07:10:00

IP: 10:00 – 16:00

PM: 16:00 – 19:00

OP: 19:00 – 07:00

AM: 07:10:00

IP: 10:00 – 16:00

PM: 16:00 – 19:00

OP: 19:00 – 07:00



– Emissions & Highways England Speed Bands

– Recognition that model speeds are uncertain

– Professional judgement on application of bands by traffic team


Air Quality Modelling - Receptors

– What to include?

– Use appropriate OS data

– IAN174/13 Significance criteria requires

ALL receptors in exceedence to be

included


Air Quality Modelling - Verification

– Model performance over large study areas can vary.

E.g. Motorway / Urban roads / Hotspots

– Highways England apply zonal verification where model

performance groups can be identified

New DMRB Tool Overview


• Updates the current version and will be more sophisticated;

• Contains the latest emission factors and speed band methodology;

• The outputs of the model have been validated at a large number of

sites in the UK;

• Allows input of detailed temporal traffic breakdowns (AADT, AAWT &

Period Flows);

• A GIS interface will allow the user to input receptors and roads.


Speed Bands

AADT

AAWT

AM, IP, PM & OP


• Draw Road – draw new roads as lines

• Edit Road – edit road positions

• Draw Receptor – draw new receptors as points

• Edit Receptor – edit receptor locations

• Draw Junction – draw junctions

• Edit Junction – edit junction locations

• Select Layer – Selects Layer in GIS for editing

• Delete – select and delete roads or receptors

• Roads – review all user defined roads and their associated receptors

• Audit – calculate distances between all roads and receptors and ascertain which roads are close enough to

receptors to have an influence on air quality. Enables a review of roads and junctions that influence each receptor.

• Export – export your roads and receptor data in a format to enable direct importing into the DMRB air quality

model

• Import – enables visualisation of air quality model results

Highlighted receptor – associated roads are shown in yellow on map and in table.Select whether to include as source.


Source selection & auditing – by receptor

Selected road is highlighted in yellow

All receptors within distance threshold highlighted in red.


Source selection & auditing – by road

Thank you & Questions

Environment

DMUG 2016 - Nigel Bellamy, Highways Agency