The Welsh Government wants to hear your views on their final package of measures to improve air quality on the A483 – that could see the recent temporary 50mph limit become permanent, and even enforced by average speed cameras.
At the end of July the Welsh Government published an interim supplemental plan for tackling roadside nitrogen dioxide concentrations that were aimed at achieving compliance in the shortest possible time with limit values for nitrogen dioxide (NO2) at five locations on the motorway and trunk road network in Wales – one of which being Wrexham.
As a result there was an immediate implementation of temporary 50mph speed limit on the stretch of the A483 between the Gresford Roundabout and the B&Q Roundabout.
The consultation on the final package of measures for improvements to air quality, known as WelTAG Stage Three, is further to the consultation exercise that took place back in April 2018 on the Stage One and Stage Two findings. It will also look for opinions on the 50mph speed limit, and has a special document dedicated to the A483 by Wrexham.
The study corridor considered in the report covers the ‘principal corridor’ on the A483 between J5 (Mold Road Interchange) to J6 (Gresford Interchange).
Several mix and match measures are discussed, with the key items being distilled into three option sets.
A special £30,000,000 barrier is suggested ‘with or without special surfacing at sensitive locations’, along with implementing a closure of the southbound off-slip at Junction 5 and the northbound on-slip at Junction 6.
A £6,000,000 ‘advisory variable diversion’ route for local traffic, utilising other routes including the A5152 Chester Road, through signage to reduce cars on the A483 during the AM and PM peak hours is outlined, but notes: “Wrexham CBC may have concerns over using alternative routes during periods when NO2 levels are highest, as the A5152 and A541 Mold Road run towards and through the town centre.
“Cost estimate takes into account the equipment needed, ongoing maintenance and an estimate for measures that the Council may want implemented on the local road network and the prescribed ‘diversion’ route.”
The likely measure, and significantly cheaper option, is the enforcement of the reduced speed limit.
This is described as the “introduction of a new speed limit on the A483 between Junction 5 (Mold Interchange) and Junction 6 (Gresford Interchange) and enforce through average speed cameras.”
The £275,000 price tag will include average speed enforcement cameras and equipment, traffic signs and ongoing maintenance. The cost estimate takes into account the potential requirement to place cameras at junctions and slip roads (although mainline enforcement only may be appropriate) and the Police back office costs, which Welsh Government may be expected to cover.
The cost could drop, as the report notes the scheme has “…the potential to reduce in cost, as the proposal is to have average speed enforcement cameras operational as part of the ongoing trial and (most likely), ‘permanent’ sign installations.”
Any cameras would also be linked to Automatic Number Plate Recognition systems, with the report saying: “In addition to the classified link count data, there would be significant benefit in undertaking ANPR surveys.
“This data can be linked back to the DVLA database to determine not only vehicle classification, but also emission standards of vehicles.
“The data could be used to identify the rate of change of the fleet towards cleaner, newer, low emissions vehicles and could be used to evidence the need for additional measures to accelerate the rate of change, e.g. a scrappage scheme.”
The air quality baseline for the A483 has been derived from a combination of national modelling and monitoring undertaken by the council, and Welsh Government. Aside from the modelling, the report notes on Wrexham Council monitoring: “The closest monitoring stations to the section of the A483 under consideration are locations 20 and 32 on Chester Road. Concentrations at these locations are well within the air quality objectives but the sites are too distant from the A483 to assess whether the PCM modelled concentrations are consistent with local monitoring.
“The only location close to the A483 at which WCBC monitors air quality is location 30 (Rhostyllen Roundabout), where concentrations are just within the air quality objective.”
Welsh Government has commissioned air quality monitoring along the A483 study corridor. The monitoring is currently undertaken using diffusion tubes, at 6 roadside locations and 1 background location. At each site, the monitoring consists of triplicate diffusion tubes, exposed for ~2week durations. Data for 6 months (12 exposure periods) is currently available. The roadside monitoring is undertaken at a distance of between 2 and 15m from the side of the A483, at a height of approximately 2m above the carriageway – date below.
Transport Secretary Ken Skates said: “The contribution made by the environment to good health cannot be overstated. Tackling poor air quality is a priority for the Welsh Government, reflected in our national strategy ‘Prosperity for All’. We will reduce emissions and deliver vital improvements in air quality through planning, infrastructure and regulation measures.
“Alongside the other devolved administrations, we’re working actively to meet our joint objective with the UK Government to transform the UK’s most polluted towns and cities into clean and healthy urban spaces, supporting those most directly affected.
“We now need your views on the proposed final measures to achieve compliance within the shortest possible time with the limit values laid down by the Directive and Regulations at each of these five locations.”
Minister for Environment, Hannah Blythyn, said: “I welcome people’s views on these proposed measures, which aim to reduce nitrogen dioxide levels to within legal limits in the shortest possible time. It’s important to remember the main reason for taking this action, which is to improve air quality and reduce the harmful effect vehicle emissions can have on people’s health and well-being.”
The Welsh Government report added that you are likely to see lots of communication on this topic, “There will be a significant communications campaign made on the likely measures using social media, radio and signs on the network.
“This campaign will be reiterated at key times on an ongoing basis along with key announcements made on the air quality results”.
Welsh Government would like to hear your views via this link: https://beta.gov.wales/tackling-roadside-nitrogen-dioxide-concentrations-wales-weltag-stage-3.
For reference there are two speed data graphs that we are reproducing as they may be of interest to some readers!
“This data shows that speeds remain reasonably consistent throughout the day in both directions, with no noticeable reduction during either the AM or PM peak periods. The average speeds observed on the Southbound corridor are approximately 62mph at 08:30, midday, and 17:00.
“Similarly, speeds on the Northbound carriageway are approximately 63mph at 08:30 and midday, and 66mph at 17:00. This data suggests that the road is free-flow throughout the day. Speeds are shown to reduce during the off-peak period, with average speeds reducing to around 57mph on the Southbound and 56mph on the Northbound corridor. The fastest speeds occur following the PM peak hour, with vehicles averaging around 66mph at approximately 18:00 in both directions.”