An independent survey commissioned by the Council to forecast future NO₂pollution levels in the city has identified just one street where EU legal limits are likely to be breached in future years.

The survey, carried out by industry experts Ricardo, follows similar studies undertaken in several major British cities. It shows that only Castle Street, which runs in front of the castle from Westgate Street to Duke Street, is likely to fail legal compliance beyond 2021 if nothing is done to reduce traffic pollution.

The Council now has until June next year (2019) to work up a plan to reduce the pollution levels on Castle Street in the shortest possible time and to ensure that legal limits of NO₂are not breached by 2021.

Councillor Caro Wild, Cabinet Member for Strategic Planning and Transport, said: "The news that one road in the city could breach legal limits if we don't take action is concerning. Many other cities across the UK are discovering that the air their residents breathe is heavily polluted due to high concentrations of fumes from diesel vehicles.

"Although only one road in Cardiff is modelled to breach legal limits by 2021, this doesn't mean to say we don't have a problem in the city, we do. Welsh Government have made clear that there is no known safe level of exposure to NO₂or particulate matter air pollution, or for short-term exposure to it. The effects of exposure increase the longer someone is exposed and studies have shown that it is responsible for increased rates of lung disease and cancer.

"Air pollution on Castle Street is the symptom of a wider problem which extends far beyond this stretch of road. We may be within legal limits across the city, but the cleaner we can make the air the better it will be for everyone. We will now look at introducing a range of measures, which will not only fix the problem on Castle Street, but which will also help make the air we breathe across the city cleaner. The council will be calling on Welsh Government for the necessary funding to bring these measures into place as soon as possible.

"Although the modelled data which is required under the EU Directive has only indicated that Castle Street is in breach of the required level, the Council also has a number Air Quality Management Area (AQMAs) in place where the level of roadside nitrogen dioxide (NO₂₎is approaching and in some locations exceeds the limits required by law.

"Within the City Centre AQMA and in particular Westgate Street, our own latest monitoring at residential locations showed an annual average value of 38.2 micrograms per cubic meter. There are other locations in and around Westgate Street, where levels of NO₂are also a cause for concern, so it is clear that Castle Street isn't the only problem in the city centre.

"As the Welsh Government has stated, air quality levels which are barely compliant with the objectives is not ‘clean' and still carries long term health risks. Advice has been given to keep levels as low as ‘reasonably practicable.' An interim action plan is in place on Westgate Street, but the long term measures which are being proposed to reduce the level on Castle Street, should in turn significantly reduce the levels on other streets in the city centre, including Westgate Street in particular."

Following a legal challenge by Client Earth on the Welsh Government, Cardiff Council was legally directed to carry out a feasibility study to assess which city streets would fail legal pollution levels beyond 2021 if no action was taken to reduce pollution.

As part of the next phase of the study, Welsh Government has requested that the Council benchmark any measures it wishes to introduce to reduce NO2 pollution against the effectiveness of a charging Clean Air Zone. If a charging Clean Air Zone reduces pollution to below legal limits in the quickest time then the Council may have to consider this as the preferred solution.

The legal limit is set at an annual average limit value of 40 micrograms per cubic metre. Polluted air is estimated to cause the equivalent of 40,000 deaths each year across the UK and average life expectancy is estimated to be reduced by 7-8 months due to air pollution.

As part of the next phase of the Feasibility Study a number of measures to reduce NO2 pollution across the city are being assessed by the council including:

        Implementing further speed restrictions, enhancing the established 20MPH limit areas;

        Development of the cycling superhighway infrastructure and the expansion of the Nextbike scheme;

        Increasing the number of zero emission buses on Cardiff's network;

        Improving the taxi licensing policy to set minimum vehicle emission standards;

        Improving access for public transport, cyclists and pedestrians from the new bus station and the roads within the city centre loop;

        Increasing the number of bus lanes to encourage public transport and make travel by bus quicker and more reliable;

        Accelerating Park and Ride programmes in the North West and North East Cardiff;

        Improving and promoting the uptake of low-emission vehicles by investing in Cardiff's electrical charging infrastructure.

Cllr Wild said: "We will now model interventions to find the quickest way to solve the problem on Castle Street and to reduce pollution levels elsewhere.

"We will need Welsh Government's full financial backing to reduce NO2 pollution. In the meantime there are immediate things we can all do to help. I would urge people to begin by reducing their reliance on private cars, and where feasible move towards other forms of sustainable transport, such as walking, cycling or public transport. The figures speak for themselves, traffic is responsible for around 80% of NO₂measured at the roadside so we need to change the way we do things

"If we can shift the way people move around the city - and we have plans to make public transport easier and more efficient while improving cycling and walking options - then we can all help to make the city healthier while reducing pollution and congestion on our roads."

At a Cabinet meeting on November 15^th, the Cabinet will be recommended to approve the Clean Air Feasibility Report and to allow work to begin on assessing the impact of any proposed measures to reduce air pollution benchmarked against a charging Clean Air Zone. The benchmarking against a charging Clean Air Zone is a Welsh Government requirement designed to determine which will reduce pollution quicker.

The legal direction that has been given by the Welsh Government gives a specific timeline. So far Cardiff Council has submitted the initial scoping proposals and the feasibility study. The final plan (business case on our preferred option) has to be submitted to Welsh Government no later than June 30^th2019. This will enable the Council to apply for funding to introduce measures to reduce pollution to below legal requirements as quickly as possible.