Construction work on Castle Street improvements to begin in February
Work to make the temporary road layout and cycleway on Castle Street permanent will begin at the end of February, following site surveys and removal of the traffic islands on Kingsway.
Initial work will start on February 2nd, focusing on required surveys and preparation of the site. The main phases of the project will begin on February 23rd and are expected to take around 52 weeks to complete.
The current configuration of the traffic lanes on Castle Street will not change, so there will be no loss to the number of traffic lanes.
Following detailed assessments, Castle Street needs to remain open to traffic, otherwise there will be a disproportionate impact on the wider highway network.
The impact would include:
- An impact on journey times for all bus services entering and leaving the Cardiff Bus Interchange via Westgate Street and Customhouse Street
- An additional impact on traffic levels on Central link and the Eastern Bay Link Road given the current closure of Hemingway Road
- The additional impact on wider network given that the Butetown Tunnels and Gabalfa Roundabout are running at capacity during peak periods
The reallocation of highway space for the Cardiff Crossrail. By introducing a tram system, it means that there isn’t any spare capacity for displaced general traffic.
Key features of the permanent scheme include:
- A fully segregated, permanent cycleway built to Active Travel standards
- Carriageway resurfacing throughout the route
- Upgraded footways and paved areas
- Changes to the bus stop area on Kingsway/North Road
- Measures to support improved air quality, including traffic management changes, enhanced bus infrastructure, green‑roof bus shelters, and additional landscaping.
In 2018, air pollution levels on Castle Street breached the European Ambient Air Quality Directive and Cardiff Council was legally directed by Welsh Government to develop a Clean Air Plan to reduce Nitrogen Dioxide levels on this street.
A new road layout was trialled to help meet these legally binding air quality limits as quickly as possible. This temporary scheme included:
- Reducing traffic lanes from three to two
- Retaining the westbound bus lane
- Installing a two-way, pop-up cycleway
Since these changes were introduced, air pollution levels on Castle Street have met all required air quality standards, with Nitrogen Dioxide levels reducing from 45 µg/m3 to 29 µg/m3.
Cllr Dan De’Ath, Cabinet Member for Climate Change, Transport and Strategic Planning, said:
“The temporary scheme on Castle Street has been in place for several years, and we have demonstrated that the revised layout has significantly reduced NO₂ levels, ensuring we remain legally compliant with all air quality standards.
“Since the Clean Air Plan was introduced in 2019, the pandemic has intervened, during which time Castle Street was closed to traffic and temporarily operated as an outdoor café space. When we consulted residents on whether the road should remain closed or reopen, more than 50% supported reopening.
Construction work on Castle Street improvements to begin in February