Paul Basham Associates prepared a Transport Assessment and Travel Plan on behalf of Redlane Ltd to support the development of the site to provide new light industrial business park accessed directly onto the A27 in Southampton.
The Brief
Paul Basham Associates were approached to support an outline application for up to 5,905m2, in particular to consider the acceptability of proposed access arrangements onto the A27 (a detailed part of the application) and to assess the impact of the development on the local highway network.
Our Approach
Given the nature and location of the proposals the main consideration from a highways perspective was the potential level of impact on the operation of the local highway network as a result of trips generated by the new commercial units from this largely greenfield site and the suitability of the access arrangements.
In the first instance we undertook a site visit to review the local highway network and to confirm the most appropriate location for the site access. This was complemented by a 7 day speed and volume traffic survey on Kanes Hill (A27). The results of the site visit and speed survey confirmed that the site access should be located to the south of the existing access in order to maximise visibility and also that a right turn lane was unlikely to be needed to support the development. To confirm the suitability of the arrangement a Stage 1 Road Safety Audit was commissioned on our access design which raised no issues.
To assess the impact of the development on the local highway network the anticipated trip generation was calculated on the basis of the site coming forward as all B1 use in order to provide a robust figure. Census data was then used to determine the likely distribution for traffic from the site access towards either the St Johns Road/Kanes Hill junction to the south or the Kanes Hill roundabout to the north. The St Johns Road/Kanes Hill junction was assessed using industry standard modelling software whereas the impact on the Kanes Hill roundabout was considered on the basis of the relative increase in traffic as a result of the development when compared to existing flows.
Following Hampshire County Council’s consultation response the Kanes Hill roundabout was re-assessed using junction modelling and, whilst the impact was not demonstrated as ‘severe’, Hampshire County Council did request a contribution towards potential improvements at this and the St Johns Road/Kanes Hill junctions. Following liaison with highways officers through meetings, emails and telephone discussions a revised assessment was agreed and the contribution amount required was reduced by over a half.
The Result
Following liaison with Hampshire County Council’s highways officers and agreement on the required contribution value the site received a resolution to grant consent at planning committee in June 2019. The site will deliver important employment land within Eastleigh Borough, supporting the Local Plan and economic growth in a part of the country which Paul Basham Associates know very well.