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Hydrock Beats the Traffic in Truro

Click here to view the 'Hydrock Beats the Traffic in Truro' video.

Traffic considerations are often a major stumbling block to obtaining planning permission for development, particularly in built-up areas with existing congestion issues.  Using sophisticated digital traffic surveying and modelling tools, Hydrock Byways and Highways (HBH) transportation consultants can demonstrate the impact that new highway schemes can have on the local highway network in a way that a layperson can understand without the need to read a detailed report.

To support their planning application for the Maiden Green mixed-use scheme in Truro, supermarket giant Asda and Walker Developments needed to demonstrate to the Highways Authority that any increase in traffic volume could be mitigated to a degree through highway improvements.  The scheme included an Asda supermarket, approximately 400 residential units, 150 student units, a local district centre and  the Innovation Centre, a new medical research establishment associated with the Royal Cornwall Hospital, Treliske.

Maiden Green (1) is situated on the northern side of the A390, immediately to the West of the Royal Cornwall Hospital (2), adjoining the current industrial and commercial development at Treliske (3) with Truro College (4) to the South. It covers an area of approximately 100 acres (43 ha). 

Royal Cornwall hospital traffic alone accounted for between 1500-2000 eastbound vehicle trips per day passing through the Richard Lander signal junction (5), through the Maiden Green Roundabout (6) and onto the well-known congestion hotspot at Treliske Roundabout (7). 

HBH commissioned a specialist survey team to install traffic cameras over three miles along the A390 corridor between Threemilestone roundabout and Arch Hill which monitored traffic flows over a 48hr period in February 2010 and then this real-time data was plugged into the Paramics micro-simulation modelling programme. 

As part of the development proposal, HBH have designed a new road scheme which will provide a new northern route into the hospital from a proposed high capacity, signalised roundabout junction to be constructed at the existing Richard Lander junction. The effect of this is to divert up to 2000 eastbound hospital related trips through the development site and into the hospital, therefore freeing up a significant stretch of highway between the Richard Lander signal junction and Treliske roundabouts, providing significant highway gain as part of the development proposals. This proposed northern route was highly supported by hospital staff and the Local Highway Authority in the recent public consultations organised by Walker Developments and HBH.

By modelling the proposed scheme in Paramics, using real-time traffic flows, and comparing it to the existing local highway network, HBH was able to demonstrate that a large proportion of the traffic generated by the new development could be mitigated by the highway improvements proposed.