A30 – Chiverton to Carland Cross

The A30 Chiverton to Carland Cross upgrade delivered 8.7 miles of new dual carriageway and 14 structures across Cornwall, with Wentworth providing coordinated temporary works and geotechnical support throughout the three‑year programme. We ensured consistent engineering across dispersed sites while keeping traffic flowing on this strategic route. 

A key challenge involved constructing a new 32‑metre bridge just five metres from an operational 1970s structure. We developed tightly controlled construction sequences that managed plant movements, excavation and formwork within extremely limited space. 

Across all 14 locations, Wentworth delivered tailored geotechnical designs and introduced a lattice‑tower reinforcement method that removed the need for extensive temporary formwork, accelerating abutment construction. The temporary works also supported extensive prefabrication, with lifting checks and rapid‑installation schemes designed for short possession windows to minimise disruption. 

The scheme opened in 2024 with key outcomes: zero harm across 4.5 million hours, compressed construction timescales, continuous traffic flow and seamless coordination between Costain, Keltbray and design teams. The temporary works were nominated for the ICE South West Civil Engineering Awards 2025, recognising innovation and delivery excellence.  

Key Facts 

• 8.7 miles of new dual carriageway alongside existing A30 
• 14 bridge structures provided with temporary support systems during construction 
• 32-metre-span bridge built 5 metres from operational 1970s bridge 

What we stand for