Innovative trial to go ahead to improve state of fens roads

A trial project to explore innovative ways to better maintain roads which run over fen soils will now progress. 

The Fen Roads Trial, proposed by Cambridgeshire County Council, was backed by the Combined Authority Board on Wednesday (Nov 13) and a business case for the project will now be developed. 

The £1.5 million trial proposes to test innovative solutions to help keep the roads in good condition for longer.  

It is estimated that more than 40% of Cambridgeshire’s roads lie on peat-based soils, which expand and contract significantly as they become saturated and then dry out. Extremes of hot, dry and wet weather are becoming more frequent with climate change, resulting in higher levels of road damage. Many routes are well known for their uneven or damaged surfaces. Some well-used routes now require traffic management, speed limits and safety signing to help make them safe. 

The trial aims to test solutions on the same stretch of road and compare their performance. Potential trial sites are: 

• B1104 Prickwillow Road Isleham, East Cambridgeshire.  

• B660 Holme Road, Ramsey St Mary’s, Huntingdonshire.  

• B1040 Herne Road, Ramsey St Mary’s, Huntingdonshire. 

The trial aims to tackle the issue at the road foundation level, to bring about more long-term improvements and reduce ongoing cost. Cambridgeshire County Council and Peterborough City Council are the region’s highways authorities, responsible for maintaining roads.  

Many trial methods are proposed, including: 

• Excavate and fill using a lightweight recycled fill product. 

• Deep soil stabilisation for underlying soil (peat in this case) up to five metres below the existing road level. 

• Ex-situ recycling, creating a flexible road. This approach treats the road itself like a quarry, breaking down the existing surface and using every bit of it to build a brand new one.  

Separate work to investigate the cost of maintaining and upgrading roads which run on fen soils is going ahead this financial year. This work, called an Economic Impact Assessment, will sit alongside the Fen Roads Trial to improve how those routes are managed. 

The trial also supports the recently approved Shared Ambition for Cambridgeshire and Peterborough’s future and in particular its focus on innovation, better connectivity and helping the region stay resilient to future change.  

Mayor Dr Nik Johnson said: “This innovative trial is a vital step forward in addressing the unique and growing challenges of maintaining fen roads. So many rely on these roads daily, and we want to help make sure they are decent, safe, and ready to serve our road users well into the future.”  

Peterborough City Council are planned to sit on the project board of the trial. If successful, any methods could be applied in other areas with similar challenges, like in Norfolk and Lincolnshire. The trial can also be used to support bids to Government for funding for fen roads.