Major A1 Closure in Cambridgeshire for Flood Prevention Works

Motorists in Cambridgeshire are being urged to plan ahead as part of the A1 near Kelpie Marine will be completely shut from Friday, September 19, to allow for a significant programme of drainage improvements.

The closure is required so that National Highways can install a new culvert beneath the road surface. The engineering team says the upgrade is critical to protecting the busy route from flooding, which in recent years has increasingly disrupted traffic during periods of heavy rainfall.

Why Culverts Matter

Culverts are underground structures that act as channels for streams, drainage ditches, or surface water. By moving water underneath the carriageway, they prevent it from pooling on the surface or undermining the road foundations. Without them, stretches of major highways such as the A1 would be at risk of damage, erosion, or prolonged closures after storms.

A spokesperson for National Highways said:

“This project will strengthen the resilience of the A1, making it safer and more reliable for drivers. The new culvert will manage water more effectively and reduce the risk of future flooding incidents in this area.”

Diversion Details

During the closure, drivers heading northbound will be diverted:

• Off the A1 at Tempsford

• Along St Neots Road, joining the A428 at St Neots

• Rejoining the A1 at the Wyboston junction

  
  

Southbound traffic will use the same route in reverse. Signs will be in place to guide vehicles, though National Highways is advising motorists to allow extra time for their journeys, particularly during peak travel hours.

Local Reaction

Residents and local business owners say they understand the need for the works but are bracing themselves for delays.

Cllr Sarah Whitmore, who represents the nearby ward, said:

“The A1 is a vital route for commuters and freight, so any closure has a real impact. But flooding has been a serious issue here, and fixing the drainage once and for all will benefit everyone. I’d ask drivers to be patient and plan their journeys carefully.”

Local café owner James Holloway, whose business sits just off the diversion route, noted:

“We’ll definitely see more traffic through the town while the A1 is shut. That can be challenging for locals, but it could also bring in extra customers. I just hope drivers stick to the official diversion and don’t cut through smaller village roads.”

A commuter from St Neots, Emily Carter, added:

“I travel to Bedford for work every day, and the A1 closure will probably add 20 minutes to my journey. It’s frustrating, but I’d rather put up with a few days of disruption than constant problems with flooding every winter.”

Part of a Wider Programme

The works form part of a wider programme of resilience improvements across England’s Strategic Road Network. Rising rainfall levels and more extreme weather events are increasing the pressure on drainage systems, with National Highways investing in culvert upgrades, flood relief schemes, and surface water management to future-proof major routes.

The organisation said the timing of the closure was chosen to minimise disruption, with the aim of reopening the A1 section as quickly as possible once the culvert is in place.