Some speed cameras have now been switched on in Northamptonshire and here's where

The Highways England project between Northampton (junction 16) and Catthorpe (junction 19) uses sensors to automatically monitor vehicle numbers and adjust the speed limit via overhead signs, with the aim of tackling congestion, reducing stop-start traffic flow and improving journey times.

Compliance with the display signs is monitored by roadside cameras. Fixed penalty notices and prosecutions for offences committed between junctions 16 and 19 are processed by Northamptonshire Police as the home force.

The operational roll-out of the roadside cameras began in December, with the final ones due to be commissioned at the end of this month (February).

Since the roll-out began, 735 offences have been processed for prosecution. Three of these involve speeds in excess of 115mph, and a further four involve speeds in excess of 120mph. The top speed detected was 127mph.

Matt O’Connell, of the Safer Roads Team, said: “Smart motorway technology is designed to make journeys safer, smoother and quicker. Achieving these benefits relies on every driver obeying the active warning and mandatory speed limit signs whenever they are displayed.

“It’s also important for people to know that even when no speed is displayed, meaning the national 70mph limit is in place, the roadside cameras remain in operation to enforce that limit.”

All funds generated from fines issued on the Northamptonshire stretch of the M1 motorway go to central government.

During an initial three-week test period in November, 2,467 drivers detected by the smart motorway technology received advice letters from Highways England and Northamptonshire Police advising them of the changes and explaining the benefits of smart motorways.

How to drive on a smart motorway, according to police :

- Smart motorways increase the number of vehicles which can use the road, without the need to widen it, by either temporarily or permanently opening the hard shoulder to traffic.

- On the Northamptonshire stretch of the M1, between junctions 16 and 19, the hard shoulder has become a fourth driving lane.

- On a smart motorway, traffic flow is constantly monitored by sensors which automatically change speed limits to help keep traffic flowing freely.

- The regional traffic control centre monitors what is happening on the road and responds to incidents. It can set lane control and speed limits and deploy resources to manage incidents.

- Lanes can be closed, indicated by a red X on the overhead signs, for a number of reasons – there could be debris in the road or a person or animal on the road. There may be an accident or breakdown ahead, or the lane may be needed by the emergency services.