Monday, April 3, 2017

News: Restricted speed limits on M1 set to stay

By

Users of the M1 through Rotherham will be restricted to travelling at lower than 70mph during peak times in an effort to address air quality issues.

The M1 smart motorway is now operational and open to traffic and the section has been designated as Britain's first ever Air Quality "Speed Limit" based motorway.

Highways England has been working on the £106m scheme on a ten mile stretch of the M1 between junctions 32 (south of Sheffield and Rotherham) and 35a (north of Sheffield and Rotherham).

A 20 mile stretch of the M1 between junction 28 (South Normanton) and 31 (Aston) is also benefiting from a smart motorway project costing £205m where four lane running began last year.

The projects include converting the hard shoulder to an extra traffic lane in both directions and variable mandatory speed limits and they deliver benefits at a significantly lower cost than conventional motorway widening, and with less impact on the environment during construction.

Advertisement

In 2014, the Transport Secretary put the brakes on the Highways Agency's (now Highways England) plans to implement a maximum mandatory 60mph speed limit. The speed limit would have been used between 7am and 7pm, seven days a week, to manage traffic speeds and help reduce congestion and air pollutants locally.

It was said at the time: "The Secretary of State has not accepted this approach as the Government's preferred option for managing local air quality on the M1 and tasked Highways England to identify other measures which achieved the necessary reduction. Speed restriction is to be used only to the extent that is absolutely necessary."

Now, the Highways Agency has said that this section of the M1 "is now Britain's first ever Air Quality "Speed Limit" based motorway" and that speeds are set daily between 7-9am and 3-6pm.

The section between junction 32 (M18) and junction 35 (A616) carries more than 110,000 vehicles each day and suffers from congestion and delay at peak times.

Environmental assessments carried out on the managed motorway schemes through the Sheffield city region showed there was likely to be an adverse impact on local air quality if the motorway continued to operate at the national speed limit (70mph).

There are nine Air Quality Management Areas (AQMAs) in the stretch of motorway. These areas are declared where the EU limit and Government standards adopted for Nitrogen dioxide (NO2) and dust particles are not being achieved.

Modelling in 2015 showed that the maximum increase in NO2 concentration as a result of the 70mph all lane running on the M1 would be Brinsworth, west of J33. The increase in NO2 is as a result of an increase in flow of approximately 4,800 vehicles per day on the motorway in the area.
Restricting speeds to 60mph at peak times was "considered as not resulting in significant adverse air quality effect" although NO2 levels will still increase at some areas, especially between junction 33 and 34.

A total of 85 sensitive receptors were predicted to be in exceedence of annual mean NO2 objectives with 70mph all lane running. 52 sensitive receptors are still predicted to be in exceedence with the mitigated operating regime of 60mph at peak times.

It is hoped that the mitigation will improve speeds, reduce congestion and therefore reduce emissions from vehicles travelling on the motorway.

The 2015 report said: "The mitigation will remain in place until the results of the air quality monitoring and further assessment indicate that air quality has improved sufficiently to allow a switch to a standard SM-ALR [70mph] operation. However, Highways England is continuing to see if other mitigation options can be developed that would allow the scheme to operate at the national speed limits at all times by the Opening Year of 2017. Imposing speed control will only be used as a last resort."

Some scheduled maintenance is planned on this stretch of the M1 over the coming months, which includes minor resurfacing works and installing further roadside technology.

Highways England website

Images: Highways England


0 comments:

Members:
Supported by:
More news...

  © Blogger template Newspaper III by Ourblogtemplates.com 2008

Back to TOP