Collated notes regards Dumbreck Road traffic impacts and proposals

02 April 2021

  1. Overview
  1. Classification

Dumbreck Road is classified as a main distributor road, which is a road which carries an expected higher traffic flow compared with a residential road. The road width, with dual lanes, will assist with traffic flow and limit the build-up of traffic, which would be a consequence of single lanes. There are no restrictions on the type of traffic that use a public road, other than weight restrictions, where weight is an issue, or height restrictions, where height is an issue.

  • Traffic volumes

The volume and type of vehicles using Dumbreck Road was recorded both before and after the ‘Use The Loop’ campaign, to assess its impact. Please find attached a spreadsheet I’ve put together using the recorded data. There were two survey sites. Site 1 was located to the north of Nithsdale Road and site 2 to the south of Nithsdale Road. The initial set of surveys were taken over a 3 day period, from Tuesday the 1st to Thursday the 3rd of May 2018. The second set of post campaign surveys were taken at the same sites again over a 3 day period, this time from Tuesday 19th to Thursday 21st March 2019. From the surveys it is evident the campaign did not reduce vehicle numbers but will have made thousands of drivers aware that there is an alternative route. The surveys show there was a negligible increase in northbound traffic however the amount of southbound traffic increased by almost 1000 vehicles per day. These surveys also show that the daily amount of vehicles using Dumbreck Road is roughly 13,000 northbound and 10,000 southbound. Having checked, we’ve been unable to find any regulations or guidance that specify the maximum number of vehicles permitted on a public road.

  • Specific impacts
  1. Road safety

With regard to the safety of a road, one of the key factors is the injury accident history of a road. This is done by checking Police Scotland records. Obviously a road with a significant history of such accidents would suggest there is a road safety problem and would be investigated. Please note we don’t check non-injury accident data as this data is not representative since not all non-injury accidents are reported. Given the volume of traffic that uses this road (see below), I can advise that according to Police Scotland, there has only been 1 recorded injury accident on Dumbreck Road in the last standard 3 year period. It occurred at the traffic signals on the northbound carriageway opposite the M8 westbound off ramp and involved a vehicle accelerating away from a red light into the rear of the vehicle that was in front of it.

  • Noise impacts

I recall the Community Council also raised an issue about road noise. I can advise that, according to the UK Government website, “There’s no legal limit to road noise, although noise levels might be taken into account when new roads or houses and offices near roads are planned.

  • Air pollution impacts

GCC don’t have significant concerns in terms of air quality in the Dumbreck Rd area. Monitoring at a “worst case” location in the street, roadside location close to traffic lights at which vehicles may queue, has provided the results shown in the table below.

 Annual Mean Nitrogen Dioxide (ug/m3)
Dumbreck Rd242723

Recorded levels of NO2 are significantly below the Scottish air quality objective for this pollutant which is set at 40ug/m3. Monitoring will continue to ensure that any changes in pollution levels are identified and action taken as necessary.

We only currently monitor for NO2 at this location. Accurately monitoring for particulates requires the use of reference grade equipment in an automatic monitoring station which we do at nine locations across the city. No monitoring station in the city has recorded an exceedance of particulate objectives for several years, including those in greater traffic related pollution environments than Dumbreck Rd.

We can therefore state with a high degree of confidence that all particulate objectives are likely to be met in this area.

  • Vibration impacts

A vibration survey has been agreed at 1 location. The occupier does not want it undertaken until traffic volumes return to normal.

  • Road condition / defects

Safety inspections of Dumbreck Road are undertaken on average 12 times per annum. In addition, routine inspections are undertaken in response to notification or reports of a known defect. Please note that the most effective way of reporting carriageway and footway defects is through the Roads and Lighting Faults (RALF) reporting line on 0800 37 36 35. The reporting line is open 24 hours and 365 days

  • Suggested solutions
  1. Capacity reduction to single lane in either direction (proposed by DCC)

I note the Community Councils request to consider a further reduction of capacity by reducing all of Dumbreck Road to a single lane in both directions. Given that in both directions it’s already been reduced down to one lane at individual points, such a proposal may not have that big an impact on the number of vehicles using this road. This means a similar number of vehicles using the road would take longer to get through and therefore increase pollution levels.

  • Use of a charging order to cover use as a motorway connector (proposed by JM)

With regard to a ‘charging order’ or an order that targets specific vehicles and at / or at specific times of the day, I’ve got no experience or knowledge about this. This sounds like a toll road or something similar. In Glasgow we’ve only ever targeted vehicles for their weight, length, width or height, none of which are applicable to Dumbreck Road because there’s nothing there to physically justify such restrictions i.e. no low bridges or weak bridges. Also, because Dumbreck Road is the diversion route for motorway closures, I can’t see how Transport Scotland would support such proposals.

  • Revisit / enhance Use The Loop campaign (proposed by JM)

I would say the Use the Loop campaign did achieve one objective and that was to ‘inform drivers’ or ‘make them aware’ that there was an alternative route (although we can’t provide evidence of this other than the radio campaign reach = 1000’s drivers).

The Police reviewed the engagement programme that they agreed to in principle and when they actually got around to looking at it, from a practical point of view, stopping HGVs on Dumbreck Road, there wasn’t really any suitable or safe way to do this. Our Road Safety team did drop 100’s leaflets to every small/medium/large business in the area. The main issue here is that drivers just tend to choose the route that’s least busy at the time or most convenient to their planned route dependent on the time of day.

Other options, perhaps video the area for a week, take a note of all the names on the trucks and write to them all, asking them to consider using the other route. The problem here could be GDPR and potential data protection issues.

Also, maybe signage/advertising on Dumbreck Road itself (as opposed to the approach/peripheral) to ask drivers to try the other route or what about applying for funding for a big interactive sign to ask drivers to use the other route (£5-10k) but not sure where it could be sited.

  • Engaging mapping / route-finding providers to stop showing Dumbreck Road as a Motorway connector (proposed by Steve Gray, GCC)

Steve Gray has responded it was a suggestion he had but he has never progressed.