If ANPR is the solution, what is the problem?

Published by Chris on

Oxfordshire County Council have recently received the necessary legislative powers to use Automated Number Plate Recognition (ANPR) cameras for traffic enforcement measures that are not bus gates (there has been ANPR on bus gates in Oxford for years).  

The new ANPR powers could be a significant traffic management tool for the future, if wielded with precision, but could also prove damaging, if used bluntly to achieve political compromise over a contentious issue such as LTNs.  

There is a need to think carefully about ANPR as the ‘next layer’ of the Cowley LTNs, and take cues from London solutions, where ANPR and LTNs have been mixed for years.  There is a risk that ANPR changes are seen as ‘tweaks’, and that the effect on the core premise and operational success of an LTN (low traffic, all of the time, creating protected active travel routes and making short journeys by car less attractive) is therefore compromised by ill considered changes.

Compromise means ANPR exemptions, and ANPR exemptions could quickly mean medium-traffic neighbourhoods.

So why do the LTNs need to be compromised?  To maintain political popularity?  The Cowley LTNs and their council supporters have already survived two back-to-back local elections, when the schemes had just been implemented and shock-of-the-new was at it’s highest.  LTN haters will keep hating LTNs, even if they are compromised.  Can you ever really pacify people who are setting fire to bollards?  

This article explores the potential use of ANPR in Cowley’s three LTNs.

How could ANPR be used in Cowley’s Low Traffic Neighbourhoods?

ANPR cameras allow for some motor traffic to pass through, either all day, or at certain times of the day.  ANPR cameras could be permanently fixed (on poles, at specific sites), or mobile (used from a vehicle).  

Fixed ANPR cameras are already used in Oxford for bus gate filters. Mobile ANPR cameras can be used to enforce other types of traffic restrictions (e.g. one-way streets). 

ANPR use in LTNs can:

  • help to prioritise bus traffic
  • reduce the issue of motorcycles frequently violating the traffic restrictions (although this is expected to reduce over time as food delivery drivers increasingly shift to eBikes)
  • improve the perception of emergency service access
  • exempt specific traffic types to facilitate easier access

However, there is a risk that ANPR use could easily lead to a ‘leaky’ LTN, whereby over time exemptions are granted to a critical mass of motor vehicles, which changes the traffic volumes within an LTN from low, to medium. 

Leaky LTNs reduce the opportunity for modal shift, which we know relies on a ‘snowball’ effect to really take off.  Modal shift starts with the low-traffic active travel routes created by the LTNs, and by making short journeys less attractive to drivers.  If those routes are diluted and become medium-traffic due to ANPR exemptions, then modal shift is less likely to be triggered.  This is especially true of primary school age children, and their school run.  If roads remain hostile for Active Travel in the early school years, that’s a whole load of journeys which need to continue by car.  Crucially, if children are not able to cycle to school from the start (i.e. Reception year), it is much harder to get them cycling when they are older.

Other considerations:

  1. Where filters are changed from closed (i.e. with a bollard), to enforced (i.e. open but with ANPR) there is a risk of more serious traffic violations, by way of concealed or fake number plates, to avoid the subsequent penalty, or simply accepting the penalty charge.  It only requires a handful of drivers every day to speed through ANPR filters to greatly reduce the sense of safety, stop parents from letting kids play out etc, i.e. the cost to the community is immense. 
  2. Mobile ANPR could be a significant deterrent to motorcycle violations, while allowing for filters to retain a permanent traffic restriction (a bollard, or planter).
  3. If some filters are to be ANPR controlled, then other filters within an LTN could be upgraded to permanent, fixed bollards, in order to reduce the on-going vandalism issue.
  4. ANPR cameras may be subjected to vandalism.  Due to the cost implications of repairing/replacing, it would be expected that Oxfordshire County Council and Thames Valley Police would show greater willingness to implement preventative measures and to prosecute criminal damage of ANPR equipment.
  5. Rising bollards may be considered a viable infrastructure solution to restrict filter access either via access code/card, or automatic timing.
  6. Generally, the greater the complexity of ANPR exemptions, the greater the cost of administration, and the greater the use of ANPR, the greater the internal cost of managing appeals etc.

Potential ANPR Exemptions in LTNs

Please note that the table below assumes that an LTN could have two kinds of ANPR: those on bus routes (such as are already in place on Bartholomew Road and Cornwallis Road), and those not on bus routes. 

ANPR Exemption TypeBus gate filter exemption?Non-bus gate filter exemption?
Emergency ServicesYes
‘Pick Me Up’ buses (not currently running)Yes (provided they are small, electric, and stick to 15mph inside LTN areas)
Taxis (Hackney Carriage and Private Hire ‘minicabs’)YesNo, Active Travel routes will get compromised by cut-through taxis.  Unlike buses, taxis are not tracked centrally and do not reliably adhere to speed limits.
Blue Badge holdersNo, the primary motivation for LTNs is to minimise road danger, and blue badge drivers create just as much danger to vulnerable road users as other drivers do.Blue Badges are primarily about parking and short walks from the parking spot to the final destination. They are not, and never were, about getting from A to B in the shortest possible time.  As with all drivers Blue Badge holders need access (which is maintained in all LTNs), but they do not need journey time savings. An exception must be made in limited cases for SEN transport where there is a statutory time limit on journeys and this would need to be carefully assessed.Blue Badge holders would receive exemption to travel through the main road city-wide bus gates, proposed to be implemented as part of the Central Oxfordshire Transport Plan (COTP).
Local businesses ResidentsCarers/nurses etcFuneral CarsNo, would produce a medium traffic neighbourhood, undermines incentivisation of modal shift, is hard to administer, could create division and/or envy (e.g. ‘gated communities’) between those that can travel through one filter but not another.
Electric vehiclesNo, would produce a medium traffic neighbourhood, and eventually a high-traffic neighbourhood.
Timed exemption (e.g. before 7am and after 7pm)No, this may protect the route for school run Active Travel, but what about after-school clubs, Cubs/Guides, summer evenings at the park, shift worker commuting and residents’ sleep disturbance?  And what does it gain in terms of facilitating motor traffic use outside of those hours, when the main roads are normally uncongested?Any traffic filter that allows traffic through after a specific time will become an attractive cut-through route outside of the exempted hours, and as traffic is generally lighter at those times anyway, there is a risk of increased speeding through side roads that are normally very quiet during the day.  The inconsistency of road use in that scenario could lead to increased road danger.Timed traffic filters also prevent more permanent public realm improvements to be made, as the road will need to cater for both high active traffic volumes, and high motor traffic volumes, essentially compromising the road use for both groups.  Examples of fixed public realm improvement made possible by permanent traffic filtering include lighting, widened footpaths, new street furniture e.g. seating, bins, noticeboards, public art installation, parklets, and play spaces.

Where could ANPR be used in each of the Cowley LTNs?

Temple Cowley LTN

  • The LTN primarily serves to reduce cut-through traffic between Oxford Road and Hollow Way, i.e. avoiding the ‘Swan’ junction
  • As such there is no community benefit to allowing taxis through the LTN, this would simply be a short-cut
  • There are no current or planned bus routes that travel through this LTN
  • Lack of enforcement means the LTN is compromised by motorcycle (primarily food delivery) traffic
  • Introduction of fixed ANPR would be likely to limit future public realm improvement in this LTN

Church Cowley LTN

  • There is a current bus route through this LTN, using an ANPR-controlled bus gate.  This route could be re-routed to more directly serve the Cowley Centre shopping area, including provision of a new bus stop on Crowell Road
  • There is a community benefit in allowing buses and taxis to travel more directly between Littlmore and the Cowley Centre shopping area, and vice versa
  • Lack of enforcement means a key active travel corridor (Beauchamp Lane)  is compromised by motorcycle (primarily food delivery) traffic, which may worsen if the Littlemore Road traffic filter is to be ANPR controlled
  • The western ‘half’ of the Church Cowley LTN has a single entry/access road.  ANPR installation at the Mayfair Road filter could be perceived to provide more direct EMS access.  This should be resisted, as the bollard at this filter is collapsible, and in practice EMS crews are not consistently aware of the bollard types at every filter, and generally prefer to re-route.

Florence Park LTN

  • There is a current bus route through this LTN, using an ANPR-controlled bus gate
  • Lack of enforcement means a key active travel corridor (Rymers Lane)  is compromised by motorcycle (primarily food delivery) traffic
  • Introduction of further fixed ANPR would be likely to limit future public realm improvement in this LTN


  • As soon as there is a potential for a critical mass of ANPR exemptions (i.e. buses, taxis and blue badge holders), or if timed filters are preferred, then the route can no longer be considered a key active travel route, and would require implementation of protected cycle lanes in order to maintain safety
  • Across the three Cowley LTNs, the Littlemore Road traffic filter is the only obvious candidate for conversion to ANPR controlled filter, and this would be to facilitate revision of a bus route to use Crowell Road, and improve public transport connections between Cowley and Littlemore.  I.e. in effect this would represent a movement of the Church Cowley LTN bus gate from Bartholomew Road to Littlemore Road
  • Do not provide Blue Badge exemptions for side-road bus gates within the LTNs, but do exempt Blue badge holders for main-road bus gates outside of the LTNs
  • If Blue Badge holders are to remain unexempted, and emergency service access remains possible via collapsible bollards and re-routing, there is no compelling case to implement ANPR at any of the other existing Cowley LTN traffic filters
  • Accelerate Active Travel activation schemes and public realm improvements to show value to all residents
Categories: Traffic