Traffic calming request
Responsible for receiving and screening traffic calming requests (speed humps/circles/ round-abouts/ rumble strips etc.). Customer Care section arranges Traffic Engineering site inspections and general customer queries relating to Traffic Engineering. It plays an important role of liaising between internal departments and providing feedback to the client.
The contact person is: Esther Schmidt Pr Eng Operations Manager: Traffic Engineering and Analysis Tel: 011 298-5230 Fax: 011 298-5176. E-mail: email@example.com
Customer Care also handles high level (“VIP”) customers i.e. (Mayoral Office/City Manager/Section 80members/Councillors/ Regional Directors and Residence Associations).
Providing updated information regarding Capital Programmes/ depot maintenance programmes.
The CLO’s are available to set-up site inspections, assess proposals for project inceptions and attend Visible Service Delivery meeting as well as Integrated Development Programme meetings.
How do I request for Traffic Calming?
Requests for traffic calming can be made by registering a call with the City of Johannesburg call centre. Engineers will generally implement traffic calming (speed humps, raised pedestrian crossings and mini-circles) only if none of the following is applicable:
Not in front of entrances
Not in shade of trees and other physical objects during the day
Not where they are not illuminated by street lighting at night
Not on gradients in excess of 6 %
Not on gravel roads (cannot be painted and there is usually no street lighting)
Not on Class 4 or higher Class roads
Not on designated public transport routes
Not within a specified distance of other control mechanisms such as traffic signals
A structured analysis procedure enables the municipality to determine, as objectively as possible, whether it is appropriate to install traffic calming measures on a given street or in a given neighbourhood, and what types of measures should be used to achieve the desired objectives in terms of speed reduction and increased safety. The goal is to assess the problem and confirm that excessive speed is the issue. Traffic and speed studies are conducted. The analysis also look at accidents as well as the geometric characteristics of the road and its function (type of users, transit artery, bus route, residential local road, commercial street, etc.). A public consultation is included in the analysis and allows residents to express their thoughts and concerns.
What are some of the disadvantages associated with speed humps?
Speed humps are a major problem for emergency vehicles such as ambulances and fire engines. Apart from the major discomfort to ambulance passengers, they also delay response times substantially. This can be as much as 10 seconds per device. The longer wheel-base, stiff suspension, high vehicle weight, as well as the sensitive equipment and injured victims transported by these vehicles, requires drivers to slow almost to a stop to negotiate the devices safely.
Speed humps are a very blunt instrument. In fact, different vehicles respond very differently with heavy vehicles such as HGVs, buses and other public service vehicles being particularly prone to discomfort unless humps are traversed at very low speeds. It is simply impossible to design a speed hump that is negotiable comfortably at a reasonable speed by all vehicles and which is not painful to the occupants. Depending upon the vehicle and the hump design, going over a hump at a higher speed may cause less discomfort than a lower speed.
Speed humps cause atmospheric pollution from the speeding up and slowing down of traffic between the humps (see TRL report No. 482 on this subject). For example, TRL reports a 59% increase in CO, about 50% increase in HC and about 25% in CO2 from petrol catalyst vehicles averaged over all types of traffic calming measures, with even higher numbers over more “severe” measures such as speed humps.
Speed bumps can create additional traffic noise, although this tends to depend on the type of vehicle. HGVs and other goods vehicles would typically generate substantially more noise than before, while cars will generate less noise, although the variability of the noise level as vehicles slow down before bumps and accelerate afterwards can mean that the noise is more noticeable than before.
Speed humps can result in the relocation of the problem to adjacent streets especially in areas where the road network is designed in a grid pattern.