Understanding Why Transport Planners Carry Out Traffic Surveys

Traffic surveys are utilised for many purposes. These include being part of the process that resolves national, regional and local traffic issues. Often, the data gathered plays a critical role in the decision making process in highways planning. Sometimes this contributes to projects related to the planning, construction and maintenance of highway infrastructure. With major investment in short supply, traffic survey reports can influence investment in future infrastructure as well as making the best of our current road networks. On a local level, surveys are also utilised for smaller projects that may deal with parking issues or the effectiveness of traffic calming measures in regards to road safety issues.

With big development projects, it would require much bigger studies. This may require turning counts at a number of junctions, vehicle speed surveys, pedestrian desire line surveys, vehicle queue surveys and even observing how often pedestrians cross at a crossing and the affect that may have on vehicle flow. In some instances, particularly where there may be some new road building (such as a bypass) origin and destination surveys may be required across the study area, which typically can be carried out using number plate surveys at all entry and exit points to the study area as well as within the study area at major intersections in order to track individual car movements. On a smaller schemes, traffic surveys may only be required to determine vehicle 85th percentile speeds and two-way link (road) counts. This would help determine such issues as visibility splays and highway capacity and whether the development proposals would have an adverse affect on the highway.

A recent requirement for many development proposals is to develop Travel Plans for the development end user. The basis of the Travel Plan is to survey of staff/residents, looking at their travel characteristics and their willingness to change if they are given various incentives. The Travel Plan survey can either be carried out manually (face to face) or on-line as staff log in to their workplace computers. The survey would need to be carried out at the inception of the Travel Plan and then either annually or every two or three years in order to track any changes, to identify if targets are met or indicate areas where further work/incentives may be needed.

For more information about UK Traffic Surveys please go to the website at Modal Group.