Services: Traffic Circulation & Studies

picture of street signAs part of site development projects where there will be high demand to visit the site or where parking areas are proposed, it is necessary to ensure that traffic operation to and from the site, as well as, through the site is safe and efficient. In addition, it is also necessary to make sure that the traffic to and from the proposed development will not place a major burden on the roadways which will be used in traveling to and from the site. To ensure that traffic visiting a site will not have a major impact on a surrounding roadway network, many municipalities require that a traffic study be performed prior to approval.

The engineering staff of Arthur H. Howland & Associates, P.C. has experience in performing and presenting traffic studies and traffic circulation analyses for various types of site development projects. As part of every site development plan, our staff focuses a great deal of attention in developing parking and driveway layouts that function safely, efficiently, and aesthetically to make sure that visitors to your completed project will have a pleasurable experience.

Preliminary Data Collection

During the initial stages of a traffic study, it is necessary to collect traffic data for all roadways being analyzed as part of the study. This is typically done through visual observation, manual turning movement counts at intersections, and automatic traffic recorder counts at specific locations along a roadway. During the data collection stage of a traffic study, the traffic data is compiled to determine directional traffic volumes, travel speeds, and traffic patterns along the roadways where data was collected.

Traffic Analysis

Following the data collection stage of the traffic study, it is then necessary to utilize the collected data to analyze the collected traffic data to determine how well the roadway networks operate prior to any development. This background data and analysis serves as the reference point for the traffic study and the initial analysis of this data is known as the “Background” condition. This background data is then utilized to project traffic volumes based on an estimated growth percentage to the year when the proposed site development project is anticipated to open. This projected data and corresponding analysis is know as the projected “No-Build” condition and represents a conservative estimate of the background traffic volumes and traffic conditions in the year when the development is supposed to open. Lastly, the site generated traffic volumes are estimated using the Institute of Transportation Engineer’s (ITE) ”Trip Generation Manual” and/or previous experience with the certain type of development. Once the number of trips anticipated to be generated by the site are estimated, they are then assigned to the projected “No-Build” condition volumes for the road network surrounding the project. These volumes and corresponding analysis are often referred to as the projected “Build” condition and are compared to the projected “No-Build” and “Background” conditions to determine if the proposed site development project will cause a discernable impact to the road network which surrounds the project.

Results of Traffic Analysis

Analysis of the “Background”, projected “No-Build”, and projected “Build” traffic volumes is typically done through the use of computer modeling software such as Highway Capacity Software (HCS) that is based on the “Highway Capacity Manual” which is published by the Institute of Transportation Engineers (ITE). For analysis at intersections, traffic operation at critical approaches are assessed a letter value which corresponds to the approach Level of Service. Letter designations from A to F are used to represent the Levels of Service (LOS) for the traffic operation at an intersection or roadway with LOS A representing the best operating conditions with the least delay per vehicle and LOS F the worst with greater delay per vehicle. Level of Service is designated at unsignalized intersections by the average delay per vehicle.

Following the traffic analysis for a project, the results of analysis are organized an compiled into a Traffic Impact Study which is then submitted to all local and state regulatory agencies that have jurisdiction over the project. The Traffic Impact Study typically includes a narrative that outlines the methodologies, findings, and any recommendations made during the data collection, observation, and analysis phases of the traffic study. This Traffic Impact Study is then used by all regulatory agencies to determine whether or not the project will create undesirable traffic impacts and ultimately whether or not the project will be approved.

Strong Relationships and Collaborative Atmosphere

Arthur H. Howland & Associates, P.C. offers a wide array of traffic circulation and traffic analyses services. Over the years we have established strong ties with other transportation and traffic professionals offer consulting services for more specialized applications. In addition, we have built good working relationships with local public works and engineering departments, as well as, the State of Connecticut Department of Transportation in proposing site development projects that work from a traffic standpoint.

If you are involved a project that may require a traffic study or analyses, the engineering staff at Arthur H. Howland & Associates, P.C. can help. Contact us at (860) 354-9346 to discuss how we can help you with your traffic analysis needs.

> Go Back to Civil Engineering Services Page