How Traffic Impact Studies Support Sustainable City Design

Bottom line: A traffic impact study translates a proposed project into measurable effects on trips, intersections, queues, multimodal access, safety, and road operations.

• For public works teams: A TIS reviews existing traffic, expected trips, lane needs, signal timing, pedestrian and bicycle movement, transit effects, and mitigation options.
• For city leaders: The study helps explain how a project will affect residents, commuters, adjacent neighborhoods, and long-term street function.
• What to watch: Peak-hour trips, detour routes, school traffic, pedestrian crossings, and nearby development can all change the recommendations.
• F&V perspective: Fleis & VandenBrink provides traffic engineering studies that help municipalities and project teams make data-based transportation decisions.

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Any type of construction project can potentially disrupt traffic patterns in its surrounding areas, even if the project itself isn’t close to the roadway. This, in turn, challenges municipal planners and managers to find better ways to keep their community’s overall design sustainable and usable for everyone living there.

Starting development projects with a traffic impact study (TIS) is one of the best ways to keep community designs sustainable. Let’s explore the connection between these studies and how they can help urban areas stay sustainable during construction.

Traffic Impact Studies: The Basics

Traffic impact studies, sometimes called traffic impact analyses, are an important part of development and maintenance projects of all types. They are essential for assessing the possible effects of a project on the surrounding roadways.

During a traffic impact study, your traffic engineer will estimate the additional traffic the proposed project will cause. They will also identify potential problems that might affect the traffic flow around the project and suggest options for mitigating negative impacts in the area.

They’re often necessary for projects on public and private property alike, including the redevelopment of existing properties.

When Your Project May Require a Traffic Impact Analysis

Local and state-level guidelines and requirements for traffic impact studies can vary from place to place. However, according to the Institute of Transportation Engineers, municipal governments typically require traffic impact studies when new developments are expected to generate 100 or more new trips during peak hours. There are also some variations for different land use types, including public, private, residential, and commercial purposes.

Some lower-impact projects may only require a summary or traffic statement. However, when you work with a firm that specializes in traffic engineering, they can tell you what your project will require based on the area’s traffic conditions.

These are some of the most common use cases requiring traffic impact studies.

Projects Generating New or Large Traffic Patterns

If your project has the potential to shift traffic patterns into different areas, it can be helpful to conduct a traffic impact study in the area. This can help your project team, city planners, and local departments of transportation better understand the potential implications of everything from commute times to vehicle emissions and address the effects of the shifting traffic pattern before they become problematic.

Projects That Impact Existing Road Networks

The requirements for traffic impact studies can vary depending on the type of project. However, if your project is close enough to public roadways and expected to increase the number of trips in those areas, your project may need a traffic impact study.

Traffic engineers will generally verify the existing traffic conditions on existing roadways, along with anticipated traffic conditions with or without your development. They will also look for any possibility of substantial changes or impacts on public transportation and other multimodal transportation systems. This allows you to fully understand how your project will impact residents, commuters, and other stakeholders who use the streets and roads around it.

How Traffic Impact Studies Support Sustainable Urban Design

Reduces Unnecessary Emissions

Whether it’s the redevelopment of private property or a large-scale project that could potentially shut down heavily used roads like interstates or other highways, construction projects can cause an increase in vehicular emissions. Even partial lane closures can significantly increase fossil fuel emissions by slowing down traffic and keeping cars on the road longer, making air quality around the site worse.

As part of your local government’s commitment to sustainability in urban development, it’s essential to make sustainable design and construction decisions a priority. Using the findings from a traffic impact study allows your stakeholders, project managers, and urban planning officials to make the air and water in your city cleaner for everyone living there.

Requires Less Frequent Road Repairs

Without proper planning, shifts in traffic patterns for construction can also make frequent road repairs more likely.

For example, if a high-traffic main road is undergoing maintenance or repaving, it may cause the same volume of cars to be diverted onto adjacent, lesser-used roads. Because these normally quiet roads are designed for lower volume traffic, using them as a detour during construction can cause these side streets to develop cracks and potholes, deteriorating more quickly.

This can ultimately cost the city or county (and their taxpayers) more to maintain the roads.

However, using the results of a traffic impact study as a guide can help project stakeholders better understand how to direct the flow of traffic in ways that ease the impact on low-traffic roads. This allows roads to more easily handle shifting traffic patterns during the project.

Causes Fewer Disruptions to Citizens

Urban safety development goes hand in hand with sustainable city planning. No development project exists in a vacuum, making traffic impact studies essential for understanding how the project will affect nearby neighborhoods.

Whether it’s motorists, cyclists, pedestrians, or just residents and workers in buildings adjacent to potential construction sites, construction projects can be a major disruption to daily life in urban areas.

Following the recommendations from a traffic impact study helps to reduce the burden on commuters in the area around the project. This can reduce the burden of traffic congestion during peak hours and, most importantly, increase traffic safety by minimizing the factors that lead to traffic accidents.

Work with F&V On Your Next Traffic Engineering Project

At Fleis & VandenBrink, we work with municipalities and private business owners across Michigan and Indiana to help them make informed decisions about their projects based on traffic impact studies.

Reach out to us today to learn more about our traffic impact study services for public, private, and mixed-ownership projects.