What are the most effective tools and methods for conducting traffic impact studies for land development?

1 Define the study area and scope

The first step in conducting a traffic impact study is to define the study area and scope, based on the location, size, type, and intensity of the proposed development. The study area should include the site access points, the adjacent road network, and the relevant intersections and segments that may be affected by the development. The scope should specify the objectives, assumptions, data sources, analysis methods, and performance measures of the study.

2 Collect and analyze existing data

The next step is to collect and analyze the existing data on the study area, such as traffic counts, speeds, volumes, turning movements, signal timings, crash records, geometric features, and land use patterns. This data helps establish the existing conditions and baseline scenarios for the study. The data should be collected during typical peak hours and normal days, and adjusted for seasonal and growth factors if necessary.

3 Forecast future traffic demand

The third step is to forecast the future traffic demand for the study area, considering the proposed development and other planned or committed developments in the vicinity. The future traffic demand can be estimated using various methods, such as trip generation, trip distribution, mode choice, and trip assignment. These methods use factors such as land use type, floor area, population, employment, trip rates, trip lengths, modal splits, and network characteristics to predict the number, origin, destination, mode, and route of trips.

4 Evaluate traffic impacts and level of service

The fourth step is to evaluate the traffic impacts and level of service (LOS) for the study area, using the existing and future traffic data. LOS is a qualitative measure of traffic operations, ranging from A (free flow) to F (congested), based on criteria such as delay, speed, density, and queue length. The traffic impacts and LOS can be evaluated using various tools, such as traffic simulation models, capacity analysis software, or manual calculations.

5 Identify and test mitigation measures

The fifth step is to identify and test the mitigation measures that can reduce or eliminate the negative traffic impacts of the proposed development. The mitigation measures can include physical improvements, such as adding lanes, signals, roundabouts, or sidewalks, or operational improvements, such as adjusting signal timings, restricting turns, or implementing parking management. The mitigation measures should be tested using the same tools and methods as in the previous step, to compare their effectiveness and feasibility.

6 Prepare and present the report

The final step is to prepare and present the report that summarizes the findings and recommendations of the traffic impact study. The report should include the following sections: introduction, study area and scope, existing conditions, future conditions, traffic impacts and LOS, mitigation measures, and conclusions. The report should also include supporting data, such as maps, charts, tables, and appendices. The report should be clear, concise, and consistent, and follow the relevant standards and guidelines.

7 Here’s what else to consider

This is a space to share examples, stories, or insights that don’t fit into any of the previous sections. What else would you like to add?