How to Perform Route Analysis and Closest Facility in ArcGIS Network Analyst? A Complete Tutorial.

Introduction

This tutorial provides a comprehensive guide on performing route analysis and identifying the closest facility using ArcGIS Network Analyst. This analysis is particularly useful for urban planning, emergency response, and logistics, helping to optimize travel routes and facility locations based on real-world data.

Step 1: Compute Travel Time for Each Road Segment

To begin your analysis, you need to compute travel times for each road segment in your dataset.

• Gather your data: Download the required datasets from the following sources:

  • Network Data
  • Union County GIS Data
  • Block Group Shapefile

• Open ArcGIS: Launch ArcGIS and load the road network dataset.

• Calculate travel time:

  • Use the attribute table of the road segments.
  • Add a field for travel time.
  • Use the formula:

    Travel Time = Length / Speed
    

    Adjust the speed based on your context (e.g., average speed limits).

Step 2: Data Collection and Preparation

The next step involves preparing your data for analysis.

• Clean your data: Ensure there are no missing values or errors in your road dataset and other relevant layers.
• Format your data: Make sure all datasets are in compatible formats (e.g., shapefiles, feature classes).
• Create a network dataset:
  • Navigate to the "Network Analyst" toolbox.
  • Select "Create Network Dataset" and follow the wizard to include necessary attributes like length and travel time.

Step 3: Building the Network Dataset

With your data prepared, you can build the network dataset.

• Define the network:

  • Specify which road segments should be included.
  • Ensure that connectivity rules are correctly set.

• Add travel attributes: Include travel time and any other relevant metrics that will aid in your analysis.

• Validate: Once built, validate the network dataset to ensure accuracy and functionality.

Step 4: Performing Route Analysis

Now that the network dataset is ready, you can perform route analysis.

• Create a new Route Analysis layer:

  • Go to the "Network Analyst" toolbar, select "New Route".

• Add stops: Input the locations you want to analyze (e.g., starting point and destinations).

• Run the analysis:

  • Click the "Solve" button to generate the optimal route.
  • Review the results on the map, which display the best path considering travel time.

Step 5: Identifying the Closest Facility

After route analysis, the next task is to find the closest facilities to a given point.

• Create a Closest Facility layer:

  • Select "Closest Facility" from the Network Analyst toolbar.

• Add incidents and facilities:

  • Specify your starting points (incidents) and the facilities you want to analyze proximity to.

• Run the analysis:

  • Click "Solve" to find the closest facilities.
  • The results will show the nearest facilities along with travel times.

Conclusion

In this tutorial, you've learned how to perform route analysis and identify the closest facilities using ArcGIS Network Analyst. Key steps included computing travel times, preparing your data, building a network dataset, and executing both route and closest facility analyses.

For further exploration, consider diving into service area analysis or exploring other functionalities offered by ArcGIS Network Analyst to enhance your spatial decision-making capabilities.