Preparing the Data

The following Skill Drills for preparing the data use the knowledge you have learned in previous courses, including Geospatial Concepts (GSP 101) and Geographic Information Science (GSP 270). Therefore, the instructions do not contain many step-by-step details. You should refer to previous coursework if needed. Registered students may also post questions on the weekly Q&A Discussion Forum on the Canvas LMS.

Skill Drill: Acquire GIS data from the Humboldt County Website

To create a network dataset, you will need a roads layer. In previous courses, you learned how to acquire data from public sources. Here you will download a shapefile containing the roads for Humboldt County.

Currently, there are multiple roads layers on the website. You want the one that says Humboldt County GIS Roadway Centerline.

Navigate to the Humboldt County website. Locate a shapefile containing the roads data and download the file. Decompress the file in your original folder and check the spatial reference system. If necessary, use the Project tool to create a copy of the data with the NAD 83 UTM Zone 10 spatial reference system.

An image of the project tool used on the Humboldt County Roads layer.
The Project tool never alters the original data. It creates a copy of the data with a new spatial reference system.

In ArcMap, open a new blank map document add the layer with the correct spatial reference to your Table of Contents. This layer will define the spatial reference for the dataframe window if it is the first layer loaded into the table of contents.

An image of the projected roads layer added to the table of contents.
In ArcMap, the dataframe window adopts the spatial reference from the first layer loaded into the Table of Contents.