free data

free data

In our last  blog post we talked about 33 feature classes you can map in your community without using a GPS. A key element for mapping new data is that you must have a base map (including aerial photography) to serve as a backdrop for your municipal GIS. If your Pennsylvania community hasn’t yet developed a base map, now is the time to start with some easily obtained (and free) data from Pennsylvania Spatial Data Access (PASDA). PASDA is the definitive source for open source geospatial data in Pennsylvania. PASDA in a one-stop data portal that aggregates data from 63 data providers including: local, county, state and federal governments, educational institutions, and non-profit organizations.   The data sets from PennDOT, PA DEP, PA DOH, and PA DCNR are updated regularly. If you haven’t visited, you definitely should take a look to explore the depth and breadth of the information available.

A very useful feature of the PASDA website is the Pennsylvania Imagery Navigator ( ).   The Imagery Navigator allows you to zoom to any part of the state and download all of the imagery for that location. The imagery published through this search interface includes: USGS quadrangle maps, digital elevation models, LiDAR point clouds, contours and breaklines, USDA annual imagery, PAMAP orthophotography, as well as selected regional and county orthophotography.

Simple Base Map Demonstration

Using the “Data Shortcuts” menu on the right side of the PASDA home page, you can acquire the data to assemble a very serviceable base map. To prove this point, starting from scratch, we assembled a simple base map that shows the following data: state and local roads, county and municipal boundaries, railroads, public lands (parks, forests, game lands), waterways, flood hazard areas, 2015 aerial photography, wetlands, soils, and elevation contours. It took us about 90 minutes to download all of the data and compile it into an ArcGIS map. The result of the project is shown in the following four screen shots.

Of special interest to municipalities just starting on the geospatial journey, the last map includes road edges derived from PAMAP LiDAR data. Our next blog post will demonstrate how you can complete that process on your own.





More About PASDA


Pennsylvania Spatial Data Access (PASDA) is Pennsylvania’s official public access geospatial information clearinghouse. PASDA was developed in 1996 by the Pennsylvania State University.

PASDA is a cooperative project of the Governor’s Office of Administration,  Office for Information Technology, and  Penn State Institutes of Energy and the Environment  of the  Pennsylvania State University. Funding and support is provided by the Pennsylvania Office for Information Technology. Penn State contributions include system administration support and infrastructure from the  Institute for CyberScience, and the  College of Earth and Mineral Sciences.

PASDA was developed as a service to the citizens of the Commonwealth of Pennsylvania. The purpose of PASDA is to serve as the Commonwealth’s comprehensive and coordinated open geospatial data portal that provides free public access to geospatial data and information by, for, and about the Commonwealth of Pennsylvania. PASDA is Pennsylvania’s node on the National Spatial Data Infrastructure, Geospatial One-Stop, and is integrated with the National States Geographic Information Council GIS Inventory.

free data