US National and International Map and Imagery Data
Over the years, ESC has compliled a list of "go to" sources for free and/or open source map and imagery data for use in our GIS and CAD packages. The following is a list of some of the sites that we use often use. Some of the available data are in great detail, while others are more general in nature. However, both are useful through various stages of project implementation.
We also recognize that for many projects higher resolution data, or more recent data, are required beyond what can be found in an open environment. In that regard, we give a link at the end of the list to a good resource for getting started with purchasing proprietary imagery. Where those circumstances arise, we typically assist our clients in the decision making and purchasing processes.
The list of sites on this page will change, and probably grow, through time. As we add sites, we will try to annotate the listings as we go.
A Definitive Guide to Buying and Using Satellite Imagery: All of the sites below point to sources of freely available data. If you need something beyond that, this article might give you some starting points for purchasing high resolution data, or having custom data acquired to suit your particular needs. Even if you don't have needs beyond free data, the article is well worth reading.
USGS - The National Map: If you are looking for basemap data, this is the site for you. The National Map is a great source for basic infrastructure, essential topographic data, USGS topo maps and basemap-scale images. The site falls short on detailed data, but that was never a priority. Overall, it's a good place to start when looking at a new area.
USGS - Earth Explorer: What the National Map lacks in detail and depth of data, the Earth Explorer site more than makes up for. On Earth Explorer, you can meter-scale imagery, detailed topography, LandSat and Sentinal imagery and much more. For those of you who are interested in international locations, the Earth Explorer Landsat, Sentinal and SRTM (Shuttle Radar Topography Mission) holdings are global. Note: you will need to become a registered user to take full advantage of Earth Explorer, but it is free and painless. So, sign up!
NOAA - Office of Coast Survey: The NOAA OCS site is a source of navigation charts for coastal United States. The charts are available at a variety of levels, including quite detailed views. Charts can be downloaded for free in PDF or GIS formats.
NOAA - National Geodetic Survey: The NGS site is a souce of a variety of data types associated with geolocation and imagery. Of particular note is that the site offers a database of locational markers, including benchmarks. Marker and benchmark data can be downloaded in either tabular or GIS format.
US Army Corps of Engineers - Hydrographic Surveys: If you need detailed data for ship channels in the coastal US, this is the site for you. For the generalist, channel bathymetry can be downloaded in PDF format. Hard data can also be downloaded in ASCII format for loading into your favorite GIS mapping or CAD package.
Open Nautical Charts - Global Navigation Charts: A global quick-look map viewing interface for basic nautical navigation charts. Level of detail varies by region.
Global Ship Traffic - ShipTraffic.net: Global navigation charts and near real-time locations of ship-going vessels. Clicking on individual ship icons displays information about the vessel.
US Census Bureau - TIGER Shapefiles: As the host name implies, TIGER data were developed for use in conjunction with the US census. The shapefiles contain a variety of polygon, line and point data types that represent geographic and political boundaries, transportation elements (rails and roads down to the local level) and significant places as points. These datasets are updated on a regular basis and can be expected to contain significantly more current cultural elements than are depicted on most 1:24,000 scale USGS topographic quadrangles.
OpenStreetMaps - OSM Downloads: OpenStreetMaps is like TIGER on steroids. It is particularly good with transportation infrastructure, and includes elements (mostly) found in TIGER (but no census tracts, etc.). There are several things to consider about this database. First, OSM comes in a GIS friendly format. Second, OSM is a global database, but for obvious reasons it is more detailed for some parts of the planet that for other parts. Third, it includes lots of very detailed elements, like some building outlines. In other words, for basemap vector and point data, it is just about as good as it gets... FOR FREE. One bit of caution is that subsequent to downloading it is generally necessary to subset the data valume through queries to create individual files for specific data types. Also, in the initial OSM selection page (map based), it is fairly easy to exceed the allowable download size, but this is remedied through listed alternative download sites.
US Department Transportation - Transportation Statistics Portal: The BTS National Transportation Atlas Database provides a wealth of data related to national trasportation infrastructure. It is well thought out in terms of organization, where major categories of data are arranged intuitively (marine, rail, roads, etc.). Data found here are useful for basemap-level map construction.
US Department of Homeland Security – Homeland Infrastructure Foundation-Level Data: The HIFLD web site hosts an enormous amout of GIS friendly data. The "Open Data" part of this site provides links to energy, transportation, environmental, mining, demographics, etc. data that are available to the general public, although with proper credentials and an account, restricted access datasets are available as well. For convenience, the HIFLD provides an Excel spreadsheet of all of the data holdings available through the site.
US Department of Agriculture – Web Soil Survey and Soil Data Access: Between these two Department of Agriculture sites, you can get a really good synopsis for soil types and characteristics for pretty much any place in the US. Both GIS friendly, mappable data and tabular data are available through the sites. Of particular interest is that a fair amount of engineering pertinent soil properties can be gleaned from "Soil Data Access".
Perry-Castaneda Library Map Collection – University of Texas at Austin: The Perry-Castaneda site has been around for MANY years and offers a wealth of maps for pretty much every corner of the globe, in bitmap formats.
Mad Mappers: Yes, you read that correctly. Aside from having a really COOL NAME, the Mad Mappers site is where you can find vintage, georeferenced bitmaps of Russian topographic maps for Africa. Some of the maps are FREE, others are not. Yes, the annotations and names are in Cyrillic, but NUMBERS are the same as English, so contour levels are readable. Regardless, it represents an awesome effort to compile little known (and underused) maps from the African continent.
Maps | U.S. Energy Atlas (eia.gov): The U.S. Energy Information Administration has a neat collection of maps called US Energy Atlas which is to be used for its comprehensive references for data and as interactive maps of energy infrastructure and resources of the United States. It even has a map for natural disaster disruptions.
Energy Specialists Consulting is a Texas-based company. We would be remiss in not pointing to sites for Texas mapping and imagery data. Yes?
Texas
Hang on... We're getting there... We promise, you won't be disappointed. It's easy to insert a name and a link, it does take a bit of thought to annotate the entries.