TopoView app preview of Detroit, Mich.
The U.S. Geological Survey (USGS) is changing the way people access its trove of historic maps.
The federal agency’s new topoView app allows anyone to access and download topographic maps — nearly 180,000 of them — dating back to the 1880s.
An internal business tool turned public resource, topoView makes searching for maps more intuitive. And it’s free.
Click, zoom or type your way to a location. Select a scale, determine a date range and you’re set — all the topographic maps you’ll need.
A welcome update, topoView replaces the maze of clicks that once thwarted public access to historic maps.
That system even slowed USGS scientists, like Chris Garrity, who used it to find and download maps for government projects.
Frustrated by the cumbersome interface, Garrity threw on his developer-hat and got to work building the new app to help with future projects.
He started with a prototype and then tracked how people were using it.
“We found two sets of users,” Garrity said. “The average user wanted a map of their hometown and others wanted something more specific.”
For something more specific, the tool’s tailor-made for projects that span long periods of time, he said.
From coastal development to urban-sprawl (see below), topoView offers a comprehensive view of Great Lakes history, through what Garrity calls “a living, breathing collection.”
TopoView will grow with user feedback, he said. “Maps are added and updated constantly.”
The collection has ballooned into over 1 million files, including five different file types based on user input.
In addition a regular image format, JPEG, topoView offers GeoTIFF for geographic information scientists, like Garrity, and KMZ for Google Earth users.
Here’s how Echo used topoView to show urban development in Milwaukee:
