State Officials Turn to Crowdsourcing for Stone Wall Mapping Effort

Jan 21, 2019

https://nhgranit.maps.arcgis.com/apps/webappviewer/index.html?id=ec12d9d5583c4709be446a77115bf0a2

The New Hampshire Department of Environmental Services has launched a new online crowdsourcing project with the goal of mapping every stone wall in the state.

The project is built around an online LiDAR map. 

LiDAR is similar to radar or sonar, except it relies on lasers. Geologists often turn to LiDAR surveys because they produces accurate renderings of the topology beneath the tree cover.

LiDAR reveals hills, rivers, ravines, and, as it turns out, stone walls.

But there are more stone walls revealed in the LiDAR scans of New Hampshire than any one researcher or historian could hope to map. So DES is inviting you to help record the locations of the state's stone walls by looking through the online map for the telltale straight lines that cut across the otherwise curvy landscape.

New Hampshire state geologist Rick Chormann says the project's goals are manyfold: to teach people about LiDAR, to get them thinking about the ground beneath us, and of course, to help preserve the state’s long history of building stone walls.

"You know, there’s no guarantee that these walls are going to exist in the future and so I think it’s important to record their existence, as best we can, today," said Chormann. "They’re emblematic of our landscape of the identity of the state of New Hampshire. And I think we would lose a part of who were are if we let them just be erased."

Already, users have mapped hundreds of miles of stone wall since the website went public last Tuesday.