There’s a faint scar running across Bellingham Bay, and the landscape between Acme and Kendall looks like a river ran through it.
Those are some of the Earth’s secrets that can be found on a new interactive map produced by the state.
Using lidar technology, the Washington State Department of Natural Resources has mapped a good third of the state, revealing the smallest of details hidden beneath trees, buildings and other obstructions.
DNR’s goal was to map landslides, for example, the impact of the Van Zandt “dike” on the Nooksack River. An aerial photo of the South Fork Valley shows the Nooksack River meandering through lowlands. Stripped of trees and surface greenery, the lidar image of the same area shows a massive landslide that constricts flow of the river to the west side of the valley.
Whatcom County’s unique geography – from the flat, fertile berry fields around Lynden to the craggy peaks that dominate the eastern foothills and beyond – is amplified by the map.
How to use the map
The map can be found at fortress.wa.gov/dnr/protectiongis/geology/?Theme=wigm
Hit the “Clear All” button and then scroll down and click on the “Lidar Hillshade” box and one or both of the boxes below it. To better get your bearings, go to Base Layers and choose Street Map.
Toggling between “Bare Earth” and “Top Surface” is one of the best ways to view the map.
In Top Surface view, buildings and trees become visible. The detail is so precise, individual trees can be seen.
Bare Earth – when all those distractions are removed – is the most revealing. Road beds, volcanic flows, gulches, glaciers and slopes of every kind can be seen. The detail goes beyond what you’ll find on most topographic maps.
What you’ll find
Look at Sehome Arboretum in Bare Earth mode and you’ll see a series of grooves carved by ancient glaciers etched into the hillside. In Top Surface Mode, you’ll see the dense forest of the arboretum.
Under Base Layers, switch to “Bathymetry” and the vast underworld of the Salish Sea becomes visible. There’s a faint scar across Bellingham Bay where the Nooksack River delta empties, and you’ll find deep dropoffs around Lummi Island and the San Juans.
The map also provides some ready-made detail in the “Map Theme” menu at upper left. You can see tsunami evacuation routes, former coal mines (hint: most of Bellingham), and existing water wells (click on “Subsurface Geology Information System”).
Washington state is not lacking in spectacular geology and geography. The two come together in stunning detail around Mount St. Helens.
The blowout from the volcano’s 1980 eruption can be seen in detail, while on the south side, ancient volcanic flows look like they oozed yesterday.
How it works
Lidar (light detection and ranging) uses lasers mounted on aircraft to visually cut through foliage and take precise measurements.
The technology is so efficient that it has led to major discoveries in archeology. For example, scientists studying lidar maps have found lost cities in Central America and Asia that are hidden by jungle vegetation.
Craig Sailor of The News Tribune in Tacoma contributed to this report.