By Colin Bowyer, Communications Manager - April 24, 2025
The increasing frequency of climate-change induced wildfires in Oregon threaten heritage sites throughout the state. In 2020, Oregon saw devastating wildfires that destroyed historical structures at Jawbone Flats in the Opal Creek Wilderness and at Breitenbush Hot Springs. Around 125 acres in Silver Falls State Park, outside of Salem, also burned during those fires; however, fortunately, no historic structures were damaged in the park.
Starting in 2024, researchers from the School of Communication partnered with the Geomatics Research Group in the College of Engineering to help preserve the legacy of historic structures inside Silver Falls State Park. Supported by a grant from the Oregon Heritage State Historic Preservation Office, the multidisciplinary team, led by Senior Instructor of New Media Communications Todd Kesterson and geomatics professors Michael Olsen and Ezra Che, used three-dimensional scanning to produce digital replicas of three of the park’s historical structures: the South Falls Lodge, the South Falls Nature Store, and the Stone Kitchen Shelter.
Blueprint of South Falls Nature Store | Credit: Oregon State Archives
Roof of South Falls Lodge
A brief history of Silver Falls State Park
Silver Falls State Park is the largest state park in Oregon, containing over 9,000 acres of trails, waterfalls, campgrounds, shelters, and more. The area was settled originally by the Kalapuyan Indians, who were removed through various treaties and resettled on the Grand Ronde Reservation in Yamhill County. In July 1933, Silver Falls was officially dedicated as a state park and in 1935 the Civilian Conservation Corps began to build trails and park structures inside the park’s limits. The park’s main concession building, the South Falls Lodge, opened in 1938. The Stone Kitchen Shelter dates back to 1936.
Using a Leica scanner on the exterior of the South Falls Lodge
Using a Leica scanner for the inside of the South Falls Lodge
Setting up the drone to capture aerial imagery
3D scanning process
On April 24, 2024, OSU researchers used state of the art reality capture tools to create detailed three-dimensional digital models of the South Falls Lodge, the South Falls Nature Store, and the Stone Kitchen Shelter. The process involved two types of technology: photogrammetry and laser scanning. Photogrammetry uses a camera to take successive images of an object, and then uses structure-from-motion (SfM) software to stitch those photos together to build a three-dimensional digital replica. Laser scanning uses Light Detection and Ranging (lidar) technology to record millions of points per second, measuring and mapping the precise shape and location of a structure at a high resolution. Leica Geosystems and Kuker Ranken generously provided equipment and software to support this project.
Researchers set up laser scanners (Leica BLK360 and Leica RTC360) on tripods at several sites around and inside each building, capturing three-dimensional data from different angles as the scanner rotated 360 degrees. They also sent a large drone 300 feet into the sky to acquire aerial photos.
In total, 120 scans were conducted inside and outside the structures with around 1,700 photos taken.
Geomatics Ph.D. student Mohsen Arjmand
Processing the raw data of South Falls Nature Store
Geomatics Ph.D. student Bryce Berrett
Data processing
From spring 2024 to winter 2025, researchers spent hundreds of hours processing the data collected in April 2024 and stitched the scans together to build digital models. First, the data were georeferenced into Oregon Coordinate Reference System Silver Falls Zone coordinates referenced to NAD83(2011) Epoch 2010.00 by matching to the SfM photogrammetric data in Leica Cyclone software (Cyclone Core Cyclone Field 360, and Cyclone Register 360). Using Cyclone 3DR, the researchers cropped each building, removed noise such as people passing through, and created textured 3D models from point cloud and photogrammetry data. Potree was utilized to create an interactive point cloud viewer to visualize the data online. Bentley ContextCapture software was used to share the textured 3D models.
Point cloud image of the South Falls Nature Store
Point cloud aerial image of the South Falls Lodge
Point cloud image of the Stone Kitchen Shelter
Point cloud image of the Stone Kitchen Shelter
Untextured model of the Stone Kitchen Shelter
Final textured model of the Stone Kitchen Shelter
Results
Prior to the completion of this project, the primary visual records of these historic structures are found in drawings, photos, and videos. Those media provide valuable information, but they lack dimensional detail that high resolution laser scanners can capture. Now, the combined scans and photos of the three structures at Silver Falls State Park provide a complete record for the State Park Service that could be referenced in case of damage or loss to any part of the shelters. The precise digital point clouds created from the laser scanning data will be given to the Oregon Parks and Recreation Department for them to keep and use for future restoration or rebuilding, whether due to a fire or other natural disaster, or the typical wear-and-tear that historical buildings experience.
As historic records, the team’s models of the exteriors of the structures are available virtually for the public. Please explore the three models by clicking on the images below.
Directions on navigating the 3D models:
- Double click left mouse button on the part of the model to center that section on screen
- Hold the left button and drag the mouse to orbit around that location
- Zoom in/out with the mouse's scroll wheel, or hold right button and move mouse forwards/backwards
- Hold middle mouse button to pan