Interstate-70 running through Glenwood Canyon is one of the most spectacular segments of the US Interstate system. Photo credit: Vince Matthews for the CGS. Geology March 16, 2022 The Glenwood Canyon Highway This recent RMPBS/Colorado Experience video traces the history of transportation through Colorado’s spectacular Glenwood Canyon. It focuses on the complex construction process of Interstate-70 that sought to harmonize with the geology and the landscape. Initially fraught with controversy and opposition, the Glenwood Canyon Highway is one…
Check dams along drainage ditch Hazards, Water January 14, 2022 Case Study: stormwater Stormwater runoff is excess water associated with a rain or snow storm event that flows over the land surface and is measurable in a downstream river, stream, ditch, gutter, or pipe. From a regulatory perspective, stormwater is managed through some sort of engineered conveyance and is focused…
A close-up showing the scale of one of the blocks of Castle Rock Conglomerate that is already displaced Hazards July 10, 2009 Case Study: Rockfall – St. Francis of Assisi, Castle Rock The CGS studied the site of St. Francis of Assisi Church in Castle Rock extensively after a block detached from the upper cliff face in January 1981. The block presented a risk to homes at the base of the slope south of the church, and was subsequently broken up using…
Figure 3 -- This development in west Glenwood Springs constructed a rockfall impact wall above their townhomes to protect against both rockfall and mudslides (debris flows). Photo credit: Jon White for the CGS.|Figure 2 -- Several large rocks from the western wall of the Roaring Fork River in Glenwood Springs crashed into the houses below during the early morning causing significant damage Hazards July 6, 2005 Case Study: Rockfall – Glenwood Springs The town of Glenwood Springs in west-central Colorado lies at the confluence of the Roaring Fork and Colorado rivers. The town is tightly constrained by the steep river valleys so land-development pressure is causing residential growth to push into rockfall hazard areas. In West Glenwood, on the west side…
Retaining wall settlement at the center of the image with the sorority houses in the background and the IM field in the foreground. Photo credit: T. C. Wait for the CGS.|The Rockwell clay mine area immediately south of the CSM campus along US 6 in 1977 before more recent reclamation as a golf course. The green area to the top left is part of the IM field where the subsidence occurred. Photo credit: Colorado Geological Survey.|DC resistivity survey crew from the engineering firm Zapata/Blackhawk laying out the multicore switch cables across the IM field area in 2008. Photo credit: T. C. Wait for the CGS.|Subsidence road damage near one of the sorority houses at CSM in August 2005. Photo credit: T. C. Wait for the CGS.|A drill-rig preparing boreholes for subsurface grouting under the IM field in August 2005. Photo credit: T. C. Wait for the CGS.|One of the several subsidence features in the IM field at the Colorado School of Mines in 2005. Photo credit: T. C. Wait for the CGS.|Figure from DC resistivity report from 2009 detailing some of the infrastructure Geology, Hazards April 26, 2005 Case Study: mine subsidence, CSM For decades, the west side of the Colorado School of Mines (CSM) main campus had subsidence issues related to historical mining activities. At one point, in the 1990s, one of the married student housing units in that area was so badly damaged that it was condemned. In the early…
A large sinkhole opened in January 2005 at the Ironbridge Development and Golf Course Hazards January 17, 2005 Case Study: Roaring Fork sinkhole [ED: This report from January 17, 2005 was written by Jon White, (Senior Engineering Geologist, Emeritus). Lightly edited for dated references it highlights a hazardous geological regime in the central Colorado Rockies around the Roaring Fork River Corridor.] Last week, while on the Western Slope, I was informed by…