Twyla Capurro, Employee at Engineering and Design Firm, Died in Tunnel Collapse Accident at Canton Tunnel Project in Calaveras County
CALAVERAS COUNTY, CALIFORNIA (April 15, 2026) – A 35-year-old woman from Coulterville identified as Twyla Capurro has tragically died in a collapse at the Canyon Tunnel Project in Calaveras County.
Calaveras County officials are saying that the accident took place around 3:42 PM on Tuesday. Twyla Capurro was apparently working as a tunnel geologist for an engineering firm when a tunnel suddenly collapsed and trapped her inside.
Firefighters and paramedics were called to the scene of the accident to help all of the victims. One person was reportedly outside of the tunnel and only sustained minor to moderate injuries after it collapsed.
Rescue workers were eventually able to extricate Twyla Capurro. Sadly, she was beyond medical aid and pronounced dead at the scene. One person who works for the construction company reportedly said that a portion of the tunnel came loose.
These types of accidents are distinguished from cave-ins. The tunnel was reportedly part of the Canyon Tunnel Project and spans over 12,000 feet.
A full investigation of the accident by Cal/OSHA remains ongoing at this time.
Liability for Calaveras County Tunnel Collapse Accidents
Employers in California must take reasonable precautions to protect their workers from foreseeable sources of harm. According to 29 U.S.C. § 654(a)(1), “each employer shall furnish to each of his employees employment and a place of employment which are free from recognized hazards that are causing or are likely to cause death or serious physical harm to his employees.” Multiple actions should be taken to prevent tunnel collapse accidents.
- The construction company responsible for the project should conduct a geotechnical investigation of the soil and groundwater conditions.
- Construction workers should install support structures as excavation of the tunnel progresses.
- Construction companies should work to stabilize weak zones with grouting.
- Construction companies should ensure qualified engineers and supervisors are constantly assessing work as it progresses.
When a worker is injured or killed in California, they or their surviving family members will typically have recourse through the worker’s compensation system. This is a no-fault insurance plan designed to help workers, regardless of how a workplace accident happened. Depending on how an accident took place, there could also be several sources of third-party liability for a workplace accident. A third-party liability claim may be possible if an entity separate from a worker’s employer contributed to an accident.
Third-Party Liability for Tunnel Collapse Accidents
The construction industry continues to have one of the highest fatal incident rates across all job fields. According to the Bureau of Labor Statistics, “In 2023, about 1 in 5 (20.8 percent) workplace deaths occurred in the construction industry and 38.5 percent of these deaths were due to falls, slips, and trips. The construction industry accounted for 47.8 percent of all fatal falls, slips, and trips in 2023.” There could be several sources of third-party liability for any tunnel collapse accident.
- General Contractors: A general contractor could be liable for an accident if they failed to install support structures on the sides of a tunnel as it was being excavated.
- Soil Classification Company: A company responsible for classifying soil at a construction site could also be liable for an accident. This classification of soil could lead to critical errors that make a collapse more likely.
- Construction Safety Consultants: The company responsible for overseeing safety at the worksite could face liability for a tunnel collapse if they failed to identify collapse risks during inspections.
- Utility Company: A utility company could face liability for a tunnel collapse if they undermined the tunnel by allowing underground water intrusion that weakened key structures.
Tunnel collapses are often highly complex events. The factors that contribute to any collapse could take place hours, days, or even months beforehand. These types of accidents are nearly always preventable and involve major safety lapses. It is vital that these accidents are properly investigated by a team experienced in engineering and OSHA regulations. The family of any person who died in a tunnel collapse may be able to pursue some measure of accountability and transparency through a wrongful death claim.
Investigating California Tunnel Collapse Accidents
We at Carrazco Law extend our deepest condolences to the family of Twyla Capurro. It is our sincere hope that the other victims will be able to make a full recovery. Any person who may have more information about what happened should reach out to OSHA. Many questions remain unanswered at this time. Were the walls of the tunnel properly shored and braced? When was the last safety inspection for the tunnel?
Do you need more information about a California tunnel collapse? Our team of workplace safety advocates is here for you. We care deeply that accident victims are aware of their rights and that those rights are protected through skilled advocacy. We are familiar with all of the OSHA regulations and safety guidelines related to major construction projects. Whether you just have legal questions or need a free, independent investigation into any accident, we are here to serve your needs. You can reach out to us anytime at (800) 541-3244.
