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How I almost died in a trench collapse

Updated: Mar 11

by Greg Strudwick

Murphy’s Law takes no prisoners. All it does is create widowers if you ignore it when doing utility construction. That was a lesson I learned the hard way many years ago, when I almost died in a trench collapse. In 1974, I was 23 years old and served as the foreman of a construction utility crew for a construction contractor. My crew and I installed underground utilities on many types of projects in the Dallas area. During the fall of 1974, our crew was chosen to install approximately 5,000 ft. of 15-inch clay tile sewer line. The job was in a remote area where multi-family apartments and commercial building sites were being planned. The job location was south of the proposed right-of-way for Interstate 20. The interstate right-of-way had been established and fenced east and west, using 6 ft. chain link fence. Our contract included working 7.5 ft. south of the fence that separated the DOT right-of-way from these commercial properties. I was assigned to install the 15-inch sewer pipe parallel to the fence for approximately 2,000 ft. The crew and I mobilized in a low-lying area adjacent to the fence at an existing manhole. Our first day included meeting with the DOT Inspector and officials from the City of Duncanville, Texas for a pre-construction review of the site and installation process. At that meeting, I was informed by the DOT inspector that our crew was not to touch the fence during the pipe installation process. At the time, our crew was very experienced; we thought we could maintain production without interfering with the fence. As we began to excavate the trench away from the manhole, we immediately encountered problems. Our flow line for the 15-inch pipe was approximately 11 ft. deep and the trench was very narrow. We excavated the trench to the flow line and encountered water approximately 7 ft. deep. We began to dewater with mud pumps so we could finish digging the trench to the base of the existing manhole where we had to make the tie-in. Once we reached grade, we tied into the manhole and began to lay pipe away from it. The process was difficult and required several days to complete. The inflow of water was continuous and required the use of centrifugal pumps running day and night to de-water the trench. To make matters worse, we had to deal with the fence and a hard layer of rock at a depth of 7 ft., which required use of jack hammers and a ladder type of trenching machine to break it up. As we slowly laid pipe to the west, we hoped conditions would improve, because we were pumping the ground water away from us. Instead, it became worse. As conditions deteriorated, the fence along the right-of-way became an impediment to safely. We couldn’t excavate and slope at a proper angle to eliminate the possible collapse of the trench wall to the right of our centerline. I became very nervous about these conditions and took steps that I thought would help to minimize the chances of a cave-in:

  1. We used the Buckeye 160 trenching machine to cut the rock at the bottom of our excavation. We then moved it away from the trench.

  2. We moved in a tracked excavator to excavate and remove the dirt, rock and debris we created using the trencher.

  3. I had the excavator operator position its bucket against the right wall of the trench to help prevent it from collapsing. With the bucket in position, the operator then shut down the machine to reduce ground vibration.

  4. A loader operator slowly approached the trench from the south side to dump the embedment gravel at the point we had excavated. Once the gravel was placed, he backed up a safe distance from the trench and shut the machine down, once again to eliminate any source of vibration.

  5. Once all machines were shut down, I asked Angel to position himself at the west end of the excavation, where he could keep an eye on the trench walls, while Mike and I quickly entered the trench, prepared the gravel and installed the 7.5 ft. joint of 15-inch diameter clay tile sewer pipe. The entire process of placing the pipe only took a few minutes, and once complete, Mike and I exited the trench as quickly as possible.

  6. The loader then placed sand over the tile pipe and backfilled the barrel of the pipe up to the bell. As the trench was backfilled, we walked the trencher back into position on the west face of the trench and our trenching process resumed again. This process was tedious, slow and dangerous, especially for Mike and I. However, we hoped that as we moved away from the existing manhole and the elevation of the pipe became shallower, conditions would improve enough for us to successfully install the pipe as we planned. Early during the second week of our installation process, we realized that this procedure wasn’t producing enough footage to meet the anticipated production levels. But we pressed ahead, following the same strategy with only marginal results. On the second Thursday of this challenging pipe installation, Mike and I were in the process of placing a joint of clay tile down on the gravel. Suddenly, we heard Angel holler, "Vamanos Rapido!"- Spanish for leave the trench, immediately! I looked up from a crouched position and saw the left side of the trench beginning to cave in  toward the right side. I immediately started in behind Mike, pushing his hips up the ramp that was our exit to the east. We were approximately 11 ft. deep and the semi-sloped trench was about 6-1/2 ft. wide. The north wall of the trench had cracked vertically from the rock ledge about a foot above our heads. As I pushed Mike up the ramp, a two-to-three foot wall of black dirt pressed me against the south wall of the trench. My arms were extended up towards Mike’s butt and the weight of the dirt wall squeezed my torso until all I could see were stars. I was being crushed by a wedge of solid material that probably weighted more than 4,000 pounds. I was nearly unconscious. Mike wheeled around, bent down, grabbed both of my hands and pulled me from the collapsing trench. The friction from the pressure of the collapsing dirt created enough pressure on my legs and lower torso that I was pulled out of my boots, socks and blue jeans. All I can recall is Mike holding me up with his arms around my chest. It felt like both of my arms had been stretched a foot longer than they were before. At 6 ft. 3 in. and 325 lbs., Mike looked like an NFL linebacker. He wasn’t just big and strong, but fast, too. At 26 years old (3 years older than me), he could outrun all of his 12 brothers. If not for his size, strength and quick thinking, I would have been a dead man. He and I both knew we were facing imminent danger each time we entered that trench, but we thought we could move fast enough to escape any cave-ins. We were only half right! Both of us were traumatized to the point that neither would allow the other to even think about challenging Mother Nature again. Still disoriented from this ordeal, I didn’t realize I was standing there in my jockey underwear until Angel told me to put my jeans back on. As I tried unsteadily to step back into my jeans, both Mike and Angel had to hold me up. I managed to make it back to my truck, where I began to get some sense of what just happened and just how lucky I was to be alive. If it hadn’t been for Angel warning us of the collapse and Mike’s quick, instinctive action, I would not be alive today. I was bruised from head to toe and it was at least a month before the soreness in my joints began to subside. To this day, over 40 years later, I can’t throw a baseball with my right arm - just a reminder that to challenge danger is the epitome of stupidity! Remember: Just because you have engaged in an unsafe activity thousands of times and nothing has happened, that doesn’t mean you’re "safe." All it takes is one incident to kill you!

Greg Strudwick is the founder and President of Greg Strudwick & Associates, a construction safety and consulting firm based in Coppell, Texas. He has been actively involved promoting safety since 1972. Currently, Greg promotes safety standards through his active membership in multiple national organizations; The National Utility Contractors Association (NUCA), the Associated General Contractors Association (AGC), and the International Association of Foundation Drillers. Looking to avoid? See: Utilities Safety Training

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