What We Pulled Out of a Trash Rack After a Flood
By Walt Kesler, Power plant maintenance manager, nuclear-qualified. Reviewed by Amanda McCallister, editor.
Cathodic Protection & Anodes | Offshore & Subsea Diving September 14, 2023. Smithland, Kentucky. The Ohio River crested at 48.2 feet at 3 a.m., and by 6 a.m. The water had dropped enough that we could get a man down to the intake structure on the east wall. I was that man. Our trash rack is a steel grid set in front of the four circulating water pumps that feed the main condensers. Each bar is 12 feet long, 1 inch thick, spaced 3 inches apart. That morning, the third bar from the left on rack No. 2 was bent in a smooth U shape, like someone had taken a bite out of it. We knew the flood was coming four days out. We walked the riverbank upstream, warned the houseboat owners we know by name, watched the marina docks pull loose. The smart folks moved their skiffs. Some didn't. We also knew we couldn't stop the river from bringing us its garbage. We just had to deal with it. The crane operator, Danny, looked at that bent bar and said, 'Well, Walt, guess we're going to earn our pay.' He wasn't wrong. Over the next nine hours we pulled out 10 things that had no business being in a power plant intake. This is that list.
The First Two: The Cloggers
The first thing we pulled was a picnic table. Aluminum frame, wooden slats, one bench still attached. It was wedged diagonally across two bars, and the force of the river had pressed it in hard enough to bend a bar slightly. That table alone cut off maybe a fifth of the flow on that side of the rack. We hooked a chain to the frame, Danny lifted, and the whole thing came up dripping river mud and leaves. It went into the dump truck without ceremony. The second was worse. A full roll of silt fence — the black fabric fence you see around construction sites — had unrolled in the water and wrapped itself around the rack like a wet blanket over a birdcage. It was probably a 100-foot roll. It had caught on the upstream face and the current was pressing it tight against the bars, sealing off the water almost completely on that side. We couldn't pull it off in one piece. We had to cut it into strips with the torch. That one took the better part of an hour.
The Ones That Could Ruin a Tuesday
Third on the list was a 5-gallon propane bottle. Grill size. It had a dented upper rim and no safety cap. We spotted it with a distinct orange reflection near the bottom of the rack. That gets your heart rate up. If the valve had snapped and the bottle had been under pressure — well, you don't take chances. We rigged a rope sling and eased it up without banging it. The valve held. It's now sitting in the yard with flagging tape on it, waiting for disposal. Fourth was a sofa. Green, floral, one arm missing. The foam was waterlogged, so it weighed as much as a small car. The frame had separated and the springs were trailing like tentacles. We spent twenty minutes just getting a hook into it. It came up in two pieces, and the smell of wet upholstery hung over the intake for a while. Fifth was the one that bent the bar. A section of dock about 10 feet by 6 feet, made of rotting 2x6s over blue plastic barrels. The river had shoved it into the rack sideways, and the leading edge had folded and caught, and the current did the rest. That bar is still on the rack, but we caged it for now. It'll be replaced during the next outage. Sixth was the actual tree. Not a limb. A trunk, maybe 18 inches at the base and 20 feet long. The bark was gone, and a piece of anchor chain was embedded in one end. It was the kind of log that would go through a trash rack if the orientation was right, and that would have been a bad day for a condenser. We got a sling around it and Danny floated it up gently — it had to be a controlled lift because it was longer than our dump truck. We ended up cutting it into two pieces with a chainsaw.
The Small and Sneaky
Seventh: a tangle of monofilament fishing line, maybe fifty feet of it, wrapped around a corroded bolt on the corner of the rack, with one rusty hook embedded in it. It's the kind of thing you miss on a routine inspection because it's thin and nearly invisible in murky water. That line can catch debris and snowball quickly. We pulled it off with a rake. Eighth: a white plastic lawn chair. One leg snapped off, but otherwise intact. It was lying flat against the rack, probably caught as the water dropped. No damage, but we had to pull it out so it didn't get driven deeper. Ninth: a rubber mud flap off a semi-truck. The brand logo was faded but recognizable, and the whole thing had wrapped itself around a temperature sensor probe that sticks into the water at the rack flange. That could have given a false reading. We cleared it off and checked the probe. Tenth: a 5-gallon bucket. Broken handle, full of river silt and a handful of old nails. It was sitting upright on the lower sill, half buried in sediment. Danny looked at it and said, 'That's someone's drywall bucket.' I didn't ask whose. We emptied it into a scrap box, and that was that.
What That List Says About Our River
Every flood delivers its own junk, but the pattern is always the same. The big items — trees, docks, sofas — are the ones you see coming and plan for. They bend bars and block flow, and they're dangerous. But the sneaky stuff — the fishing line, the mud flap, the plastic chair — is what gets into a condenser and starts plugging tubes. The local angle matters. Smithland isn't a big city. The people upstream aren't strangers. We know the houseboat owners, the dock builders, the construction crews that forget silt fence. A flood is what happens when the river gets a look at the drainage society has built. We're the last filter before those four pumps. For that one day, the trash rack was the front line of the town. We didn't need a brochure or a social media post. We just needed the crane and a couple of guys who knew how to use it. Since that flood, we've added a camera and a light on the intake, and we check it every six hours when the river is above flood stage. We also made friends with the county road crew and they give us a heads up when they see a big pile of junk coming down. That's local. That's how it works.
Frequently Asked Questions
What happens if a trash rack gets completely blocked? If it blocks, water levels rise in the intake and the pumps cavitate. The condensers lose cooling water and the plant has to reduce load or trip. That's why we're out there in the rain pulling debris. In our case we were at about 60% load while we cleaned, and we managed to keep the plant online. How long does that cleanup take? It depends on the flood. Our last one took nine hours with a four-man crew, a crane, and a dump truck. The silt fence was the worst of it. Some floods are over in a few hours; the biggest one I've worked took three days. Can you prevent flood debris from reaching the rack? You can put a floating boom upstream or a chain across the river, but on a 1,000-foot-wide river that's expensive and it doesn't stop things rolling along the bottom. We rely on good forecasts and a smart crew. You can't catch it all.