What Grease Does. At Eye Level.
Lexington-Fayette Urban County Government needed a 25-foot inflatable sewer tunnel that closes in on visitors as they walk it, showing them firsthand what built-up waste does inside a pipe.
Most people never think about their sewer line until it backs up on them. Lexington wanted to reach residents before that day, so MVP Visuals built a pipe they could walk through, with grease lining the walls and gunk closing in toward the way out.
Project Snapshot
We built a cutaway sewer pipe the public could step inside. The 25 ft interior is printed with grease buildup, and sculpted inflatable “gunk” narrows the route from an 8 ft entry down to a 3 ft opening at the clogged end.
The brief: build a long tunnel that feels more clogged as people move through it. The route gets shorter and tighter, with gunk in the way, so visitors feel how waste changes a pipe.
The Problem Lives Underground
FOG (fats, oils, and grease) is hard to explain because most of the damage stays hidden. Someone pours grease down a drain at home. The buildup happens under the street. The first anyone sees of it is usually a crew opening a blocked line.
Flyers can warn people. PSAs can repeat the rules. Lexington wanted something harder to forget: a pipe residents could walk through.
Reference footage: grease beginning to build inside a working line. It looks slow and ordinary until it starts taking over the pipe.
The point: show residents a problem they do not usually see in the time it takes to walk 25 ft.
Designing a Pipe That Feels Clogged
Usually we’re making a custom inflatable logo, a product replica, or a custom mascot inflatable look good at scale. Lexington needed the opposite. The pipe had to look fouled enough to stop someone walking past, and print alone would have felt like wallpaper.
So we leaned on two moves. The walls carry the full-length grease texture, and near the end, 4.5 ft inflatable gunk pieces close in and shrink the opening from 8 ft down to 3 ft. Visitors have to duck through the lesson.
Final official proof, Order #11908, July 2024. Approved design: 25 ft printed length, 8 ft front opening, 3 ft clogged back opening, 4.5 ft gunk pieces, gray pipe exterior. Tap or click to enlarge.
From Concept to Buildup
Concept proof. The taper was there from the start: the back opening had to narrow so the tunnel felt like a clogged pipe.
Render round, June. Cutaway-pipe direction locked. Grease texture starts to cover the interior.
Final render, July. Full texture and dimensional gunk pieces in place.
Proof mattered here. If the texture repeated too obviously on a 25-foot curve, the whole thing would have looked fake. The render rounds gave us room to dial in the buildup pattern, the taper, and the gunk placement before anything went to production.
Full-Pressure Check
Before it shipped, we ran the tunnel up to full pressure and checked the practical things: does the shape hold, do the seams line up, does the print read right from a few feet back? A town-event piece also has to set up cleanly, stay firm outside, and pack down for the next outing.
Inflation test: gunk pieces narrowing the exit at full pressure.
Inflation test: the cutaway pipe form holding its shape.
Inflation test: the printed grease reads clean from straight on.
The Tunnel Tells the Story
Walk through it once and you understand the choice. The entry is open enough that a family can step in together. Inside, the walls get ugly. At the far end, the gunk closes in and leaves only a 3 ft opening. You feel the pipe losing room.
It’s the same inflatable know-how behind our race arches and finish-line tunnels, just aimed at a different feeling. Instead of framing a celebration, this one makes a hidden infrastructure problem physical.
The clogged end from outside. Before visitors step in, they can see the pipe has a problem.
The Result
Lexington asked for a structure that gets tighter the deeper you go. We delivered a 25-foot outreach piece the city can reuse, one that turns sewer buildup into something a resident understands in a short walk.
Public works teams keep running into the same problem: the public usually sees infrastructure only after something fails. A walk-through inflatable brings the consequence above ground. The same format can explain grease disposal, stormwater, recycling contamination, or water conservation.
Example use setting: the tunnel gives staff something concrete to point to while explaining how buildup narrows a sewer line.
