A trench drain is a long, low sloped drain much like a narrow trough submerged into the floor. Instead of having to drain liquids from just one round drain in an area of the floor, a trench drain allows for continuous drainage along a straight line.
While not required for breweries and a little more expensive than traditional floor drains, trench drains make cleaning up spills and sanitizing the brewery floor much easier. Since most brewery build-outs end up requiring the floor be opened up to place new drain lines, more breweries opt for trench drains to be installed as well.
In our case, we had a pre-existing concrete slab floor in the area of the future brewery that didn't have any floor drains. A mason used a big concrete sawcutter and jackhammer to remove a large section of concrete and dug a trench. You can see more from that day in this post.
The plumber began laying a network of pipes to serve as the drain lines here and throughout the rest of the space. The drain lines all get traced back to the main sewer line near the restrooms.
The trench drains themselves arrived in several three foot sections. Each section is numbered and has slightly different interior dimensions. When placed together consecutively, there is a continuous low slope running through the interior of the sections, but the exterior dimensions are all the same among the sections. This is designed so that installation is more straightforward without having to elevate each section differently within the ground.
The plumber carefully placed each drain section within the hole in the ground so that the tops were perfectly level. Then, a city inspector took a look at all the plumbing and approved the work.
After the inspection, dirt was carefully shoveled back into the holes around the drain lines. Kudos to our plumber who painstakingly picked out large rocks around the pipes that risk damaging the pipes.
The masonry team came back to pour concrete over the drain lines and around the drains themselves. The concrete around the trench drains was pitched slightly to allow for better runoff into the drains. It was a ton of work, but these guys got it done in just one day.
Here's the final product complete with rigid plastic grates that cover and protect the drains. Next step: Stonhard floor coating will be applied this month to provide a waterproof and chemical-resistant floor for our brewery and cooler.